BERKLEY W R CORP (Form: 10-K, Received: 02/20/2020 16:22:56)

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2016-12-31 xbrli:pure xbrli:shares iso4217:USD iso4217:USD xbrli:shares wrb:claim wrb:hour wrb:segment

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, 2019



☐	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 Road	Greenwich,	CT	06830
(Address of principal executive offices)			(Zip Code)

Registrant’s telephone number, including area code: (203) 629-3000

Securities registered pursuant to Section 12(b) of the Act:



Title of each class	Trading Symbol(s)	Name of each exchange on which registered

Common Stock, par value $.20 per share	WRB	New York Stock Exchange
5.625% Subordinated Debentures due 2053	WRB PRB	New York Stock Exchange
5.90% Subordinated Debentures due 2056	WRB PRC	New York Stock Exchange
5.75% Subordinated Debentures due 2056	WRB PRD	New York Stock Exchange
5.70% Subordinated Debentures due 2058	WRB PRE	New York Stock Exchange
5.10% Subordinated Debentures due 2059	WRB PRF	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 ☒ 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 filer	☒	Accelerated 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 is a shell company (as defined in Rule 12b-2 of the Act). Yes ☐ No ☒

The aggregate market value of the voting and non-voting common stock held by non-affiliates (computed by reference to the price at which the common stock was last sold) as of the last business day of the registrant’s most recently completed second fiscal quarter was $9,617,776,032.

Number of shares of common stock, $.20 par value, outstanding as of February 18, 2020: 183,421,709

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, 2019, are incorporated herein by reference in Part III.



			Page
SAFE HARBOR STATEMENT
	PART I
ITEM	1.	BUSINESS	1
ITEM	1A.	RISK FACTORS	19
ITEM	1B.	UNRESOLVED STAFF COMMENTS	28
ITEM	2.	PROPERTIES	28
ITEM	3.	LEGAL PROCEEDINGS	28
ITEM	4.	MINE SAFETY DISCLOSURES	29

	PART II
ITEM	5.	MARKET FOR REGISTRANT’S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES	30
ITEM	6.	SELECTED FINANCIAL DATA	32
ITEM	7.	MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS	33
ITEM	7A.	QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK	57
ITEM	8.	FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA	58
ITEM	9.	CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURE	109
ITEM	9A.	CONTROLS AND PROCEDURES	109
ITEM	9B.	OTHER INFORMATION	111

	PART III
ITEM	10.	DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE	112
ITEM	11.	EXECUTIVE COMPENSATION	112
ITEM	12.	SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND RELATED STOCKHOLDER MATTERS	112
ITEM	13.	CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTOR INDEPENDENCE	112
ITEM	14.	PRINCIPAL ACCOUNTING FEES AND SERVICES	112

	PART IV
ITEM	15.	EXHIBITS, FINANCIAL STATEMENT SCHEDULES	113
ITEM	16.	FORM 10-K SUMMARY	117
EX-4.1		DESCRIPTION OF REGISTRANT’S SECURITIES REGISTERED PURSUANT TO SECTION 12 OF THE SECURITIES EXCHANGE ACT OF 1934
EX-21		LIST OF COMPANIES AND SUBSIDIARIES
EX-23		CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
EX-31.1		CERTIFICATION OF THE CHIEF EXECUTIVE OFFICER PURSUANT TO RULE 13a-14(a) /15d-14(a)
EX-31.2		CERTIFICATION OF THE CHIEF FINANCIAL OFFICER PURSUANT TO RULE 13a-14(a) /15d-14(a)
EX-32.1		CERTIFICATION OF THE CHIEF EXECUTIVE OFFICER AND CHIEF FINANCIAL OFFICER PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002
EX-101		INSTANCE DOCUMENT
EX-101		SCHEMA DOCUMENT
EX-101		CALCULATION LINKBASE DOCUMENT
EX-101		LABELS LINKBASE DOCUMENT
EX-101		PRESENTATION LINKBASE DOCUMENT
EX-101		DEFINITION LINKBASE DOCUMENT

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 2020 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 alternative 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 impact of climate change, which may increase the frequency and 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;


•	foreign currency and political risks (including those associated with the United Kingdom's withdrawal from the European Union, or "Brexit") 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 2015 ("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;


•	potential difficulties with technology and/or cyber security issues;


•	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”).

