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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
____________________________________________________________________________
FORM 10-K
(Mark One)  
ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
FOR THE FISCAL YEAR ENDED
DECEMBER 31, 2023
OR
TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
Commission file number: 1-7933
___________________________________________________________________________________________
Aon plc
(Exact name of registrant as specified in its charter)
IRELAND 98-1539969
(State or other jurisdiction of(I.R.S. Employer
incorporation or organization)Identification No.)
Metropolitan Building, James Joyce Street, Dublin 1, Ireland
D01 K0Y8
(Address of principal executive offices)(Zip Code)
+353 1 266 6000
(Registrant’s Telephone Number, including area code)

Securities registered pursuant to Section 12(b) of the Act:
Title of each classTrading Symbol(s)Name of each exchange
on which registered
Class A Ordinary Shares $0.01 nominal valueAONNew York Stock Exchange
Guarantees of Aon plc’s 3.50% Senior Notes due 2024AON24New York Stock Exchange
Guarantees of Aon plc’s 3.875% Senior Notes due 2025AON25New York Stock Exchange
Guarantees of Aon plc’s 2.875% Senior Notes due 2026AON26New York Stock Exchange
Guarantees of Aon Corporation and Aon Global Holdings plc’s 2.85% Senior Notes due 2027
AON27New York Stock Exchange
Guarantees of Aon Corporation and Aon Global Holdings plc’s 2.05% Senior Notes due 2031AON31New York Stock Exchange
Guarantees of Aon Corporation and Aon Global Holdings plc’s 2.60% Senior Notes due 2031AON31ANew York Stock Exchange
Guarantees of Aon Corporation and Aon Global Holdings plc’s 5.00% Senior Notes due 2032AON32New York Stock Exchange
Guarantees of Aon Corporation and Aon Global Holdings plc’s 5.35% Senior Notes due 2033AON33New York Stock Exchange
Guarantees of Aon plc’s 4.25% Senior Notes due 2042AON42New York Stock Exchange
Guarantees of Aon plc’s 4.45% Senior Notes due 2043AON43New York Stock Exchange
Guarantees of Aon plc’s 4.60% Senior Notes due 2044AON44New York Stock Exchange
Guarantees of Aon plc’s 4.75% Senior Notes due 2045AON45New York Stock Exchange
Guarantees of Aon Corporation and Aon Global Holdings plc’s 2.90% Senior Notes due 2051AON51New York Stock Exchange
Guarantees of Aon Corporation and Aon Global Holdings plc’s 3.90% Senior Notes due 2052AON52New York Stock Exchange
Securities registered pursuant to Section 12(g) of the Act: NONE
________________________________________________________________________________________________________________________________________________________________________________
Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes  No 
Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Exchange Act. Yes  No 
Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes No 
Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes No 
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.
Large accelerated filerAccelerated filerNon-accelerated filerSmaller reporting companyEmerging growth company
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.
Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report.
If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements.
Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b).
Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes  No 
As of June 30, 2023, the aggregate market value of the registrant’s Class A Ordinary Shares held by non-affiliates of the registrant was $70,135,237,097 based on the closing sales price as reported on the New York Stock Exchange — Composite Transaction Listing.
Number of the registrant’s Class A Ordinary Shares of Aon plc, $0.01 nominal value, outstanding as of February 15, 2024: 198,297,735.
DOCUMENTS INCORPORATED BY REFERENCE
Portions of the registrant’s proxy statement for its 2024 Annual General Meeting of Shareholders are incorporated by reference in this report in response to Part III, Items 10, 11, 12, 13, and 14.

Information Concerning Forward-Looking Statements
This report contains certain statements related to future results, or states our intentions, beliefs, and expectations or predictions for the future, all of which are forward-looking statements as that term is defined in the Private Securities Litigation Reform Act of 1995, Section 27A of the Securities Act of 1933, as amended, (the “Securities Act”) and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). Forward-looking statements represent management’s expectations or forecasts of future events. These statements include statements about our plans, objectives, strategies, financial performance and outlook, trends, prospects or other future events and involve known and unknown risks that are difficult to predict. Forward-looking statements are typically identified by words such as “anticipate,” “believe,” “estimate,” “expect,” “forecast,” “project,” “intend,” “plan,” “probably,” “potential,” “looking forward,” “continue,” and other similar terms, and future or conditional tense verbs like “could,” “may,” “might,” “should,” “will,” and “would.” You can also identify forward-looking statements by the fact that they do not relate strictly to historical or current facts. For example, we may use forward-looking statements when addressing topics such as: market and industry conditions, including competitive and pricing trends; changes in our business strategies and methods of generating revenue; the development and performance of our services and products; changes in the composition or level of our revenues; our cost structure and the outcome of cost-saving or restructuring initiatives, including the impacts of the Accelerating Aon United Program; the pending acquisition of NFP; the outcome of contingencies; dividend policy; the expected impact of acquisitions, dispositions, and other significant transactions or the termination thereof; litigation and regulatory matters; pension obligations; cash flow and liquidity; expected effective tax rate; expected foreign currency translation impacts; potential changes in laws or future actions by regulators; and the impact of changes in accounting rules. These forward-looking statements are subject to certain risks and uncertainties that could cause actual results to differ materially from either historical or anticipated results depending on a variety of factors. Potential factors, which may be revised or supplemented in subsequent reports filed or furnished with the Securities and Exchange Commission, that could impact results include:
changes in the competitive environment, due to macroeconomic conditions (including impacts from instability in the banking or commercial real estate sectors) or otherwise, or damage to our reputation;
fluctuations in currency exchange, interest, or inflation rates that could impact our financial condition or results;
changes in global equity and fixed income markets that could affect the return on invested assets;
changes in the funded status of our various defined benefit pension plans and the impact of any increased pension funding resulting from those changes;
the level of our debt and the terms thereof reducing our flexibility or increasing borrowing costs;
rating agency actions that could limit our access to capital and our competitive position;
our global tax rate being subject to a variety of different factors, including the adoption and implementation in the European Union, the United States, the United Kingdom, or other countries of the Organization for Economic Co-operation and Development tax proposals or other pending proposals in those and other countries, which could create volatility in that tax rate;
changes in our accounting estimates and assumptions on our financial statements;
limits on our subsidiaries’ ability to pay dividends or otherwise make payments to their respective parent entities;
the impact of legal proceedings and other contingencies, including those arising from acquisition or disposition transactions, errors and omissions and other claims against us (including proceedings and contingencies relating to transactions for which capital was arranged by Vesttoo Ltd.);
the impact of, and potential challenges in complying with, laws and regulations of the jurisdictions in which we operate, particularly given the global nature of operations and the possibility of differing or conflicting laws and regulations, or the application or interpretation thereof, across such jurisdictions;
the impact of any regulatory investigations brought in Ireland, the United Kingdom, the United States, and other countries;
failure to protect intellectual property rights or allegations that we have infringed on the intellectual property rights of others;
general economic and political conditions in the countries in which we do business around the world;
the failure to retain, attract and develop experienced and qualified personnel, whether as a result of the pending acquisition of NFP or otherwise;
international risks associated with our global operations, including impacts from military conflicts or political instability, such as the ongoing Russian war in Ukraine and the Israel-Hamas conflict;
the effects of natural or man-made disasters, including the effects of health pandemics and the impacts of climate-related events;
any system or network disruption or breach resulting in operational interruption or improper disclosure of confidential, personal, or proprietary data, and resulting liabilities or damage to our reputation;
our ability to develop, implement, update, and enhance new technology;
the actions taken by third parties that perform aspects of our business operations and client services;
the extent to which we are exposed to certain risks, including lawsuits, related to our actions we may take in being responsible for making decisions on behalf of clients in our investment businesses or in other advisory services that we currently provide, or will provide in the future;
our ability to continue, and the costs and risks associated with growing, developing and integrating acquired business, and entering into new lines of business or products;
our ability to secure regulatory approval and complete transactions, including the pending acquisition of NFP, and the costs and risks associated with the failure to consummate proposed transactions;
changes in commercial property and casualty markets, commercial premium rates or methods of compensation;
our ability to develop and implement innovative growth strategies and initiatives intended to yield cost savings (including the Accelerating Aon United Program) and the ability to achieve such growth or cost savings;
the effects of Irish law on our operating flexibility and the enforcement of judgments against us;
adverse effects on the market price of Aon’s securities and/or operating results for any reason, including, without limitation, because of a failure to consummate the pending acquisition of NFP or the failure to realize the expected benefits of the pending acquisition of NFP (including anticipated revenue and growth synergies) in the expected timeframe, or at all;
significant transaction and integration costs or difficulties in connection with the pending acquisition of NFP or unknown or inestimable liabilities; and
potential impact of the consummation of the pending acquisition of NFP on relationships, including with suppliers, customers, employees and regulators.
Any or all of our forward-looking statements may turn out to be inaccurate, and there are no guarantees about our performance. The factors identified above are not exhaustive. Aon and its subsidiaries operate in a dynamic business environment in which new risks may emerge frequently. Accordingly, readers should not place undue reliance on forward-looking statements, which speak only as of the dates on which they are made. We are under no (and expressly disclaim any) obligation to update or alter any forward-looking statement that we may make from time to time, whether as a result of new information, future events, or otherwise. Further information about factors that could materially affect Aon, including our results of operations and financial condition, is contained in the “Risk Factors” section in Part I, Item 1A of this report.
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Table of Contents






The below definitions apply throughout this report unless the context requires otherwise:
TermDefinition
AAU Accelerating Aon United Program
ABOAccumulated Benefit Obligation
AUMAssets Under Management
BPSBasis Points
CIGCCyber Incident Governance Committee
CODMChief Operating Decision Maker
CPIConsumer Price Index
CPOChief Privacy Officer
CSOChief Security Officer
DCFDiscounted Cash Flow
DOLDepartment of Labor
E&OErrors and Omissions
EBITDAEarnings before Interest, Taxes, Depreciation, and Amortization
ERISAEmployee Retirement Income Security Act of 1974
ERMEnterprise risk management
ESGEnvironmental, Social, Corporate Governance
E.U.European Union
FCAFinancial Conduct Authority
FINRAFinancial Industry Regulatory Authority
FitchFitch, Inc.
GAAPGenerally Accepted Accounting Principles
GEOCGlobal Emergency Operations Center
GILTIGlobal Intangible Low-Tax Income
GPOGlobal Privacy Office
GSSGlobal Security Services
I&DInclusion and Diversity
LOCLetter of Credit
LPPLeadership Performance Plan
MDIMarket Derived Income
NFP
National Financial Partners
NISTNational Institute of Standards and Technology
NYSENew York Stock Exchange
OECDOrganization for Economic Co-operation and Development
PBOProjected Benefit Obligation
PCAOBPublic Company Accounting Oversight Board
PSAPerformance Share Awards
REITReal Estate Investment Trusts
ROURight-of-Use
RPGICRetirement Plan Governance and Investment Committee
RSURestricted Share Units
SOFRSecured Overnight Financing Rate
S&PStandard & Poor’s
SECSecurities and Exchange Commission
U.K.United Kingdom
U.S.United States
VIEVariable Interest Entity





PART I
Item 1.    Business
OVERVIEW
Aon plc (which may be referred to as “Aon,” the “Company,” “we,” “us,” or “our”) is a leading global professional services firm providing a broad range of risk and human capital solutions. Through our experience, global reach, and comprehensive analytics, we help clients meet rapidly changing, increasingly complex, and interconnected challenges related to risk and people. We are committed to accelerating innovation to address unmet and evolving client needs so that our clients are better informed, better advised, and able to make better decisions to protect and grow their business. Management remains focused on strengthening Aon and uniting the firm with one portfolio of capability enabled by data and analytics and one operating model to deliver additional insight, connectivity, and efficiency.
Our clients are in over 120 countries and sovereignties and include all market segments and almost every industry. This diversification of our customer base helps provide us stability in different economic scenarios that could affect specific industries, customer segments, or geographies.
We have continued to focus our portfolio on higher-margin, capital-light professional services businesses that have high recurring revenue streams and strong cash flow generation. We endeavor to make capital allocation decisions based upon return on invested capital.
On December 19, 2023, Aon entered into a definitive agreement (the “Merger Agreement”) with Randolph Acquisition Corp., a Delaware corporation and an indirect, wholly owned subsidiary of Aon (the “Acquirer”), Randolph Merger Sub LLC, a Delaware limited liability company and a direct, wholly owned subsidiary of the Acquirer, NFP Intermediate Holdings A Corp., a Delaware corporation (“NFP”), and NFP Parent Co, LLC, a Delaware limited liability company (the “NFP Seller”), pursuant to which the Acquirer will acquire NFP for an aggregate purchase price of approximately $7 billion in cash and approximately 20,000,000 class A ordinary shares, nominal value of $0.01, in capital of Aon, in each case, subject to certain adjustments as set forth in the Merger Agreement (the “Transaction”). The Company expects to fund the cash portion of the consideration with approximately $7 billion of new debt, with $5 billion raised in advance of the closing date and $2 billion raised at close of the acquisition. The acquisition is expected to be completed by mid-2024, subject to satisfaction or waiver of the closing conditions set forth in the Merger Agreement, including applicable regulatory approval.
BUSINESS SEGMENT
We operate as one segment that includes all of our continuing operations, which, as a global professional services firm, provides a broad range of risk and human capital solutions through four solution lines — Commercial risk, Reinsurance, Health, and Wealth, which make up our principal products and services. The CODM assesses the performance of the Company and allocates resources based on one segment: Aon United.
In 2023, our consolidated total revenue was $13,376 million. This includes $7,043 million in Commercial Risk Solutions, $2,481 million in Reinsurance Solutions, $2,433 million in Health Solutions, and $1,431 million in Wealth Solutions, before certain intercompany eliminations.
Principal Products and Services
Commercial Risk Solutions includes retail brokerage, specialty solutions, global risk consulting and captives management, and Affinity programs. In retail brokerage, our dedicated teams of risk professionals utilize comprehensive analytics capabilities and insights providing clients with risk advice for their organizations. We utilize Aon’s differentiated capabilities in industry sector- and segment-specific approaches, like Digital Client Solutions, to risk transfer options and deliver them through a variety of channels including bespoke solutions for complex needs, structured solutions for mid-market and small and medium-sized enterprises, and digital distribution including CoverWallet. Our specialty-focused organizational structure includes financial and professional lines, cyber, surety and trade credit, crisis management, transaction liability, climate, and intellectual property. We develop market leading insights on the most efficient risk transfer vehicles for clients in today’s complex and integrated risk environment to enable clients to make better decisions. Global risk consulting and captive management is a global leader in supporting better management of companies’ risk profiles by identifying and quantifying the risks they face, mapping out optimal risk mitigation, retention and transfer solutions and thus enabling them to be more informed to make better decisions for their businesses. Affinity programs include development, marketing, and administration of customized and targeted insurance programs, facilities, and other structured solutions, including Aon Client Treaty. We collaborate with sponsors and other privileged distribution channels through which Aon can deliver differentiated, highly targeted, and highly valuable solutions for unique risk solutions.
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Reinsurance Solutions includes treaty reinsurance, facultative reinsurance, Strategy and Technology Group and capital markets. Treaty reinsurance addresses underwriting and capital objectives on a portfolio level, allowing our clients to more effectively manage the combination of premium growth, return on capital, and rating agency interests on an integrated basis. This includes the development of more competitive, innovative, and efficient risk transfer options. Facultative reinsurance empowers clients to better understand, manage, and transfer risk through innovative facultative solutions and provides the most efficient access to the global facultative reinsurance markets. Strategy and Technology Group combines strategic advice with data-driven consulting, analytics, and modeling tools, including Tyche, ReMetrica, and PathWise, to help clients deploy capital efficiently and effectively. We develop highly customized solutions that help clients drive growth and operational efficiency, improve balance sheet strength and resiliency, and comply with regulatory and operational requirements, including through the execution of reinsurance transactions. Capital markets is a global investment bank with expertise in insurance-linked securities, capital raising, strategic advice, restructuring, and mergers and acquisitions. We partner with insurers, reinsurers, investment firms, and corporations in executing innovative risk management products, capital market solutions and corporate finance advisory services.
Health Solutions includes consulting and brokerage, consumer benefits solutions, and talent. Consulting and brokerage develops and implements innovative, customized health and benefits strategies for clients of all sizes across industries and geographies to manage risk, drive engagement, and strengthen the workforce through improved health and wellbeing. We partner with insurers and other strategic partners to develop and implement new and innovative solutions and leverage world-class analytics and technology to help clients make informed decisions and manage healthcare outcomes. Consulting and brokerage also advises multinational companies on global benefits, including insurance placement across more than 120 countries and sovereignties, program design and management, financing optimization, and enhanced employee experience, as well as assists in navigating global regulatory and compliance requirements in countries in which they operate. Consumer benefits solutions designs and delivers innovative voluntary consumer benefits that improve an employer’s total rewards strategy and positively impacts their employees’ financial and overall wellbeing. We leverage our proprietary digital platform to provide efficient enrollment strategies through an effective combination of data, analytics, and tailored products. Multi-channel and targeted communications solutions increase consumer benefit knowledge and enhance engagement. Our talent team delivers data, analytics, and advice to business leaders so they can make better workforce decisions and align their business and people strategies. We support clients across the full employee lifecycle, including talent assessment and selection, compensation benchmarking, total rewards strategy optimization, workforce analytics and benchmarking, workforce resilience planning, talent integration in transaction situations, Corporate Governance, ESG consulting, and strategic employee communication.
Wealth Solutions includes retirement consulting, pension administration, and investments consulting. Retirement consulting specializes in providing clients across the globe with strategic design consulting on their retirement programs, actuarial services, and risk management, including pension de-risking, governance, integrated pension administration and legal and compliance consulting. We also help organizations manage their balance sheet volatility. Retirement consulting and pension administration leverage Aon’s pension expertise to deliver high-quality integrated retirement services. Our customized services include outsourcing, co-sourcing and in-sourcing options. Our partnership-driven model is powered by deep pension experience and enabled with smart technology. Our investments consulting team provides public and private companies and other institutions with advice on developing and maintaining investment programs across a broad range of plan types, including defined benefit plans, defined contribution plans, endowments and foundations. Our delegated investment solutions offer ongoing management of investment programs and fiduciary responsibilities either in a partial or full discretionary model for multiple asset owners. We partner with clients to deliver our scale and experience to help them effectively manage their investments, risk, and governance and potentially lower costs. We believe in the power of connecting participants to experts to make better informed and smarter decisions about their wealth.
