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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
For the transition period from ______ to ______.

Commission file number 1-15202

W. R. BERKLEY CORPORATION
(Exact name of registrant as specified in its charter)
Delaware 22-1867895
(State or other jurisdiction of incorporation or organization)
 (I.R.S. Employer Identification Number)
475 Steamboat RoadGreenwich,CT06830
(Address of principal executive offices)(Zip Code)
Registrant’s telephone number, including area code: (203629-3000
Securities registered pursuant to Section 12(b) of the Act:
Title of each classTrading Symbol(s)Name of each exchange on which registered
 
Common Stock, par value $.20 per shareWRBNew York Stock Exchange
5.700% Subordinated Debentures due 2058WRB-PENew York Stock Exchange
5.100% Subordinated Debentures due 2059WRB-PFNew York Stock Exchange
4.250% Subordinated Debentures due 2060WRB-PGNew York Stock Exchange
4.125% Subordinated Debentures due 2061WRB-PHNew 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 15(d) of the 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 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 filer
Non-accelerated filerSmaller reporting company
Emerging 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 Act).      Yes      No 
The aggregate market value of the registrant's common stock held by non-affiliates as of June 30, 2023, the last business day of the registrant’s most recently completed second fiscal quarter, was $12,125,876,386.
Number of shares of common stock, $.20 par value, outstanding as of February 15, 2024: 256,548,669
DOCUMENTS INCORPORATED BY REFERENCE
Portions of the Company’s definitive proxy statement, which will be filed with the Securities and Exchange Commission within 120 days after December 31, 2023, are incorporated herein by reference in Part III.

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 Page
PART I
ITEM1.
ITEM1A.
ITEM1B.
ITEM1C.
ITEM2.
ITEM3.
ITEM4.
 
PART II
ITEM5.
ITEM6.RESERVED
ITEM7.
ITEM7A.
ITEM8.
ITEM9.
ITEM9A.
ITEM9B.
ITEM9C.
 
PART III
ITEM10.
ITEM11.
ITEM12.
ITEM13.
ITEM14.
PART IV
ITEM15.
ITEM16.
EX-10.12
EX-21
EX-23
EX-31.1
EX-31.2
EX-32.1
EX-97
EX-101INSTANCE DOCUMENT
EX-101SCHEMA DOCUMENT
EX-101CALCULATION LINKBASE DOCUMENT
EX-101LABELS LINKBASE DOCUMENT
3



EX-101PRESENTATION LINKBASE DOCUMENT
EX-101DEFINITION LINKBASE DOCUMENT
4



SAFE HARBOR STATEMENT
UNDER THE PRIVATE SECURITIES
LITIGATION REFORM ACT OF 1995

    This is a “Safe Harbor” Statement under the Private Securities Litigation Reform Act of 1995. This document may contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Some of the forward-looking statements can be identified by the use of forward-looking words such as “believes,” “expects,” “potential,” “continued,” “may,” “will,” “should,” “seeks,” “approximately,” “predicts,” “intends,” “plans,” “estimates,” “anticipates” or the negative version of those words or other comparable words. Any forward-looking statements contained in this report including statements related to our outlook for the industry and for our performance for the year 2024 and beyond, are based upon our historical performance and on current plans, estimates and expectations. The inclusion of this forward-looking information should not be regarded as a representation by us that the future plans, estimates or expectations contemplated by us will be achieved. They are subject to various risks and uncertainties, including but not limited to:

the cyclical nature of the property casualty industry;
the impact of significant competition, including new entrants to the industry;
the long-tail and potentially volatile nature of the insurance and reinsurance business;
product demand and pricing;
claims development and the process of estimating reserves;
investment risks, including those of our portfolio of fixed maturity securities and investments in equity securities, including investments in financial institutions, municipal bonds, mortgage-backed securities, loans receivable, investment funds, including real estate, merger arbitrage, energy related and private equity investments;
the effects of emerging claim and coverage issues;
the uncertain nature of damage theories and loss amounts, including claims for cyber security-related risks;
natural and man-made catastrophic losses, including as a result of terrorist activities;
the ongoing effects of the COVID-19 pandemic or other potential pandemics;
the impact of climate change, which may alter the frequency and increase the severity of catastrophe events;
general economic and market activities, including inflation, interest rates and volatility in the credit and capital markets;
the impact of conditions in the financial markets and the global economy, and the potential effect of legislative, regulatory, accounting or other initiatives taken in response to it, on our results and financial condition;
cyber security breaches of our information technology systems and the information technology systems of our vendors and other third parties;
foreign currency and political risks relating to our international operations;
our ability to attract and retain key personnel and qualified employees;
continued availability of capital and financing;
the success of our new ventures or acquisitions and the availability of other opportunities;
the availability of reinsurance;
our retention under the Terrorism Risk Insurance Program Reauthorization Act of 2019 ("TRIPRA");
the ability or willingness of our reinsurers to pay reinsurance recoverables owed to us;
other legislative and regulatory developments, including those related to business practices in the insurance industry;
credit risk relating to our policyholders, independent agents and brokers;
changes in the ratings assigned to us or our insurance company subsidiaries by rating agencies;
the availability of dividends from our insurance company subsidiaries;
the effectiveness of our controls to ensure compliance with guidelines, policies and legal and regulatory standards; and
other risks detailed in this Form 10-K and from time to time in our other filings with the Securities and Exchange Commission (“SEC”).
5



We describe these risks and uncertainties in greater detail in Item 1A, Risk Factors. These risks and uncertainties could cause our actual results for the year 2024 and beyond to differ materially from those expressed in any forward-looking statement we make. Any projections of growth in our revenues would not necessarily result in commensurate levels of earnings. Our future financial performance is dependent upon factors discussed elsewhere in this Form 10-K and our other SEC filings. Forward-looking statements speak only as of the date on which they are made.
6



PART I
ITEM 1. BUSINESS
    W. R. Berkley Corporation is an insurance holding company that is among the largest commercial lines writers in the United States and operates worldwide in two segments of the property casualty insurance business:

Insurance - Our Insurance businesses underwrite predominantly commercial insurance business, including excess and surplus lines, admitted lines and specialty personal lines throughout the United States, as well as insurance business in Asia, Australia, Canada, Continental Europe, Mexico, Scandinavia, South America and the United Kingdom.

Reinsurance & Monoline Excess - Our Reinsurance businesses provide facultative and treaty reinsurance in the United States, as well as in the Asia Pacific region, Australia, Continental Europe, South Africa and the United Kingdom. Monoline Excess businesses retain risk solely on an excess basis.
    Our two reporting segments are each composed of individual businesses that serve a market defined by geography, products, services or industry served. Each of our businesses is positioned close to its customer base and participates in a niche market requiring specialized knowledge. This strategy of decentralized operations allows each of our businesses to identify and respond quickly and effectively to changing market conditions and specific customer needs, while capitalizing on the benefits of centralized capital, investment and reinsurance management, and corporate actuarial, financial, enterprise risk management and legal staff support.
    Our business approach is focused on meeting the needs of our customers, maintaining a high quality balance sheet, and allocating capital to our best opportunities. New businesses are started when opportunities are identified and when the right talent and expertise are found to lead a business. Of our 60 businesses, 53 have been organized and developed internally and seven have been added through acquisition.
    Net premiums written, as reported based on United States generally accepted accounting principles (“GAAP”), for each of our reporting segments for each of the past three years were as follows:
Year Ended December 31,
(In thousands)202320222021
Net premiums written:
Insurance$9,657,121 $8,784,146 $7,743,814 
Reinsurance & Monoline Excess 1,297,346 1,219,924 1,119,053 
Total$10,954,467 $10,004,070 $8,862,867 
Percentage of net premiums written:
Insurance88.2 %87.8 %87.4 %
Reinsurance & Monoline Excess 11.8 12.2 12.6 
Total100.0 %100.0 %100.0 %
Thirty-two of our insurance company subsidiaries are rated by A.M. Best Company, Inc. ("A.M. Best") and have financial strength ratings of A+ (Superior) (the second highest rating out of 15 possible ratings). A.M. Best's ratings are based upon factors of concern to policyholders, insurance agents and brokers and are not directed toward the protection of investors. A.M. Best states: “A Best's Financial Strength Rating (FSR) is an independent opinion of an insurer's financial strength and ability to meet its ongoing insurance policy and contract obligations. An FSR is not assigned to specific insurance policies or contracts and does not address any other risk.” A.M. Best reviews its ratings on a periodic basis, and its ratings of the Company's subsidiaries are therefore subject to change.
Our twenty-three insurance company subsidiaries rated by Standard & Poor's (“S&P”) have financial strength ratings of A+ (the fifth highest rating out of twenty-seven possible ratings).
Our Moody's financial strength ratings are A1 for Berkley Insurance Company, Berkley Regional Insurance Company and Admiral Insurance Company (the fifth highest rating out of twenty-one possible ratings).
Our twenty-five insurance company subsidiaries rated by Fitch Ratings ("Fitch") have insurer financial strength ratings of AA- (the fourth highest rating out of twenty-seven possible ratings).
7