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 2020 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.

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 - 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 the United Kingdom, Continental Europe, South America, Canada, Mexico, Scandinavia, Asia and Australia.


•	Reinsurance & Monoline Excess - reinsurance business on a facultative and treaty basis, primarily in the United States, the United Kingdom, Continental Europe, Australia, the Asia-Pacific region and South Africa, as well as operations that solely retain risk on an excess basis.

Our two reporting segments are each composed of individual operating units that serve a market defined by geography, products, services or industry served. Each of our operating units 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 units 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 52 operating units, 45 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 operating segments for each of the past five years were as follows:



	Year Ended December 31,
(In thousands)	2019			2018			2017			2016			2015
Net premiums written:
Insurance	$	6,086,009		$	5,791,905		$	5,555,515		$	5,597,147		$	5,414,261
Reinsurance & Monoline Excess	777,490			641,322			704,993			826,766			775,254
Total	$	6,863,499		$	6,433,227		$	6,260,508		$	6,423,913		$	6,189,515

Percentage of net premiums written:
Insurance	88.7		%	90.0		%	88.7		%	87.1		%	87.5		%
Reinsurance & Monoline Excess	11.3			10.0			11.3			12.9			12.5
Total	100.0		%	100.0		%	100.0		%	100.0		%	100.0		%

Thirty 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: “The Financial Strength Rating opinion addresses the relative ability of an insurer to meet its ongoing insurance obligations. The ratings are not assigned to specific insurance policies or contracts and do 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-four insurance company subsidiaries rated by Standard & Poor's (“S&P”) have financial strength ratings of A+ (the seventh 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 sixth 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 A+ (the seventh highest rating out of twenty-seven possible ratings).

The following sections describe our reporting segments and their operating units in greater detail. These operating units underwrite on behalf of one or more affiliated insurance companies within the group. The operating units are identified by us 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 operating units. W. R. Berkley Corporation is a Delaware corporation formed in 1970.

Insurance

Our U.S.-based operating units predominantly underwrite commercial insurance business primarily throughout the United States, although many units offer coverage globally, focusing on the following general areas:

Excess & Surplus Lines: A number of our operating units 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 operating units include premises operations, commercial automobile, property, products liability, general liability and professional liability lines. Products are generally distributed through wholesale agents and brokers.

Industry Specialty: Certain other operating units 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 these unique exposures, 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 operating unit 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 operating units 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 units 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 operating units offer standard insurance products and services focused on meeting the specific needs of a geographically differentiated customer base. Key clients of these units are small-to-midsized businesses. These regionally focused operating units 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 operating units, we write business in more than 60 countries worldwide, with branches or offices in 29 locations outside the United States, including the United Kingdom, Continental Europe, South America, Canada, Mexico, Scandinavia, Asia and Australia. 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 operating units also provide a wide variety of fee-based services, including claims, administrative and consulting services.

Operating units 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 and Vermont. In addition to its general offerings, Acadia has specialized expertise in insuring regional industries such as construction, lumber, fishing 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.

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, liquor liability and some property and inland marine coverage. It serves a limited distribution channel consisting of select Berkley member company agents.

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 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 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 FinSecure serves the insurance needs of companies in the financial services industry. It offers a comprehensive range of property, casualty, professional liability, and specialty lines insurance products. Its Berkley crime division provides crime and fidelity related insurance products for commercial organizations, financial institutions and governmental entities.

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 Global Product Recall Management provides worldwide insurance protection and technical assistance to help clients with the prevention, management and indemnification of product recall and contamination events.

Berkley Healthcare underwrites customized, comprehensive insurance solutions for the full spectrum of healthcare providers. Through Berkley Med, 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, public schools, sports and recreational organizations, and special events. Its product offerings include traditional primary coverages and risk purchasing groups, as well as alternative market solutions for clients who wish to retain a larger share of their risks.

Berkley Industrial specializes in mono-line workers’ compensation coverage for mining and mining related and high hazard industries in select states.

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.

Berkley Insurance Australia underwrites general insurance business in Australia, including professional indemnity insurance for companies of all sizes.

Berkley Latinoamérica is a leading provider of property, casualty, automobile, 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 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 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 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 Net Underwriters also manages Berkley's assigned risk servicing carrier operations.