Revenue and Compensation
Our business generates revenues primarily through commissions, compensation from insurance and reinsurance companies for services we provide to them, and fees from customers. Commissions and fees for brokerage services vary depending upon several factors, which may include the amount of premium, the type of insurance or reinsurance coverage provided, the particular services provided to a client, insurer, or reinsurer, and the capacity in which we act. Compensation from insurance and reinsurance companies includes: (1) fees for consulting and analytics services, and (2) fees and commissions for administrative and other services provided to or on behalf of insurers and reinsurers. Fees from clients for advice and consulting services are dependent on the extent and value of the services we provide. Payment terms are consistent with current industry practices.
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Funds Held on Behalf of Clients
We typically hold funds on behalf of clients, including premiums received from clients and claims due to clients that are in transit to and from insurers. Certain funds held on behalf of clients are invested in interest-bearing premium trust accounts and can fluctuate significantly depending on when we collect and remit cash. The principal is segregated and not available for general operating purposes, although we may earn interest on these accounts.
Competition
Our business operates in a highly competitive and fragmented environment. We compete with numerous other global insurance brokers and consulting companies, including, among others, Marsh & McLennan Companies, Inc., Willis Towers Watson Public Limited Company, Arthur J Gallagher & Company, Lockton Companies, Inc., as well as numerous other global, regional, and local firms in almost every area of our business. We also compete with insurance and reinsurance companies that directly market and service their insurance products without the assistance of brokers or agents. Additionally, we compete with other businesses that do not fall into the categories above, including large financial institutions and independent consulting firms and consulting organizations affiliated with accounting, information systems, technology, human resources, and financial services firms.
Seasonality
Due to buying patterns and delivery of certain products and services in the markets we serve, revenues recognized tend to be higher in the first and fourth quarters of each fiscal year.
Licensing and Regulation
Our business activities are subject to licensing requirements and extensive regulation under the laws of countries in which we operate, including U.S. federal and state laws. See the “Risk Factors” section in Part I, Item 1A of this report for information regarding how actions by regulatory authorities or changes in legislation and regulation in the jurisdictions in which we operate may have an adverse effect on our business.
Regulatory authorities in the U.S. and most other countries in which our operating subsidiaries conduct business may require individuals, entities, and related service providers to obtain a license from a government agency, including (but not limited to) licenses to operate as insurance producers, brokers, agents, consultants, reinsurance brokers, or managing general agents.
Certain jurisdictions issue licenses only to resident entities or individuals. In such jurisdictions, if the Company has no licensed subsidiary, we may maintain arrangements with residents or business entities licensed to act in such jurisdiction. Such arrangements are subject to an internal review and approval process.
Our subsidiaries must comply with laws and regulations of the jurisdictions in which they do business. These laws and regulations are enforced by the FCA in the U.K., by federal and state agencies in the U.S., and by various regulatory agencies and other supervisory authorities in other countries through the granting and revoking of licenses to do business, the licensing of agents, the monitoring of trade practices, policy form approval, limits on commission rates, and mandatory remuneration disclosure requirements.
Insurance authorities in the U.K., U.S., and certain other jurisdictions in which our subsidiaries operate have enacted laws and regulations governing the investment of funds, such as premiums and claims proceeds, held in a fiduciary capacity for others. These laws and regulations generally require the segregation of these fiduciary funds and limit the types of investments that may be made with them.
Investment, securities, and futures licensing authorities also govern certain business activities. For example, in the U.S., we use Aon Securities LLC, an indirect, wholly owned subsidiary of Aon, and a U.S.-registered broker-dealer and investment advisor, member of FINRA and Securities Investor Protection Corporation, for investment banking, capital advisory services and other broker-dealer activities. Similar operations exist in other jurisdictions outside of the U.S.
Further, pension and financial laws and regulations, including oversight and supervision by the FCA in the U.K., the SEC and the DOL in the U.S., and regulators in other countries govern certain of the retirement-related consulting services provided by Aon and its subsidiaries and affiliates. This includes Aon subsidiaries that provide investment advisory services regulated by various U.S. federal authorities including the SEC, DOL, and FINRA, as well as authorities on the state level. In addition, other services provided by Aon and its subsidiaries and affiliates, such as trustee services and retirement and employee benefit program administrative services, are subject in various jurisdictions to pension, investment, securities, and insurance laws and regulations, and supervision.
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Clientele
Our clients operate in many businesses and industries throughout the world. No one client accounted for more than 2% of our consolidated total revenues in 2023. Additionally, we place insurance with many insurance carriers, none of which individually accounted for more than 10% of the total premiums we placed on behalf of our clients in 2023.
Aon United, Our Culture, and Human Capital Strategy
Our Culture
Our culture is driven by our values – committed as one firm to our purpose, united through trust and integrity as one inclusive, diverse team, and passionate about making our colleagues and clients successful. Our colleagues are the cornerstone of our success. Collaboration and innovation drive our culture, bringing the best of Aon to clients in a holistic and seamless manner. Our Aon United strategy defines how our colleagues work together to deliver value to clients, setting a new standard for client leadership. Aon United is brought to life through our common client value creation model which scales strategies from across the firm to bring the best of Aon to clients. Each year, Aon makes significant philanthropic contributions to various organizations, supports numerous colleague volunteer opportunities, and offers paid time off to volunteer. In 2023, we announced our 3x3 Plan to go further, faster and continue evolving with our clients and build the capability to deliver the full value of our firm over the next three years.
Colleagues
As of December 31, 2023, we employed approximately 50,000 employees and conducted our operations in more than 120 countries and sovereignties. Our colleagues’ diverse talents, expertise, and insights contribute to the success of both our firm and our clients, and we seek to attract, grow, and retain the best talent in the industry. Our Inclusive People Leadership strategy is a central part of our Aon United strategy and is a key enabler to realizing our aspirations and purpose as a firm. All our colleagues are called upon to be leaders in embracing and modeling our Aon United values and behaviors. Inclusive People Leadership at Aon is designed to ensure that all colleagues – at every stage of their career journey – are equipped and motivated to deliver on our purpose and able to achieve their full potential. Colleagues benefit from our Smart Working approach, which aims to create a healthy, productive, inclusive, and sustainable way of working, enabling colleagues to deliver their best work for clients from wherever they are best placed to do so. This strategy, which supports in person, hybrid, and virtual working, continues to be a source of positive feedback and strong engagement based on colleague surveys.
Training and Development
We invest significant resources to develop the talent needed to remain at the forefront of innovation and remain an attractive employer. Colleagues are invited to complete a broad spectrum of curricula to meet their career stage goals and developmental needs. We provide our colleagues what they need to learn, grow, and become the leaders our clients seek. From self-guided learning courses to advanced leadership programs, the curriculum is aligned to the Aon United strategy and Inclusive People Leader strategy. Our investment in technology and use of virtual and in-person based learning and development programs allows us to deliver targeted offerings designed to advance all colleagues’ development.
Colleague Engagement and Retention
Providing an engaging and rewarding colleague experience is a top priority for us and understanding colleagues’ feedback helps us to reach that goal. We use a variety of channels to facilitate open, on-going, and direct communication with colleagues. These channels include open forums and town halls with executives, colleague surveys, and engagement through our Business Resource Groups. Business Resource Groups are our independent, voluntary, non-profit associations that provide input, take action, and help identify opportunities for our firm to further commitments to Inclusion and Diversity (I&D) and belonging.
Our engagement survey process consists of frequent pulse surveys, as well as our annual all colleague support survey which enables us to understand how colleagues are engaging with their teams, the firm, and clients. This outreach effort allows us to gather insights more rapidly, take timely action to address feedback, and deliver on the needs of colleagues in real time – ensuring colleagues feel more connected, more valued and more relevant. The pulse surveys for 2023 were focused on topics such as manager and leadership support, delivering on our Aon Story, colleague wellbeing, I&D, talent acquisition and performance and rewards. Feedback from our workforce provides management with a better understanding of evolving colleague viewpoints, and ensures we are taking appropriate steps to drive colleague engagement and retention. For discussion of the risks related to the attraction and retention of senior management and other professional personnel, see the “Risk Factors” section in Part I, Item 1A of this report.
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Rewards
In addition to an inspired purpose and culture, we are proud to offer our colleagues a total rewards program that combines competitive pay, incentive opportunities, and benefits. Our compensation programs - including salary, recognition, cash, and equity incentives - are connected to our formal performance management, and career development approach. These programs serve to reward colleagues for their Aon United impact both in what they accomplish for clients, colleagues, and shareholders, how they achieve those results and how they deliver on our values. We maintain a global commitment to colleague wellbeing and play a key role in supporting colleagues across the physical, emotional, financial, and social spectrum. Our comprehensive benefit programs are competitive for the markets in which we operate and aligned with our values and culture.
Our compensation philosophy aligns with our Aon United strategy and delivering long-term shareholder value creation. Our executive incentives are based on driving results, delivery of strategic initiatives, and leadership. Beginning in 2021, 20% of the short-term incentives for senior executives are based on quantifiable performance against firm-wide inclusion initiatives.
Inclusion
We believe that inclusive and diverse teams produce better insight, better solutions and, ultimately, the best outcomes for clients and our long-term success.
We are focused on being a firm that is representative of the communities in which we operate. We achieve this by aligning inclusion actions to the following pillars: Recruitment, Education, Promotion, and Representation. We strongly believe that only when colleagues can be their authentic selves will they reach their full potential.
Our commitment to inclusion starts from the top with our Board of Directors, including its Inclusion & Wellbeing Sub-Committee. Our Global Inclusive Leadership Council is sponsored by our Chief Executive Officer and Chief People Officer. Regional Inclusive Leadership Councils and our Executive Leadership Teams are aligned to drive actions to increase the diversity of our teams. Our colleague-led Business Resource Groups also support execution and provide additional opportunities for colleagues to enhance our inclusive environment.
As of December 31, 2023, our global workforce was 54% women and 46% men, and the Aon Executive Committee, which leads the firm was 58% women and 42% men. At the manager level, 28% of senior leaders and 43% of managers with one or more direct report were women. New colleague hires for the year were 53% women and 47% men. Our U.S. workforce was 25% racially or ethnically diverse, calculated as a percentage of colleagues that have voluntarily disclosed their race or ethnicity to Aon. At the manager level, 11% of U.S. senior leaders and 18% of U.S. managers with one or more direct report were racially or ethnically diverse. New colleague hires for the year in the U.S. were 34% racially or ethnically diverse.
Apprenticeship Program
Apprenticeship programs help build a talent pipeline of highly skilled and diverse professionals while providing apprentices with advanced education and work experience. By removing some of the traditional barriers to entry-level employment, as a firm we can contribute to local workforce development and cultivate talent while improving retention rates in these entry-level roles. As a founding member of seven apprentice networks within the U.S., we partner with companies and organizations to assist them in building their own programs through sharing best practices and learnings. Across these networks, we have 206 organizations committed as of December 31, 2023.
Our two-year Apprenticeship Program, which was implemented in the UK and U.S. in 2012 and 2017, respectively, serves as an alternate route into a permanent role that normally requires a specific degree or professional experience. We provide motivated, high-potential individuals with the required training (on the job and in the classroom), professional skills development, mentorship, and experiential learning to bridge the gap. 702 Aon apprentices have been hired since the inception of the program across the U.S. and U.K. Both programs are certified apprenticeship programs, by the Department of Labor in the U.S. and the Department of Education in the U.K.
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Website Access to Reports and Other Information
Our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, and all amendments to those reports are made available free of charge through our website (https://www.aon.com) as soon as reasonably practicable after such material is electronically filed with or furnished to the SEC. Also posted on our website are the charters for our Audit, Organization and Compensation, Governance/Nominating, and Finance Committees, and Inclusion & Wellbeing Sub-Committees, our Governance Guidelines, and our Code of Business Conduct. Within the time period required by the SEC and the NYSE, we will post on our website any amendment to or waiver of the Code of Business Conduct applicable to any executive officer or director. In addition, we may announce material information to investors and the marketplace using our investor relations website. While not all of the information that we post to such website is of a material nature, some information could be deemed to be material. Accordingly, we encourage investors, the media, and others interested in our company to review the information that we share on our investor relations page on www.aon.com. The information provided on our website is not part of this report and is therefore not incorporated herein by reference.
Item 1A.    Risk Factors
The risk factors set forth below reflect risks associated with our existing and potential businesses and the industries in which we operate generally and contain “forward-looking statements” as discussed in the “Business” Section of Part I, Item 1 of this report. Readers should consider these risks in addition to the other information contained in this report because our business, financial condition, or results of operations could be materially adversely affected if any of these risks were to actually occur and the occurrence of such risks could cause our actual results to differ materially from those stated in or implied by the forward-looking statements in this document and elsewhere.
Risk Factors Summary
The following is a summary of the principal risks associated with our businesses and the industries in which we operate generally as described in more detail in this report. We encourage you to carefully review the full risk factors immediately following this summary as well as the other information in this report.
Risks Related to Our Business
An overall decline in economic and business activity could have a material adverse effect on the financial condition and results of operations of our business.
We face significant competitive pressures from traditional and non-traditional competitors that could affect our business.
If we are unable to effectively develop and implement innovative strategies, efficiencies and new solutions for our clients, our reputation, ability to compete effectively and financial condition may be adversely affected.
If our clients are not satisfied with our services, we may face additional cost, loss of profit opportunities, damage to our reputation, or legal liability.
Revenues from commission arrangements may fluctuate due to many factors, including cyclical or permanent changes in the insurance and reinsurance markets outside of our control.
The profitability of our operations may not meet our expectations due to unexpected costs, cost overruns, inflation, early contract terminations, unrealized assumptions used in our contract bidding process or the inability to maintain our prices.
Financial Risks
We are exposed to fluctuations in currency exchange rates that could negatively impact our financial results and cash flows. Similarly, changes in interest rates and deterioration of credit quality could reduce the value of our cash balances and investment portfolios and adversely affect our financial condition or results.
We have debt outstanding that could adversely affect our financial flexibility. In addition, a decline in the credit ratings of our senior debt and commercial paper may adversely affect our borrowing costs, access to capital, and financial flexibility.
Our tax assets and liabilities are subject to a variety of different factors, including the adoption and implementation of OECD tax proposals, which could create volatility in our global effective tax rate, expose us to greater than anticipated tax liabilities or cause us to adjust previously recognized tax assets and liabilities.
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We are a holding company and, therefore, may not be able to receive dividends or other payments in needed amounts from our subsidiaries.
Legal and Regulatory Risks
We are subject to E&O claims against us as well as other contingencies and legal proceedings, some of which, if determined unfavorably to us, could have a material adverse effect on our financial condition or results of operations.
Our businesses are subject to extensive governmental regulation, which could reduce our profitability, limit our growth, or subject us to legal and regulatory actions.
Failure to protect our intellectual property rights, or allegations that we have infringed on the intellectual property rights of others, could harm our reputation, ability to compete effectively, and financial condition.
Operational Risks
Our results of operations have been adversely affected and could be materially adversely affected in the future by the effects of natural or man-made disasters, including health pandemics or the impacts of climate change.
Our success depends on our ability to retain, attract and develop experienced and qualified personnel, including our senior management team and other professional personnel.
We may not recognize all of the expected benefits from our Accelerating Aon United program and other operation improvement initiatives.
Risks Related to Technology, Cybersecurity, and Data Protection
We rely on complex information technology systems and networks to operate our business. Any significant system or network disruption due to a breach in the security of our information technology systems could have a negative impact on our reputation, operations, sales, and operating results.
Improper disclosure of confidential, personal, or proprietary data could result in regulatory scrutiny, legal liability, or harm to our reputation.
Risks Related to the Pending Acquisition of NFP (the “Transaction”)
The Transaction is subject to customary closing conditions, including conditions related to regulatory approvals, and may not be completed on a timely basis, or at all, or may be completed on a basis that has a material impact on the value of the combined company. Failure to close the Transaction could negatively impact our share price and future business and financial results.
While the Transaction is pending, we are subject to business uncertainties related to our relationships with employees, clients and suppliers, which could adversely affect our business and operations. These uncertainties could also adversely affect the combined company following the Transaction.
Risks Related to Being an Irish-incorporated Company
We are incorporated in Ireland, and Irish law differs from the laws in effect in the U.S. and may afford less protection to holders of our securities.
As an Irish public limited company, certain capital structure decisions regarding the Company will require the approval of shareholders, which may limit the Company’s flexibility to manage its capital structure.
The implementation of the OECD global minimum tax regime in Ireland could have a material adverse effect on our global effective tax rate, results of operations, cash flows and financial condition.
Risks Related to Our Business
An overall decline in economic and business activity could have a material adverse effect on the financial condition and results of operations of our business.
The results of our operations are generally affected by the level of business activity of our clients, which in turn is affected by the economy of the industries and markets these clients serve. Economic downturns, volatility, or uncertainty in the broader economy or in specific markets (including as a result of endemics or pandemics, climate change, political unrest, actions by central banks, or otherwise) may cause reductions in technology and discretionary spending by our clients, which may result in
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reductions in the growth of new business or reductions in existing business. If our clients become financially less stable, enter bankruptcy, liquidate their operations or consolidate, our revenues and collectability of receivables could be adversely affected.