The following sections describe our reporting segments and their businesses in greater detail. These businesses underwrite on behalf of one or more affiliated insurance companies within the group. The businesses are identified for descriptive purposes only and are not legal entities, but for marketing purposes may sometimes be referred to individually as "a Berkley company" or collectively as "Berkley companies." Unless otherwise indicated, all references in this Form 10-K to “Berkley,” “we,” “us,” “our,” the “Company” or similar terms refer to W. R. Berkley Corporation together with its subsidiaries and businesses. W. R. Berkley Corporation is a Delaware corporation formed in 1970.
Insurance
Our Insurance businesses underwrite predominantly commercial and specialty personal lines insurance business primarily throughout the United States. Many units offer coverage globally, while others specialize in specific international markets. The Insurance businesses focus on the following general areas:
Excess & Surplus Lines: A number of our businesses are dedicated to the U.S. excess and surplus lines market. They serve a diverse group of customers that often have complex risk or unique exposures that typically fall outside the underwriting guidelines of the standard insurance market. Lines of business underwritten by our excess and surplus lines businesses include premises operations, auto, property, products liability, general liability and professional liability lines. Products are generally distributed through wholesale agents and brokers.
Industry Specialty: Certain other businesses focus on providing specialty coverages to customers within a particular industry that are best served by underwriters and claims professionals with specialized knowledge of that industry. They offer multiple lines of business with policies tailored to address the unique exposures of these industries, often with the flexibility of providing coverages on either an admitted or a non-admitted basis in the U.S., as well as internationally. Each business delivers its products through one or more distribution channels, including retail and wholesale agents, brokers, and managing general agents (MGAs), depending on the customer and the particular risks insured.
Product Specialty: Other businesses specialize in providing specific lines of insurance coverage, such as workers’ compensation or professional liability, to a wide range of customers. They offer insurance products, analytical tools and risk management services such as loss control and claims management that enable clients to manage their risk appropriately. Business is typically written on an admitted basis, although some businesses may offer non-admitted products in the U.S. and offer products internationally. Independent agents and brokers are the primary means of distribution.
Regional: Certain businesses offer standard insurance products and services focused on meeting the specific needs of a geographically differentiated customer base. Key clients are small-to-midsized businesses. These regionally focused businesses provide a broad array of commercial insurance products to customers primarily in 45 states and the District of Columbia and have developed expertise in niches that reflect local economies. They are organized geographically in order to provide them with the flexibility to adapt quickly to local market conditions and customer needs.
In addition, through our non-U.S. insurance businesses, we write business in more than 60 countries worldwide, with branches or offices in 43 cities outside the United States, in Asia, Australia, Canada, Continental Europe, Mexico, Scandinavia, South America and the United Kingdom. In each of our operating territories, we have built decentralized structures that allow products and services to be tailored to each regional customer base. Our businesses are managed by teams of professionals with expertise in local markets and knowledge of regional environments.
In addition to providing insurance products, certain businesses also provide a wide variety of fee-based services, including claims, administrative and consulting services.
Businesses comprising the Insurance segment are as follows:
Acadia Insurance is a Northeast regional property casualty underwriter offering a broad portfolio of products exclusively through local independent agents in Connecticut, Maine, Massachusetts, New Hampshire, New York, Rhode Island and Vermont. In addition to its general offerings, Acadia has specialized expertise in insuring regional industries such as construction, service contractors, lumber, and transportation.
Admiral Insurance provides excess and surplus lines coverage for commercial risks that generally consist of hard-to- place, specialized risks that involve moderate to high degrees of hazard. In both general liability and professional lines, Admiral has a broad line of products to meet the needs of existing as well as emerging opportunities. The distribution of products is limited solely to wholesale brokers.
Berkley Accident and Health underwrites accident and health insurance and reinsurance products in four primary areas: medical stop loss, managed care, special risk and group captive. It has a diversified product and service portfolio serving a range of clients from small employers, health care organizations, and membership groups to Fortune 500 companies.
8



Berkley Agribusiness offers insurance for larger commercial risks across the United States involved in the supply, storage, handling, processing and distribution of commodities related to the agriculture and food industries.     
Berkley Alliance Managers offers tailored insurance coverages and comprehensive risk management solutions designed to enhance profitability and reduce susceptibility to loss in four target markets - Design Professionals, Construction Professionals, Accounting Professionals and miscellaneous non-medical Service Professionals.
Berkley Aspire provides excess and surplus lines coverage on a national basis to small to medium-sized insureds with low to moderate insurance risk. Its product lines include general liability, excess liability and some property and inland marine coverage. It serves a limited distribution channel, including select Berkley business agents.
Berkley Asset Protection provides specialized insurance coverages for fine arts and jewelry exposures to commercial and individual clients.
Berkley Canada underwrites specialty, casualty and surety lines of business on behalf of the Canadian branch of Berkley Insurance Company. It specializes in commercial casualty and professional liability, and offers a broad portfolio of risk products that include commercial general liability, umbrella, professional liability, directors and officers, commercial property and surety, in addition to niche products for specific industries such as technology, life sciences and travel.
Berkley Construction Solutions provides excess liability coverage to residential and commercial contractors on a project or practice basis.
Berkley Custom Insurance focuses on the excess casualty insurance market and offers umbrella and excess liability coverages to clients from the small/middle market to Fortune 1000 companies in target classes of business including construction, manufacturing, retail/wholesale trade, finance, real estate, public entities and oil & gas.
Berkley Cyber Risk Solutions focuses on insurance and risk management products that respond to the changing cyber security vulnerabilities of organizations around the world. It offers specialty commercial cyber insurance coverages on a worldwide basis to clients of all sizes.
Berkley E&S Solutions provides general liability excess and surplus lines coverages for mid-market U.S. companies with generally hard-to-place, specialized risks that involve moderate to high degrees of hazard and require tailored terms, primarily utilizing self-insurance retentions. The distribution of products is highly limited to a small number of individually appointed wholesale brokers.
Berkley Enterprise Risk Solutions provides custom workers' compensation programs to large employers operating in a broad range of industries. Loss sensitive and/or guaranteed cost programs are offered to employers with exposure predominately in California.
Berkley Entertainment underwrites property casualty insurance products, both on an admitted and non-admitted basis, for clients in the entertainment industry and sports-related organizations.
Berkley Environmental underwrites casualty and specialty environmental products for environmental customers including contractors, consultants, property owners and facilities operators.
Berkley Financial Specialists serves the insurance needs of companies predominantly in the financial services sector. Its Berkley Crime division provides crime and fidelity related insurance products for commercial organizations, financial sector businesses and governmental entities on a primary and excess basis. Its Financial Services segment provides management liability and fidelity products to financial institutions, insurance companies and asset management firms.
Berkley Fire & Marine offers a broad range of preferred inland marine and related property risks and services to customers throughout the United States. Products are distributed through independent agents and brokers.
Berkley Healthcare underwrites customized, comprehensive insurance solutions for the full spectrum of healthcare providers. Through Berkley Healthcare Medical Professional, it offers a wide range of medical professional coverages. Through Berkley Healthcare Financial Lines, it offers a comprehensive suite of financial lines coverages.
Berkley Human Services provides property casualty insurance coverages to human services organizations, including nonprofit and for-profit organizations. Its product offerings include traditional primary and excess coverages.
Berkley Industrial Comp specializes in writing workers' compensation insurance for diverse high hazard industries in select states. Its products are distributed by a select group of independent retail agents and wholesale brokers.
Berkley Insurance Asia underwrites specialty commercial insurance coverages to clients in North Asia and Southeast Asia through offices in Hong Kong, Singapore, Labuan and Shanghai.
9



Berkley Insurance Australia underwrites general insurance business in Australia, including professional indemnity insurance for companies of all sizes.
Berkley Latinoamérica provides property, casualty, auto, surety, group life and workers' compensation products and services in its operating territories of Argentina, Brazil, the Caribbean, Colombia, Mexico and Uruguay.
Berkley Life Sciences offers a comprehensive spectrum of property casualty products to the life sciences industry on a global basis, including both primary and excess product liability coverages. It serves pharmaceutical and biotech companies, medical device companies, dietary supplement companies, medical and research related software developers, contract research and manufacturing organizations, research institutions and organizations, and other related businesses.
Berkley Luxury Group provides commercial package insurance programs for high-end cooperative, condominium, and quality rental apartment buildings and upscale restaurants in the New York, New Jersey, Chicago and Washington, D.C. metropolitan markets, as well as other select markets.
Berkley Management Protection offers a modular suite of management liability products for small and middle market companies through a bespoke and easy to use platform tailored to independent agents. The management liability coverages they provide include directors and officers, employment practices, fiduciary, cyber, crime and miscellaneous professional liability.
Berkley Mid-Atlantic Group provides commercial property casualty coverages to a wide variety of businesses in Delaware, the District of Columbia, Maryland, Ohio, Pennsylvania, and Virginia. Focusing on small and middle market accounts, it complements its standard writings with specialized products in areas such as construction.
Berkley Net Underwriters focuses on small and medium-sized commercial risks, using a web-based system to allow producers to quote, bind and service workers' compensation insurance products on behalf of Berkley member insurance companies.
Berkley North Pacific offers preferred insurance products and services to a broad range of small to medium size commercial entities. It operates through independent agents in Idaho, Montana, Oregon, Utah and Washington.
Berkley Offshore Underwriting Managers is a specialist global underwriter of energy and marine risks. Its three divisions provide specialty insurance products in the energy upstream, energy liability and marine sectors.    
Berkley Oil & Gas provides property casualty products and risk services to the United States energy sector. Its customer base includes risks of all sizes that work in the oil patch, including operators, drillers, geophysical contractors, well-servicing contractors, and manufacturers/distributors of oil field products, as well as those in the renewable energy sector.    
Berkley One provides a customizable suite of personal lines insurance solutions including home, condo/co-op, auto, fine art and collectibles, liability, collector vehicle and recreational marine. Berkley One targets high net worth individuals and families with sophisticated risk management needs.
Berkley Product Protection offers a broad product suite, including product liability and product recall and Contamination, to assist clients in the manufacturing, wholesale and import space with their risk management and insurance needs.
Berkley Professional Liability specializes in professional liability insurance for publicly-traded and private entities on a worldwide basis. Its liability coverages include directors and officers, errors and omissions, fiduciary, employment practices, and sponsored insurance agents' errors and omissions. Berkley Transactional, a division of Berkley Professional Liability, underwrites a full suite of transactional insurance products, including representations and warranties insurance, and tax opinion insurance.
Berkley Program Specialists is a program management business offering both admitted and non-admitted insurance support on a nationwide basis for commercial casualty and property program administrators with specialized insurance expertise. Its book is built around blocks of homogeneous business and programs.    
Berkley Public Entity specializes in providing excess coverage and services to individual governmental and scholastic entities and intergovernmental risk sharing groups. Products include general liability, auto liability, law enforcement liability, public officials and educator's legal liability, employment practices liability, incidental medical, property and crime.
Berkley Risk provides at-risk and alternative risk insurance program management services for a broad range of groups and individuals including public entity pools, professional associations, captives and self-insured clients. As a third party administrator, it manages workers’ compensation, liability and property claims nationwide.
10