Berkley North Pacific provides local underwriting, claims and risk management services for businesses in the Northwest. It operates with a select group of agents in Idaho, Montana, Oregon, Utah and Washington to sell and service property and casualty policies for larger middle-market standard businesses and specialty lines, such as construction, restaurants and manufacturing.

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, liability and collectibles. Berkley One targets high net worth individuals and families with sophisticated risk management 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, tax opinion insurance and contingency liability insurance.

Berkley Program Specialists is a program management company 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, or programs, allowing for efficient processes, effective oversight of existing programs and sound implementation of new 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, automobile 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.

Berkley Select specializes in underwriting professional liability insurance on a surplus lines basis for law firms and accounting firms through a limited number of brokers. It also offers executive and professional liability products, including directors and officers liability, errors and omissions, and employment practices liability, to small to middle market privately held and not for profit customers on both an admitted and surplus lines basis.

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 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 18 field locations.

Berkley Technology Underwriters provides a broad range of first and third-party insurance programs for technology exposures and technology industries on both a local and global basis.

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.

Continental Western Group is a Midwest regional property and casualty insurance operation based in Des Moines, Iowa, 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. It includes Berkley Prime Transportation, which leverages analytics and technology to provide quality products and responsive service to the commercial transportation industry.

Intrepid Direct offers business coverages to franchise restaurants, auto service and repair garages, junk hauler franchisors and gym and fitness franchises on a direct basis.

Key Risk provides workers' compensation insurance to middle market accounts in several niches that appreciate expertise and exceptional service. The unit operates two business units; one focused on middle market accounts located primarily in the mid-Atlantic and southeastern United States and one focused on national temporary staffing and United States Longshoreman & Harbor Act (USL&H) specialty programs. Its products are distributed by a select group of independent retail agents and wholesale brokers located through 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 in California. It serves over 18,000 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 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.

Verus Underwriting Managers offers general liability, professional liability and property coverages for small to mid-sized commercial risks in the excess and surplus lines insurance market through a select group of appointed wholesale brokers and agents.

W R B Europe is comprised of specialist operating units offering a focused range of insurance products to markets in Continental Europe and Nordic countries.

W / R / B Underwriting provides a broad range of leading insurance products to the Lloyd's marketplace, with a concentration in specialist classes of business including property, professional indemnity, crisis management, and asset protection.

The following table sets forth the percentage of gross premiums written by each Insurance operating unit:



	Year Ended December 31,
	2019	2018	2017	2016	2015
Acadia Insurance	5.9%	6.7%	7.0%	6.9%	6.9%
Admiral Insurance	5.9	5.8	5.8	5.7	5.0
Berkley Accident and Health	5.7	5.7	4.9	4.5	3.8
Berkley Agribusiness	1.1	1.2	1.2	1.1	0.9
Berkley Alliance Managers	3.0	2.6	2.0	1.5	0.7
Berkley Aspire	0.4	0.3	0.3	0.3	0.4
Berkley Canada	1.0	1.0	0.9	0.8	0.6
Berkley Custom Insurance	3.1	2.7	2.6	2.7	2.9
Berkley Cyber Risk Solutions	0.3	0.2	0.1	—	—
Berkley Entertainment	2.7	2.6	2.2	2.1	2.0
Berkley Environmental	4.9	5.1	4.7	4.2	3.8
Berkley FinSecure	0.9	0.9	1.0	0.9	1.0
Berkley Fire & Marine	0.7	0.6	0.5	0.4	0.3
Berkley Global Product Recall Management	0.5	0.5	0.3	0.2	—
Berkley Healthcare	1.6	1.2	1.1	1.0	1.0
Berkley Human Services	0.8	0.8	0.7	0.7	0.6
Berkley Industrial	0.9	0.9	0.8	0.7	0.8
Berkley Insurance Asia	0.6	0.4	0.2	—	—
Berkley Insurance Australia	1.2	1.2	1.0	1.1	0.8
Berkley Latinoamérica	3.6	4.2	4.9	4.2	4.8
Berkley Life Sciences	0.7	0.8	0.8	0.8	0.8
Berkley Luxury Group	1.3	1.4	1.4	1.3	1.3
Berkley Mid-Atlantic Group	1.2	1.2	1.1	1.2	1.8
Berkley Net Underwriters	3.0	5.0	6.8	8.2	4.1
Berkley North Pacific	0.8	1.2	1.5	1.6	1.7
Berkley Offshore Underwriting Managers	1.2	1.1	1.1	1.1	1.4
Berkley Oil & Gas	4.1	3.6	2.7	2.8	3.3
Berkley One	0.3	0.2	—	—	—
Berkley Professional Liability	2.9	1.9	1.6	1.6	1.8
Berkley Program Specialists	1.1	1.1	1.3	1.2	1.2
Berkley Public Entity	0.4	0.4	0.5	0.5	0.5
Berkley Risk	0.3	0.2	0.3	0.2	4.1
Berkley Select	2.8	3.2	3.5	4.0	4.1
Berkley Southeast	2.0	2.0	1.9	2.0	2.4
Berkley Surety	1.2	1.3	1.2	1.2	1.3
Berkley Technology Underwriters	0.7	0.7	0.7	0.6	0.5
Carolina Casualty	0.7	0.5	0.4	0.6	1.3
Continental Western Group	2.6	3.5	3.9	4.1	4.1
Gemini Transportation	2.9	2.3	2.1	1.9	1.1
Intrepid Direct	0.5	0.3	0.1	—	—
Key Risk	2.7	2.9	2.8	2.7	2.9
Nautilus Insurance Group	4.8	5.0	5.2	5.1	4.8
Preferred Employers Insurance	2.4	2.5	2.9	2.6	2.5
Union Standard	2.1	2.7	2.8	2.7	2.7
Vela Insurance Services	2.8	2.6	3.1	4.0	3.4
Verus Underwriting Managers	0.8	0.9	0.9	0.9	0.9
WRB Europe	1.4	1.9	1.8	1.8	1.9
W/R/B Underwriting	4.5	3.5	3.2	4.1	5.6
Other	3.0	1.5	2.2	2.2	2.5
Total	100.0%	100.0%	100.0%	100.0%	100.0%

The following table sets forth percentages of gross premiums written, by line, by our Insurance operations:



	Year Ended December 31,
	2019	2018	2017	2016	2015
Other liability	33.9%	32.4%	31.4%	31.4%	30.1%
Short-tail lines (1)	23.5	23.5	23.5	23.6	24.8
Workers' compensation	17.8	20.6	22.7	23.4	23.8
Professional liability	13.3	12.0	11.2	11.0	9.7
Commercial auto	11.5	11.5	11.2	10.6	11.6
Total	100.0%	100.0%	100.0%	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 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.

Operating units 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, Melbourne, Sydney, Beijing, Hong Kong, 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"), and liquor liability insurance to help enhance their clients' product offerings, along with underwriting, claims, and actuarial consultation.

Berkley Re UK writes international property casualty treaty 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.

The following table sets forth the percentages of gross premiums written by each Reinsurance & Monoline Excess operating unit:



	Year Ended December 31,
	2019		2018		2017		2016		2015
Berkley Re America	34.2	%	31.7	%	41.0	%	53.1	%	49.4	%
Berkley Re Asia Pacific	12.0		11.2		9.8		8.3		12.6
Berkley Re Solutions	12.2		10.7		10.0		7.6		6.6
Berkley Re UK	15.3		16.8		12.3		9.0		8.3
Lloyd's Syndicate 2791 Participation	4.8		5.1		4.3		3.7		4.2
Midwest Employers Casualty	21.5		24.5		22.0		17.8		18.9
Other	—		—		0.6		0.5		—
Total	100.0	%	100.0	%	100.0	%	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,
	2019		2018		2017		2016		2015
Casualty	55.7	%	53.0	%	52.2	%	47.9	%	52.6	%
Property	22.8	%	22.5	%	25.8	%	34.3	%	28.5	%
Monoline Excess	21.5	%	24.5	%	22.0	%	17.8	%	18.9	%
Total	100.0	%	100.0	%	100.0	%	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)	2019			2018			2017		2016			2015
Insurance
Revenue	$	6,397,074		$	6,208,290		$	6,003,130	$	5,935,268		$	5,664,654
Income before income taxes	814,862			717,154			623,746		671,347			658,748
Reinsurance & Monoline Excess
Revenue	877,551			848,966			922,478		990,065			957,125
Income before income taxes	189,188			201,001			117,131		226,069			212,697
Other (1)
Revenue	627,571			634,395			759,156		728,851			584,678
(Loss) income before income taxes	(151,130		)	(106,061		)	31,893		(978		)	(139,415		)
Total
Revenue	$	7,902,196		$	7,691,651		$	7,684,764	$	7,654,184		$	7,206,457
Income before income taxes	$	852,920		$	812,094		$	772,770	$	896,438		$	732,030

_______________________________________


(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.