The demand for property and casualty insurance generally rises as the overall level of economic activity increases and generally falls as such activity decreases, affecting both the commissions and fees generated by our Commercial Risk Solutions and Reinsurance Solutions lines. The economic activity that impacts property and casualty insurance is most closely correlated with employment levels, corporate revenues, and asset values. Downward fluctuations in the year-over-year insurance premiums charged by insurers to protect against the same risk, referred to in the industry as softening of the insurance market, could adversely affect these businesses as a significant portion of the revenue is determined as a percentage of premiums charged to our clients. In addition, certain discretionary services within our business, such as Human Capital, project-related work within Commercial Risk Solutions and Health Solutions, and transaction services, may see a decrease in activity if the overall level of economic activity results in a reduction to our clients’ discretionary spending. Insolvencies and consolidations associated with an economic downturn, especially insolvencies in the insurance industry, could adversely affect our brokerage business through the loss of clients by hampering our ability to place insurance and reinsurance business. Also, error and omission claims against us, which we refer to as E&O claims, may increase in economic downturns, also adversely affecting our business. In addition, decreased underwriting capacity for insurance and reinsurance may create difficulty for our professionals to place business, which may adversely impact our ability to earn revenue.
We face significant competitive pressures from traditional and non-traditional competitors that could affect our business.
As a global professional services firm, we compete with a broad variety of firms, including global, national, regional, and local insurance companies that market and service their own products, other financial services providers, brokers, and investment managers, independent firms, and consulting organizations affiliated with accounting, information systems, technology, human resources consulting, and financial services firms. We compete with respect to service, delivery of insights, product features, price, commission structure, technology, financial strength, ability to access certain insurance markets, and name recognition. Our competitors may have better financial, technical and marketing resources, broader customer bases, greater name recognition, more comprehensive products, stronger presence in certain geographies, or more established relationships with their customers and suppliers than we have.
Alliances or mergers among competitors could affect our business. Further, we compete on pricing and the innovation and quality of our service offerings, which could be affected by competitors’ lower cost structures, product development activities, and pricing policies, any or all of which could result in better market acceptance of our competitors’ offerings than those that we offer or develop.
This competition is further intensified by an industry trend where clients elect to engage multiple brokers to service different portions of their accounts. If we fail to respond successfully to the evolving competition we face, our financial condition or results of operations might be adversely affected.
If we are unable to effectively develop and implement innovative strategies, efficiencies and new solutions for our clients, our reputation, ability to compete effectively and financial condition may be adversely affected.
Developing and implementing innovative strategies, efficient business practices, and new solutions to current and emerging client needs is important to our business. We may be unsuccessful in developing innovative strategies, or our competitors may be more successful in innovating and delivering services to meet new and existing client needs. Competitors may be able to innovate faster and respond better to evolving client demand and industry conditions, or may price their products in a manner that clients find more attractive than Aon. Further, new and non- traditional competitors, our clients’ increasing ability and determination to self-insure, and capital market alternatives to traditional insurance and reinsurance markets cause additional forms of competition and innovation that could affect our business. If we are unsuccessful in innovating, if we cannot innovate as quickly as our competitors, if we are not able to make sufficient investment in innovation, if our competitors develop more cost-effective technologies (including through the use of artificial intelligence or other emerging technologies), or if our ideas are not accepted in the marketplace, it could have a material adverse effect on our ability to obtain and complete client engagements.
For example, we have invested significantly in Aon Business Services and the development of proprietary data and analytics tools including repositories of global insurance and reinsurance placement information, which we use to help drive results for our clients in the insurance and reinsurance placement process. Our competitors have or are developing competing data and analytics tools, and their success in this space may impact our ability to differentiate our own data and analytics tools. Innovations in software, cloud computing, data and analytics, generative artificial intelligence, or other technologies that alter how our services are delivered could significantly undermine our investment in the business if we are slow to innovate or unable to take advantage of these developments.
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In addition, innovation in technology, capabilities, sources of capital for our clients’ insurance and reinsurance needs, and the entry into new lines of business, services, or products require significant investment and present additional risks to the Company, particularly in instances where the markets are new or not fully developed or where participants in such markets are new entrants. Such risks include the investment of significant time and resources; the possibility that these efforts will not be successful and could result in reputational damage to us; the possibility that the marketplace does not accept our products or services or that we are unable to retain clients that adopt our new products or services; and the risk of new or additional liabilities associated with these efforts, including potential E&O or other claims.
If our clients are not satisfied with our services, we may face additional cost, loss of profit opportunities, damage to our reputation, or legal liability.
We depend, to a large extent, on our relationships with our clients and our reputation for high-quality advice and solutions. If a client is not satisfied with our services, it could cause us to incur additional costs and impair profitability, or lose the client relationship altogether. Moreover, if we fail to meet our contractual, common law or fiduciary obligations, we could be subject to legal liability or loss of client relationships.
The nature of much of our work involves assumptions and estimates concerning future events, the actual outcome of which we cannot know with certainty in advance. For example, in our investment businesses, we may be measured based on our track record regarding judgments and advice on investments that are susceptible to influences unknown at the time the advice was given. In addition, we could make computational, software programming, or data entry or management errors. A client may claim it suffered losses due to reliance on our consulting advice or reporting, which poses risks of liability exposure and costs of defense and increased insurance premiums. Many of our clients are businesses that actively share information among themselves about the quality of service they receive from their vendors. Adverse statements or claims from clients (including clients in the public sector or whose activities are frequently covered by the press) may receive media attention or other publicity. Accordingly, poor service to one client may negatively impact our relationships with multiple other clients.
Damage to our reputation could have a material adverse effect on our business.
We advise our clients on and provide services related to a wide range of subjects and our ability to attract and retain clients is highly dependent upon the external perceptions of our level of service, trustworthiness, business practices, financial condition, and other subjective qualities. Negative perceptions or publicity regarding these matters or others could erode trust and confidence and damage our reputation among existing and potential clients and existing and future employees, which could make it difficult for us to attract new clients and employees and retain existing ones. Negative public opinion could also result from actual or alleged conduct by us or those currently or formerly associated with us. Damage to our reputation, including as a result of negative perceptions or publicity regarding a class of business, environmental matters, climate change, workforce make-up, pay equity, harassment, social justice, cyber security or data privacy, or our inability to meet commitments or client and stakeholder expectations with respect to such matters, could affect the confidence of our clients, rating agencies, regulators, stockholders, employees and third parties in transactions that are important to our business adversely affecting our business, financial condition, and operating results.
Revenues from commission arrangements may fluctuate due to many factors, including cyclical or permanent changes in the insurance and reinsurance markets outside of our control.
Revenues from commission arrangements have historically been affected by significant fluctuations arising from uncertainties and changes in the industries in which we operate. A significant portion of our revenue consists of commissions paid to us out of the premiums that insurers and reinsurers charge our clients for coverage. We have no control over premium rates, and our revenues and profitability are subject to change to the extent that premium rates fluctuate or trend in a particular direction. The potential for changes in premium rates is significant, due to pricing cyclicality in the commercial insurance and reinsurance markets.
In addition to movements in premium rates, our ability to generate premium-based commission revenue may be challenged by:
the growing availability of alternative methods for clients to meet their risk-protection needs, including a greater willingness on the part of corporations to “self-insure,” the use of so-called “captive” insurers, and the development of capital markets-based solutions and other alternative capital sources for traditional insurance and reinsurance needs that increase market capacity, increase competition, and put pressure on premiums;
decreases in available underwriting capacity for insurance and reinsurance;
fluctuation in the need for, or relevancy of, insurance;
the level of compensation, as a percentage of premium, that insurance carriers are willing to compensate brokers for placement activity;
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the growing desire of clients to move away from variable commission rates and instead compensate brokers based upon flat fees, which can negatively impact us as fees are not consistently indexed for inflation and may not rise as much as commission-based compensation;
competition from insurers seeking to sell their products directly to consumers, including online sales, without the involvement of an insurance broker; and
the growing number of technology-enabled competitors offering new risk-transfer solutions that eliminate the traditional broker-client relationship in both commercial insurance and reinsurance markets.
The profitability of our operations may not meet our expectations due to unexpected costs, cost overruns, inflation, early contract terminations, unrealized assumptions used in our contract bidding process or the inability to maintain our prices.
Our profitability is highly dependent upon our ability to control our costs and improve our efficiency. As we adapt to changes in our business and the market, adapt to the regulatory environment, enter into new engagements, acquire additional businesses, and take on new employees in new locations, we may not be able to manage our large, diverse and changing workforce, effectively control our costs, or improve our efficiency.
Our profit margin, and therefore our profitability, is largely a function of the revenue generated from our services and the staffing costs for our personnel and related expenses. Accordingly, if we are not able to maintain the rates we charge for our services or appropriately manage the staffing costs of our personnel and related expenses, we may not be able to sustain our profit margin and our profitability will suffer. The prices we are able to charge for our services are affected by a number of factors, including competitive factors, the extent of ongoing clients’ perception of our ability to add value through our services, and general economic conditions. If we cannot drive suitable cost efficiencies, our profit margins will suffer. Our cost efficiencies may also be impacted by factors such as our ability to transition consultants from completed projects to new assignments, our ability to secure new business, our ability to forecast demand for our services (and, consequently, appropriately manage the size and location of our workforce), our ability to develop, attract and retain suitable capabilities and talent, our ability to obtain third party services at favorable prices, our ability to manage key suppliers to maximize delivery, product and efficiency opportunities, inflation (including wage inflation) and the need to devote time and resources to training and professional and business development.
In our investment businesses, we advise or act on behalf of clients regarding their investments. The results of these investments are uncertain and subject to numerous factors, some of which are within our control and some which are not. Clients that experience losses or lower than expected investment returns may leave us for competitors and/or assert claims against us.
Our investment businesses provide advice to clients on: investment strategy, which can include advice on setting investment objectives, asset allocation, and hedging strategies; selection (or removal) of investment managers; the investment in different investment instruments and products; and the selection of other investment service providers such as custodians and transition managers. For some clients, we are responsible for making decisions on these matters and we may implement such decisions in a fiduciary or agency capacity without assuming title over the underlying funds or assets invested. Asset classes may experience poor absolute performance and third parties we recommend or select, such as investment managers, may underperform their benchmarks due to poor market performance, negligence, or other reasons, resulting in poor investment returns or losses. These losses may be attributable in whole or in part to alleged failures on our part or to events entirely outside of our control, including but not limited to uncertainty or volatility in financial markets due to economic, political, and regulatory conditions or pandemics. Plaintiffs have filed, and may continue to file, individual and class action lawsuits alleging investment consultants have charged excessive fees, given improper advice or taken investment actions due to conflicts of interest, or recommended investments that underperformed other investments available at the time. Defending against these claims can involve potentially significant costs, including legal defense costs, as well as cause substantial distraction, publicity and diversion of other resources. If any lawsuit – against the Company or any other investment consultant or asset manager – results in a large adverse verdict, the size of the verdict or resultant negative adverse publicity may prompt the filing of additional lawsuits. Furthermore, our ability to limit our potential liability is restricted in certain jurisdictions and in connection with claims involving breaches of fiduciary or agency duties or other alleged errors or omissions.
Financial Risks
We are exposed to fluctuations in currency exchange rates that could negatively impact our financial results and cash flows.
We face exposure to adverse movements in exchange rates of currencies other than our reporting currency, the U.S. dollar, as a significant portion of our business is located outside of the U.S. These exposures may change over time, and they could have a material adverse impact on our financial results and cash flows. Approximately 55% of our consolidated revenue is non-U.S., attributed on the basis of where the services are performed, and where products are sold, and the exposures created can have significant currency volatility. These currency exchange fluctuations create risk in both the translation of the financial
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results of our global subsidiaries into U.S. dollars for our consolidated financial statements, as well as in those of our operations that receive revenue and incur expenses other than in their respective local currencies, which can reduce the profitability of our operations based on the direction the respective currencies’ exchange rates move. A decrease in the value of certain currencies relative to other currencies could place us at a relative disadvantage compared to our competitors that benefit to a greater degree from a specific exchange rate move and can, as a result, deliver services at a lower cost or receive greater revenues from such a transaction. Although we use various derivative financial instruments to limit the impact of foreign exchange rate fluctuations, we cannot eliminate such risks, and, as a result, changes in exchange rates may adversely affect our results. For example, the strengthening of the value of the U.S. dollar versus other currencies might adversely affect the value of our products and services when translated to U.S. dollar, even if the value of such products and services has not changed in their original currency.
Changes in interest rates and deterioration of credit quality could reduce the value of our cash balances and investment portfolios and adversely affect our financial condition or results.
Operating funds available for corporate use were $1,147 million at December 31, 2023 and are reported in Cash and cash equivalents and Short-term investments. Of the total balance, $120 million was restricted to its use as of December 31, 2023. Funds held on behalf of clients and insurers were $6.9 billion at December 31, 2023 and are reported in Fiduciary assets. We also carry an investment portfolio of other long-term investments. As of December 31, 2023, these long-term investments had a carrying value of $45 million. Adverse changes in interest rates, performance, and counterparty credit quality, including default, could reduce the value of these funds and investments, thereby adversely affecting our financial condition or results. We may experience reduced investment earnings on our cash and short-term investments of fiduciary and operating funds if the yields on investments deemed to be low risk fall below their current levels, or if negative yields on deposits or investments are experienced, as we have experienced in Japan and certain jurisdictions in the E.U. On the other hand, higher interest rates could result in a higher discount rate used by investors to value our future cash flows thereby resulting in a lower valuation of the Company. In addition, during times of stress in the banking industry, counterparty risk can quickly escalate, potentially resulting in substantial losses for us as a result of our cash or other investments with such counterparties, as well as substantial losses for our clients and the insurance companies with which we work.
Our pension obligations and value of our pension assets could adversely affect our shareholders’ equity, net income, cash flow, and liquidity.
To the extent that the pension obligations associated with our pension plans continue to exceed the fair value of the assets supporting those obligations, our financial position and results of operations may be adversely affected. In particular, lower interest rates and investment returns could result in the present value of plan liabilities increasing at a greater rate than the value of plan assets, resulting in higher unfunded positions in our pension plans. In addition, the periodic revision of pension assumptions or variances of actual results from our assumptions can materially change the present value of expected future benefits, and therefore the funded status of the plans and resulting net periodic pension expense. As a result, we may experience future changes in the funded status of our plans that could require us to make additional cash contributions beyond those that have been estimated and which could adversely affect shareholders’ equity, net income, cash flow and liquidity.
Our worldwide pension plans are significant, and therefore our pension contributions and expense are sensitive to various market, demographic, and other factors. These factors include equity and bond market returns, fair value of pension assets, the assumed interest rates we use to discount our pension liabilities, foreign exchange rates, rates of inflation, mortality assumptions, potential regulatory and legal changes or developments, and counterparty exposure from various investments and derivative contracts, including annuities. Variations or developments in connection with any of these factors could cause significant changes to our financial position and results of operations from year to year. In addition, contributions are generally based on statutory requirements and local funding practices, which may differ from measurements under U.S. GAAP.
We have debt outstanding that could adversely affect our financial flexibility.
As of December 31, 2023, we had total consolidated debt outstanding of approximately $11.2 billion. The level of debt outstanding could adversely affect our financial flexibility by reducing our ability to use cash from operations for other purposes, including working capital, dividends to shareholders, share repurchases, acquisitions, capital expenditures and general corporate purposes. We also are subject to risks that, at the time any of our outstanding debt matures, we will not be able to retire or refinance the debt on terms that are acceptable to us, or at all.
As of December 31, 2023, we had two committed credit facilities outstanding. Each of these facilities is intended to support our commercial paper obligations and our general working capital needs. In addition, each of these facilities included customary representations, warranties, and covenants, including financial covenants that require us to maintain specified ratios of adjusted consolidated EBITDA to consolidated interest expense and consolidated debt to adjusted consolidated EBITDA, tested quarterly.
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A substantial portion of our outstanding debt, including certain intercompany debt obligations, contains financial and other covenants. The terms of these covenants may limit our ability to obtain, or increase the costs of obtaining, additional financing to fund working capital, capital expenditures, acquisitions, or general corporate requirements. This in turn may have the impact of reducing our flexibility to respond to changing business and economic conditions, thereby placing us at a relative disadvantage compared to competitors that have less indebtedness, or fewer or less onerous covenants associated with such indebtedness, and making us more vulnerable to general adverse economic and industry conditions.
If we cannot service our indebtedness, we may have to take actions such as selling assets, seeking additional equity, or reducing or delaying capital expenditures, strategic acquisitions, investments, and alliances, any of which could impede the implementation of our business strategy or prevent us from entering into transactions that would otherwise benefit our business. Additionally, we may not be able to take such actions or refinance any of our debt, if necessary, on commercially reasonable terms, or at all.
A decline in the credit ratings of our senior debt and commercial paper may adversely affect our borrowing costs, access to capital, and financial flexibility.
A downgrade in the credit ratings of our senior debt and commercial paper could increase our borrowing costs, reduce or eliminate our access to capital, reduce our financial flexibility, and limit our ability to implement our corporate strategy. Our senior debt ratings at December 31, 2023 were A- with a negative outlook (S&P), BBB+ with a negative outlook (Fitch), and Baa2 with a stable outlook (Moody’s). Our commercial paper ratings were A-2 (S&P), F-2 (Fitch) and P-2 (Moody’s).
Real or anticipated changes in our credit ratings will generally affect any trading market for, or trading value of, our securities. Such changes could result from any number of factors, including the modification by a credit rating agency of the criteria or methodology it applies to particular issuers, a change in the agency’s view of us or our industry, or as a consequence of actions we take to implement our corporate strategies. A change in our credit rating could adversely affect our access to capital and our competitive position.
Our tax assets and liabilities are subject to a variety of different factors, which could create volatility in our global effective tax rate, expose us to greater than anticipated tax liabilities or cause us to adjust previously recognized tax assets and liabilities.
We are, and anticipate we will be, subject to income taxes in Ireland, the U.K., the U.S. and many other jurisdictions. As a result, our global effective tax rate from period to period can be affected by many factors, including changes in tax legislation or regulations, the continuing development of regulations and other governmental action that affect the application of such legislation, our global mix of earnings, the use of global funding structures, the tax characteristics of our income, the effect of complying with transfer pricing requirements under laws of many different countries on our revenues and costs, the consequences of acquisitions and dispositions of businesses and business segments. In addition, we could be subject to increased taxation as a result of changes in eligibility for the benefits of current income tax treaties between and among Ireland, the U.K., the U.S and other countries, including any future amendments to the current income tax treaties between and among such countries, or any new statutory or regulatory provisions that might limit our ability to take advantage of any such treaties. Significant judgment is required in determining our worldwide provision for income taxes, and our determination of the amount of our tax liability is always subject to review by applicable tax authorities. Our actual global tax rate may vary from our expectation and that variance may be material.