Berkley Select specializes in underwriting professional liability insurance for law firms and accounting firms, as well as other professional firms and their practices. It also offers executive liability products, including directors and officers liability, employment practices and fiduciary liability, to small to middle market privately held and not-for-profit customers. Berkley Select provides these insurance products on both an admitted and surplus lines basis.    
Berkley Small Business Solutions offers commercial insurance products for small businesses through a modern technology platform that leverages data and analytics. Its initial product offering focuses on preferred risks in the non-fleet transportation market.
Berkley Southeast offers a wide array of commercial lines products in six southeastern states: Alabama, Georgia, Mississippi, North Carolina, South Carolina and Tennessee, specializing in small to mid-sized accounts.
Berkley Specialty Excess provides excess and surplus lines coverages for hard-to-place risks involved in moderate to high degrees of hazard. It focuses on highly specialized risk exposures within specific industry verticals such as the environmental and energy industries. Its predominate focus is on providing excess insurance; however, in some cases it provides highly specialized environmental primary products tailored to the individual risk. Products are distributed through a minimal number of insurance brokers and agents that specialize in these industry verticals.
Berkley Surety provides a full spectrum of surety bonds for construction, environmental and commercial surety accounts in the U.S. and Canada, through an independent agency and broker platform across 19 field locations.    
Berkley Technology Underwriters provides technology error & omission (TE&O) and first party cyber coverage along with traditional package, umbrella and worker's compensation products. TE&O and cyber products provide industry specialization for both domestic and foreign technology, government contracting, telecommunications, digital media, manufacturing and private equity firms.
Carolina Casualty is a national provider of primary commercial insurance products and services to the transportation industry. It underwrites on an admitted basis in all 50 states and the District of Columbia. Its Berkley Prime Transportation business provides primary auto liability, auto physical damage and general liability to a broad array of trucking operations.
Continental Western Group is a Midwest regional property and casualty insurance operation providing underwriting and risk management services to a broad array of regional businesses in thirteen Midwest states. In addition to its generalist portfolio, Continental Western offers specialty underwriting solutions for diversified agriculture, construction, light manufacturing, transportation, volunteer fire departments, rural utilities and public entities.
Gemini Transportation is a national provider of excess liability insurance for various domestic surface transportation businesses, including the railroad industry as well as the trucking, busing and other industries that use rubber-wheeled vehicles for over-the-road use.
Intrepid Direct provides business insurance coverages through a direct distribution model focused on the franchise market, with specialties including the restaurant, garage and fitness industries.
Key Risk specializes in writing workers' compensation insurance for diverse industries including healthcare, human services, transportation, temporary staffing, professional employer organizations and contractors requiring coverage under the United States Longshore and Harbor Workers' Compensation Act (USL&H). Its products are distributed by a select group of independent retail agents and wholesale brokers located throughout the United States.
Nautilus Insurance Group insures excess and surplus lines risks for small to medium-sized commercial risks with low to moderate susceptibility to loss. It writes commercial excess and surplus lines business nationwide and admitted lines commercial business in a limited number of states. A substantial portion of Nautilus' business is written through its close, long-standing network of general agents, who are chosen on a highly selective basis.
Preferred Employers Insurance focuses exclusively on workers' compensation products and services for businesses based in California. It serves thousands of customers covering a broad spectrum of industries throughout the state.    
Union Standard offers preferred commercial property and casualty insurance products and services to a wide range of small to medium size commercial entities with a focus on the construction, farm/ranch, retail and service industries. It operates through independent agents in Arizona, Arkansas, New Mexico, Oklahoma and Texas.
Vela Insurance Services specializes in commercial casualty insurance on an excess and surplus lines basis. Its primary focus is on general liability insurance for construction, manufacturing and general casualty clients as well as products liability and miscellaneous professional liability coverages distributed through wholesale insurance brokers.
11



Verus Specialty Insurance offers tailored casualty, professional liability, and garage coverages, specializing in the excess and surplus lines market. It primarily serves the construction, manufacturing, garage service and professional sectors through a selective wholesale broker network.
W R B Europe is comprised of specialist businesses offering a focused range of insurance products to markets in Continental Europe.
W / R / B Underwriting provides a broad range of insurance products to the Lloyd's marketplace, with a concentration in specialist classes of business including property, professional indemnity and financial lines.
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    The following table sets forth the percentage of gross premiums written by each Insurance business:
 Year Ended December 31,
 202320222021
Acadia Insurance5.3%5.2%5.5%
Admiral Insurance7.06.25.9
Berkley Accident and Health5.35.15.0
Berkley Agribusiness 0.80.80.8
Berkley Alliance Managers2.32.72.8
Berkley Aspire1.20.90.7
Berkley Asset Protection0.91.00.8
Berkley Canada1.01.21.2
Berkley Construction Solutions0.60.4
Berkley Custom Insurance2.93.13.2
Berkley Cyber Risk Solutions0.80.90.8
Berkley E&S Solutions0.1
Berkley Enterprise Risk Solutions0.1
Berkley Entertainment1.71.81.8
Berkley Environmental6.65.65.2
Berkley Financial Specialists0.60.60.6
Berkley Fire & Marine0.90.70.8
Berkley Healthcare 1.51.81.8
Berkley Human Services1.31.11.0
Berkley Industrial Comp0.70.70.8
Berkley Insurance Asia0.80.80.8
Berkley Insurance Australia1.61.71.7
Berkley Latinoamérica 3.22.92.7
Berkley Life Sciences0.50.50.5
Berkley Luxury Group0.70.80.9
Berkley Management Protection0.20.1
Berkley Mid-Atlantic Group0.91.01.3
Berkley Net Underwriters1.92.22.1
Berkley North Pacific0.70.70.7
Berkley Offshore Underwriting Managers1.51.41.5
Berkley Oil & Gas3.03.53.0
Berkley One2.61.81.2
Berkley Product Protection0.30.30.4
Berkley Professional Liability3.85.87.5
Berkley Program Specialists0.91.72.0
Berkley Public Entity0.70.60.6
Berkley Risk0.30.30.2
Berkley Select1.81.82.0
Berkley Small Business Solutions0.2
Berkley Southeast2.32.22.3
Berkley Specialty Excess0.2
Berkley Surety1.11.11.1
Berkley Technology Underwriters0.60.60.6
Carolina Casualty2.12.11.7
Continental Western Group2.62.42.5
Gemini Transportation3.03.13.0
Intrepid Direct 1.51.21.1
Key Risk2.12.22.5
Nautilus Insurance Group4.74.74.5
Preferred Employers Insurance1.01.21.5
Union Standard1.31.51.7
Vela Insurance Services2.62.52.6
Verus Specialty Insurance1.00.80.8
W R B Europe1.11.01.1
W/R/B Underwriting 3.93.64.0
Other1.72.12.11.2
Total100.0%100.0%100.0%
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    The following table sets forth percentages of gross premiums written, by line, by our Insurance operations:
Year Ended December 31,
202320222021
Other liability38.4%37.0%35.6%
Short-tail lines (1)25.123.222.2
Professional liability13.015.517.3
Auto12.712.612.5
Workers' compensation10.811.712.4
  Total100.0%100.0%100.0%
___________________
(1)Short-tail lines include commercial multi-peril (non-liability), inland marine, accident and health, fidelity and surety, boiler    and machinery, high net worth homeowners and other lines.
Reinsurance & Monoline Excess
We provide other insurance companies and self-insureds with assistance in managing their net risk through reinsurance on either a portfolio basis, through treaty reinsurance, or on an individual basis, through facultative reinsurance. Our monoline excess operations solely retain risk on an excess basis.
Businesses comprising the Reinsurance & Monoline Excess segment are as follows:
Berkley Re America provides treaty and facultative reinsurance solutions on a variety of product lines through reinsurance brokers to companies whose primary operations are within the United States and Canada.
Berkley Re Asia Pacific provides property and casualty reinsurance to the Asia Pacific marketplace. With offices in Brisbane, Sydney, Beijing, Labuan and Singapore, each branch focuses on excess of loss reinsurance, targeting both property and casualty treaty and facultative contracts, through multiple distribution channels.
Berkley Re Solutions is a direct casualty facultative reinsurance underwriter serving clients through a nationwide network of regional offices. Its facultative reinsurance products include automatic, semi-automatic and individual risk assumed reinsurance. It also provides its customers with turnkey products such as cyber, employment practices liability insurance ("EPLI"), liquor liability insurance and violent events coverage to help enhance their clients' product offerings, along with underwriting, claims, and actuarial consultation.
Berkley Re UK writes international property casualty treaty and property facultative accounts. Its territorial scope includes reinsured clients domiciled in the United Kingdom, Europe, Africa, the Middle East and the Caribbean.
Lloyd's Syndicate 2791 Participation represents the Company's minority participation in a Lloyd's syndicate that writes a broad range of mainly short-tail classes of business.
Midwest Employers Casualty provides excess workers' compensation insurance products to individual employers, groups and workers' compensation insurance companies across the United States. Its workers' compensation excess of loss products include self-insured excess of loss coverages and large deductible policies. Through its relationship with Berkley Net Underwriters, Midwest Employers Casualty also offers multi-state coverage for group self-insureds. It has developed sophisticated, proprietary analytical tools and risk management services designed to help its insureds lower their total cost of risk.

14



The following table sets forth the percentages of gross premiums written by each Reinsurance & Monoline Excess business:
 Year Ended December 31,
 202320222021
Berkley Re America33.7%34.6%31.2%
Berkley Re Asia Pacific16.015.615.4
Berkley Re Solutions10.212.513.8
Berkley Re UK11.412.813.8
Lloyd's Syndicate 2791 Participation9.46.16.8
Midwest Employers Casualty19.318.419.0
Total100.0%100.0%100.0%

The following table sets forth the percentages of gross premiums written, by line, by our Reinsurance & Monoline Excess operations:
 Year Ended December 31,
 202320222021
Casualty56.4%61.7%61.8%
Property24.419.919.2
Monoline Excess19.218.419.0
   Total100.0%100.0%100.0%

Results by Segment
Summary financial information about our segments is presented on a GAAP basis in the following table:
 Year Ended December 31,
 (In thousands)
202320222021
Insurance  
Revenue$9,961,152 $8,952,493 $7,578,592 
Income before income taxes1,640,438 1,455,658 1,219,798 
Reinsurance & Monoline Excess
Revenue1,481,991 1,386,639 1,203,647 
Income before income taxes438,765 316,527 270,563 
Other (1)
Revenue699,795 827,367 673,227 
Loss before income taxes(324,800)(52,504)(207,456)
Total
Revenue$12,142,938 $11,166,499 $9,455,466 
Income before income taxes$1,754,403 $1,719,681 $1,282,905 
_______________________________________
(1)Represents corporate revenues and expenses, net investment gains and losses, and revenues and expenses from non-insurance businesses that are consolidated for financial reporting purposes.
    





