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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D. C. 20549

FORM 10-K

(Mark One)

Annual Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934
For the fiscal year ended December 31, 2023

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 001-11294

Unum Group
(Exact name of registrant as specified in its charter)
Delaware
62-1598430
(State or other jurisdiction of incorporation or organization)(I.R.S. Employer Identification No.)
1 Fountain Square
Chattanooga, Tennessee
37402
(Address of principal executive offices)(Zip Code)
(423)294-1011
(Registrant's telephone number, including area code)

Securities registered pursuant to Section 12(b) of the Act:
Title of each classTrading Symbol(s)Name of each exchange on which registered
Common stock, $0.10 par value
UNM
New York Stock Exchange
6.250% Junior Subordinated Notes due 2058
UNMA
New 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 [X] No [ ]

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes [ ] No [X]

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 [X] No [ ]

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes [X] No [ ]




Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, 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.
(Check one):
Large Accelerated Filer
xAccelerated filer
Non-accelerated filer¨ Smaller 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 shares of the registrant's common stock held by non-affiliates (based upon the closing price of these shares on the New York Stock Exchange) as of the last business day of the registrant's most recently completed second fiscal quarter was $9.4 billion. As of February 16, 2024, there were 191,518,006 shares of the registrant's common stock outstanding.



DOCUMENTS INCORPORATED BY REFERENCE

Portions of the information required by Part III of this Form 10-K are incorporated herein by reference from the registrant's definitive proxy statement for its 2024 Annual Meeting of Stockholders which will be filed with the Securities and Exchange Commission pursuant to Regulation 14A under the Securities Exchange Act of 1934, as amended, within 120 days after the end of the registrant's fiscal year ended December 31, 2023.




 TABLE OF CONTENTS
Page



Cautionary Statement Regarding Forward-Looking Statements
The Private Securities Litigation Reform Act of 1995 (the Act) provides a "safe harbor" to encourage companies to provide prospective information, as long as those statements are identified as forward-looking and are accompanied by meaningful cautionary statements identifying important factors that could cause actual results to differ materially from those included in the forward-looking statements. Certain information contained in this Annual Report on Form 10-K (including certain statements in the business description in Item 1, Management's Discussion and Analysis in Item 7, and the consolidated financial statements and related notes in Item 8), or in any other written or oral statements made by us in communications with the financial community or contained in documents filed with the Securities and Exchange Commission (SEC), may be considered forward-looking statements within the meaning of the Act. Forward-looking statements are those not based on historical information, but rather relate to our outlook, future operations, strategies, financial results, or other developments. Forward-looking statements speak only as of the date made. We undertake no obligation to update these statements, even if made available on our website or otherwise. These statements may be made directly in this document or may be made part of this document by reference to other documents filed by us with the SEC, a practice which is known as "incorporation by reference." You can find many of these statements by looking for words such as "will," "may," "should," "could," "believes," "expects," "anticipates," "estimates," "plans," "assumes," "intends," "projects," "goals,” "objectives," or similar expressions in this document or in documents incorporated herein.

These forward-looking statements are subject to numerous assumptions, risks, and uncertainties, many of which are beyond our control. We caution readers that the following factors, in addition to other factors mentioned from time to time, may cause actual results to differ materially from those contemplated by the forward-looking statements:

Fluctuation in insurance reserve liabilities and claim payments due to changes in claim incidence, recovery rates, mortality and morbidity rates, and policy benefit offsets due to, among other factors, the rate of unemployment and consumer confidence, the emergence of new diseases, epidemics, or pandemics, new trends and developments in medical treatments, the effectiveness of our claims operational processes, and changes in governmental programs.
Sustained periods of low interest rates.
Unfavorable economic or business conditions, both domestic and foreign, that may result in decreases in sales, premiums, or persistency, as well as unfavorable claims activity or unfavorable returns on our investment portfolio.
The impact of pandemics and other public health issues on our business, financial position, results of operations, liquidity and capital resources, and overall business operations.
Changes in, or interpretations or enforcement of, laws and regulations.
A cybersecurity attack or other security breach resulting in compromised data or the unauthorized acquisition of confidential data.
The failure of our business recovery and incident management processes to resume our business operations in the event of a natural catastrophe, cybersecurity attack, or other event.
Investment results, including, but not limited to, changes in interest rates, defaults, changes in credit spreads, impairments, and the lack of appropriate investments in the market which can be acquired to match our liabilities.
Increased competition from other insurers and financial services companies due to industry consolidation, new entrants to our markets, or other factors.
Ineffectiveness of our derivatives hedging programs due to changes in forecasted cash flows, the economic environment, counterparty risk, ratings downgrades, capital market volatility, changes in interest rates, and/or regulation.
Changes in our financial strength and credit ratings.
Actual experience in the broad array of our products that deviates from our assumptions used in pricing, underwriting, and reserving.
Our ability to hire and retain qualified employees.
Our ability to develop digital capabilities or execute on our technology systems upgrades or replacements.
Availability of reinsurance in the market and the ability of our reinsurers to meet their obligations to us.
Ability to generate sufficient internal liquidity and/or obtain external financing.
Damage to our reputation due to, among other factors, regulatory investigations, legal proceedings, external events, and/or inadequate or failed internal controls and procedures.
Disruptions to our business or our ability to leverage data caused by the use and reliance on third party vendors, including vendors providing web and cloud based applications.
Recoverability and/or realization of the carrying value of our intangible assets, long-lived assets, and deferred tax assets.
Effectiveness of our risk management program.
Contingencies and the level and results of litigation.
Fluctuation in foreign currency exchange rates.
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Our ability to meet environment, social, and governance standards and expectations of investors, regulators, customers, and other stakeholders.

All subsequent written and oral forward-looking statements attributable to us or any person acting on our behalf are expressly qualified in their entirety by the cautionary statements contained or referred to in this section.
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PART I

ITEM 1. BUSINESS

General

Unum Group, a Delaware general business corporation, and its insurance and non-insurance subsidiaries, which collectively with Unum Group we refer to as the Company, operate in the United States, the United Kingdom, Poland, and, to a limited extent, in certain other countries. The principal operating subsidiaries in the United States are Unum Life Insurance Company of America (Unum America), Provident Life and Accident Insurance Company (Provident), The Paul Revere Life Insurance Company (Paul Revere Life), Colonial Life & Accident Insurance Company, Unum Insurance Company, Starmount Life Insurance Company (Starmount), in the United Kingdom, Unum Limited, and in Poland, Unum Zycie TUiR S.A. (Unum Poland). We are a leading provider of financial protection benefits in the United States and the United Kingdom. Our products include disability, life, accident, critical illness, dental and vision, and other related services. We market our products primarily through the workplace.

We have three principal operating business segments: Unum US, Unum International, and Colonial Life. Our other segments are the Closed Block and Corporate segments. These segments are discussed more fully under "Reporting Segments" included herein in this Item 1.

Business Strategies

The benefits we provide help the working world thrive throughout life's moments and protect people from the financial hardship of illness, injury, or loss of life. As a leading provider of employee benefits, we offer a broad portfolio of products and services through the workplace that provide support when it is needed most.

Specifically, we offer group, individual, voluntary, and dental and vision products as well as provide certain fee-based services. These products and services, which can be sold stand-alone or combined with other coverages, help employers of all sizes attract and retain the talented and capable workforce they need to succeed while protecting the incomes and livelihood of their employees. We believe employer-sponsored benefits are the most effective way to provide workers with access to information and options to protect their financial stability. Working people and their families, particularly those at lower and middle incomes, are perhaps the most vulnerable in today's economy yet are often overlooked by many providers of financial products and services. For many of these workers and families, employer-sponsored benefits are the primary defense against the potentially catastrophic financial impact of death, illness, or injury.
 
We have established a corporate culture consistent with the social value of our products and services. Because we see important links between the obligations we have to all of our stakeholders, we place a strong emphasis on operating with integrity and contributing to positive change in our communities. Accordingly, we are committed not only to meeting the needs of our customers who depend on us, but also to being accountable for our actions through sound and consistent business practices, a strong internal compliance program, a comprehensive risk management strategy, and an engaged employee workforce.
 