The overall tax environment in the jurisdictions in which we are or may be subject to taxes is highly uncertain and increasingly complex. In the U.S., the Inflation Reduction Act introduced, among other changes, a 1% excise tax on certain stock redemptions by U.S. corporations (which the U.S. Treasury indicated may also apply to certain stock redemptions of foreign corporations deemed funded by their U.S. affiliates). The OECD, a global coalition of member countries, proposed a plan (commonly referred to as “Pillar Two”) to reform international taxation which includes the introduction of a 15% global minimum tax on book income with specified adjustments and determined on a country-by-country basis. The OECD proposed tax regime has been nominally accepted by many countries within and without the OECD, although implementation in each country remains subject to the possibility of significant variation, which could lead to a risk of multiple levels of taxation on Aon’s income. Ireland, the U.K. and many E.U. member states, among others, have enacted legislation to implement the global minimum tax that are consistent with the OECD proposed tax regime. Under Ireland’s Pillar Two tax regime, starting in 2024, Aon’s net income (under U.S. GAAP), with specified modifications and determined on country-by-country basis, will be subject to the 15% minimum tax. There remains significant uncertainty, however, as to how Ireland’s Pillar Two tax regime and the OECD’s past and potentially future Pillar Two guidance will ultimately apply to Aon. In any event, until further clarifications are provided, there is a risk that the global minimum tax regime could have a material adverse effect on our global effective tax rate, results of operations, cash flows and financial condition.
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We are, and anticipate we will be, subject to tax audits conducted by Ireland, the U.K., the U.S., and other tax authorities, and the resolution of such audits could impact our tax rate in future periods, as would any reclassification or other changes (such as those in applicable accounting rules) that increases the amounts we have provided for income taxes in our consolidated financial statements. The tax laws and regulations in Ireland, the U.K., the U.S., and the other tax jurisdictions in which we operate are inherently complex, and we will be obligated to make judgments and interpretations about the application of these laws and regulations to our operations and businesses. The interpretation and application of these laws and regulations could be challenged by the relevant governmental authorities, which could result in administrative or judicial procedures, actions or sanctions, which could be material.
There can be no assurance that we would be successful in attempting to mitigate the adverse impacts resulting from any changes in tax laws and regulations, including any changes in the interpretation of such tax authorities, or from audits and other matters. Our inability to mitigate the negative consequences of such actions could cause our global effective tax rate to increase, our use of cash to increase and our financial condition and results of operations to suffer.
Changes in our accounting estimates and assumptions could negatively affect our financial position and results of operations.
We prepare our consolidated financial statements in accordance with U.S. GAAP. These accounting principles require us to make estimates and assumptions that affect the reported amounts of assets and liabilities, and the disclosure of contingent assets and liabilities at the date of our consolidated financial statements. We are also required to make certain judgments that affect the reported amounts of revenues and expenses during each reporting period. We periodically evaluate our estimates and assumptions including, but not limited to, those relating to revenue recognition, pensions, recoverability of assets including customer receivables, valuation of goodwill and intangibles, contingencies, share-based payments, and income taxes. We base our estimates on historical experience and various assumptions that we believe to be reasonable based on specific circumstances. These assumptions and estimates involve the exercise of judgment and discretion, which may evolve over time in light of operational experience, regulatory direction, developments or changes in accounting principles or standards, and other factors. Actual results could differ from these estimates, or changes in assumptions, estimates, policies, or developments in the business may change our initial estimates, which could materially affect the Consolidated Statements of Income, Comprehensive Income, Financial Position, Shareholders’ Equity, and Cash Flows.
We may be required to record goodwill or other long-lived asset impairment charges, which could result in a significant charge to earnings.
Under U.S. GAAP, we review our long-lived assets for impairment when events or changes in circumstances indicate the carrying value may not be recoverable. Goodwill is assessed for impairment at least annually. Factors that may be considered in assessing whether goodwill or other long-lived assets may not be recoverable include a decline in our share price or market capitalization, reduced estimates of future cash flows and slower growth rates in our industry. We may experience unforeseen circumstances that adversely affect the value of our goodwill or other long- lived assets and trigger an evaluation of the recoverability of the recorded goodwill and other long-lived assets. Future goodwill or other long-lived asset impairment charges could materially impact our consolidated financial statements.
We are a holding company and, therefore, may not be able to receive dividends or other payments in needed amounts from our subsidiaries.
The Company is organized as a holding company, a legal entity separate and distinct from our operating entities. As a holding company without significant operations of its own, our principal assets are the shares of capital stock of our subsidiaries. We rely on dividends, interest, and other payments from these subsidiaries to meet our obligations for paying principal and interest on outstanding debt, paying dividends to shareholders, repurchasing ordinary shares, and corporate expenses. Certain of our subsidiaries are subject to regulatory requirements of the jurisdictions in which they operate or other restrictions that may limit the amounts that subsidiaries can pay in dividends or other payments to us. No assurance can be given that there will not be further changes in law, regulatory actions, or other circumstances that could restrict the ability of our subsidiaries to pay dividends or otherwise make payments to us. Furthermore, no assurance can be given that our subsidiaries may be able to make timely payments to us in order for us to meet our obligations.
Legal and Regulatory Risks
We are subject to E&O claims against us as well as other contingencies and legal proceedings, some of which, if determined unfavorably to us, could have a material adverse effect on our financial condition or results of operations.
We assist our clients with various matters, including advising on and placing insurance and reinsurance coverage and handling related claims, consulting on various human resources matters, and providing actuarial, investment consulting, and asset management services. E&O claims against us may allege our potential liability for damages arising from these services.
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E&O claims could include, for example, the failure of our employees or sub-agents, whether negligently or intentionally, to place coverage correctly or notify carriers of claims on behalf of clients, to provide insurance carriers with complete and accurate information relating to the risks being insured, or the failure to give error-free consulting or investment advice. It is not always possible to prevent and detect E&Os, and the precautions we take may not be effective in all cases. In addition, we are subject to other types of claims, litigation, and proceedings in the ordinary course of business, which along with E&O claims, may seek damages, including punitive damages, in amounts that could, if awarded, have a material adverse impact on the Company’s financial position, earnings, and cash flows. In addition to potential liability for monetary damages, such claims or outcomes could harm our reputation or divert management resources away from operating our business.
We have historically purchased, and intend to continue to purchase, insurance to cover E&O claims and other insurance to provide protection against certain losses that arise in such matters and other matters related to our operations. However, we may be unable to maintain, at commercially reasonable rates, our current levels of insurance coverage for E&O claims or other risks in future periods, and with respect to such periods may seek to utilize self-insurance programs such as captives, the funding of which may not adequately cover the costs of potential losses. Also, we have exhausted or materially depleted our coverage under some of the policies that protect us for certain years and, consequently, are self-insured or materially self-insured for some historical claims. Additionally, parts or all of an E&O claim could fall within insurance deductibles, self-insured retentions, or policy exclusions. Accruals for these exposures, and related insurance receivables, when applicable, have been provided to the extent that losses are deemed probable and are reasonably estimable. These accruals and receivables are adjusted from time to time as developments warrant and may also be adversely affected by disputes we may have with our insurers over coverage. Amounts related to settlement provisions are recorded in Other general expenses in the Consolidated Statements of Income. Discussion of some of these claims, lawsuits, and proceedings are contained in the Notes to Consolidated Financial Statements.
In addition, we provide a variety of guarantees and indemnifications to our customers and others. In the event of a default, our potential exposure is equal to the amount of the guarantee or indemnification.
The ultimate outcome of claims, lawsuits, proceedings, guarantees and indemnifications cannot be ascertained, and liabilities in indeterminate amounts may be imposed on us. It is possible that future results of operations or cash flows for any particular quarterly or annual period could be materially affected by an unfavorable resolution of these matters.
Our businesses are subject to extensive governmental regulation, which could reduce our profitability, limit our growth, or subject us to legal and regulatory actions.
Our businesses are subject to extensive legal and regulatory oversight throughout the world, including the Irish Companies Act, the U.S. securities laws, rules, and regulations, the rules and regulations promulgated by the FCA and a variety of other laws, rules, and regulations addressing, among other things, licensing, privacy and data protection, trade sanctions laws, restrictions and export controls, anti-money laundering, wage-and-hour standards, employment and labor relations, antitrust and competition, anti-corruption, currency, reserves, government contracting, and the amount of local investment with respect to our operations in certain countries. This legal and regulatory oversight could reduce our profitability or limit our growth by: increasing the costs of legal and regulatory compliance; limiting or restricting the products or services we sell, the markets we serve or enter, the methods by which we sell our products and services, the overall structure of our business units, the type of services and prices we can charge for our services, or the form of compensation we can accept from our clients, carriers, and third parties; or by subjecting our businesses to the possibility of legal and regulatory actions, proceedings, or fines.
The global nature of our operations increases the complexity and cost of compliance with laws and regulations adding to our cost of doing business. In addition, many of these laws and regulations may have differing or conflicting legal standards across jurisdictions, increasing the complexity and cost of compliance. In emerging markets and other jurisdictions with less developed legal systems, local laws and regulations may not be established with sufficiently clear and reliable guidance to provide us adequate assurance that we are operating our business in a compliant manner with all required licenses or that our rights are otherwise protected. In addition, certain laws and regulations, such as the Foreign Corrupt Practices Act and the Foreign Account Tax Compliance provisions of the Hiring Incentives to Restore Employment Act in the U.S., and the Bribery Act of 2010 in the U.K., impact our operations outside of the legislating country by imposing requirements for the conduct of overseas operations, and in several cases, requiring compliance by foreign subsidiaries.
In addition to the complexity of the laws and regulations themselves, the development of new laws and regulations or changes in application or interpretation of current laws and regulations or conflict between them also increases our legal and regulatory compliance complexity. Additionally, our acquisitions of new businesses and our continued operational changes and entry into new jurisdictions and development of new service offerings increases our legal and regulatory compliance complexity, as well as the type of governmental oversight to which we may be subject. Changes in laws and regulations could mandate significant and costly changes to the way we implement our services and solutions, impose additional licensure requirements or costs to our operations and services, or cause us to cease offering certain services or solutions. Furthermore, as
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we enter new jurisdictions or businesses and further develop and expand our services, including through acquisitions, we may become subject to additional types of laws and governmental oversight and supervision, such as those applicable to the financial lending or other service institutions. Regulatory developments that could result in changes that adversely affect us or cause us to change our business or operations include: additional requirements respecting data privacy, data security, and data usage in jurisdictions in which we operate that may increase our costs of compliance and potentially reduce the manner in which we can use data; changes in tax regulations in the jurisdictions in which we operate; regulatory actions or changes that require us to change our compensation model; or additional regulations promulgated by, regulatory bodies in jurisdictions in which we operate.
Governmental and public attention to climate change and environmental matters, including new or enhanced reporting, diligence or disclosure rules and regulations, could expand the nature, scope, and complexity of matters that we are required to control, assess, and report. These and other rapidly changing laws, rules and regulations, may increase the cost of our compliance and risk management and otherwise impact our business, which could have a material adverse effect on our business, results of operations, and financial condition. In addition, the shift toward a lower-carbon economy, driven by changes in laws, rules and regulations, low-carbon technology advancement, consumer sentiment, and/or liability risks, may negatively impact our business model and/or the business models of our clients. In addition, as governments, investors and other stakeholders face additional pressures to accelerate actions to address climate change and other ESG topics, governments and other stakeholders may impose new rules or expectations causing a shift in disclosure and other behaviors that may negatively impact our business.
In all jurisdictions, the applicable laws and regulations are subject to amendment or interpretation by regulatory authorities. Generally, such authorities are vested with relatively broad discretion to grant, renew, and revoke licenses and approvals and to implement regulations. Accordingly, we may have a license revoked or be unable to obtain new licenses and therefore be precluded or suspended from carrying on or developing some or all of our activities or otherwise be fined or penalized in a given jurisdiction. No assurances can be given that our business can further develop or continue to be conducted in any given jurisdiction in the future as it has been conducted in the past. Changes in the regulatory scheme, or even changes in how applicable regulations are interpreted, could have an adverse impact on our results of operations by limiting revenue streams or increasing costs of compliance.
Our business’ regulatory oversight also includes licensing of insurance brokers and agents, managing general agency or general underwriting operations, and the regulation of the handling and investment of client funds held in a fiduciary capacity. Our continuing ability to provide insurance broking in the jurisdictions in which we operate depends on our compliance with the rules and regulations promulgated by the regulatory authorities in each of these jurisdictions, and our failure to adhere to these rules and regulations can expose us to fines or other sanctions. Also, we can be affected indirectly by the governmental regulation and supervision of insurance companies. For instance, if we are providing or managing general underwriting services for an insurer, we may have to adhere to regulations affecting our insurer client.
Services provided in our Health Solutions and Wealth Solutions businesses are also the subject of ever-evolving government regulation, either because the services provided to our clients are regulated directly or because third parties upon whom we rely to provide services to clients are regulated, thereby indirectly affecting the manner in which we provide services to those clients. In particular, our health care exchange business depends upon the private sector of the U.S. insurance system and its role in financing health care delivery, and insurance carriers’ use and payment of commissions to agents, brokers, and other organizations to market and sell individual and family health insurance products and plans. Uncertainty regarding, or any changes to, state or federal law, or the interpretation of such law by applicable regulatory agencies could delay client adoption of our health care exchanges, impair our ability to retain clients who have adopted our health care exchanges, or cause insurance carriers to alter or eliminate the products and plans that they offer or attempt to move members into new products or plans for which we receive lower commissions. In addition, changes in laws, government regulations, or the way those regulations are interpreted in the jurisdictions in which we operate could affect the viability, value, use, or delivery of benefits and human resources programs, including changes in regulations relating to health and welfare plans (such as medical), defined contribution plans (such as 401(k)), or defined benefit plans (such as pension), may adversely affect the demand for, or profitability of, our services.
If we violate the laws and regulations to which we are subject, we could be subject to fines, penalties, or criminal sanctions and could be prohibited from conducting business in one or more countries. There can be no assurance that our employees, contractors, or agents will not violate these laws and regulations, causing an adverse effect on our operations and financial condition.
Heightened regulatory oversight and scrutiny may lead to additional regulatory investigations, increased government involvement, or enforcement actions, which could consume significant management time and resources and could have adverse effects on our business and operations. For instance, increased scrutiny by competition authorities may increase our costs of
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doing business or force us to change the way we conduct business or refrain from or otherwise alter the way we engage in certain activities. Additionally, we could suffer significant financial or reputational harm if we fail to properly identify and manage potential conflicts of interest, which exist or could exist any time we or any of our employees have or may have an interest in a transaction or engagement that is inconsistent with our clients’ interests. This could occur, for example, when we are providing services to multiple parties in connection with a transaction. We also may provide multiple types of services to certain clients from more than one of our solution lines, creating a greater potential for conflicts with advisory services.
Due to the broad scope of our businesses and our client base, we regularly address potential conflicts of interest, including, without limitation, situations where our services to a particular client or our own investments or other interests conflict, or are perceived to conflict, with the interests of another client. If these are not adequately identified and managed, this could then lead to failure or perceived failure to protect the client’s interests, with consequential regulatory and reputational risks, including litigation or enforcement actions that could adversely affect us and our operations. Identifying conflicts of interest may also prove particularly difficult as we continue to bring systems and information together and integrate newly acquired businesses. In addition, we may not be able to adequately address such conflicts of interest.
Insurance intermediaries have traditionally been remunerated by base commissions paid by insurance carriers in respect of insurance placements for clients, or by fees paid by clients. Intermediaries also obtain other revenue from insurance carriers. This revenue, when derived from carriers in their capacity as insurance markets (as opposed to as corporate clients of the intermediaries where they may be purchasing insurance or reinsurance or other non-market related services), is commonly known as MDI. MDI is another example of an area in which potential conflicts of interest may arise. This revenue may be subject to scrutiny by various regulators under conflict of interest, anti-trust, unfair competition, conduct and anti-bribery laws and regulations. MDI takes a variety of forms, including volume- or profit-based contingent commissions, facilities administration charges, business development agreements, and fees for providing consulting services to carriers. While accepting MDI is a lawful and acceptable business practice, we cannot predict whether our position will result in regulatory or other scrutiny and our controls may not be fully effective.
Failure to protect our intellectual property rights, or allegations that we have infringed on the intellectual property rights of others, could harm our reputation, ability to compete effectively, and financial condition.
To protect our intellectual property rights, we rely on a combination of trademark laws, copyright laws, patent laws, trade secret protection, confidentiality agreements, and other contractual arrangements with our affiliates, employees, clients, strategic partners, and others, as well as internal policies and procedures regarding our management of intellectual property. However, the protective steps that we take may be inadequate to deter misappropriation of our proprietary information. In addition, we may be unable to detect the unauthorized use of, or take appropriate steps to enforce, our intellectual property rights. Further, we operate in many jurisdictions and effective trademark, copyright, patent, and trade secret protection may not be available or adequate in every country or jurisdiction in which we offer our services or employ our colleagues. Additionally, our competitors may develop products similar to our products that do not infringe our intellectual property rights. Failure to protect our intellectual property adequately could harm our reputation and affect our ability to compete effectively.
In addition, to protect or enforce our intellectual property rights, we may initiate litigation against third parties, such as infringement suits or interference proceedings. Third parties may assert intellectual property rights claims against us, which may be costly to defend, could require the payment of damages, and could limit our ability to use or offer certain technologies, products, or other intellectual property. Any intellectual property claims, with or without merit, could be expensive, take significant time and divert management’s attention from other business concerns. Successful challenges against us could require us to modify or discontinue our use of technology or business processes where such use is found to infringe or violate the rights of others, or require us to purchase licenses from third parties, any of which could adversely affect our business, financial condition, and operating results.
Operational Risks
The economic and political conditions of the countries and regions in which we operate could have an adverse impact on our business, financial condition, operating results, liquidity, and prospects for growth.