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The table below represents summary underwriting ratios on a GAAP basis for our segments. Loss ratio is losses and loss expenses incurred expressed as a percentage of net premiums earned. Expense ratio is underwriting expenses expressed as a percentage of net premiums earned. Underwriting expenses do not include expenses related to insurance services or unallocated corporate expenses. Combined ratio is the sum of the loss ratio and the expense ratio. The combined ratio represents a measure of underwriting profitability, excluding investment income. A number in excess of 100 indicates an underwriting loss; a number below 100 indicates an underwriting profit:
 Year Ended December 31,
 202320222021
Insurance  
Loss ratio62.3 %61.3 %61.1 %
Expense ratio28.4 27.9 28.3 
Combined ratio90.7 %89.2 %89.4 %
Reinsurance & Monoline Excess
Loss ratio53.8 %61.3 %61.0 %
Expense ratio28.3 28.4 29.7 
Combined ratio82.1 %89.7 %90.7 %
Total
Loss ratio61.3 %61.3 %61.1 %
Expense ratio28.4 28.0 28.5 
Combined ratio89.7 %89.3 %89.6 %

Investments
Investment results, before income taxes, were as follows:
 Year Ended December 31,
(In thousands) 202320222021
Average investments, at cost (1)$26,444,111 $24,438,112 $22,234,975 
Net investment income (1)$1,052,835 $779,185 $671,618 
Percent earned on average investments (1)3.9 %3.2 %3.0 %
Net investment gains$47,042 $202,397 $90,632 
Change in unrealized investment gains (losses) (2)$392,903 $(1,248,128)$(254,939)
_______________________________________
(1)Includes investments, cash and cash equivalents, trading accounts receivable (payable) from brokers and clearing organizations, trading account securities sold but not yet purchased and unsettled purchases.
(2)Represents the change in unrealized investment gains (losses) for available for sale securities recognized in stockholders' equity.
For comparison, the following are the coupon returns for the Barclays U.S. Aggregate Bond Index and the dividend returns for the S&P 500® Index:
 Year Ended December 31,
 202320222021
Barclays U.S. Aggregate Bond Index3.3 %2.7 %2.3 %
S&P 500® Index
2.0 1.3 1.8 
    
The percentages of the fixed maturity portfolio categorized by contractual maturity, based on fair value, on the dates indicated, are set forth below. Actual maturities may differ from contractual maturities because certain issuers may have the right to call or prepay certain obligations.
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 Year Ended December 31,
 202320222021
1 year or less9.2%8.7%9.5%
Over 1 year through 5 years46.247.246.1
Over 5 years through 10 years21.223.425.2
Over 10 years12.211.212.7
Mortgage-backed securities11.29.56.5
Total100.0%100.0%100.0%

At each of December 31, 2023 and 2022, the fixed maturity portfolio, including cash and cash equivalents, had an effective duration of 2.4 years.
Loss and Loss Expense Reserves
To recognize liabilities for unpaid losses, either known or unknown, insurers establish reserves, which is a balance sheet account representing estimates of future amounts needed to pay claims and related expenses with respect to insured events which have occurred. Estimates and assumptions relating to reserves for losses and loss expenses are based on complex and subjective judgments, often including the interplay of specific uncertainties with related accounting and actuarial measurements. Such estimates are also susceptible to change as significant periods of time may elapse between the occurrence of an insured loss, the report of the loss to the insurer, the ultimate determination of the cost of the loss and the insurer’s payment of that loss.
In general, when a claim is reported, claims personnel establish a “case reserve” for the estimated amount of the ultimate payment based upon known information about the claim at that time. The estimate represents an informed judgment based on general reserving practices and reflects the experience and knowledge of the claims personnel regarding the nature and value of the specific type of claim. Reserves are also established on an aggregate basis to provide for losses incurred but not reported (“IBNR”) to the insurer, potential inadequacy of case reserves and the estimated expenses of settling claims, including legal and other fees and general expenses of administrating the claims adjustment process. Reserves are established based upon the then current legal interpretation of coverage provided.
In examining reserve adequacy, several factors are considered in estimating the ultimate economic value of losses. These factors include, among others, historical data, legal developments, changes in social attitudes and economic conditions, including the effects of inflation. The actuarial process relies on the basic assumption that past experience, adjusted judgmentally for the effects of current developments and anticipated trends, is an appropriate basis for predicting future outcomes. Reserve amounts are necessarily based on management’s informed estimates and judgments using currently available data. As additional experience and other data become available and are reviewed, these estimates and judgments may be revised. This may result in reserve increases or decreases that would be reflected in our results in periods in which such estimates and assumptions are changed.
The risk and complexity of estimating loss reserves are greater when economic conditions are uncertain. It is especially difficult to estimate the impact of inflation on loss reserves given the current economic environment and related government actions. Whereas a slowing economy would generally lead to lower inflation or even deflation, increased government spending would generally lead to higher inflation. A change in our assumptions regarding inflation would result in reserve increases or decreases that would be reflected in our earnings in periods in which such assumptions are changed.
Reserves do not represent an exact calculation of liability. Rather, reserves represent an estimate of what management expects the ultimate settlement and claim administration will cost. While the methods for establishing the reserves are well tested over time, some of the major assumptions about anticipated loss emergence patterns are subject to unanticipated fluctuation. These estimates, which generally involve actuarial projections, are based on management’s assessment of facts and circumstances then known, as well as estimates of trends in claims severity and frequency, judicial theories of liability and other factors, including the actions of third parties, which are beyond the Company’s control. These variables are affected by external and internal events, such as inflation and economic volatility, judicial and litigation trends, reinsurance coverage, legislative changes and claim handling and reserving practices, which make it more difficult to accurately predict claim costs. The inherent uncertainties of estimating reserves are greater for certain types of liabilities where long periods of time elapse before a definitive determination of liability is made. Although the loss reserves included in the Company’s financial statements represent management’s best estimates, setting reserves is inherently uncertain and the Company cannot provide assurance that its current reserves will prove adequate in light of subsequent events.
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The Company discounts its liabilities for certain workers’ compensation reserves. The amount of workers’ compensation reserves that were discounted was $1,352 million and $1,464 million at December 31, 2023 and 2022, respectively. The aggregate net discount for those reserves, after reflecting the effects of ceded reinsurance, was $390 million and $416 million at December 31, 2023 and 2022, respectively. At December 31, 2023, discount rates by year ranged from 0.7% to 6.5%, with a weighted average discount rate of 3.5%.
Substantially all discounted workers’ compensation reserves (97% of total discounted reserves at December 31, 2023) are excess workers’ compensation reserves. In order to properly match loss expenses with income earned on investment securities supporting the liabilities, reserves for excess workers’ compensation business are discounted using risk-free discount rates determined by reference to the U.S. Treasury yield curve. These rates are determined annually based on the weighted average rate for the period. Once established, no adjustments are made to the discount rate for that period, and any increases or decreases in loss reserves in subsequent years are discounted at the same rate, without regard to when any such adjustments are recognized. The expected loss and loss expense payout patterns subject to discounting are derived from the Company’s loss payout experience.  
The Company also discounts reserves for certain other long-duration workers’ compensation reserves (representing approximately 3% of total discounted reserves at December 31, 2023), including reserves for quota share reinsurance and reserves related to losses regarding occupational lung disease. These reserves are discounted at statutory rates permitted by the Department of Insurance of the State of Delaware.
To date, known environmental and asbestos claims have not had a material impact on the Company’s operations, because its subsidiaries generally did not insure large industrial companies that are subject to significant environmental or asbestos exposures prior to 1986 when an absolute exclusion was incorporated into standard policy language.
The Company’s net reserves for losses and loss expenses relating to environmental and asbestos claims on policies written before adoption of the absolute exclusion was $17 million and $20 million at December 31, 2023 and 2022, respectively. The estimation of these liabilities is subject to significantly greater than normal variation and uncertainty because it is difficult to make an actuarial estimate of these liabilities due to the absence of a generally accepted actuarial methodology for these exposures and the potential effect of significant unresolved legal matters, including coverage issues, as well as the cost of litigating the legal issues. Additionally, the determination of ultimate damages and the final allocation of such damages to financially responsible parties are highly uncertain.
The table below provides a reconciliation of the beginning of year and end of year property casualty reserves for the indicated years:
(In thousands)202320222021
Net reserves at beginning of year$14,248,879 $12,848,362 $11,620,393 
Net provision for losses and loss expenses:
Claims occurring during the current year (1)6,311,780 5,774,713 4,921,191 
Increase in estimates for claims occurring in prior years (2)29,681 54,511 863 
Loss reserve discount amortization30,681 32,526 31,906 
Total6,372,142 5,861,750 4,953,960 
  Net payments for claims:
Current year1,217,078 1,068,577 887,896 
Prior years3,764,532 3,279,333 2,777,798 
Total4,981,610 4,347,910 3,665,694 
Foreign currency translation22,409 (113,323)(60,297)
Net reserves at end of year15,661,820 14,248,879 12,848,362 
Ceded reserves at end of year3,077,832 2,762,344 2,542,526 
Gross reserves at end of year$18,739,652 $17,011,223 $15,390,888 
Net change in premiums and losses occurring in prior years:
Increase in estimates for claims occurring in prior years (2)$(29,681)$(54,511)$(863)
Retrospective premium adjustments for claims occurring in prior years (3)10,782 18,106 7,510 
Net premium and reserve development on prior years$(18,899)$(36,405)$6,647 
____________________________________
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(1)Claims occurring during the current year are net of loss reserve discounts of $47 million, $35 million and $21 million in 2023, 2022 and 2021, respectively.
(2)The change in estimates for claims occurring in prior years is net of loss reserve discount. On an undiscounted basis, the estimates for claims occurring in prior years decreased by $13 million in 2023, increased by $16 million in 2022, and decreased by $19 million in 2021.
(3)For certain retrospectively rated insurance policies and reinsurance agreements, changes in loss and loss expenses for prior years are offset by additional or return premiums.
    