We believe our disciplined approach to providing financial protection products at the workplace puts us in a position of strength. The products and services we provide have never been more important to employers, employees, and their families. Our strategy remains centered on growing our core businesses through investing and transforming our operations and technology to anticipate and respond to the changing needs of the marketplace, driving enhanced customer experiences and expanding into new adjacent markets through meaningful partnerships and effective deployment of our capital across our portfolio.

We continue to analyze and employ strategies we believe will help us navigate the current environment and allow us to maintain financial flexibility to support the needs of our businesses while also allowing us to return capital to our shareholders. As we have seen in the current environment, we have substantial leverage to inflation and strong labor markets which generate wage and payroll growth. To the extent that our own costs increase as a result of wage inflation, we have the ability to adjust our prices on new and renewing business to reflect these higher costs.

Long-term, we believe that consistent operating results, combined with the implementation of strategic initiatives and the effective deployment of capital, will allow us to meet our financial objectives.

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Reporting Segments

Our reporting segments are comprised of the following: Unum US, Unum International, Colonial Life, Closed Block, and Corporate. The percentage of consolidated premium income generated by each reporting segment for the year ended December 31, 2023 is as follows:

Unum US65.5 %
Unum International8.2 
Colonial Life17.2 
Closed Block9.1 
Total100.0 %

Financial information is provided in "Management's Discussion and Analysis of Financial Condition and Results of Operations" contained herein in Item 7 and Note 15 of the "Notes to Consolidated Financial Statements" contained herein in Item 8.

Unum US Segment

Our Unum US segment is comprised of group disability, group life and accidental death and dismemberment, and supplemental and voluntary lines of business. The group disability line of business includes long-term and short-term disability, medical stop-loss, and fee-based service products. The supplemental and voluntary line of business includes voluntary benefits, individual disability, and dental and vision products. Unum US products are issued primarily by Unum America, Provident, Starmount, and Unum Insurance Company. These products are marketed through our field sales personnel who work in conjunction with independent brokers and consultants. Our market strategy for Unum US is to effectively deliver an integrated offering of employee benefit products in the group core market segment, which we define for Unum US as employee groups with fewer than 2,000 employees, the group large case market segment, and the supplemental and voluntary market segment.

The percentage of Unum US segment premium income generated by each product line during 2023 is as follows:

Group Disability46.7 %
Group Life and Accidental Death & Dismemberment28.2 
Voluntary Benefits12.9 
Individual Disability8.0 
Dental and Vision4.2 
Total100.0 %

Group Long-term and Short-term Disability

We sell group long-term and short-term disability products to employers for the benefit of employees.

Group long-term disability provides employees with insurance coverage for loss of income in the event of extended work absences due to sickness or injury. We offer services to employers and insureds to encourage and facilitate rehabilitation, retraining, and re-employment. Most policies begin providing benefits following 90 or 180 day waiting periods and continue providing benefits until the employee reaches a certain age, generally between 65 and 70, or recovers from the disability. The benefits are limited to specified maximums as a percentage of income. Also included in our long-term disability product line is our medical stop-loss product, which is designed to protect self-insured employers if their employees' medical claims exceed certain agreed upon thresholds.

Group short-term disability insurance generally provides coverage from loss of income due to injury or sickness for up to 26 weeks and is limited to specified maximums as a percentage of income. Benefits are typically effective after 0 to 30 days for accidents and after 7 to 30 days for sickness.

Our fee-based services include leave management and administrative services only (ASO) business. Leave management services provide administrative services on behalf of employers to ensure the protected leave eligibility and status for employees are in accordance with applicable laws and regulations. ASO products provide administrative services regarding
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claims processing and billing for self-insured customers for which the responsibility for funding claim payments remains with the customer.