Our operations in countries undergoing political change or experiencing economic instability are subject to uncertainty and risks that could materially adversely affect our business. These risks include, particularly in emerging markets, the possibility we would be subject to undeveloped or evolving legal systems, unstable governments and economies, impacts from geopolitical conflicts, and potential governmental actions affecting the flow of goods, services, and currency.
We may not realize all of the expected benefits from our restructuring plan and other operational improvement initiatives.
In 2023, we initiated a three-year restructuring program, Accelerating Aon United Program (the “Program”). The Program is intended to streamline our technology infrastructure, optimize our leadership structure and resource alignment, and reduce
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our real estate footprint to align to our hybrid working strategy. The Program will include technology-related costs to facilitate streamlining and simplifying operations, headcount reduction costs, and costs associated with asset impairments, including real estate consolidation costs. The Program is currently expected to result in cumulative costs of approximately $1,000 million, consisting of approximately $900 million of cash charges and approximately $100 million of non-cash charges.
We estimate that our annualized savings from the Program will be approximately $350 million by the end of 2026. Actual total costs, savings and timing may vary from these estimates due to changes in the scope or assumptions underlying the Program and other operational improvement initiatives. We therefore cannot assure that we will achieve the targeted savings. Unanticipated costs or unrealized savings in connection with the Program and other operational improvement initiatives could adversely affect our consolidated financial statements.
Our success depends on our ability to retain, attract and develop experienced and qualified personnel, including our senior management team and other personnel.
We depend, in material part, upon the members of our senior management team who possess extensive knowledge and a deep understanding of our business and our strategy, as well as the colleagues who are critical to developing and retaining client relationships. The unexpected loss of services of any of these senior leaders could have a disruptive effect adversely impacting our ability to manage our business effectively and execute our business strategy. Additionally, competition for professional personnel remains intense, and we are constantly working to retain, attract and develop these professionals. If we cannot successfully do so, our business, operating results, and financial condition could be adversely affected. We may also become involved in disputes and litigation in connection with our efforts to retain and hire personnel, which can be disruptive to our business and may expose us to potential liability for monetary damages. While we have plans for key management succession and long-term compensation plans designed to retain our senior management team and critical colleagues, if our succession plans and retention programs do not operate effectively, our business could be adversely affected.
We strive to maintain an equitable work environment that unlocks the full potential of all of our personnel - this includes our commitment to inclusion, focus on colleague wellness and mental health and belonging, and building a flexible work environment that meets colleague and client needs. If we are unsuccessful in maintaining such a work environment or adapting to colleague needs or expectations, we could experience difficulty attracting and retaining personnel, which could have a negative impact on our business.
Our global operations expose us to various international risks that could adversely affect our business.
Our operations are conducted globally. Accordingly, we are subject to regulatory, legal, economic, and market risks associated with global operations and sourcing, including:
difficulties in staffing and managing our offices, and overseeing joint venture operations and compliance in disparate jurisdictions, including due to unexpected inflation (including wage inflation) or job turnover, and the increased travel, infrastructure, and legal and compliance costs and risks associated with multiple international locations;
hyperinflation in certain countries;
the impacts of geopolitical conflicts;
conflicting regulations across the countries in which we do business;
imposition of investment requirements or other restrictions by governments in certain countries;
longer payment cycles;
greater difficulties in collecting accounts receivable;
insufficient demand for our services in certain jurisdictions;
our ability to execute effective and efficient cross-border sourcing of services on behalf of our clients;
the reliance on or use of third parties to perform services on behalf of the Company;
disparate tax regimes;
restrictions on the import and export of technologies; and
trade barriers.
Our business performance and growth plans could be negatively affected if we are not able to develop, implement, update, and enhance solutions to support our business operations or if we are not able to effectively drive value for our clients.
Our success depends, in part, on our ability to enhance and implement the systems necessary to operate our businesses and to achieve intended efficiencies and improvements. We may not be successful in anticipating or responding to rapid and continuing changes in technology, data and analytics, industry standards and client preferences. The effort to gain necessary expertise and achieve internal efficiencies through technology and data and analytics requires us to incur significant expenses, and we may not be successful in identifying the optimal funding priorities. We make investments in technology and data and
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analytics to operate our businesses and achieve intended efficiencies; however, our investments and enhancements may not be sufficient to respond to needs across all of our businesses. In addition, if we are not successful in developing and maintaining expertise in process excellence, technology and data trends, our business performance may be compromised.
The occurrence of natural or man-made disasters could result in declines in business and increases in claims that could adversely affect our financial condition and results of operations.
We are exposed to various risks arising out of natural disasters, including earthquakes, hurricanes, fires, floods, tornadoes, extreme weather, or other climate events; pandemic health events (such as the COVID-19 pandemic), and man-made disasters, including acts of terrorism, civil unrest, violence, military actions, and cyber-terrorism (including, but not limited to, ransomware). The continued threat of terrorism and other events or disasters may cause significant volatility in global financial markets, and a natural or man-made disaster could trigger energy shortages, public health issues, or an economic downturn or instability in the areas directly or indirectly affected by the disaster. These consequences could, among other things, result in a decline in business and increased claims from those areas. They could also result in reduced underwriting capacity, making it more difficult for our professionals to place business. Disasters also could disrupt public and private infrastructure, including communications and financial services, which could disrupt our normal business operations and negatively impact the abilities of our counterparties to pay for our services on time or at all. If access to underwriting markets for certain lines of coverage becomes unavailable or difficult due to the impact of climate change on the claims environment, this may have a negative impact on our clients’ access to coverage, which could in turn reduce our ability to place certain lines of coverage and negatively impact our business.
A natural or man-made disaster also could disrupt the operations of our counterparties or result in increased prices for the products and services they provide to us. In addition, a disaster could adversely affect the value of the assets in our investment portfolio. Finally, a natural or man-made disaster could increase the incidence or severity of E&O claims against us. Climate change may increase the likelihood or severity of a natural or man-made disaster.
Our inability to successfully recover should we experience a disaster or other business continuity problem could cause material financial loss, loss of human capital, regulatory actions, reputational harm, or legal liability.
Our operations are dependent upon our ability to protect our personnel, offices, and technology infrastructure against damage from business continuity events that could have a significant disruptive effect on our operations. Should we experience a local or regional disaster or other business continuity problem, such as a security incident or attack, a natural disaster, climate event, terrorist attack, pandemic, power loss, telecommunications failure, or other natural or man-made disaster, our continued success will depend, in part, on the availability of our personnel and office facilities, and the proper functioning of computer systems, telecommunications, and other related systems and operations. In events like these, while our operational size, the multiple locations from which we operate, and our existing back-up systems provide us with some degree of flexibility, we still can experience near-term operational challenges in particular areas of our operations. We could potentially lose access to key executives, personnel, or client data or experience material adverse interruptions to our operations or delivery of services to our clients in a disaster recovery scenario. A disaster on a significant scale or affecting certain of our key operating areas within or across regions, or our inability to successfully recover should we experience a disaster or other business continuity problem, could materially interrupt our business operations and cause material financial loss, loss of human capital, regulatory actions, reputational harm, damaged client relationships, or legal liability.
We rely on third parties to perform key functions of our business operations enabling our provision of services to our clients. These third parties may act in ways that could harm our business.
We rely on third parties, and in some cases subcontractors, to provide services, data, and information such as technology, information security, funds transfers, data processing, support functions, and administration that are critical to the operations of our business. These third parties include correspondents, agents and other brokerage and intermediaries, insurance markets, data providers, plan trustees, payroll service providers, benefits administrators, software and system vendors, business process outsourcing providers, health plan providers, investment managers, and providers of human resources, among others. As we do not fully control the actions of these third parties, we are subject to the risk that their decisions, actions, or inactions may adversely impact us and replacing these service providers could create significant delay and expense. Our failure to manage our key suppliers and our day-to-day operations with effective controls, and/or a failure by third parties to comply with service level agreements or regulatory or legal requirements in a high quality and timely manner, particularly during periods of our peak demand for their services, could result in economic, legal, and reputational harm to us. In addition, we face risks as we transition from in-house functions to third- party support functions and providers that there may be disruptions in service or other unintended results that may adversely affect our business operations. These third parties face their own technology, operating, business, and economic risks, and any significant failures by them, including the improper use or disclosure of our confidential client, employee, or company information, could cause harm to our business and reputation. An interruption in or the cessation of service by any service provider as a result of systems failures, cybersecurity or data privacy incidents
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(including, but not limited to, ransomware), capacity constraints, financial difficulties, or for any other reason could disrupt our operations, impact our ability to offer certain products and services, and result in contractual or regulatory penalties, liability claims from clients, or employees, damage to our reputation, and harm to our business.
Our business is exposed to risks associated with the handling of client funds.
Certain of our businesses collect premiums from insureds and remit the premiums to the respective insurers. We also collect claims or refunds from insurers on behalf of insureds, which are then remitted to the insureds. Consequently, at any given time, we may be holding and managing funds of our clients. This function creates a risk of loss arising from, among other things, fraud by employees or third parties, execution of unauthorized transactions, errors relating to transaction processing, or other cybersecurity events or security breaches. We are also potentially at risk in the event the financial institution in which we hold these funds suffers any kind of insolvency or liquidity event. The occurrence of any of these types of events in connection with this function could cause us financial loss and reputational harm.
In connection with the implementation of our corporate strategies and initiatives, we face risks associated with, among others, the acquisition or disposition of businesses, the integration and development of acquired businesses, and the entry into new lines of business or products.
In pursuing our corporate strategy, we often acquire other businesses or dispose of or exit businesses we currently own and we routinely are actively engaged in the process of identifying, analyzing, and negotiating possible transactions. The success of this strategy is dependent upon our ability to identify appropriate acquisition and disposition targets, negotiate transactions on favorable terms, secure regulatory approval of transactions where required, complete transactions and, in the case of acquisitions, successfully integrate them into our existing businesses and culture. If we are unable to identify appropriate acquisition targets, or if our competitors are more successful in identifying acquisition targets at favorable valuations, we may we fail to achieve desired strategic goals, capabilities and efficiencies, and our results of operations might be adversely affected. If a proposed transaction is not consummated, the time and resources spent pursuing it could adversely impact employees, clients and shareholders and the failure to consummate a proposed transaction could result in payment of termination fees and reimbursement of expenses, reputational harm, disputes and litigation and missed opportunities to locate and acquire other businesses. If acquisitions are made, there can be no assurance that we will realize the anticipated benefits of such acquisitions, including, but not limited to, revenue growth, operational efficiencies, or expected synergies, and we could incur unexpected costs in connection with integration. If we dispose of or otherwise exit certain businesses, there can be no assurance that we will not incur certain disposition related charges, will not be subject to post-closing liabilities, obligations or restrictions, will be able to reduce overhead related to the divested assets, or will realize the intended benefits of the disposition.
We may enter new lines of business or offer new products and services within existing lines of business either through acquisitions or through initiative to generate organic revenue growth. These new lines of business, products, and services may present the Company with additional risks, particularly in instances where the markets are new or not fully developed or where participants in such markets are new entrants. Such risks include the investment of significant time and resources; the possibility that these efforts will not be successful and could result in reputational damage to us; the possibility that the marketplace does not accept our products or services or that we are unable to retain clients that adopt our new products or services; and the risk of new or additional liabilities associated with these efforts, including potential E&O or other claims. In addition, many of the businesses that we acquire and develop will likely have significantly smaller scales of operations prior to the implementation of our growth strategy. If we are not able to manage the growing complexity of these businesses, including improving, refining, or revising our systems and operational practices, and enlarging the scale and scope of the businesses, our business may be adversely affected. Other risks include developing knowledge of and experience in the new business, product or service, integrating the acquired business into our systems and culture, recruiting and retaining experienced professionals, and developing and capitalizing on new relationships with experienced market participants. External factors, such as compliance with new or revised regulations, competitive alternatives, and shifting market preferences may also impact the successful implementation of a new line of business, products, or services. Failure to manage these risks in the acquisition or development of new businesses could materially and adversely affect our business, results of operations, and financial condition.
Risks Related to Technology, Cybersecurity, and Data Protection
We rely on complex information technology systems and networks to operate our business. Any significant system or network disruption due to a breach in the security of our information technology systems could have a negative impact on our reputation, operations, sales, and operating results.
We rely on the efficient, uninterrupted, and secure operation of complex information technology systems and networks, some of which are within the Company and some of which are outsourced to third parties. All information technology systems are potentially vulnerable to damage or interruption from a variety of sources, including but not limited to cyber-attacks,
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computer viruses, security breaches, and unauthorized access or improper actions by insiders or employees. We are at risk of attack by a growing list of adversaries through new and increasingly sophisticated methods of attack, including methods that take advantage of remote work scenarios. Because the techniques used to obtain unauthorized access or sabotage systems change frequently (including as a result of the use of generative artificial intelligence, such as deepfakes), we may be unable to anticipate these techniques, implement adequate preventative measures, or detect and respond quickly enough in the event of an incident or attack. We regularly experience social engineering attempts, and increasingly sophisticated attempted attacks to our systems and networks, certain of which have been successful and have resulted in unauthorized access to our systems and data. Aon has from time to time experienced cybersecurity incidents, such as computer viruses, unauthorized parties gaining access to our information technology systems, ransomware incidents, data loss via malicious and non-malicious methods, and similar incidents, which to date have not had a material impact on our business. If we are unable to efficiently and effectively maintain and upgrade our system safeguards, we may incur unexpected costs and certain of our systems may become more vulnerable to unauthorized access. Aon has from time-to-time experienced and may experience in the future problems with the information technology systems of vendors, including breakdowns or other disruptions in communication services provided by a vendor, failure of a vendor to handle current or higher volumes, difficulties in the migration of services or data to third parties or the cloud hosted by third parties, cyber-attacks, and security breaches could adversely affect our ability to deliver products and services to customers and otherwise conduct business. Additionally, we are a global and acquisitive organization and we therefore might not adequately identify weaknesses in certain of our information systems, including those of targets we acquire, which could expose us to unexpected liabilities and fines or make our own systems more vulnerable to attack. These types of incidents affecting us, our clients, insurance carriers, vendors, or other third-parties could result in intellectual property or other confidential information being lost or stolen, including client or employee personal information or company data.
We have implemented various measures to manage our risks related to system and network security and disruptions, but a security breach or a significant or extended disruption in the functioning of our information technology systems could damage our reputation, cause us to lose clients, adversely impact our operations, sales, and operating results, and require us to incur significant expense (in connection with incident response, remediation efforts, or otherwise) and divert resources to address and remediate or otherwise resolve such issues. Additionally, in order to maintain the level of security, service, and reliability that our clients require, we may be required to make significant additional investments in our information technology system.
Improper disclosure of confidential, personal, or proprietary data could result in regulatory scrutiny, legal liability, or harm to our reputation.
One of our significant responsibilities is to maintain the security and privacy of our employees’ and clients’ confidential and proprietary information, including confidential information about our clients’ and employees’ compensation, medical information, and other personally identifiable information. We maintain policies, procedures, and technological safeguards designed to protect the security and privacy of this information. Nonetheless, we have experienced cyber incidents and cannot eliminate the risk of human error, employee or vendor malfeasance, or cyber-attacks that could result in improper access to or disclosure of confidential, personal, or proprietary information. Such access or disclosure could harm our reputation and subject us to liability under our contracts and laws and regulations that protect personal data, resulting in increased costs, fines, loss of revenue, and loss of clients. The release of confidential information as a result of a security breach could also lead to litigation or other proceedings against us by affected individuals or business partners, or by regulators, and the outcome of such proceedings, which could include penalties or fines, could have a significant negative impact on our business.
In many jurisdictions, including in the E.U. and the U.S., we are subject to laws and regulations relating to the collection, use, retention, security, and transfer of this information. These laws and regulations are frequently changing and are becoming increasingly complex and sometimes conflict among the various jurisdictions and countries in which we provide services both in terms of substance and in terms of enforceability. This makes compliance challenging and expensive. Additionally, certain jurisdictions’ regulations include notice provisions that may require us to inform affected clients or employees in the event of a breach of confidential information before we fully understand or appreciate the extent of the breach. These notice provisions present operational challenges and related risk. In particular, there have been a number of recently adopted privacy laws around the globe including in China and, Brazil, and significant privacy rulings in the E.U. relating to the “Schrems II” case, which imposed significant changes to the way companies export personal data from the E.U. We have had to implement new requirements set out in these laws within our business before the effective date, requiring significant time and resources. This new guidance issued to firms by the European Regulators has and will continue to require significant time to implement and may require significant effort to review and effect applicable changes to IT systems and transfer methods. Non-compliance with new and existing laws could result in proceedings against us by governmental entities or others and additional costs in connection therewith. We expect additional jurisdictions to continue to adopt new privacy regulations and that existing regulations may be amended as governments continue to legislate in respect of personal data. We have incurred expenses and devoted resources, and will continue to incur expenses and devote resources, to bring our practices into compliance with these regulations and future regulations. Our failure to comply with or successfully implement processes in response to changing regulatory requirements in this area could result in legal liability, result in proceedings or fines against us by governmental
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entities or others, or impair our reputation in the marketplace. Further, regulatory initiatives in the area of data protection are more frequently including provisions allowing authorities to impose substantial fines and penalties, and therefore, failure to comply could also have a significant financial impact.
Risks Related to the Pending Acquisition of NFP
The completion of the Transaction is subject to a number of conditions, and if these conditions are not satisfied or waived on a timely basis, the Transaction may not be completed.