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,
	2019		2018		2017		2016		2015
Insurance
Loss ratio	62.4	%	62.5	%	62.5	%	61.9	%	60.9	%
Expense ratio	31.1		32.6		33.0		32.5		32.6
Combined ratio	93.5	%	95.1	%	95.5	%	94.4	%	93.5	%
Reinsurance & Monoline Excess
Loss ratio	61.5	%	61.0	%	70.0	%	55.7	%	57.7	%
Expense ratio	35.0		35.8		35.7		37.8		37.1
Combined ratio	96.5	%	96.8	%	105.7	%	93.5	%	94.8	%
Total
Loss ratio	62.3	%	62.4	%	63.4	%	61.1	%	60.5	%
Expense ratio	31.5		32.9		33.3		33.2		33.2
Combined ratio	93.8	%	95.3	%	96.7	%	94.3	%	93.7	%

Investments

Investment results, before income taxes, were as follows:



	Year Ended December 31,
(In thousands)	2019			2018			2017			2016			2015
Average investments, at cost (1)	$	19,145,567		$	18,392,297		$	17,530,590		$	16,730,964		$	15,970,931
Net investment income (1)	$	645,614		$	674,235		$	575,788		$	564,163		$	512,645
Percent earned on average investments (1)	3.4		%	3.7		%	3.3		%	3.4		%	3.2		%
Net realized and unrealized gains on investments (2)	$	120,703		$	154,488		$	335,858		$	267,005		$	92,324
Change in unrealized investment gains (losses) (3)	$	261,970		$	(302,737	)	$	(69,425	)	$	371,715		$	(192,186	)

_______________________________________


(1)	Includes investments, cash and cash equivalents, trading accounts receivable from brokers and clearing organizations, trading account securities sold but not yet purchased and unsettled purchases.

(2)

Represents realized gains on investments not classified as trading account securities prior to 2018. The inclusion of change in unrealized gains on equity securities within net income commenced January 1, 2018 due to our adoption of ASU 2016-01. The twelve months ended December 31, 2019 includes net realized gains on investment sales of $36 million and increased by a change in unrealized gains on equity securities of $85 million. The twelve months ended December 31, 2018 includes net realized gains on investment sales of $480 million reduced by a change in unrealized gains on equity securities of $320 million as well as $6 million in other-than-temporary impairments.

(3)

Represents the change in unrealized investment gains (losses) for available for sale securities recognized in stockholders' equity. Effective January 1, 2018, the Company adopted accounting guidance that requires all equity investments with readily determinable fair values (subject to certain exceptions) to be measured at fair value with changes in the fair value recognized in net income. As a result of this guidance, the Company recorded a cumulative effect adjustment of $291 million that increased retained earnings and decreased accumulated other comprehensive income ("AOCI"), resulting in no net impact to total 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,
	2019		2018		2017		2016		2015
Barclays U.S. Aggregate Bond Index	3.2	%	3.0	%	3.0	%	3.0	%	3.0	%
S&P 500^® Index	2.3		2.0		2.4		2.4		2.1

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.



	Year Ended December 31,
	2019		2018		2017		2016		2015
1 year or less	6.5	%	6.9	%	5.0	%	7.9	%	5.8	%
Over 1 year through 5 years	35.9		34.3		37.2		39.6		33.6
Over 5 years through 10 years	24.7		22.3		24.8		24.6		30.5
Over 10 years	21.4		24.7		23.3		18.8		20.3
Mortgage-backed securities	11.5		11.8		9.7		9.1		9.8
Total	100.0	%	100.0	%	100.0	%	100.0	%	100.0	%

At December 31, 2019, the fixed maturity portfolio had an effective duration of 2.8 years, including cash and cash equivalents.