Premiums for group long-term and short-term disability are generally based on expected claims of a pool of similar risks plus provisions for administrative expenses, investment income, and profit. In some cases, coverage for large employers will include retrospective experience rating provisions or will be underwritten on an experience-rated basis. Premiums for experience-rated group long-term and short-term disability business are based on the expected experience of the client given its demographics, industry group, and location, adjusted for the credibility of the specific claim experience of the client. Both group long-term and short-term disability are sold primarily on a basis permitting periodic repricing to address the underlying claims experience. Fees for our leave management services and ASO business are generally based on the number of covered employees and an agreed-upon per-employee, per-month rate. Premiums for our medical stop-loss product are generally based on the number of covered employees in self-insured employer groups and their estimated overall health risk plus provisions for administrative expenses, and profit.

We have defined underwriting practices and procedures. If the coverage amount for our disability policies exceeds certain prescribed age and amount limits, we may require a prospective insured to submit evidence of insurability. Our disability policies are typically issued, both at inception and renewal, with rate guarantees. For new group policyholders, the usual rate guarantee is one to three years. For group policies being renewed, the rate guarantee is generally one year, but may be longer. The profitability of the policy depends on the adequacy of the rate during the rate guarantee period. The contracts provide for certain circumstances in which the rate guarantees can be overridden. Our medical stop loss contracts are renewable on an annual basis and rates are not guaranteed beyond one year. There is no requirement for prospective medical stop loss insureds to submit evidence of insurability because coverage levels are determined for the group as a whole.

Profitability of group long-term and short-term disability insurance and our medical stop-loss product is affected by sales, persistency, investment returns, claims experience, and the level of administrative expenses. Morbidity is an important factor in disability claims experience, and many economic and societal factors can affect claim incidence for disability insurance. We routinely make pricing adjustments on our group long-term and short-term disability insurance products, when contractually permitted, which take into account emerging experience and external factors.

Group Life and Accidental Death and Dismemberment

Group life and accidental death and dismemberment products are sold to employers as employee benefit products. Group life consists primarily of renewable term life insurance with the coverages frequently linked to employees' wages and includes a provision for waiver of premium, if disabled. Accidental death and dismemberment consists primarily of an additional benefit amount payable if death or severe injury is attributable to an accident.

Premiums are generally based on expected claims of a pool of similar risks plus provisions for administrative expenses, investment income, and profit. Underwriting practices and rate guarantees are similar to those used for group disability products, and evidence of insurability is required for benefits in excess of a specified limit.

Profitability of group life and accidental death and dismemberment insurance is affected by persistency, investment returns, mortality and other claims experience, and the level of administrative expenses.

Voluntary Benefits

Voluntary benefits products are primarily sold to groups of employees through payroll deduction at the workplace and include accident, disability, life, hospital indemnity, cancer, and critical illness. Products are issued on both a group and individual basis.

Premiums are generally based on assumptions for morbidity, mortality, persistency, administrative expenses, investment income, and profit. We develop our assumptions based on our own experience and published industry tables. Our underwriters evaluate the medical condition of prospective policyholders prior to the issuance of a policy on a simplified basis. Underwriting requirements may be waived for cases that meet certain criteria, including participation levels. Individual voluntary benefits products other than life insurance are offered on a guaranteed renewable basis which allows us to reprice in-force policies, subject to regulatory approval. Group voluntary benefits products are offered primarily on an optionally renewable basis which allows us to reprice or terminate in-force policies.

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Profitability of voluntary benefits products is affected by the level of employee participation, persistency, investment returns, mortality and other claims experience, and the level of administrative expenses.

Individual Disability

Individual disability products are offered primarily to multi-life employer groups to supplement their group disability plans and may be funded by the employer, but the policy is owned by the employee and is portable. Individual disability insurance provides the insured with a portion of earned income lost as a result of sickness or injury. The benefits, including the underlying group disability coverage, typically range from 30 percent to 75 percent of the insured's monthly earned income. We provide various options with respect to length of benefit periods, product features, and waiting periods before benefit payments begin, which permit tailoring of the multi-life plan to a specific employer's needs. We also market individual disability policies which include payments for the transfer of business ownership between partners and payments for business overhead expenses, also on a multi-life basis. Individual disability products do not provide for the accumulation of cash values.