Also, see Item 7, “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and note 13, Reserves for Losses and Loss Expenses included in our audited consolidated financial statements for further information regarding the changes in estimates for claims occurring in prior years.
A reconciliation between the reserves as of December 31, 2023 as reported in the accompanying consolidated GAAP financial statements and those reported on the basis of statutory accounting principles (“SAP”) in the Company’s U.S. regulatory filings is as follows:
(In thousands)
Net reserves reported in U.S. regulatory filings on a SAP basis$14,954,598 
Reserves for non-U.S. companies780,762 
Loss reserve discounting (1)(80,832)
Ceded reserves3,077,832 
Allowance for expected credit losses on due from reinsurers7,292 
Gross reserves reported in the consolidated GAAP financial statements$18,739,652 
_________________________
(1)For statutory purposes, the Company discounts its workers’ compensation reinsurance reserves at 2.5% as prescribed or permitted by the Department of Insurance of the State of Delaware. In its GAAP financial statements, the Company discounts excess workers’ compensation reserves at the risk-free rate and assumed workers’ compensation reserves at the statutory rate.
Reinsurance
We follow a common industry practice of reinsuring a portion of our exposures and paying to reinsurers a portion of the premiums received on the policies that we write. Reinsurance is purchased principally to reduce net liability on individual risks and to protect against catastrophic losses. Although reinsurance does not legally discharge an insurer from its primary liability for the full amount of the policies, it does make the assuming reinsurer contractually liable to the insurer to the extent of the reinsurance coverage. We monitor the financial condition of our reinsurers and attempt to place our coverages only with substantial, financially sound carriers. As a result, generally the reinsurers who reinsure our casualty insurance must have an A.M. Best rating of “A (Excellent)” or better with at least $1 billion in policyholder surplus and the reinsurers who cover our property insurance must have an A.M. Best rating of “A- (Excellent)” or better with at least $1 billion in policyholder surplus.

Regulation
U.S. Regulation 
Our U.S. insurance subsidiaries are principally regulated by their domiciliary state insurance departments and are subject to varying degrees of regulation and supervision in the other U.S. jurisdictions in which they do business. As of January 1, 2024, there are six domiciliary states related to our U.S. insurance subsidiaries.
Overview. Our domestic insurance subsidiaries are subject to statutes which delegate regulatory, supervisory and administrative powers to state insurance commissioners. This regulation relates to such matters as the standards of solvency which must be met and maintained; the licensing of insurers and their agents; the nature of and limitations on investments; deposits of securities for the benefit of policyholders; approval of certain policy forms and premium rates; periodic examination of the affairs of insurance companies; annual and other reports required to be filed on the financial condition of insurers or for other purposes; establishment and maintenance of reserves for unearned premiums, loss expenses and losses; and requirements regarding numerous other matters. Our property casualty subsidiaries, other than our excess and surplus lines and reinsurance subsidiaries, must generally file all rates with the insurance department of each state in which they operate. Our excess and
surplus lines and reinsurance subsidiaries generally operate free of rate and form regulation.

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Holding Company Statutes. In addition to regulatory supervision of our insurance subsidiaries, we are subject to state statutes governing insurance holding company systems. Under the terms of applicable state statutes, any person or entity desiring to purchase more than a specified percentage (commonly 10%) of our outstanding voting securities would be required to obtain prior regulatory approval of the purchase. Typically, such statutes require that we periodically file information with the appropriate domiciliary state insurance commissioner, including information concerning our capital structure, ownership, financial condition and general business operations.
We must also annually submit to the lead state regulator for our group an “enterprise risk management report” which identifies the activities and circumstances of any affiliated company that might have a material adverse effect on the financial condition of our group or our U.S. licensed insurers.
In addition, all states have adopted changes to the holding company act that authorize U.S. insurance regulators to lead or participate in the group-wide supervision of certain international insurance groups. In November 2019, the International Association of Insurance Supervisors (“IAIS”), an international standard setter, adopted a global framework for the supervision of internationally active insurance groups (“IAIGs”), as discussed below under “International Regulation.” This framework includes a risk-based, group-wide global insurance capital standard (“ICS”), which is undergoing a five-year monitoring period that started in January 2020. We have received notice from Delaware, our lead state insurance regulator, that we may be considered an IAIG. In the event that we are deemed to be an IAIG, we would be subject to international oversight coordinated by the Delaware Department of Insurance.
In the United States, the National Association of Insurance Commissioners (the “NAIC”) has developed a group capital calculation tool that uses a risk-based capital aggregation methodology for all entities in an insurance holding company system. The goal is to provide U.S. regulators with a method to aggregate the available capital and the minimum capital of each entity in a group in a way that applies to all companies regardless of their structure. In 2022, Delaware, our lead state regulator, adopted the NAIC amendments to the model holding company act and regulation that require the ultimate controlling person of an insurer subject to holding company registration to submit the group capital calculation filing annually with its lead state regulator.
All states have adopted the NAIC's Risk Management and Own Risk and Solvency Assessment Model Act (the “ORSA Model Act”), which requires an insurance holding company system’s chief risk officer to submit annually to its lead state insurance regulator an Own Risk and Solvency Assessment Summary Report (“ORSA Report”). The ORSA Report is a confidential internal assessment of the material and relevant risks associated with an insurer’s current business plan and the sufficiency of capital resources to support those risks. Under the ORSA Model Act, as enacted by the states, we are required to:
regularly, no less than annually, conduct an Own Risk and Solvency Assessment to assess the adequacy of our risk management framework, and current and estimated projected future solvency position;
internally document the process and results of the assessment; and
provide an ORSA Report annually to the State of Delaware's Insurance Commissioner.
Cybersecurity Regulations. New York’s cybersecurity regulation applies to financial services institutions authorized by the New York State Department of Financial Services (the “NYDFS”), including our insurance subsidiaries licensed in New York. The regulation requires these entities to assess risks associated with their information systems and establish and maintain a cybersecurity program reasonably designed to protect consumers’ private data and the confidentiality, integrity and availability of the licensee’s information systems. On November 1, 2023, the NYDFS adopted amendments to New York’s cybersecurity regulation, which require additional reporting, governance and oversight measures, and enhanced cybersecurity safeguards to be implemented. The amendments take effect in phases that began in 2023 and continue through 2025.
The NAIC has adopted the Insurance Data Security Model Law (the “Cybersecurity Model Law”) for consideration by state legislatures, which establishes standards for data security, the investigation of cybersecurity events involving the unauthorized access to, or misuse of, certain nonpublic information, and reporting to insurance commissioners. The Cybersecurity Model Law imposes significant regulatory burdens intended to protect the confidentiality, integrity and availability of information systems. As of December 31, 2023, the Cybersecurity Model Law, or a form thereof, had been adopted by several states, including three of our U.S. insurance subsidiaries’ domiciliary states. A drafting note in the Cybersecurity Model Law states that a licensee’s compliance with New York's cybersecurity regulation is intended to constitute compliance with the Cybersecurity Model Law, but compliance remains a state-by-state issue requiring consideration of any State differences in implementation and enforcement of the Cybersecurity Model Law.