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.

The Company discounts its liabilities for certain workers’ compensation reserves. The amount of workers’ compensation reserves that were discounted was $1,731 million and $1,793 million at December 31, 2019 and 2018, respectively. The aggregate net discount for those reserves, after reflecting the effects of ceded reinsurance, was $530 million and $563 million at December 31, 2019 and 2018, respectively. At December 31, 2019, discount rates by year ranged from 2.0% to 6.5%, with a weighted average discount rate of 3.7%.

Substantially all discounted workers’ compensation reserves (97% of total discounted reserves at December 31, 2019) 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, 2019), 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 $24 million at December 31, 2019 and $28 million at December 31, 2018. 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)	2019			2018			2017
Net reserves at beginning of year	$	10,248,883		$	10,056,914		$	9,590,265
Net provision for losses and loss expenses:
Claims occurring during the current year (1)	4,057,989			3,926,489			3,963,543
Increase (decrease) in estimates for claims occurring in prior years (2)	34,079			6,831			(5,165		)
Loss reserve discount amortization	39,048			41,382			43,970
Total	4,131,116			3,974,702			4,002,348
Net payments for claims:
Current year	985,599			964,808			1,027,405
Prior years	2,673,803			2,700,077			2,562,550
Total	3,659,402			3,664,885			3,589,955
Foreign currency translation	(22,599		)	(117,848		)	54,256
Net reserves at end of year	10,697,998			10,248,883			10,056,914
Ceded reserves at end of year	1,885,251			1,717,565			1,613,494
Gross reserves at end of year	$	12,583,249		$	11,966,448		$	11,670,408

Net change in premiums and losses occurring in prior years:
(Increase) decrease in estimates for claims occurring in prior years (2)	$	(34,079	)	$	(6,831	)	$	5,165
Retrospective premium adjustments for claims occurring in prior years (3)	53,511			45,638			32,162
Net favorable premium and reserve development on prior years	$	19,432		$	38,807		$	37,327

____________________________________


(1)	Claims occurring during the current year are net of loss reserve discounts of $20 million, $24 million and $22 million in 2019, 2018 and 2017, 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 increased by $19 million in 2019, and decreased by $4 million in 2018 and $32 million in 2017, respectively.


(3)	For certain retrospectively rated insurance polices 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, 2019 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	$	10,292,373
Reserves for non-U.S. companies	447,526
Loss reserve discounting (1)	(41,901		)
Ceded reserves	1,885,251
Gross reserves reported in the consolidated GAAP financial statements	$	12,583,249

_________________________


(1)	For statutory purposes, the Company discounts its workers’ compensation reinsurance reserves at 3.3% 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 subject to varying degrees of regulation and supervision in the jurisdictions in which they do business.

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 excess and surplus and reinsurance subsidiaries, must generally file all rates with the insurance department of each state in which they operate. Our excess and surplus and reinsurance subsidiaries generally operate free of rate and form regulation.

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 state insurance commissioner, including information concerning our capital structure, ownership, financial condition and general business operations.

In addition, we must annually submit to our lead state regulator 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.

Approximately half the states have also 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, as discussed below under “- International Regulation.” This framework includes a risk-based, group-wide global insurance capital standard (“ICS”), which will undergo a five-year monitoring period starting in January 2020. In the U.S., the National Association of Insurance Commissioners (“NAIC”) is developing 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. The NAIC expects to adopt the group capital calculation tool in 2020. It is unclear how the development of group capital measures will interact with existing capital requirements for insurance companies in the United States and with international capital standards. It is possible that we may be required to hold additional capital as a result of these developments.

Nearly 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”). The ORSA 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 ORSA, we are required to:


•	regularly, no less than annually, conduct an ORSA 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 a confidential high-level ORSA Summary Report annually to the Commissioner of Insurance of the State of Delaware (our lead state commissioner).