Premium rates for individual disability products vary by age, product features, industry, region, and occupation based on assumptions concerning morbidity, mortality, persistency, administrative expenses, investment income, and profit. We develop our assumptions based on our own experience. Our underwriting rules, issue limits, and plan designs reflect risk and the financial circumstances of prospective insureds. Individuals in multi-life groups may be subject to limited medical underwriting. The majority of our individual disability policies are written on a noncancelable basis. Under a noncancelable policy, as long as the insured continues to pay the fixed annual premium for the policy's duration, we cannot cancel the policy or change the premium.

Profitability of individual disability insurance is affected by persistency, investment returns, claims experience, and the level of administrative expenses.

Dental and Vision

Group dental and vision products are sold to employers as employee benefit products. Our group dental products include a variety of insured and self-insured dental care plans including preferred provider organizations and scheduled reimbursement plans. Our group vision products provide coverage that includes a range of both in-network and out-of-network benefits for routine vision services offered either in conjunction with our dental product offerings or as stand-alone coverage.

Premiums for small case group dental and vision products are generally based on expected claims of a pool of similar risks plus a provision for administrative expenses, investment income, and profit. Premiums for large employer groups are underwritten on an experience-rated basis.

Profitability of our dental and vision products is affected by persistency, claims experience, the level of administrative expenses, and to a lesser extent, investment returns.

Unum International Segment

Our Unum International segment includes our operations in the United Kingdom and Poland. Unum UK's business includes insurance for group long-term disability, group life, and supplemental lines of business which include dental, individual disability, and critical illness products. Unum Poland's business primarily includes insurance for individual and group life with accident and health riders. Unum International's products are sold primarily through field sales personnel and independent brokers and consultants. The market strategy for the segment is to offer benefits to employers and employees through the workplace, with a focus on the expansion of the number of employers and employees covered in our Unum UK business, and the growth of the existing Unum Poland business through the incorporation of our benefits and distribution expertise.

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The percentage of Unum International segment premium income generated by each product line during 2023 is as follows:
Unum UK
Group Long-term Disability48.0 %
Group Life20.5 
Supplemental17.2 
Unum Poland14.3 
Total100.0 %

Unum UK Group Long-term Disability

Group long-term disability products are sold to employers for the benefit of employees. Group long-term disability provides employees with insurance coverage for loss of income in the event of extended work absences due to sickness or injury. Services are offered to employers and insureds to encourage and facilitate rehabilitation, retraining, and re-employment. Most policies begin providing benefits following 90 or 180 day waiting periods and continue providing benefits until the employee reaches a certain age or reaches the end of the limited period specified in the policy terms. The benefits are limited to specified maximums as a percentage of income.

Premiums for group long-term disability are generally based on expected claims of a pool of similar risks plus provisions for administrative expenses, investment income, and profit. Some cases carry experience rating provisions. Premiums for experience-rated group long-term disability business are based on the expected experience of the client given its demographics, industry group, and location, adjusted for the credibility of the specific claim experience of the client. Policies are sold primarily on a basis permitting periodic repricing to address the underlying claims experience.

We have defined underwriting practices and procedures.  If the coverage amount exceeds certain prescribed age and amount limits, we may require a prospective insured to submit evidence of insurability. Policies are typically issued, both at inception and renewal, with rate guarantees. The usual rate guarantee is two years but may vary depending on circumstances.  The profitability of the policy is dependent upon the adequacy of the rate during the rate guarantee period. The contracts provide for certain circumstances in which the rate guarantees can be overridden.

Profitability of group long-term disability insurance is affected by sales, persistency, investment returns, claims experience, and the level of administrative expenses. Morbidity is an important factor in disability claims experience. We routinely make pricing adjustments on our group insurance products, when contractually permitted, which take into account emerging experience and external factors.