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Certain other states have enacted or are considering laws and regulations related to privacy and data security. For example, the California Consumer Privacy Act (“CCPA”), broadly regulates the collection, processing and disclosure of California residents’ personal information, imposes limits on the “sale” of personal information and grants California residents certain rights to, among other things, access and delete data about them in certain circumstances. The CCPA also established a private right of action, with potentially significant statutory damages, whereby businesses that fail to implement reasonable security measures to protect against breaches of personal information could be liable to affected California consumers. California subsequently enacted the California Privacy Rights Act (“CPRA”), which came into full effect in January 2023 and amended the CCPA by imposing additional limitations and obligations with respect to covered businesses’ use and sharing of certain personal data. Compliance with the CCPA/CPRA may increase the cost of providing our products and services in California. An increasing number of U.S. states have adopted, or are considering legislation similar to the CCPA.
Additionally, the NAIC is working on a new Insurance Consumer Privacy Protections Model Law to
reflect the extensive innovations in communications and technology since the adoption of the prior model laws.
We cannot predict the impact, if any, that any current, proposed or future federal or state cybersecurity laws or regulations will have on our business, financial condition or results of operations.
Innovation and Technology. As a result of increased innovation and use of technology in the insurance sector, the NAIC and insurance regulators have been focusing on the use of “big data” techniques, such as artificial intelligence, machine learning and automated decision-making. In December 2023, the NAIC adopted the Model Bulletin on the Use of Artificial Intelligence Systems by Insurers (the “AI Bulletin”). The AI Bulletin may be adopted and issued by state regulators to licensed insurers. In addition to affirming that the use of artificial intelligence must comply with existing state law, the AI Bulletin sets forth regulators’ expectations on how insurers will develop, acquire and use artificial intelligence technologies. In 2024, the NAIC plans to form a new task force to create a regulatory framework for the oversight of insurers’ use of third-party data and models.
The NAIC and state insurance regulators are also focused on addressing unfair discrimination by insurers in the use of consumer data and technology, and certain states have passed laws or are considering action targeting unfair discrimination practices. For example, in 2021 Colorado enacted a law that prohibits insurers from using external consumer data and information sources (“ECDIS”), as well as algorithms or predictive models that use ECDIS, in a way that unfairly discriminates based on race, color, national or ethnic origin, religion, sex, sexual orientation, disability, gender identity or gender expression. In August 2023, Colorado adopted regulations requiring life insurers to adopt a governance and risk management framework for the use of artificial intelligence, machine learning and other technologies that utilize “external consumer data.” It is expected that Colorado will also adopt governance and testing regulations for other lines of insurance, in accordance with the requirements of its 2021 law.
We cannot predict whether states will adopt the AI Bulletin, or what, if any, changes to laws or regulations may be enacted with regard to “big data” or artificial intelligence technologies.
Risk-Based Capital Requirements. The NAIC utilizes a Risk-Based Capital (“RBC”) formula that is designed to measure the adequacy of an insurer's statutory surplus in relation to the risks inherent in its business. The RBC formula develops a risk adjusted target level of adjusted statutory capital by applying certain factors to various asset, premium and reserve items. The NAIC RBC Model Law provides for four incremental levels of regulatory attention for insurers whose surplus is below the calculated RBC target. These levels of attention range in severity from requiring the insurer to submit a plan for corrective action to actually placing the insurer under regulatory control. The RBC of each of our domestic insurance subsidiaries was above the calculated RBC target level as of December 31, 2023. 
Insurance Regulatory Information System. The NAIC also has developed a set of 13 financial ratios for property and casualty insurers referred to as the Insurance Regulatory Information System (“IRIS”). On the basis of statutory financial statements filed with state insurance regulators, the NAIC annually calculates these IRIS ratios to assist state insurance regulators in monitoring the financial condition of insurance companies. The NAIC has established an acceptable range for each of the IRIS financial ratios.
Guaranty Funds. Our U.S. insurance subsidiaries are also subject to assessment by state guaranty funds in states where we transact admitted business when an insurer in a particular jurisdiction has been judicially declared insolvent and the insolvent company's available funds are insufficient to pay policyholders and claimants the amounts to which they are entitled. The protection afforded under a state's guaranty fund to policyholders of the insolvent insurer varies from state to state. Generally, all licensed property casualty insurers are considered to be members of the fund, and assessments are based upon their pro rata share of direct written premiums in that state. The NAIC Post-Assessment Property and Liability Insurance Guaranty Association Model Act, a version of which has been adopted by all states, limits assessments to 2% of an insurer’s subject premiums and permits recoupment of assessments through rate setting. Likewise, several states (or underwriting
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organizations of which our insurance subsidiaries are required to be members) have limited assessment authority with regard to deficits in certain lines of business.
Additionally, state insurance laws and regulations require us to participate in mandatory property-liability “shared market,” “pooling” or similar arrangements that provide certain types of insurance coverage to individuals or others who otherwise are unable to purchase coverage voluntarily provided by private insurers. Shared market mechanisms include assigned risk plans and fair access to insurance requirement or “FAIR” plans. In addition, some states require insurers to participate in reinsurance pools for claims that exceed specified amounts. Our participation in these mandatory shared market or pooling mechanisms generally is related to the amount of our direct writings for the type of coverage written by the specific mechanism in the applicable state. 
Dividends. We receive funds from our insurance company subsidiaries in the form of dividends and management fees for certain management services. Annual dividends in excess of maximum amounts prescribed by state statutes may not be paid without the approval of the insurance commissioner of the state in which an insurance subsidiary is domiciled. See “Management's Discussion and Analysis of Financial Condition and Results of Operations-Liquidity and Capital Resources.” 
Trade Practices. State insurance laws and regulations include numerous provisions governing trade practices and the marketplace activities of insurers, including provisions governing marketing and sales practices, policyholder services, claims management and complaint handling. State regulatory authorities generally enforce these provisions through periodic market conduct examinations.
Investment Regulation. Investments by our domestic insurance companies must comply with applicable laws and regulations which prescribe the kind, quality and concentration of investments. In general, these laws and regulations permit investments in federal, state and municipal obligations, corporate bonds, preferred and common equity securities, mortgage loans, real estate and certain other investments, subject to specified limits and certain other qualifications. Investments that do not comply with these limits and qualifications are deducted in our insurance subsidiaries' calculation of their statutory capital and surplus.
Terrorism Risk Insurance. The Terrorism Risk Insurance Act of 2002 established a Federal program that provides for a system of shared public and private compensation for insured losses resulting from acts of terrorism. Pursuant to the Terrorism Risk Insurance Program Reauthorization Act of 2019 (“TRIPRA”), the program was extended until December 31, 2027.
TRIPRA provides a federal backstop to all U.S. based property and casualty insurers for insurance related losses resulting from any act of terrorism on U.S. soil or against certain U.S. air carriers, vessels or foreign missions. TRIPRA is applicable to almost all commercial lines of property and casualty insurance but excludes auto, burglary and theft, surety, professional liability and farm owners' multi-peril insurance. Insurers with direct commercial property and casualty insurance exposure in the United States are required to participate in the program and make available coverage for certified acts of terrorism. TRIPRA's definition of certified acts includes domestic terrorism. Federal participation will be triggered under TRIPRA when the Secretary of Treasury certifies an act of terrorism.
Under the program, the federal government will pay 80% of an insurer's covered losses in excess of the insurer's applicable deductible. The insurer's deductible is calculated as 20% of earned premium for the prior year for covered lines of commercial property and casualty insurance. Based on our 2023 earned premiums, our aggregate deductible under TRIPRA during 2024 will be approximately $1,464 million. The federal program will not pay losses for certified acts unless such losses exceed $200 million industry-wide for any calendar year. TRIPRA limits the federal government's share of losses at $100 billion for a program year. In addition, an insurer that has satisfied its deductible is not liable for the payment of losses in excess of the $100 billion cap.
Excess and Surplus Lines. The regulation of our U.S. subsidiaries' excess and surplus lines insurance business differs significantly from the regulation of our admitted business. Our surplus lines subsidiaries are subject to the surplus lines regulation and reporting requirements of the jurisdictions in which they are eligible to write surplus lines insurance. Although surplus lines business is generally less regulated than admitted business, principally with respect to rates and policy forms, strict regulations apply to surplus lines placements in the laws of every state and the regulation of surplus lines insurance may undergo changes in the future. Federal or state measures may be introduced to increase the oversight of surplus lines insurance in the future.
Climate Change and Financial Risks. The NAIC and state insurance regulators continue to evaluate issues related to the management of climate risk. In 2022, the NAIC adopted a new standard for insurance companies to report their climate-related risks as part of its annual Climate Risk Disclosure Survey, which applies to insurers that meet the reporting threshold of $100 million in U.S. direct premium and are licensed in one of the participating jurisdictions. The NYDFS’s 2020 circular letter, which applies to our insurance subsidiaries licensed in New York, states that regulated insurers are expected to integrate
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financial risks related to climate change into their governance frameworks, risk management processes, business strategies and scenario analysis, and develop their approach to climate-related financial disclosure. For example, an insurer should designate a board member or board committee, as well as a senior management function, to oversee the management of financial risks associated with climate change. The NYDFS also adopted an amendment to the regulation governing enterprise risk management, which applies to our insurance subsidiaries licensed in New York, that requires an insurance group's enterprise risk management function to address certain additional risks, including climate change risk.
In addition, the Federal Insurance Office (the “FIO”) is authorized to monitor the U.S. insurance industry under the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010 (the “Dodd-Frank Act”), as discussed below under “Federal Regulation.” Pursuant to this statutory authority, the FIO is assessing how the insurance sector may mitigate climate risks and help achieve national climate-related goals. In June 2023, the FIO released a report urging insurance regulators to adopt climate-related risk-monitoring guidance in order to enhance their regulation and supervision of insurers.
Diversity and Corporate Governance.The NAIC and state insurance regulators also continue to evaluate issues related to diversity within the insurance industry, such as the diversity of an insurer’s board of directors and management. In March 2021, the NYDFS issued a circular letter stating that it expects the insurers it regulates, such as our insurance subsidiaries licensed in New York, to make diversity of their leadership a business priority and a key element of their corporate governance, and it includes diversity-related questions in its examination process. In addition, the NAIC is examining practices in the insurance industry in order to determine how barriers are created that disadvantage or discriminate against people of color or historically underrepresented groups. NAIC goals include improving access to different types of insurance products in minority communities, addressing issues related to affordability, and providing guidance to regulators on ways to improve insurance access and the understanding of insurance in underserved communities. See “Human Capital Resources” below.
Federal Regulation. The federal government and its regulatory agencies generally do not directly regulate the business of insurance, although federal initiatives could have an impact on our business in a variety of ways. The Dodd-Frank Act effected sweeping changes to financial services regulation in the United States, and created two new federal government bodies, the FIO and the Financial Stability Oversight Council (the “FSOC”). The FIO does not have general supervisory or regulatory authority over the business of insurance, although it has preemption authority over state insurance laws that conflict with certain international agreements, as discussed below. The FIO also has authority to represent the United States in international insurance matters and is authorized to monitor the U.S. insurance industry and identify potential regulatory gaps that could contribute to systemic risk. The Economic Growth, Regulatory Relief and Consumer Protection Act of 2018 addresses the roles played by federal regulators at international insurance standard-setting forums, and it directs the Director of the FIO and the Board of Governors of the Federal Reserve to support increased transparency at international standard-setting regulatory forums (e.g., the IAIS). These federal regulations also instruct the FIO and the Federal Reserve to achieve consensus positions with the states through the NAIC prior to taking a position on any insurance proposal by a global insurance regulatory forum.
The Dodd-Frank Act authorizes the Secretary of the Treasury and U.S. Trade Representative to enter into international agreements of mutual recognition regarding the prudential regulation of insurance or reinsurance. The U.S. and the European Union ("EU") signed such a covered agreement (the "EU Covered Agreement") in September 2017, which addresses three areas of prudential supervision: reinsurance, group supervision and the exchange of information between the U.S. and EU.
In December 2018, the U.S. Department of the Treasury and the Office of the U.S. Trade Representative entered into a covered agreement with the U.K. (the “U.K. Covered Agreement,” and together with the EU Covered Agreement, the “Covered Agreements”) in anticipation of the U.K.’s exit from the EU. The U.K. Covered Agreement largely reflects the provisions of the EU Covered Agreement and incorporates the same timeframes within it.
Under the Dodd-Frank Act, the FIO has preemption authority over state insurance laws that conflict with the Covered Agreements as of September 1, 2022, such as state credit for reinsurance laws that result in non-U.S. reinsurers subject to the Covered Agreements being treated less favorably than U.S. reinsurers. The NAIC previously adopted amendments to its Credit for Reinsurance Model Law to satisfy the substantive and timing requirements of the Covered Agreements, which amendments have been enacted by all states. On September 30, 2023, the FIO reported that it did not recommend taking any preemption action as a result of inconsistency between the Covered Agreements and state credit for reinsurance laws, although it is still monitoring state measures implementing the NAIC’s revisions to the Credit for Reinsurance Model Law. Under the Covered Agreements, reinsurance collateral requirements no longer apply to qualifying EU and U.K. reinsurers. The amended Credit for Reinsurance Model Law also extends the zero reinsurance collateral provisions in the Covered Agreements to qualified reinsurers domiciled in U.S. jurisdictions that are accredited by the NAIC and to non-U.S. jurisdictions that have not entered into a covered agreement with the U.S. but which the NAIC has identified as “reciprocal jurisdictions” pursuant to the NAIC Qualified Jurisdiction Process.
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We cannot currently predict the impact of these changes to the law or whether any other covered agreements will be successfully adopted, and cannot currently estimate the impact of these changes to the law and any such adopted covered agreements on our business, financial condition or operating results.
The Dodd-Frank Act authorizes the FSOC to designate an insurer as a “systemically important financial institution” or a “non-bank SIFI” if the insurer’s material financial distress could pose a systemic risk to the financial system or the nature or scale of its activities could pose a threat to U.S. financial stability. The FIO can recommend that an insurer be designated as a non-bank SIFI, which would subject the company to Federal Reserve supervision and heightened prudential standards. There are currently no such non-bank SIFIs designated by the FSOC. In November 2023, the FSOC adopted final guidance that establishes a new process for designating certain financial companies as non-bank SIFIs. The revised process is based on the consideration of risk factors set forth in a new analytic framework, which describes how the FSOC intends to monitor a broad range of institutions and activities and respond to potential risks to U.S. financial stability. The financial vulnerabilities that most often contribute to this type of risk include leverage, liquidity risk and maturity mismatch, inadequate risk management, concentration and destabilizing activities. Under the new guidance, the FSOC is no longer required to conduct a cost-benefit analysis and an assessment of the likelihood of a non-bank financial company’s material financial distress before considering the designation of the company. The revised process could have the effect of simplifying and shortening FSOC’s procedures for designating certain financial companies as non-bank SIFIs.