The completion of the Transaction is subject to the satisfaction or waiver of a number of conditions as set forth in the Merger Agreement, including, among others, the expiration or termination of the applicable waiting periods under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended (the “HSR Act”), the approval of regulatory authorities in the United Kingdom and Ireland, the effectiveness of a Registration Statement and the approval for listing on NYSE of the ordinary shares of Aon to be issued in connection with the Transaction. There can be no assurance that the expiration or termination of the applicable waiting periods under the HSR Act or the other conditions to the obligations of the parties to effect the Transaction will be satisfied or waived. In particular, foreign, federal, state or local governmental or regulatory authorities and, in certain instances, private parties may seek to challenge the Transaction and/or impose conditions on Aon or NFP as a condition to completion of the Transaction under applicable antitrust or other laws. In addition, there can be no assurance that any consents, clearances or approvals necessary or advisable to be obtained in connection with the Transaction will be obtained in a timely manner or at all, or whether they will be subject to actions, conditions, limitations or restrictions that may jeopardize or delay the completion of the Transaction, materially reduce or delay the anticipated benefits of the Transaction or allow the parties to terminate the Merger Agreement. Pursuant to the terms of the Merger Agreement, Aon may be required to offer and agree to undertake certain specified behavioral remedies with regulatory authorities. If Aon is required to divest assets or businesses related to NFP, there can be no assurance that it will be able to negotiate such divestitures expeditiously or on favorable terms or that the governmental authorities will approve the terms of such divestitures. If the Transaction, or the integration of the companies’ respective businesses, is not completed within the expected time frame, such delay may materially and adversely affect the synergies and other benefits that Aon expects to achieve as a result of the Transaction and could result in additional costs or liabilities, loss of revenue and other adverse effects on Aon’s business, financial condition and results of operations.
Failure to complete the Transaction could have an adverse effect on Aon.
If the Transaction is not completed for any reason, Aon’s ongoing business may be adversely affected and, without realizing any of the potential benefits of completing the Transaction, Aon will be subject to a number of risks, including the following:
Aon will be required to pay certain costs and expenses relating to the Transaction;
if the Merger Agreement is terminated under specified circumstances or circumstances related to a failure to obtain the required antitrust clearances or other regulatory clearances provided for by the Merger Agreement, Aon may be obligated to pay to NFP a termination fee equal to $250 million;
Aon may experience negative reactions from the financial markets, including negative impacts on the market price of Aon’s securities;
the manner in which clients, vendors, business partners and other third parties perceive Aon may be negatively impacted, which in turn could affect its ability to compete for new business or to obtain renewals in the marketplace;
matters relating to the Transaction (including integration planning) may require substantial commitments of time and resources by management, which could otherwise have been devoted to other opportunities that may have been beneficial to Aon; and
Aon could be subject to litigation related to any failure to close the Transaction or related to any enforcement proceeding commenced against it to perform its obligations under the Merger Agreement.
If the Transaction does not close, these risks may materialize and may adversely affect Aon’s business, financial results and market price.
Aon and NFP are subject to various uncertainties, including contractual restrictions and requirements, while the Transaction is pending that could adversely affect their businesses, financial condition and results of operations.
During the pendency of the Transaction, it is possible that customers, suppliers, commercial partners and/or other persons with whom Aon or NFP has a business relationship may elect to delay or defer certain business decisions or decide to seek to
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terminate, change or renegotiate their relationships with Aon or NFP, as the case may be, as a result of the Transaction, which could significantly reduce the expected benefits of the Transaction and/or negatively affect Aon’s or NFP’s revenues, earnings and cash flows, NFP’s future plans and the market price of Aon ordinary shares, regardless of whether the Transaction is completed. Matters relating to the Transaction (including integration planning) will require substantial commitments of time and resources by Aon management, which would otherwise have been devoted to day-to-day operations and other opportunities that may have been beneficial to Aon. Aon will also incur significant costs related to the Transaction, some of which must be paid even if the Transaction is not completed. These costs are substantial and include financial advisory, legal and accounting costs.
Each of the risks described above may be exacerbated by delays or other adverse developments with respect to the completion of the Transaction.
Uncertainties associated with the Transaction may cause a loss of management personnel and other key employees and Aon may have difficulty attracting and motivating management personnel and other key employees.
Uncertainty about the effects of the Transaction on employees may impair the ability to attract, retain and motivate key personnel during the pendency of the Transaction and, if the Transaction is completed, for a period of time thereafter. If key employees depart because of issues related to the uncertainty and difficulty of integration or a desire not to remain with Aon following the completion of the Transaction, Aon may have to incur significant costs in identifying, hiring and retaining replacements for departing employees and may lose significant expertise and talent.
Aon may encounter difficulty or high costs associated with the arrangement of any debt financing required for the Transaction.
Aon expects to fund the cash consideration payable in the Transaction and the repayment or refinancing of NFP’s existing debt arrangements contemplated by the Merger Agreement, through debt financing. Aon’s ability to obtain debt financing, and the pricing and terms thereof, will be subject to various factors, including market conditions, operating performance and Aon’s ability to incur additional debt. The receipt of financing by Aon is not a condition to completion of the Transaction and, accordingly, Aon will be required to complete the Transaction (assuming that all of the conditions to its obligations under the Merger Agreement are satisfied) whether or not debt financing is available at all or on acceptable terms.
Aon may not be able to integrate NFP successfully or manage the combined business effectively, and many of the anticipated synergies and other benefits of the Transaction may not be realized or may not be realized within the expected time frame.
Aon and NFP entered into the Merger Agreement with the expectation that the Transaction would result in various benefits, including, among other things, operating efficiencies, synergies and cost savings. Achieving the anticipated benefits of the Transaction is subject to a number of uncertainties, including whether the businesses of Aon and NFP can be integrated in an efficient and effective manner.
It is possible that the integration process could take longer than anticipated or that the management of the combined organizations and achievement of anticipated synergies could be more difficult than expected. The integration of NFP into the Aon organization could also result in the disruption of ongoing businesses, processes, systems and business relationships or inconsistencies in standards, controls, procedures, practices, policies and compensation arrangements, any of which could adversely affect Aon’s ability to achieve the anticipated benefits of the Transaction. The integration process is subject to a number of risks and uncertainties, and no assurance can be given that the anticipated benefits of the Transaction will be realized or, if realized, the timing of their realization. Failure to achieve these anticipated benefits could adversely affect Aon’s future businesses, financial condition, results of operations and prospects.
Aon will incur significant transaction and integration-related costs in connection with the Transaction, which could adversely affect Aon’s ability to execute its integration plan and achieve the anticipated benefits of the Transaction.
Aon expects to incur a number of non-recurring costs associated with the Transaction, combining the organizations and achieving anticipated synergies. These costs will be significant and additional unanticipated costs may also be incurred in connection with the Transaction and combination of the organizations. Although Aon expects that the elimination of duplicative costs, as well as the realization of other efficiencies related to the integration of the businesses of Aon and NFP, should allow the Company to offset integration-related costs over time, this net benefit may not be achieved in the near term or at all.
The global effective tax rate that will apply to Aon subsequent to the Transaction is uncertain and may vary from expectations.
No assurances can be given as to what Aon’s global effective tax rate will be after the closing of the Transaction because of, among other things, uncertainty regarding the global mix of income following closing, uncertainty regarding the ability,
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costs and time necessary to integrate NFP’s business operations and entities, uncertainty regarding complex tax rules in NFP’s largest jurisdiction (the U.S.) and the application of those rules to Aon following closing, and uncertainty with respect to Ireland’s Pillar Two tax regime which will apply to the combined income and taxes of Aon and NFP following closing. As a result, Aon’s actual global effective tax rate may vary from expectations following the Transaction and that variance may be material.
Risks Related to Being an Irish-incorporated Company
We are incorporated in Ireland, and Irish law differs from the laws in effect in the U.S. and may afford less protection to holders of our securities.
It may not be possible to enforce court judgments obtained in the U.S. against us in Ireland, based on the civil liability provisions of the U.S. federal or state securities laws. In addition, there is some uncertainty as to whether the courts of Ireland would recognize or enforce judgments of U.S. courts obtained against us or our directors or officers based on the civil liabilities provisions of the U.S. federal or state securities laws or hear actions against us or those persons based on those laws. We have been advised that the U.S. currently does not have a treaty with Ireland providing for the reciprocal recognition and enforcement of judgments in civil and commercial matters. Therefore, a final judgment for the payment of money rendered by any U.S. federal or state court based on civil liability, whether or not based solely on U.S. federal or state securities laws, would not automatically be enforceable in Ireland.
As an Irish company, we are governed by the Irish Companies Act, which differs in some material respects from laws generally applicable to U.S. corporations and shareholders, including, among others, differences relating to interested director and officer transactions and shareholder lawsuits. Likewise, the duties of directors and officers of an Irish company generally are owed to the company only. Shareholders of Irish companies generally do not have a personal right of action against directors or officers of the company and may exercise such rights of action on behalf of the company only in limited circumstances. Accordingly, holders of our securities may have more difficulty protecting their interests than would holders of securities of a corporation incorporated in a jurisdiction of the U.S.
In addition, depending on the circumstances, the acquisition, ownership and/or disposition of our ordinary shares may subject shareholders to different or additional tax consequences under Irish law including, but not limited to, Irish stamp duty, dividend withholding tax and capital acquisitions tax.
As an Irish public limited company, certain capital structure decisions regarding the Company will require the approval of shareholders, which may limit the Company’s flexibility to manage its capital structure.
Irish law generally provides that a board of directors may allot and issue shares (or rights to subscribe for or convert into shares) if authorized to do so by a company’s constitution or by an ordinary resolution of shareholders. Such authorization may be granted in respect of up to the entirety of a company’s authorized but unissued share capital and for a maximum period of five years, at which point it must be renewed by another ordinary resolution. The Company’s constitution authorizes our directors to allot shares up to the maximum of the Company’s authorized but unissued share capital for a period of five years from March 31, 2020. This authorization will need to be renewed by ordinary resolution upon its expiration and at periodic intervals thereafter. Under Irish law, an allotment authority may be given for up to five years at each renewal, but governance considerations may result in renewals for shorter periods or in respect of less than the maximum permitted number of shares being sought or approved.
Irish law also generally provides shareholders with statutory pre-emption rights when new shares are issued for cash. However, it is possible for such statutory pre-emption rights to be dis-applied in a company’s constitution or by a special resolution of shareholders. Such dis-application of pre-emption rights may be given in respect of up to the entirety of a company’s authorized but unissued share capital and for a maximum period of five years, at which point it must be renewed by another special resolution. The Company’s constitution dis-applies statutory pre-emption rights up to the maximum of the Company’s authorized but unissued share capital for a period of five years from March 31, 2020. This dis-application will need to be renewed by special resolution upon its expiration and at periodic intervals thereafter. Under Irish law, a dis-application of statutory pre-emption rights may be given for up to five years at each renewal, but governance considerations may result in renewals for shorter periods or in respect of less than the maximum permitted number of unissued shares being sought or approved.
Irish law requires us to have available “distributable profits” to pay dividends to shareholders and generally to make share repurchases and redemptions.
Under Irish law, we may only pay dividends and, generally, make share repurchases and redemptions from distributable profits. Distributable profits may be created through the earnings of the Company or other methods (including certain intra-group reorganizations involving the capitalization of the Company’s un-distributable profits and their subsequent reduction).
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While it is our intention to maintain a sufficient level of distributable profits in order to pay dividends on our ordinary shares and make share repurchases, there is no assurance that the Company will maintain the necessary level of distributable profits to do so.
Item 1B.    Unresolved Staff Comments
None.
Item 1C.    Cybersecurity
Aon has from time-to-time experienced cybersecurity incidents. In the event of a cybersecurity incident, Aon responds in accordance with our policies, processes, applicable laws and regulations. When necessary, Aon also engages third parties, such as external cybersecurity advisors to investigate and remediate incidents. To date, the cybersecurity incidents have not had a material impact on our business strategy, results of operations, or financial condition. For additional information regarding the risks from cybersecurity threats, please see the risk factors entitled “We rely on complex information technology systems and networks to operate our business. Any significant system or network disruption due to a breach in the security of our information technology systems could have a negative impact on our reputation, operations, sales and operating results” and “Improper disclosure of confidential, personal, or proprietary data could result in regulatory scrutiny, legal liability, or harm to our reputation” in Part I, Item 1A of this report.
Aon strives to protect the personal and confidential data of our clients and our colleagues. To do so, Aon engages in a risk-based approach to adopting and implementing technical, organizational, administrative, and physical safeguards for cybersecurity. One key component to safeguard against risks facing Aon’s technology and security is Aon’s enterprise risk management (“ERM”) program. Aon’s management carries out the processes, controls, and practices of the Company’s ERM program, including the identification, assessment, prioritization, and mitigation of cybersecurity risks.
The Company’s Board of Directors (“Board”) oversees Aon’s ERM program and allocates certain oversight responsibilities to its committees and any sub-committees, as appropriate. The Board has delegated to the Audit Committee the primary responsibility for the oversight of the Company’s ERM program. The Audit Committee also has primary responsibility for the oversight of cybersecurity risk and engages in regular discussion with management regarding cybersecurity and privacy risk mitigation and incident management. Cybersecurity matters are an important focus of our Board’s oversight of risk. The Company’s management, including the Chief Security Officer (“CSO”), regularly presents to the Audit Committee of the Board regarding cybersecurity matters. In addition, members of senior management attend Board and committee meetings to address any questions or concerns raised by the Board related to risk management, including relating to cybersecurity, and any other matters.
In addition, Aon maintains a Global Security Services (“GSS”) organization, led by the CSO, with dedicated security personnel responsible for protecting Aon’s people, property and information. Aon’s CSO reports to Aon’s Chief Operating Officer and is an experienced technology and cybersecurity professional, with over 20 years’ experience in information security and technology.
The Company’s Global Emergency Operations Center (“GEOC”) serves as a single point of control, coordination, and communication for protecting Aon's people, property, and information. The GEOC is responsible for triage of all incidents pertaining to the confidentiality, integrity, and availability of customer data. The GEOC monitors threat intelligence reporting and receives alerts and reports from Aon colleagues and IT systems. In coordination with the Global Privacy Office (“GPO”) and GSS, the GEOC reports significant cybersecurity incidents to the Cyber Incident Governance Committee (“CIGC”).
The CIGC is comprised of members of management, and is responsible for reviewing significant cybersecurity incidents. The CIGC includes the CSO, the Chief Privacy Officer (“CPO”), and other representatives from the Company’s GPO and GSS, as well as leaders from the Company’s operations, risk management, law & compliance, controllership, internal audit, and communications functions. The CIGC reviews and assesses cybersecurity incidents and is responsible for coordinating the mitigation and remediation of such incidents.
The Company regularly conducts security scanning and reviews of regulatory IT controls (including Sarbanes Oxley). Additional security reviews may be triggered in connection with the assessment of new projects, business initiatives or third-party/supplier engagements. The Company’s Internal Audit function follows a risk-based approach to evaluating controls over key enterprise risks, including cybersecurity, as well as compliance with select regulations and corporate policies.
Aon has established a third-party risk governance program that creates guidelines for selecting and managing its suppliers, including assessing of their operational capabilities, adherence to the Company’s data security requirements, and technical, organizational, and physical safeguards. Contractual requirements and periodic reviews are designed to promote compliance with Aon’s security requirements. Aon’s GPO and Law & Compliance Department work with business units to incorporate appropriate controls into supplier contracts.
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The Company’s controls align to the National Institute of Standards and Technology (“NIST”) Framework. This does not imply that we meet technical specifications or requirements at all times but that the aforementioned frameworks help us identify, assess, and manage cybersecurity risks relevant to our business.
We use the aforementioned risk-based approach to cybersecurity to promote accountability for all of our functions across our businesses as well as our third parties to monitor for and prevent any adverse consequences from cybersecurity risks. These risks are continuously evolving, and our program is designed to evaluate these risks on an ongoing basis.
Item 2.    Properties
We have offices in various locations throughout the world. Substantially all of our offices are located in leased premises. We maintain our corporate headquarters at Metropolitan Building, James Joyce Street, Dublin 1, Ireland, where we occupy approximately 43,000 square feet of space under an operating lease agreement that expires in 2032. The following are additional significant leased properties, along with the occupied square footage and expiration.
Property:Occupied
Square Footage
Lease
Expiration Dates
200 E. Randolph Street, Chicago, Illinois312,0002030
165 Broadway, New York, New York217,0002028
122 Leadenhall Street, London, England178,0002034
4 Overlook Point, Lincolnshire, Illinois174,0002024
As leases expire, we do not anticipate difficulty in negotiating renewals or finding other satisfactory space if the premise becomes unavailable. We believe that the facilities we currently occupy are adequate for the purposes for which they are being used and are well maintained. In certain circumstances, we may have unused space and may seek to sublet such space to third parties, depending upon the demands for office space in the locations involved. See Note 9 “Lease Commitments” of the Notes to Consolidated Financial Statements in Part II, Item 8 of this report for information with respect to our lease commitments as of December 31, 2023.
Item 3.    Legal Proceedings
We hereby incorporate by reference Note 16 “Claims, Lawsuits, and Other Contingencies” of the Notes to Consolidated Financial Statements in Part II, Item 8 of this report.
Item 4.    Mine Safety Disclosure
Not applicable.
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Information about our Executive Officers
The executive officers of Aon, as of February 16, 2024 unless otherwise noted, their business experience during a period of the last five years or longer, and their ages and positions held are set forth below.
NameAgePosition
Eric Andersen59President. Mr. Andersen joined Aon in 1997 upon the completion of the acquisition of Minet. Mr. Andersen has served in a variety of roles during his more than 20 year career at Aon, including as Chief Executive Officer of Aon Risk Solutions Americas from 2011 to 2013, and Chief Executive Officer of Aon Benfield from September 2013 to May 2018. Mr. Andersen was appointed Co-President of the Company in May 2018 and became President in February 2020. He was named an Executive Officer in February 2017.
Gregory C. Case61
Chief Executive Officer. Mr. Case became Chief Executive Officer of Aon in April 2005. He also served as Aon’s President from April 2005 to May 2018. Prior to joining Aon, Mr. Case was a partner with McKinsey & Company, a global management consulting firm, for 17 years, most recently serving as head of the Financial Services Practice. He previously was responsible for McKinsey’s Global Insurance Practice and was a member of McKinsey’s governing Shareholders’ Committee. Prior to joining McKinsey, Mr. Case worked for the investment banking firm of Piper, Jaffray and Hopwood and the Federal Reserve Bank of Kansas City.
Christa Davies52
Chief Financial Officer. Ms. Davies became Executive Vice President - Global Finance in November 2007. In March 2008, Ms. Davies assumed the additional role of Chief Financial Officer. Prior to joining Aon, Ms. Davies served for 5 years in various capacities at Microsoft Corporation, an international software company, most recently serving as Chief Financial Officer of the Platform and Services Division. Before joining Microsoft in 2002, Ms. Davies served at ninemsn, an Australian joint venture with Microsoft.