Unum UK Group Life

Group life products are sold to employers as employee benefit products. Group life consists of two types of products, a renewable term life insurance product and a group dependent life product. The renewable term life product provides a lump sum benefit to the beneficiary upon the death of an employee. The group dependent life product, which we discontinued offering to new customers in 2012, provides an annuity to the beneficiary upon the death of an employee. Both coverages are frequently linked to employees' wages. Premiums for group life are generally based on expected claims of a pool of similar risks plus provisions for administrative expenses, investment income, and profit. Underwriting and rate guarantees are similar to those utilized for Unum UK group long-term disability products.

Profitability of group life is affected by sales, persistency, investment returns, mortality and other claims experience, and the level of administrative expenses.    

Unum UK Supplemental

Supplemental products are sold to employers and groups of employees and include group critical illness and group dental products. Group critical illness products provide a lump-sum benefit on the occurrence of a covered critical illness event. Group dental products generally provide fixed benefits based on specified treatments or a portion of the cost of the treatment. Beginning in 2022, supplemental products are no longer actively marketed to individual customers.

Premiums for group critical illness products are generally based on expected claims of a pool of similar risks plus provisions for administrative expenses, investment income, and profit. Underwriting and rate guarantees are similar to those utilized for
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Unum UK group long-term disability products. Premiums for group dental products are generally based on expected claims of a pool of similar risks plus provisions for administrative expenses and profit, with minor pricing variation based on the number of covered employees in the group. Profitability of our supplemental products is affected by persistency, investment returns, claims experience, and the level of administrative expenses.

Unum Poland

Unum Poland products, which include both individual and group life products, provide renewable term and whole life insurance with accident and health riders. Premiums are based on expected claims of a pool of similar risks plus provisions for administrative expenses, investment income, and profit. Profitability of our Unum Poland products is affected by persistency, investment returns, mortality and other claims experience, and the level of administrative expenses.

Colonial Life Segment

Our Colonial Life segment includes accident, sickness, and disability products, life products, and cancer and critical illness products. Products are issued primarily by Colonial Life & Accident Insurance Company and marketed to employees, on both a group and an individual basis, at the workplace through an independent contractor agent sales force and brokers. Our market strategy for Colonial Life is to effectively deliver a broad set of voluntary products and services in the public sector market and in the commercial market, with a particular focus on the core commercial market segment, which we define for Colonial Life as accounts with fewer than 1,000 employees.

Our underwriters evaluate the medical condition of prospective policyholders prior to the issuance of a policy on a simplified basis. Underwriting requirements may be waived for cases that meet certain criteria, including participation levels.

The percentage of Colonial Life segment premium income generated by each product line during 2023 is as follows:

Accident, Sickness, and Disability54.8 %
Life24.7 
Cancer and Critical Illness20.5 
Total100.0 %

Accident, Sickness, and Disability

The accident, sickness, and disability product line consists of short-term disability plans, accident-only plans providing benefits for injuries on a specified loss basis, and our dental and vision products. It also includes accident and health plans which cover events such as hospital admissions, confinement, and surgeries.

Premiums are generally based on assumptions for morbidity, mortality, persistency, administrative expenses, investment income, and profit. We develop our assumptions based on our own experience and published industry tables. Premiums are primarily individual guaranteed renewable which allows us to change premiums on a state by state basis. A small percentage of the policies are written on a group basis which are offered primarily on an optionally renewable basis which allows us to reprice or terminate in-force policies. Premiums for our dental and vision products are guaranteed renewable with standard industry rates that vary by age and region.
Profitability is affected by the level of employee participation, persistency, investment returns, claims experience, and the level of administrative expenses.

Life

Life products are primarily comprised of universal life, whole life, and term life policies. We discontinued offering universal life policies in 2019.

Premiums are generally based on assumptions for mortality, persistency, administrative expenses, investment income, and profit. We develop our assumptions based on our own experience and published industry tables. Premiums for the individual whole life and term life products are guaranteed for the life of the contract. Premiums for the individual universal life products are flexible and may vary at the individual policyholder level. For the group term life products, we retain the right to change premiums at the account level based on the experience of the account.
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Profitability is affected by the level of employee participation, persistency, investment returns, mortality and other claims experience, and the level of administrative expenses.