Based upon our current business model and balance sheet, we do not believe that we will be designated by the FSOC as such an institution. Although the potential impact of any future amendments to the Dodd-Frank Act on the U.S. insurance industry is not clear, our business could be affected by changes to the U.S. system of insurance regulation or our designation or the designation of insurers or reinsurers with which we do business as non-bank SIFIs.
Legislative and Regulatory Activity Related to the COVID-19 Pandemic or Other Potential Pandemics. In response to the outbreak of the COVID-19 pandemic in 2020, legislators in several states and in the United States Congress introduced proposals that would have mandated insurance coverage for certain pandemic-related losses, including business interruption losses, or that would have established a federal insurance program for addressing pandemic risk. None of these proposals were enacted. However, there remains some risk that in the event of another pandemic event, whether related to COVID-19 or another contagious disease, Congress could take similar actions. See “Risk Factors — Risks Related to Our Industry — The COVID-19 pandemic materially and adversely affected our results of operations, and, whether as a result of COVID-19's long-term effects, or new or emerging variants, or other potential pandemics, may further materially and adversely affect our results of operations, financial position and liquidity in the future."
International Regulation
Our insurance subsidiaries based in the United Kingdom are regulated by the Prudential Regulation Authority (“PRA”) and/or the Financial Conduct Authority (“FCA”). The PRA’s primary objectives with regard to insurers are to promote the safety and soundness of insurers and to contribute to the securing of an appropriate degree of protection for current and future policyholders. The FCA has three operational objectives: (i) to secure an appropriate degree of protection for consumers, (ii) to protect and enhance the integrity of the United Kingdom’s financial system, and (iii) to promote effective competition in the interests of consumers in the financial services markets. The PRA and FCA employ a variety of regulatory tools to achieve their objectives, including periodic auditing and reporting requirements, risk assessment reviews, minimum solvency margins and individual capital assessment requirements, dividend restrictions, in certain cases, approval requirements governing the appointment of key officers, approval requirements governing controlling ownership interests and various other requirements.
Our Lloyd’s managing agency is also regulated by Lloyd’s, and the Lloyd’s syndicate business is subject to Lloyd’s supervision. Through Lloyd’s, we are licensed to write business in various countries throughout the world by virtue of Lloyd’s international licenses. In each such country, we are subject to the laws and insurance regulation of that country. Our insurance subsidiary based in Liechtenstein is regulated by the Financial Market Authority of Liechtenstein ("FMA"), which has regulatory tools analogous to those of the U.K. regulators noted above.
Additionally, U.K. and Liechtenstein laws and regulations also impact us as “controllers” of our European-regulated subsidiaries, whereby we are required to notify the appropriate authorities about significant events relating to such regulated subsidiaries’ controllers (i.e. persons or entities which have certain levels of direct or indirect voting power or economic interests in the regulated entities) as well as changes of control, and to submit annual reports regarding their controllers. The PRA/FCA’s Senior Managers and Certification Regime and analogous regulation in Liechtenstein further provide regulatory frameworks for standards of fitness and propriety, conduct and accountability for individuals in positions of responsibility at insurers. In addition, certain employees are individually registered at Lloyd’s.
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Our insurance business throughout the EU and EEA is subject to “Solvency II,” an insurance regulatory regime governing, among other things, capital adequacy and risk management. Following the U.K.’s withdrawal from the EU, or Brexit, our Lloyd’s managing agency (and the U.K. branch of our Liechtenstein subsidiary) are now subject to a separate U.K. prudential regime, which is broadly identical to Solvency II but will diverge from Solvency II in the future. The U.K. has recently adopted legislative reforms that amended various parts of the U.K.’s prudential regime, including the risk margin, matching adjustment requirements and regulatory reporting obligations. The legislative reforms relating to the risk margin took effect from December 31, 2023, and other areas of reform will come into force throughout 2024.
Similarly, the EU’s legislative bodies have undertaken a review of Solvency II. In September 2021, the European Commission published a package of proposed legislative reforms for amending the existing regulatory framework. The legislative bodies reached a provisional agreement on the revised text of Solvency II in December 2023. A finalized set of rules will now be prepared, which EU member states will implement into their domestic legislation.
Solvency II provides for the supervision of group solvency. Under Solvency II, it is possible that the U.S. parent of a European Union subsidiary could be subject to certain Solvency II requirements if the U.S. company is not already subject to regulations deemed “equivalent” to Solvency II. Currently, the U.S. system of insurance regulation relating to group supervision is not deemed “equivalent” to Solvency II by European Union authorities. The PRA will also perform separate, but comparable, supervision of group solvency under the U.K.’s own domestic prudential regime where a U.S. holding company is a parent of a subsidiary U.K. insurer or reinsurer.
The Liechtenstein financial services regulator, the FMA, is the group supervisor for our European-regulated subsidiaries. However, the Covered Agreements prohibit any EU supervisor or the PRA (as applicable) from exercising group-wide supervision at any level above the highest company organized in the country of that supervisor.
We must also comply with the EU General Data Protection Regulation (EU) 2016/879) (“GDPR”), which took effect in May 2018, including EEA member state legislation implementing the GDPR. The regulation’s goal is to impose increased individual rights and protections for all personal data located in or originating from the EU. The Data Protection Act 2018 and the U.K. General Data Protection Regulation, which is the retained EU law version of the GDPR by virtue of the European Union (Withdrawal) Act 2018 and as amended by the Data Protection, Privacy and Electronic Communications (Amendments etc.) (EU Exit) Regulations 2019 (together, “U.K. GDPR”), regulate data protection for all individuals within the U.K. Both the GDPR and the U.K. GDPR are extraterritorial in that they apply to all businesses in the EU and the U.K. respectively and any business outside the EU and the U.K. that offers services, or monitors the behavior of individuals, in the EU and/or U.K., and that processes the personal data of individuals in the EU and/or the U.K. Moreover, there are significant fines associated with non-compliance. In particular, we need to monitor our compliance with all relevant member states’ laws and regulations, including where permitted derogations from the GDPR and the U.K. GDPR are introduced. The introduction of the GDPR and the U.K. GDPR, and any resultant changes in EU member states’ or U.K. national laws and regulations, has increased our compliance obligations and has necessitated the review and implementation of policies and processes relating to our collection and use of data, and has required us to change our business practices regarding these matters.
In addition, we may become subject to or affected by regulatory policies adopted by the IAIS, an international standard setter consisting of supervisors and regulators from more than 200 jurisdictions. The IAIS has been working on several initiatives to consider changes to insurer solvency standards and group supervision of companies in a holding company system in response to the increasing globalization of the insurance sector. In November 2019, the IAIS formally adopted a global framework for the supervision of IAIGs, which is referred to as the Common Framework for the Supervision of Internationally Active Insurance Groups, or “ComFrame.” ComFrame is intended to provide a framework of basic standards for IAIGs and a process for supervisors to cooperate in the supervision of IAIGs. Also in November 2019, the IAIS adopted a risk-based group-wide global insurance capital standard (“ICS”) that will apply to IAIGs and ultimately form a part of ComFrame. The ICS commenced a five-year monitoring period in January 2020 which is being used for confidential reporting and discussion in supervisory colleges to provide feedback to the IAIS on the ICS’s design and performance, but will not trigger any supervisory action. Following this monitoring period, the ICS is expected to be implemented in 2025 as a group-wide prescribed capital requirement for IAIGs and integrated into the rest of ComFrame. The IAIS is also conducting a comparability assessment to determine whether an aggregation method approach to a group capital standard, which forms part of the NAIC’s group capital calculation, produces comparable outcomes to the ICS. As noted above under “U.S. Regulation,” it is unclear how the development of the ICS will interact with existing capital requirements for insurance companies in the United States and the NAIC’s development of the group capital calculation. We have received notice from Delaware, our lead state insurance regulator, that we may be considered an IAIG. In the event that we are deemed to be an IAIG, we would be subject to international oversight coordinated by the Delaware Department of Insurance.
Our international operations are also subject to varying degrees of regulation in Mexico, Australia and Canada and in certain other countries in Europe, South America, and Southeast Asia. Generally, our subsidiaries must satisfy local regulatory
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requirements. While each country imposes licensing, solvency, auditing and financial reporting requirements, the type and extent of the requirements differ substantially. Key areas where country regulations may differ include: (i) the type of financial reports to be filed; (ii) a requirement to use local intermediaries; (iii) the amount of reinsurance permissible; (iv) the scope of any regulation of policy forms and rates; and (v) the type and frequency of regulatory examinations.
Competition 
The property casualty insurance and reinsurance businesses are highly competitive, with many insurance companies of various sizes, as well as other entities offering risk alternatives such as self-insured retentions or captive programs, transacting business in the United States and internationally. We compete directly with a large number of these companies. Competition in our industry is largely measured by the ability to provide insurance and services at a price and on terms that are reasonable and acceptable to the customer. Our strategy in this highly fragmented industry is to seek specialized areas or geographic regions where our businesses can gain a competitive advantage by responding quickly to changing market conditions. Our businesses establish their own pricing practices based upon a Company-wide philosophy to price products with the intent of making an underwriting profit.
Competition for insurance business within the United States comes from other specialty insurers, regional carriers, large national multi-line companies and reinsurers. Our specialty businesses compete with excess and surplus insurers as well as standard carriers. Our regional businesses compete with mutual and other regional stock companies as well as national carriers. Additionally, direct writers of property casualty insurance compete with our regional businesses by writing insurance through their salaried employees, generally at a lower acquisition cost than through independent agents such as those used by the Company. We compete internationally with native insurance operations both large and small, which in some cases are related to government entities, as well as with branches or local subsidiaries of multinational companies.
Competition for reinsurance business, which is especially strong, comes from domestic and foreign reinsurers, which produce their business either on a direct basis or through the broker market. These competitors include Swiss Re, Munich Re, Berkshire Hathaway, Partner Re and others.
In recent years, various institutional investors have increasingly sought to participate in the property and casualty insurance and reinsurance industries. Well-capitalized new entrants to the property and casualty insurance and reinsurance industries, or existing competitors that receive substantial infusions of capital, provide increasing competition, which may adversely impact our business and profitability. Further, an expanded supply of reinsurance capital may lower costs for insurers that rely on reinsurance and, as a consequence, those insurers may be able to price their products more competitively.
Human Capital Resources 
As of January 15, 2024, we employed 8,329 individuals. Of this number, our subsidiaries employed 8,194 individuals and the remaining individuals were employed at the parent company.
We believe that our people are our greatest asset and that our corporate culture is the most important intangible driver of long-term value creation for our Company and the highest priority for pursuing long-term risk-adjusted returns and growth in stockholder value.
Human Capital Management: The Company fosters a performance culture. We are focused on creating a respectful, rewarding, diverse, and inclusive work environment that allows our employees to build meaningful and productive careers. The success of these human capital management objectives is essential to our strategy, as it is our people who drive our success. We invest in their growth as individuals and professionals through training and engagement, as well as in their well-being through robust health and wellness programs and a commitment to diversity.
The Company provides developmental opportunities for our employees through formal and informal programs that focus on enabling employees to build skills and thought leadership in specific facets of our business. Our leadership programs cultivate the talent of our high-potential, strong-performing employees as we strive to deepen, enhance and diversify the Company’s leadership team.
We strive to align employee incentives with the risk and performance frameworks of the Company. The Company’s “pay for performance” philosophy connects individual, business and Company results to employee compensation, providing employees with opportunities to share in the Company’s overall growth and success. The Company offers employees a comprehensive benefits package, including health and wellness, financial, educational and life management benefits. In addition, we support employees in making an impact in their local communities and globally through environmental and social efforts that are meaningful to them.
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Our Board of Directors engages with our senior leadership team, including our senior vice president - human resources, on a periodic basis across a range of human capital management issues, including succession planning and development, compensation, benefits, talent recruiting and retention, engagement, diversity and inclusion, and employee feedback.
Culture: The Board of Directors has recognized Accountability, People Oriented Strategy, Responsible Financial Practices, Risk-Adjusted Returns and Transparency as the elements of corporate culture necessary for the Company to achieve success. Our culture unifies our employees across our decentralized business model, positions us to serve our diverse clients globally and propels the Company’s continuous evolution.
We are committed to fostering a unifying culture and encouraging innovation across our enterprise. Our culture encompasses the beliefs that (i) specialized knowledge and having a customer-centric focus are competitive advantages and (ii) an environment that promotes integrity, embraces the commitment to “always do right,” fosters entrepreneurship and innovation, and values making thoughtful decisions for the long-term benefit of our enterprise. While there is no one “Berkley” way, each of our businesses has its own culture that embodies a shared set of values that define our enterprise. Our structure, with 60 distinct businesses, facilitates the prompt identification of and appropriate action with respect to addressing individual business or cultural issues arising within a business, without affecting the larger enterprise. Furthermore, our businesses are overseen by senior corporate business managers and senior corporate functional managers, including actuarial, underwriting, compliance and finance, providing a governance oversight structure that makes it easier to identify such issues. Because our Board of Directors diligently exercises its risk management oversight through, among other activities, regular interactions with employees beyond corporate senior management, our directors have visibility into and receive timely feedback on cultural issues that may affect our business.
As significant owners of our Company who are required to hold their shares until separation from service, each of our directors and senior executives have a vested interest in cultivating talent and perpetuating a culture that facilitates the execution of our long-term objectives.
Other Information about the Company's Business
We maintain an interest in evaluating the startup of possible new ventures and the acquisition of complementary businesses on an ongoing basis. In addition, our businesses develop new coverages or enter lines of business to meet the needs of insureds.
Seasonal weather variations and other events affect the severity and frequency of losses sustained by the insurance and reinsurance businesses. Although the effect on our business of catastrophes such as tornadoes, hurricanes, hailstorms, wildfires, earthquakes and terrorist acts may be mitigated by reinsurance, they nevertheless can have a significant impact on the results of any one or more reporting periods. 
We have no customer that accounts for 10 percent or more of our consolidated revenues.
Compliance by W. R. Berkley and its subsidiaries with federal, state and local provisions that have been enacted or adopted regulating the discharge of materials into the environment, or otherwise relating to protection of the environment, has not had a material effect upon our capital expenditures, earnings or competitive position.
The Company's internet address is www.berkley.com. The information on our website is not incorporated by reference in this annual report on Form 10-K. The Company's annual report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act and other reports filed by us or with respect to our securities by others are accessible free of charge through this website as soon as reasonably practicable after they have been electronically filed with or furnished to the SEC.