Michael Neller45
Chief Accounting Officer and Global Controller. Mr. Neller joined Aon in August 2011 as its Vice President, Technical Accounting and Policy. From December 2011 to February 2018, Mr. Neller served as Aon’s Deputy Global Controller. In this role, he was responsible for Aon’s Latin America and North America regions, as well as global accounting policy, corporate accounting, and external reporting. Before joining Aon, Mr. Neller served from July 2009 to August 2011 as a Senior Manager of KPMG LLP, an international public accounting firm, in its Department of Professional Practice (National Office). He was named Senior Vice President and Global Controller in February 2018.
Mindy Simon47Chief Operating Officer. Ms. Simon joined Aon as Chief Operating Officer in October 2022. Prior to joining Aon, Ms. Simon served as Chief Information Officer for Conagra Brands since June 2017. Prior to her role as Chief Information Officer, Ms. Simon held a variety of roles in finance and information technology with Conagra Brands since joining the company in 2000, including serving as VP Global Business Services from January 2016 to June 2017, and VP Information Technology from 2008 to 2016.
Jillian Slyfield50
Chief Innovation Officer. Ms. Slyfield joined Aon in November 2015 as an Account Executive and later served as the Resident Sales Director for San Francisco until her appointment to Managing Director, Digital Economy Practice Leader in 2018. Ms. Slyfield was appointed Chief Innovation Officer of Aon in December 2021. Prior to joining Aon in 2015, Ms. Slyfield held client executive and commercial insurance executive positions at Marsh and Wells Fargo Insurance Services.
Lisa Stevens53
Chief People Officer and Head of Global Human Capital Solutions. Ms. Stevens joined Aon in December 2018 as Global Executive Vice President and was named as Chief People Officer in October 2019. Prior to joining Aon, Ms. Stevens held a variety of roles during her 29-year career at Wells Fargo, most recently as Executive Vice President where she led the Western Region for the Community Bank.
Andy Weitz47
Chief Marketing Officer. Mr. Weitz joined Aon in 2014 as Senior Vice President for Global Marketing and Communications. Before joining Aon, Mr. Weitz was President and CEO of the U.S. region for Hill + Knowlton Strategies, a global strategic communications consultancy. Prior to Hill + Knowlton, Mr. Weitz worked at Marsh, Inc., a global insurance brokerage, and served in various roles at Trilogy, Inc. a software company.
Darren Zeidel52
General Counsel and Company Secretary. Mr. Zeidel was named General Counsel and Company Secretary in July 2019. Prior to this Mr. Zeidel held several leadership roles with Aon, including as Deputy General Counsel immediately prior to his appointment; Global Chief Counsel - Corporate, Retirement & Investment and Health Exchanges from 2017 to 2019; and Global Chief Counsel of Aon Hewitt upon joining Aon in 2012 to 2017. Before this Mr. Zeidel worked for Honeywell, where he held business segment general counsel roles in the aerospace strategic business unit and at Honeywell UOP LLC. Mr. Zeidel began his career as an Associate in the Mergers and Acquisitions group in the New York office of Skadden, Arps, Slate, Meagher & Flom, LLP.
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PART II
Item 5.    Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities
Our class A ordinary shares, $0.01 nominal value per share, are traded on the NYSE under the trading symbol AON.
In February 2024, Aon paid a quarterly cash dividend of $0.615 per share. The declaration of future cash dividends is at the discretion of our Board of Directors and will depend upon our future earnings, liquidity, cash flows, capital allocation, financial conditions, and other factors.
On February 15, 2024, the last reported sale price of our ordinary shares as reported by the NYSE was $314.37 per share. We have approximately 392 holders of record of our class A ordinary shares as of February 16, 2024.
The following information relates to the repurchases of equity securities by Aon or any affiliated purchaser during each month within the fourth quarter of the fiscal year covered by this report:
PeriodTotal Number of Shares Purchased
Average Price Paid per Share (1)
Total Number of Shares Purchased as Part of Publicly Announced Plans or Programs (2)
Maximum Dollar Value of Shares that May Yet Be Purchased Under the Plans or Programs (1) (2)
10/1/23 – 10/31/23811,155 $320.98 811,155 $3,806,897,048 
11/1/23 – 11/30/23858,950 $327.18 858,950 $3,525,862,650 
12/1/23 – 12/31/23660,279 $315.92 660,279 $3,317,269,632 
2,330,384 $321.83 2,330,384 $3,317,269,632 
(1)Does not include commissions paid to repurchase shares.
(2)The Repurchase Program was established in April 2012 with $5.0 billion in authorized repurchases and was increased by $5.0 billion in authorized repurchases in each of November 2014, June 2017, and November 2020, and by $7.5 billion in February 2022 for a total of $27.5 billion in repurchase authorizations.
Information relating to the compensation plans under which equity securities of Aon are authorized for issuance is set forth under Part III, Item 12 “Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters” of this report and is incorporated herein by reference.
We did not make any unregistered sales of equity in 2023.
Item 6.    [Reserved]
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Item 7.    Management’s Discussion and Analysis of Financial Condition and Results of Operations
EXECUTIVE SUMMARY OF 2023 FINANCIAL RESULTS
Aon plc is a leading global professional services firm providing a broad range of risk and human capital solutions. Through our experience, global reach, and comprehensive analytics, we help clients meet rapidly changing, increasingly complex, and interconnected challenges related to risk and people. We are committed to accelerating innovation to address unmet and evolving client needs so that our clients are better informed, better advised, and able to make better decisions to protect and grow their business. Management remains focused on strengthening Aon and uniting the firm with one portfolio of capability enabled by data and analytics and one operating model to deliver additional insight, connectivity, and efficiency.
Financial Results
The following is a summary of our 2023 financial results:
Revenue increased $897 million, or 7%, to $13.4 billion in 2023 compared to 2022, reflecting 7% organic revenue growth and a 2% favorable impact from fiduciary investment income, partially offset by a 2% unfavorable impact from acquisitions, divestitures and other.
Operating expenses increased $781 million, or 9%, to $9.6 billion in 2023 compared to 2022 due primarily to an increase in expense associated with 7% organic revenue growth, investments in long-term growth, a $197 million charge in connection with certain accrued actual or anticipated legal settlement expenses, and $135 million of expenses related to the Accelerating Aon United Restructuring Program.
Operating margin decreased to 28.3% in 2023 from 29.4% in 2022. The decrease was driven by an increase in operating expenses as listed above.
Due to the factors set forth above, Net income was $2.6 billion in 2023, a decrease of $18 million, or 1%, from 2022.
Diluted earnings per share increased 3% to $12.51 per share during the twelve months of 2023 compared to $12.14 per share for the prior year period.
Cash flows provided by operating activities was $3.4 billion in 2023, an increase of $216 million, or 7%, from $3.2 billion in 2022, reflecting strong operating income growth and overall working capital optimization, partially offset by higher cash tax payments and a negative impact to working capital due to temporary invoicing delays associated with the implementation of a new system.
We focus on four key metrics not presented in accordance with U.S. GAAP that we communicate to shareholders: organic revenue growth, adjusted operating margin, adjusted diluted earnings per share, and free cash flow. These non-GAAP metrics should be viewed in addition to, not instead of, our Consolidated Financial Statements. The following is our measure of performance against these four metrics for 2023:
Organic revenue growth, a non-GAAP measure defined under the caption “Review of Consolidated Results — Organic Revenue Growth,” was 7% in 2023, compared to 6% organic growth in the prior year period.
Adjusted operating margin, a non-GAAP measure defined under the caption “Review of Consolidated Results — Adjusted Operating Margin,” was 31.6% in 2023, compared to 30.8% in the prior year period. The increase in adjusted operating margin primarily reflects 7% organic revenue growth and higher fiduciary investment income, partially offset by increased expenses and investments in long-term growth.
Adjusted diluted earnings per share, a non-GAAP measure defined under the caption “Review of Consolidated Results — Adjusted Diluted Earnings per Share,” was $14.14 per share in 2023, an increase of $0.75 per share, or 6%, from $13.39 per share in 2022. The increase in adjusted diluted earnings per share primarily reflects strong operational performance and effective capital management, highlighted by $2.7 billion of share repurchase during 2023.
Free cash flow, a non-GAAP measure defined under the caption “Review of Consolidated Results — Free Cash Flow,” was $3.2 billion in 2023, an increase of $160 million, or 5%, from $3.0 billion in 2022, reflecting an increase in Cash flows from operations, partially offset by a $56 million increase in capital expenditures.
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ENVIRONMENTAL, SOCIAL, AND GOVERNANCE
For many companies, the management of ESG risks and opportunities has become increasingly important, and ESG-related challenges, such as extreme weather events, supply chain disruptions, cyber events, regulatory changes, ongoing public health impacts, and the increased focus on workforce resilience in various work environments, continue to create volatility and uncertainty for our clients. At Aon, helping clients manage risk - including ESG risk - is at the core of what we do. We offer a wide range of risk assessment, consulting, and advisory solutions, many of which are significant parts of our core business offerings, designed to address and manage ESG issues for clients, and to enable our clients to create more sustainable value. We see significant opportunity in enhancing our impact and delivering innovative client solutions on ESG matters.
DEFINITIVE ACQUISITION AGREEMENT
On December 19, 2023, Aon entered into a definitive agreement with NFP and the NFP seller, where Aon will acquire NFP for an aggregate purchase price of approximately $7 billion in cash and approximately 20,000,000 class A ordinary shares, nominal value of $0.01, in capital of Aon. The Company expects to fund the cash portion of the consideration with approximately $7 billion of new debt, with $5 billion raised in advance of the closing date and $2 billion raised at close of the acquisition. The acquisition is expected to be completed by mid-2024, subject to satisfaction or waiver of the closing conditions set forth in the Merger Agreement, including applicable regulatory approval.
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REVIEW OF CONSOLIDATED RESULTS
Summary of Results
Our consolidated results are as follow (in millions, except per share data):
Years Ended December 31
202320222021
Revenue   
Total revenue$13,376 $12,479 $12,193 
Expenses   
Compensation and benefits6,902 6,477 6,738 
Information technology534 509 477 
Premises294 289 327 
Depreciation of fixed assets167 151 179 
Amortization and impairment of intangible assets89 113 147 
Other general expense1,470 1,271 2,235 
Accelerating Aon United Program expenses135 — — 
Total operating expenses9,591 8,810 10,103 
Operating income3,785 3,669 2,090 
Interest income31 18 11 
Interest expense(484)(406)(322)
Other income (expense)(163)(125)152 
Income before income taxes3,169 3,156 1,931 
Income tax expense541 510 623 
Net income2,628 2,646 1,308 
Less: Net income attributable to noncontrolling interests64 57 53 
Net income attributable to Aon shareholders$2,564 $2,589 $1,255 
Diluted net income per share attributable to Aon shareholders$12.51 $12.14 $5.55 
Weighted average ordinary shares outstanding - diluted205.0 213.2 226.1 

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Consolidated Results for 2023 Compared to 2022
Revenue
Total revenue increased $897 million, or 7%, to $13.4 billion in 2023, compared to $12.5 billion in 2022. The increase was driven by 7% organic revenue growth and a 2% favorable impact from fiduciary investment income, partially offset by a 2% unfavorable impact from acquisitions, divestitures, and other.
Commercial Risk Solutions revenue increased $328 million, or 5%, to $7.0 billion in 2023, compared to $6.7 billion in 2022. Organic revenue growth was 5% in 2023, reflecting growth across all major geographies, driven by strong retention, management of the renewal book, and net new business generation. Growth in retail brokerage was highlighted by double-digit growth in Asia and the Pacific, driven by continued strength in core P&C. The U.S. grew modestly driven by strength in core areas of property, casualty, and construction, partially offset by the impact of external M&A and IPO activity. On average globally, exposures and pricing were positive, resulting in modestly positive market impact.
Reinsurance Solutions revenue increased $291 million, or 13%, to $2.5 billion in 2023, compared to $2.2 billion in 2022. Organic revenue growth was 10% in 2023 driven by strong retention and net new business generation, as well as strong growth in core Reinsurance. In addition, market impact was modestly positive overall.
Health Solutions revenue increased $209 million, or 9%, to $2.4 billion in 2023, compared to $2.2 billion in 2022. Organic revenue growth was 10% in 2023, reflecting strong growth globally in core health and benefits brokerage, driven by net new business generation and management of the renewal book. Strength in health and benefits included growth in advisory work related to wellbeing and resilience. Results also reflect double-digit growth in Consumer Benefits Solutions and strong growth in Talent.
Wealth Solutions revenue increased $64 million, or 5%, to $1.4 billion in 2023, compared to $1.4 billion in 2022. Organic revenue growth was 4% in 2023 reflecting growth in Retirement, driven by advisory demand and project-related work related to pension de-risking and ongoing impact of regulatory changes. In Investments, a decrease in AUM-based delegated investment management revenue due to debt and equity market movements was partially offset by higher advisory demand and project-related work.
Compensation and Benefits
Compensation and benefits increased $425 million, or 7%, in 2023 compared to 2022. The increase was primarily driven by an increase in expense associated with 7% organic revenue growth.
Information Technology
Information technology, which represents costs associated with supporting and maintaining our infrastructure, increased $25 million, or 5%, in 2023 compared to 2022. The increase was primarily driven by ongoing investments in Aon Business Services-enabled technology platforms and technology to drive long-term growth and continued investment in core infrastructure and security.
Premises
Premises, which represents the cost of occupying offices in various locations throughout the world, increased $5 million, or 2%, in 2023 compared to 2022.
Depreciation of Fixed Assets
Depreciation of fixed assets primarily relates to software, leasehold improvements, furniture, fixtures and equipment, computer equipment, buildings, and automobiles. Depreciation of fixed assets increased $16 million, or 11%, in 2023 compared to 2022, due primarily to ongoing investments in Aon Business Services-enabled technology platforms to drive long-term growth.
Amortization and Impairment of Intangible Assets
Amortization and impairment of intangibles primarily relates to finite-lived customer-related and contract-based, technology, and tradename assets. Amortization and impairment of intangibles decreased $24 million, or 21%, in 2023 compared to 2022 due primarily to a decrease associated with assets held for sale in 2023 as part of ongoing portfolio management and assets fully amortized in the prior year period.
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Other General Expense
Other general expenses increased $199 million, or 16%, in 2023 compared to 2022. The increase was due primarily to a $197 million charge in connection with certain accrued actual or anticipated legal settlement expenses.
Accelerating Aon United Program Expenses
Accelerating Aon United Program expenses were $135 million in 2023, reflecting restructuring charges associated with the Program announced in the third quarter of 2023, relating to workforce optimization, asset impairments, and technology and other costs.
Interest Income
Interest income represents income earned, net of expense, on operating cash balances and other income-producing investments. It does not include interest earned on funds held on behalf of clients. Interest income was $31 million in 2023, an increase of $13 million, or 72%, from 2022, reflecting higher interest rates.
Interest Expense
Interest expense, which represents the cost of our debt obligations, was $484 million in 2023, an increase of $78 million, or 19%, from 2022. The increase was driven primarily by an overall increase in total debt and higher interest rates.
Other Income (Expense)
Other expense was $163 million in 2023, which primarily reflects an expense from the unfavorable impact of exchange rates on the remeasurement of assets and liabilities in non-functional currencies and a non-cash net periodic pension cost. Other expense was $125 million in 2022, primarily reflecting a non-cash pension settlement charge of $170 million, partially offset by gains from sale of businesses.
Income before Income Taxes
Income before income taxes was flat at $3.2 billion in 2023, compared to the prior year period.
Income Taxes
The effective tax rate on net income was 17.1% in 2023 and 16.2% in 2022. The 2023 tax rate was primarily driven by the geographical distribution of income and certain discrete items, including the tax benefits associated with the release of a valuation allowance and share-based payments.
The 2022 tax rate was primarily driven by the geographical distribution of income and certain discrete items, primarily the favorable impacts of share-based payments.
Ireland, the U.K., and many E.U. member states, among others, have enacted legislation to implement the global minimum tax that are consistent with the OECD’s proposed Pillar Two tax regime. There remains significant uncertainty, however, as to how Ireland’s Pillar Two tax regime and the OECD’s past and potentially future Pillar Two guidance will ultimately apply to the Company. The Company is currently evaluating the potential impact that this may have on its global effective tax rate, results of operations, cash flows, and financial condition beginning in 2024.
Net Income Attributable to Aon Shareholders
Net income attributable to Aon shareholders decreased $25 million to $2.6 billion, or $12.51 per diluted share, in 2023, compared to $2.6 billion, or $12.14 per diluted share, in 2022.
Consolidated Results for 2022 Compared to 2021
We have elected not to include a discussion of our consolidated results for 2022 compared to 2021 in this report in reliance upon Instruction 1 to Item 303(b) of Regulation S-K. This discussion can be found in our Annual Report on Form 10-K for the year ended December 31, 2022, which was filed with the SEC on February 17, 2023.
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Non-GAAP Metrics
In our discussion of consolidated results, we sometimes refer to certain non-GAAP supplemental information derived from consolidated financial information specifically related to organic revenue growth, adjusted operating margin, adjusted diluted earnings per share, adjusted net income attributable to Aon shareholders, adjusted net income per share, other income (expense), as adjusted, adjusted effective tax rate, free cash flow, and the impact of foreign exchange rate fluctuations on operating results. Management believes that these measures provide helpful supplemental information that enables investors to make meaningful period-to-period comparisons. Management also uses these measures to assess operating performance and performance for compensation. This non-GAAP supplemental information should be viewed in addition to, not instead of, our Consolidated Financial Statements.