Cancer and Critical Illness

Cancer policies provide various benefits for the treatment of cancer including hospitalization, surgery, radiation, and chemotherapy. Critical illness policies provide a lump-sum benefit and/or fixed payments on the occurrence of a covered critical illness event.

Premiums are generally based on assumptions for morbidity, mortality, persistency, administrative expenses, investment income, and profit. We develop our assumptions based on our own experience and published industry tables. Premiums are primarily individual guaranteed renewable wherein we have the ability to change premiums on a state by state basis. A small percentage of the policies are written on a group basis and are offered primarily on an optionally renewable basis which allows us to reprice or terminate in-force policies.

Profitability of these products is affected by the level of employee participation, persistency, investment returns, mortality and other claims experience, and the level of administrative expenses.

Closed Block Segment

Our Closed Block segment consists of group and individual long-term care and other insurance products no longer actively marketed. Closed Block segment premium income for 2023 was comprised of approximately 76 percent group and individual long-term care and 24 percent other insurance products.

Group and Individual Long-term Care

We discontinued offering individual long-term care in 2009 and group long-term care in 2012. Group long-term care was previously offered to employers for the benefit of employees. Individual long-term care was previously marketed on a single-life customer basis.

Long-term care insurance pays a benefit upon the loss of two or more activities of daily living and the insured's requirement of standby assistance or cognitive impairment. Payment is generally made on an indemnity basis, regardless of expenses incurred, up to a lifetime maximum. Benefits begin after a waiting period, usually 90 days or less, and are generally paid for a period of three years, six years, or lifetime.

Our long-term care insurance was sold on a guaranteed renewable basis which allows us to reprice in-force policies, subject to regulatory approval. Premium rates for long-term care vary by age and are based on assumptions concerning morbidity, mortality, persistency, administrative expenses, investment income, and profit. Premium rate increases continue to be implemented where needed and where approved by state regulators. We develop our assumptions based on our own claims and persistency experience and published industry tables.

Profitability is affected by premium rate increases, persistency, investment returns, mortality and other claims experience, and the level of administrative expenses.

Other

Other insurance products not actively marketed include individual disability, group pension, individual life and corporate-owned life insurance, reinsurance pools and management operations, and other miscellaneous product lines. The majority of these products have been reinsured, with approximately 85 percent of reserves at December 31, 2023 ceded to other insurance companies.

In December 2020, we entered into the first phase of a reinsurance transaction to reinsure the majority of our Closed Block individual disability products to a third party. In March 2021, we completed the second phase of the reinsurance transaction to reinsure a portion of the remaining Closed Block individual disability business that was not ceded in December 2020. For further discussion on this reinsurance transaction, refer to "Reinsurance" herein in this Item 1, "Executive Summary" and "Segment Results" contained herein in Item 7, and Note 14 of the "Notes to Consolidated Financial Statements" contained herein in Item 8.
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Corporate Segment

Our Corporate segment includes investment income on corporate assets not specifically allocated to a line of business, interest expense on corporate debt, and certain other corporate income and expenses not allocated to a line of business.

Reinsurance

In the normal course of business, we assume reinsurance from and cede reinsurance to other insurance companies. In a reinsurance transaction, a reinsurer agrees to indemnify another insurer for part or all of its liability under a policy or policies it has issued for an agreed upon premium or fee. We undertake reinsurance transactions for both risk management and capital management. If the assuming reinsurer in a reinsurance agreement is unable to meet its obligations, we remain contingently liable. In the event that reinsurers do not meet their obligations under the terms of the reinsurance agreement, reinsurance recoverable balances could become uncollectible. We evaluate the financial condition of reinsurers to whom we cede business and monitor concentration of credit risk to minimize our exposure. We may also require assets to be held in trust, letters of credit, or other acceptable collateral to support reinsurance recoverable balances. The collectability of our reinsurance recoverable is primarily a function of the solvency of the individual reinsurers. Although we have controls to minimize our exposure, the insolvency of a reinsurer or the inability or unwillingness of a reinsurer to comply with the terms of a reinsurance contract could have a material adverse effect on our results of operations.