ITEM 1A. RISK FACTORS
Our businesses face significant risks. If any of the events or circumstances described as risks below occur, our businesses, results of operations and/or financial condition could be materially and adversely affected. In addition to those described below, our businesses may also be adversely affected by risks and uncertainties not currently known to us or that we currently consider immaterial.
Risks Relating to Our Industry 
Our results may fluctuate as a result of many factors, including cyclical changes in the insurance and reinsurance industry.
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The results of companies in the property casualty insurance industry historically have been subject to significant fluctuations and uncertainties in demand and pricing, causing cyclical changes in the insurance and reinsurance industry. The demand for insurance is influenced primarily by general economic conditions, while the supply of insurance is often directly related to available capacity or the perceived profitability of the business. At times, we have faced significant competition in our business as a result of existing insurers seeking to gain or maintain market share as well as new entrants and capital providers. Recently, premium rates have increased for most lines of business, while they have decreased in others, most notably workers' compensation and certain professional liability lines of business. The adequacy of premium rates is affected mainly by the severity and frequency of claims, which are influenced by many factors, including natural disasters, regulatory measures and court decisions that define and expand the extent of coverage, and the effects of economic and social inflation on the amount of claims payments due for injuries or losses. In addition, investment rates of return impact rate adequacy. These factors can have a significant impact on ultimate profitability because a property casualty insurance policy is priced before its costs are known as premiums usually are determined long before claims are reported. These factors could produce results that would have a negative impact on our results of operations and financial condition.
We face significant competitive pressures in our businesses, which can pressure premium rates in certain areas and could harm our ability to maintain or increase our profitability and premium volume in some parts of our business. 
We compete with a large number of other companies in our selected lines of business. We compete, and will continue to compete, with major U.S. and non-U.S. insurers and reinsurers, other regional companies, as well as mutual companies, specialty insurance companies, underwriting agencies, diversified financial services companies and insurtech companies. Competitiveness in our businesses is based on many factors, including premium charges, ratings assigned by independent rating agencies, commissions paid to producers, the perceived financial strength of the company, other terms and conditions offered, services provided, ease of doing business, speed of claims payment and reputation and experience in the lines to be written. Periods of insurance industry consolidation may further increase competition in some parts of our business and may cause our insurance subsidiaries to incur greater customer retention and acquisition expenses, affecting the profitability of existing and new business.
Some of our competitors, particularly in the reinsurance business, have greater financial and/or marketing resources than we do. These competitors within the reinsurance market include Swiss Re, Munich Re, Berkshire Hathaway and Partner Re. We expect that perceived financial strength, in particular, will become more important as customers seek high quality reinsurers.
Recently, insurance prices have generally increased for most lines of business, excluding workers' compensation and certain professional liability lines of business. However, loss costs have also increased and the duration and magnitude of the improving pricing environment remains uncertain. Despite higher interest rates, current price levels for certain lines of business may remain below the prices required for us to achieve our long-term return objectives. We expect to continue to face strong competition in our business.
In recent years, various types of investors have increasingly sought to participate in the property and casualty insurance and reinsurance industries. Well-capitalized new entrants to the property and casualty insurance and reinsurance industries, or existing competitors that receive substantial infusions of capital or access to third-party capital, provide increasing competition, which may adversely impact our business and profitability. Further, an expanded supply of capital may lower costs for insurers and, as a consequence, those insurers may be able to price their products more competitively. In addition, technology companies or other third parties have created, and may in the future create, technology-enabled business models, processes, platforms or alternate distribution channels that may adversely impact our competitive position in some parts of our business.
This intense competition could cause the supply and/or demand for insurance or reinsurance to change, which affect our ability to price our products at attractive rates and retain existing business or write new products at adequate rates or on terms and conditions acceptable to us. If we are unable to retain existing business or write new business at adequate rates or on terms and conditions acceptable to us, our results of operations could be materially and adversely affected.
Our actual claims losses may exceed our reserves for claims, which may require us to establish additional reserves. 
Our gross reserves for losses and loss expenses were approximately $18.7 billion as of December 31, 2023. Our loss reserves reflect our best estimates of the cost of settling claims and related expenses with respect to insured events that have occurred. 
Reserves do not represent an exact calculation of liability. Rather, reserves represent an estimate of what management expects the ultimate settlement and claims administration will cost for claims that have occurred, whether known or unknown. The major assumptions about anticipated loss emergence patterns are subject to unanticipated fluctuation. These estimates, which generally involve actuarial projections, are based on management's assessment of facts and circumstances then known, as