Organic Revenue Growth
We use supplemental information related to organic revenue growth to help us and our investors evaluate business growth from ongoing operations. Organic revenue growth is a non-GAAP measure that includes the impact of certain intercompany activity and excludes the impact of changes in foreign exchange rates, fiduciary investment income, acquisitions, divestitures (including held for sale disposal groups), transfers between revenue lines, and gains or losses on derivatives accounted for as hedges. This supplemental information related to organic revenue growth represents a measure not in accordance with U.S. GAAP and should be viewed in addition to, not instead of, our Consolidated Financial Statements. Industry peers provide similar supplemental information about their revenue performance, although they may not make identical adjustments. A reconciliation of this non-GAAP measure to the reported Total revenue is as follows (in millions, except percentages):
 Years Ended
December 31, 2023December 31, 2022% Change
Less: Currency Impact (1)
Less: Fiduciary Investment Income (2)
Less: Acquisitions, Divestitures & Other
Organic Revenue Growth (3)
Revenue      
Commercial Risk Solutions$7,043 $6,715 %— %%(2)%%
Reinsurance Solutions2,481 2,190 13 (1)— 10 
Health Solutions2,433 2,224 — — (1)10 
Wealth Solutions1,431 1,367 — — 
Elimination(12)(17)N/AN/AN/AN/AN/A
Total revenue$13,376 $12,479 %— %%(2)%%
 Years Ended
December 31, 2022December 31, 2021% Change
Less: Currency Impact (1)
Less: Fiduciary Investment Income (2)
Less: Acquisitions, Divestitures & Other
Organic Revenue Growth (3)
Revenue      
Commercial Risk Solutions$6,715 $6,635 %(4)%%(2)%%
Reinsurance Solutions2,190 1,997 10 (3)
Health Solutions2,224 2,154 (3)— (2)
Wealth Solutions1,367 1,426 (4)(5)— (2)
Elimination(17)(19)N/AN/AN/AN/AN/A
Total revenue$12,479 $12,193 %(4)%%(1)%%
(1)Currency impact represents the effect on prior year period results if they were translated at current period foreign exchange rates.
(2)Fiduciary investment income for the years ended December 31, 2023, 2022, and 2021 was $274 million, $76 million, and $8 million, respectively.
(3)Organic revenue growth includes the impact of certain intercompany activity and excludes the impact of changes in foreign exchange rates, fiduciary investment income, acquisitions, divestitures (including held for sale disposal groups, which had a 1% favorable impact on total organic revenue growth for the year-ended December 31, 2023), transfers between revenue lines, and gains or losses on derivatives accounted for as hedges.

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Adjusted Operating Margin
We use adjusted operating margin as a non-GAAP measure of core operating performance of the Company. Adjusted operating margin excludes the impact of certain items, as listed below, because management does not believe these expenses reflect our core operating performance. This supplemental information related to adjusted operating margin represents a measure not in accordance with U.S. GAAP, and should be viewed in addition to, not instead of, our Consolidated Financial Statements.
A reconciliation of this non-GAAP measure to reported operating margins is as follows (in millions, except percentages):
Years Ended December 31
20232022
Revenue $13,376 $12,479 
Operating income$3,785 $3,669 
Amortization and impairment of intangible assets 89 113 
Accelerating Aon United Program expenses (1)
135 — 
Legal settlements (2)
197 58 
Transaction costs (3)
17 — 
Operating income - as adjusted$4,223 $3,840 
Operating margin28.3 %29.4 %
Operating margin - as adjusted31.6 %30.8 %
(1)Total charges related to the Program are expected to include technology-related costs to facilitate streamlining and simplifying operations, headcount reduction costs, and costs associated with asset impairments, including real estate consolidation costs.
(2)In the fourth quarter of 2023, Aon recognized actual and anticipated legal settlement expenses in connection with transactions for which capital was arranged by a third party, Vesttoo Ltd. primarily in the form of letters of credit from third party banks that are alleged to have been fraudulent. Certain actual or anticipated legal settlements expenses totaling $197 million have been recognized in the current period, where certain potentially meaningful amounts may be recoverable in future periods. Additionally, a $58 million charge was recognized in the second quarter of 2022 with certain other legal settlements reached in matters unrelated to Vesttoo.
(3)In the fourth quarter of 2023, we entered into a definitive agreement to acquire NFP. As part of the definitive agreement, certain transaction costs were incurred including advisory, legal, accounting, and other professional or consulting fees required to complete the acquisition.
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Adjusted Diluted Earnings per Share
We use adjusted diluted earnings per share as a non-GAAP measure of our core operating performance. Adjusted diluted earnings per share excludes the impact of certain items, as listed below, because management does not believe these expenses are the best indicators of our core operating performance. This supplemental information related to adjusted diluted earnings per share represents a measure not in accordance with U.S. GAAP and should be viewed in addition to, not instead of, our Consolidated Financial Statements.
A reconciliation of this non-GAAP measure to reported diluted earnings per share is as follows (in millions, except per share data and percentages):
Year Ended December 31, 2023
U.S. GAAPAdjustmentsNon-GAAP Adjusted
Operating income$3,785 $438 $4,223 
Interest income31 — 31 
Interest expense(484)— (484)
Other income (expense) (1)
(163)27 (136)
Income before income taxes 3,169 465 3,634 
Income tax expense (2)
541 130 671 
Net income2,628 335 2,963 
Less: Net income attributable to noncontrolling interests64 — 64 
Net income attributable to Aon shareholders$2,564 $335 $2,899 
Diluted net income per share attributable to Aon shareholders$12.51 $1.63 $14.14 
Weighted average ordinary shares outstanding — diluted205.0 — 205.0 
Effective tax rates (2)
17.1 %18.5 %
Year Ended December 31, 2022
U.S. GAAPAdjustmentsNon-GAAP Adjusted
Operating income $3,669 $171 $3,840 
Interest income18 — 18 
Interest expense(406)— (406)
Other income (expense) (3)
(125)170 45 
Income before income taxes 3,156 341 3,497 
Income tax expense (2)
510 75 585 
Net income2,646 266 2,912 
Less: Net income attributable to noncontrolling interests57 — 57 
Net income attributable to Aon shareholders$2,589 $266 $2,855 
Diluted net income per share attributable to Aon shareholders$12.14 $1.25 $13.39 
Weighted average ordinary shares outstanding — diluted213.2 — 213.2 
Effective tax rates (2)
16.2 %16.7 %
(1)To further our pension de-risking strategy, we settled certain pension obligations in the Netherlands through the purchase of annuities, where certain pension assets were liquidated to purchase the annuities. A non-cash settlement charge totaling $27 million was recognized in the second quarter of 2023, which is excluded from Other income (expense) - as adjusted.
(2)Adjusted items are generally taxed at the estimated annual effective tax rate, except for the applicable tax impact associated with the anticipated sale of certain assets and liabilities classified as held for sale, certain pension and legal settlements, AAU Program expenses, and certain transaction costs and other charges related to the definitive agreement to acquire NFP, which are adjusted at the related jurisdictional rate.
(3)To further its pension de-risking strategy the Company purchased an annuity for portions of its U.S. pension plans that will settle certain obligations. A non-cash settlement charge totaling $170 million was recognized in the fourth quarter of 2022, which is excluded from Other income (expense) - as adjusted.

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Free Cash Flows
We use free cash flow, defined as cash flow provided by operations minus capital expenditures, as a non-GAAP measure of our core operating performance and cash generating capabilities of our business operations. This supplemental information related to free cash flow represents a measure not in accordance with U.S. GAAP and should be viewed in addition to, not instead of, the Consolidated Financial Statements. Management believes the supplemental information related to free cash flow is helpful to investors when evaluating our operating performance and liquidity results. The use of this non-GAAP measure does not imply or represent the residual cash flow for discretionary expenditures. A reconciliation of this non-GAAP measure to cash flow provided by operations is as follows (in millions):
Years Ended December 31
20232022
Cash provided by operating activities$3,435 $3,219 
Capital expenditures(252)(196)
Free cash flows$3,183 $3,023 
Impact of Foreign Currency Exchange Rate Fluctuations
Because we conduct business in more than 120 countries and sovereignties, foreign currency exchange rate fluctuations have a significant impact on our business. Foreign currency exchange rate movements may be significant and may distort true period-to-period comparisons of changes in revenue or pretax income. Therefore, to give financial statement users meaningful information about our operations, we have provided an illustration of the impact of foreign currency exchange rate fluctuations on our financial results. The methodology used to calculate this impact isolates the impact of the change in currencies between periods by translating the prior year’s revenue, expenses, and net income using the current year’s foreign currency exchange rates.
Currency fluctuations had an unfavorable impact of $0.17 on earnings per diluted share during the year ended December 31, 2023 if prior year period results were translated at current period foreign exchange rates. Currency fluctuations had an unfavorable impact of $0.33 on earnings per diluted share during the year ended December 31, 2022, if 2021 results were translated at 2022 rates.
Currency fluctuations had an unfavorable impact of $0.17 on adjusted earnings per diluted share during the year ended December 31, 2023 if prior year period results were translated at current period foreign exchange rates. Currency fluctuations had an unfavorable impact of $0.44 on adjusted earnings per diluted share during the year ended December 31, 2022, if 2021 results were translated at 2022 rates. These translations are performed for comparative and illustrative purposes only and do not impact the accounting policies or practices for amounts included in our Financial Statements.
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LIQUIDITY AND FINANCIAL CONDITION
Liquidity
Executive Summary
We believe that our balance sheet and strong cash flow provide us with adequate liquidity. Our primary sources of liquidity in the near-term include cash flows provided by operations and available cash reserves; primary sources of liquidity in the long-term include cash flows provided by operations, debt capacity available under our credit facilities, and capital markets. Our primary uses of liquidity are operating expenses and investments, capital expenditures, acquisitions, share repurchases, pension obligations, shareholder dividends, and Accelerating Aon United Program cash charges. We believe that cash flows from operations, available credit facilities, available cash reserves, and the capital markets will be sufficient to meet our liquidity needs, including cash requirements to close our acquisition of NFP, principal and interest payments on debt obligations, capital expenditures, pension contributions, and anticipated working capital requirements in the next twelve months and over the long-term.
Cash on our balance sheet includes funds available for general corporate purposes, as well as amounts restricted as to their use. Funds held on behalf of clients in a fiduciary capacity are segregated and shown together with uncollected insurance premiums and claims in Fiduciary assets in the Consolidated Statements of Financial Position, with a corresponding amount in Fiduciary liabilities.
In our capacity as an insurance broker or agent, we collect premiums from insureds and, after deducting our commission, remit the premiums to the respective insurance underwriters. We also collect claims or refunds from underwriters on behalf of insureds, which are then returned to the insureds. Unremitted insurance premiums and claims are held by us in a fiduciary capacity. The levels of funds held on behalf of clients and liabilities can fluctuate significantly depending on when we collect the premiums, claims, and refunds, make payments to underwriters and insureds, and collect funds from clients and make payments on their behalf, and upon the impact of foreign currency movements. Funds held on behalf of clients, because of their nature, are generally invested in highly liquid securities with highly rated, credit-worthy financial institutions. Fiduciary assets include funds held on behalf of clients comprised of cash and cash equivalents of $6.9 billion and $6.4 billion at December 31, 2023 and 2022, respectively, and fiduciary receivables of $9.4 billion and $9.5 billion at December 31, 2023 and 2022, respectively. While we earn investment income on the funds held in cash and money market funds, the funds cannot be used for general corporate purposes.
We maintain multi-currency cash pools with third-party banks in which various Aon entities participate. Individual Aon entities are permitted to overdraw on their individual accounts provided the overall global balance does not fall below zero. At December 31, 2023, non-U.S. cash balances of one or more entities may have been negative; however, the overall balance was positive.
The following table summarizes our Cash and cash equivalents, Short-term investments, and Fiduciary assets as of December 31, 2023 (in millions):
 Statement of Financial Position Classification 
Asset TypeCash and cash
equivalents
Short-term
investments
Fiduciary
assets
Total
Certificates of deposit, bank deposits, or time deposits$778 $— $4,066 $4,844 
Money market funds— 369 2,835 3,204 
Cash, Short-term investments, and funds held on behalf of clients778 369 6,901 8,048 
Fiduciary receivables— — 9,406 9,406 
Total
$778 $369 $16,307 $17,454 

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Cash and cash equivalents and funds held on behalf of clients, including $43 million of cash and cash equivalents and funds held on behalf of clients classified as held for sale, increased $646 million in 2023 compared to 2022. A summary of our cash flows provided by and used for operating, investing, and financing activities is as follows (in millions):
 Years Ended December 31
20232022
Cash provided by operating activities$3,435 $3,219 
Cash provided by (used for) investing activities$(188)$(449)
Cash used for financing activities$(2,865)$(1,790)
Effect of exchange rates on cash and cash equivalents and funds held on behalf of clients$264 $(549)
Net increase in cash and cash equivalents and funds held on behalf of clients$646 $431 
Operating Activities
Net cash provided by operating activities during the year ended December 31, 2023 were $3.4 billion, an increase of $216 million compared to $3.2 billion of Cash flows provided by operating activities in the prior year. This amount represents Net income reported, generally adjusted for gains from sales of businesses, losses from sales of businesses, share-based compensation expense, depreciation expense, amortization and impairments, and other non-cash income and expenses, including pension settlement charges. Adjustments also include changes in working capital, that relate primarily to the timing of payments of accounts payable and accrued liabilities, collection of receivables, and payments for Accelerating Aon United Program expenses.
Pension Contributions
Pension contributions were $50 million for the year ended December 31, 2023, as compared to $59 million for the year ended December 31, 2022. In 2024, we expect to contribute approximately $68 million in cash to our pension plans, including contributions to non-U.S. pension plans, which are subject to changes in foreign exchange rates.
Accelerating Aon United Program Expenses
In the third quarter of 2023, we initiated the Accelerating Aon United Program (the “Program”) with the purpose of streamlining our technology infrastructure, optimizing our leadership structure and resource alignment, and reducing the real estate footprint to align to our hybrid working strategy. The Program will include technology-related costs to facilitate streamlining and simplifying operations, headcount reduction costs, and costs associated with asset impairments, including real estate consolidation costs.
Program charges are recognized within Accelerating Aon United Program expenses on the accompanying Consolidated Statements of Income and consists of the following cost activities:
Technology and other – includes costs associated with actions taken to rationalize applications, such as contract termination fees and other non-capitalizable costs associated with Program initiatives, which include professional service fees.
Workforce optimization – includes costs associated with headcount reduction and other separation-related costs.
Asset impairments – includes costs associated with impairment of assets, as they are identified, including ROU lease assets, leasehold improvements, and other capitalized assets no longer providing economic benefit.
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The changes in the Company’s liabilities for the Program as of December 31, 2023 are as follows (in millions):
Technology and otherWorkforce optimizationAsset impairmentsTotal
Liability Balance as of January 1, 2023$— $— $— $— 
Charges14 103 18 135 
Cash payments— (13)— (13)
Foreign currency translation and other— — 
Non-cash charges— (5)(18)(23)
Liability balance as of December 31, 2023
$14 $86 $— $100 
Total costs incurred from inception to date$14 $103 $18 $135 
The Program is currently expected to result in cumulative costs of approximately $1,000 million, consisting of approximately $900 million of cash charges and approximately $100 million of non-cash charges. The Program is estimated to generate annualized expense savings of approximately $350 million by the end of 2026, largely benefiting Compensation and benefits, Information technology, and Premises on the Consolidated Statements of Income. For the year ended December 31, 2023, total Program costs incurred were $135 million. The Company expects to continue to review the implementation of elements of the Program throughout the course of the Program and, therefore, there may be changes to expected timing, estimates of expected costs and related savings. We estimate that expense savings resulting from Program actions taken in 2023 will begin to be realized in 2024, predominately in Compensation and benefits on the Consolidated Statements of Income.
Investing Activities
Cash flows used for investing activities during the year ended December 31, 2023 were $188 million, a decrease of $261 million compared to $449 million of Cash flows used for investing activities in the prior year. Generally, the primary drivers of cash flows used for investing activities are acquisition of businesses, purchases of short-term investments, capital expenditures, and payments for investments. Generally, the primary drivers of cash flows provided by investing activities are sales of businesses, sales of short-term investments, and proceeds from investments. The gains and losses corresponding to cash flows provided by proceeds from investments and used for payments for investments are primarily recognized in Other income (expense) in the Consolidated Statements of Income.
Short-term Investments
Short-term investments decreased $83 million to $369 million at December 31, 2023 as compared to December 31, 2022. As disclosed in Note 15 “Fair Value Measurements and Financial Instruments” of the Notes to Consolidated Financial Statements contained in Part II, Item 8 of this report, the majority of our investments carried at fair value are money market funds. These money market funds are held throughout the world with various financial institutions. We are not aware of any market liquidity issues that would materially impact the fair value of these investments.
Acquisitions and Dispositions of Businesses
During 2023, the Company completed the acquisition of three businesses. Cash consideration, net of cash and funds held on behalf of clients acquired, was $35 million, which includes $2 million related to acquisitions completed in 2022. During 2023, the Company completed the disposition of two businesses for a $5 million cash inflow, net of cash and funds held on behalf of clients.
During 2022, the Company completed the acquisition of five businesses for consideration of $162 million, net of cash and funds held on behalf of clients, and the disposition of three businesses for an $81 million cash inflow, net of cash and funds held on behalf of clients.
Capital Expenditures
The Company’s additions to fixed assets including capitalized software, which amounted to $252 million in 2023 and $196 million in 2022, primarily related to the refurbishing and modernizing of office facilities, software development costs, and computer equipment purchases. In the current period, we continue to support certain technology projects to drive long-term growth and real estate projects to align with our Smart Working strategy.
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Financing Activities
Cash flows used for financing activities during the year ended December 31, 2023 were $2.9 billion, an increase of $1.1 billion compared to $1.8 billion of Cash flows used for financing activities in the prior year. Generally, the primary drivers of cash flow used for financing activities are repayments of debt, share repurchases, cash paid for employee taxes on withholding shares, dividends paid to shareholders, transactions with noncontrolling interests, and other financing activities, such as collection of or payments for deferred consideration in connection with prior year business acquisitions and divestitures. Generally, the primary drivers of cash flow provided by financing activities are issuances of debt, changes in net fiduciary liabilities, and proceeds from issuance of shares.
Share Repurchase Program
We have a share repurchase program authorized by our Board of Directors. The Repurchase Program was established in April 2012 with $5.0