In general, the maximum amount of life insurance risk retained by our U.S. insurance subsidiaries under group or individual life or group or individual accidental death and dismemberment policies during 2023 was $1 million per covered life per policy. The retention amount remains at $1 million for 2024. For Unum Limited life insurance risk, during 2023 we had reinsurance agreements which provided 75 percent quota share coverage up to £500 thousand per covered life for group dependent life benefits and 25 percent quota share coverage for group lump sum benefits, as well as 100 percent coverage per covered life above that amount. For Unum Limited, during 2024, we have reinsurance agreements which provide 20 percent quota share coverage for group lump sum benefits up to £500 thousand per covered life as well as 100 percent coverage per covered life above that amount. For Unum Limited in both 2023 and 2024, we have reinsured 100 percent of benefits in excess of £2 million for both group dependents and lump sum benefits.

In December 2020, we completed the first phase of a reinsurance transaction, pursuant to which Provident, Paul Revere Life, and Unum America, collectively referred to as "the ceding companies", each entered into separate reinsurance agreements with Commonwealth Annuity and Life Insurance Company (Commonwealth), a subsidiary of Global Atlantic Financial Group, to reinsure on a coinsurance basis effective as of July 1, 2020 approximately 75 percent of the Closed Block individual disability business, primarily direct business written by the ceding companies. In March 2021, we completed the second phase of the reinsurance transaction, pursuant to which the ceding companies and Commonwealth amended and restated their respective reinsurance agreements to reinsure on a coinsurance and modified coinsurance basis, effective as of January 1, 2021, a substantial portion of the remaining Closed Block individual disability business that was not ceded in December 2020, primarily business previously assumed by the ceding companies. Commonwealth established and will maintain collateralized trust accounts for the benefit of the ceding companies to secure its obligations under the reinsurance agreements.

Also in December 2020, Provident Life and Casualty Insurance Company (PLC), also a wholly-owned domestic insurance subsidiary of Unum Group, entered into an agreement with Commonwealth whereby PLC will provide a 12-year volatility cover to Commonwealth for the active life cohort (ALR cohort). On March 31, 2021, PLC and Commonwealth amended and restated this agreement to incorporate the ALR cohort related to the additional business that was reinsured between the ceding companies and Commonwealth as part of the second phase of the transaction. At the end of the 12-year coverage period, Commonwealth will retain the risk for the remaining incidence and claims risk on the ALR cohort of the ceded business. Under this volatility cover, annual settlements will be made equal to the difference between the actual and estimated cash flows and reserve changes during the year. Upon expiration of the 12-year period, a terminal settlement will be made based on the final reserves for the ALR cohort. Due to the nature of the volatility cover, the ALR cohort will be accounted for under the deposit method on a U.S. generally accepted accounting principles (GAAP) basis.

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We have global catastrophic reinsurance coverage which covers all Unum Group insurance companies and includes four layers of coverage to limit our exposure under life, accidental death and dismemberment, long-term care, and disability policies in regard to a catastrophic event. Each layer provides coverage for catastrophic events, including most acts of war and any type of terrorism, up to $1 million of coverage per person per policy for each U.S. and Poland line of covered business, and up to £2 million of coverage for each U.K. covered line of business. We have the following coverage for 2024, after a $150 million deductible:
Layer
Coverage Layer (in millions)
Percent Coverage
Coverage (in millions)
First$100.0 50.0 %$50.0 
Second100.0 55.0 55.0 
Third150.0 55.0 82.5 
Fourth300.0 55.0 165.0 
Total Catastrophic Coverage$352.5 

In addition to the global catastrophic reinsurance coverage noted above, Unum Limited has additional catastrophic coverage via an arms-length, intercompany reinsurance agreement with Unum America, under similar terms as the global catastrophic treaties. Unum Limited has the following additional coverage for 2024, after a £80 million deductible:

Layer
Coverage Layer (in millions)
Percent Coverage
Coverage (in millions)
First£40.0 80.0 %£32.0 
Second30.0 40.0 12.0 
Total Catastrophic Coverage£