Cybersecurity Regulations. New York’s cybersecurity regulation for financial services institutions that are authorized by the New York State Department of Financial Services ("Part 500"), including our insurance subsidiaries licensed in New York, became effective on March 1, 2017. The regulation requires these entities to establish and maintain a cybersecurity program designed to protect consumers’ private data and the confidentiality, integrity and availability of the licensee’s information systems. On October 24, 2017, the NAIC adopted the Insurance Data Security Model Law (the “Cybersecurity Model Law”), which establishes standards for data security, the investigation of cybersecurity events involving unauthorized access to, or the misuse of, certain nonpublic information, and reporting to insurance commissioners. The Cybersecurity Model Law imposes significant new regulatory burdens intended to protect the confidentiality, integrity and availability of information systems. Its implementation will be based on adoption by state legislatures. To date, the Cybersecurity Model Law has only been adopted in a few states, including one of our domiciliary states. Importantly, a drafting note in the Cybersecurity Model Law states that a licensee’s compliance with the New York cybersecurity regulation is intended to constitute compliance with the Cybersecurity Model Law.

Certain states are developing or have developed regulations related to privacy and data security. For example, in 2018 California enacted the California Consumer Privacy Act (“CCPA”), which broadly regulates the sale of California residents’ personal information and grants California residents certain rights to, among other things, access and delete data about them in certain circumstances. CCPA became effective on January 1, 2020, and compliance with the CCPA may increase the cost of providing our services in California. Other states have considered - and may adopt - similar proposals. We cannot predict the impact, if any, that any proposed or future cybersecurity regulations will have on our business, financial condition or results of operations.

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 any RBC action level as of December 31, 2019.

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 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, which many states have adopted, limits assessments to an insurer to 2% of its subject premium and permits recoupment of assessments through rate setting. Likewise, several states (or underwriting 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 arrangement 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 2015 (“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 commercial 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 81% of an insurer's covered losses in excess of the insurer's applicable deductible as of January 1, 2020. This amount will decrease to 80% on a pro-rata basis over a five-year period that began in 2017. The insurer's deductible is based on 20% of earned premium for the prior year for covered lines of commercial property and casualty insurance. Based on our 2019 earned premiums, our aggregate deductible under TRIPRA during 2020 will be approximately $993 million. The federal program will not pay losses for certified acts unless such losses exceed $200 million industry-wide for calendar year 2020 and any calendar year thereafter. 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 the 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.

Federal Regulation. Although the federal government and its regulatory agencies generally do not directly regulate the business of insurance, federal initiatives could have an impact on our business in a variety of ways. The Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010 (the “Dodd-Frank Act”) effected sweeping changes to financial services regulation in the United States. The Dodd-Frank Act created two new federal government bodies, the Federal Insurance Office (the “FIO”) and the Financial Stability Oversight Council (the “FSOC”), which may impact the regulation of insurance. Although the FIO has preemption authority over state insurance laws that conflict with certain international agreements, it does not have general supervisory or regulatory authority over the business of insurance. The FIO 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. In May 2018, the Economic Growth, Regulatory Relief and Consumer Protection Act (“Economic Growth Act”) was signed into law. Among other things, the Economic Growth Act addresses the roles played by federal regulators at international insurance standard-setting forums. 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 (a “Covered Agreement”). In September 2017, the U.S. and the European Union ("EU") signed the Covered Agreement.

The Covered Agreement addresses three areas of prudential supervision: reinsurance, group supervision and the exchange of information between the U.S. and EU. Each party is working on its internal requirements and procedures (such as amending

or promulgating appropriate statutes and regulations) in order for the Covered Agreement to become effective. Under the Covered Agreement, reinsurance collateral requirements will no longer apply to qualifying EU reinsurers that sell reinsurance to the U.S. market, and U.S. reinsurers operating in the EU market will no longer be subject to “local presence” requirements. The Covered Agreement establishes group supervision practices that apply only to U.S. and EU insurance groups operating in both territories. For instance, the Covered Agreement states that, provided the U.S. has adopted group supervision including worldwide group governance, solvency, capital and reporting, U.S.-headquartered insurance groups with operations in the EU will be supervised at the worldwide level only by U.S. insurance regulators precluding EU insurance supervisors from exercising solvency and capital requirements over the worldwide operations of U.S.-headquartered insurers.

U.S. states have five years from the date of signature to remove reinsurance collateral requirements for EU reinsurers that meet certain standards (such as minimum capital and solvency ratios and claims payment standards), while EU member states have two years to revise their “local presence” laws. Under the Dodd-Frank Act, the FIO has preemption authority over state insurance laws that conflict with the Covered Agreement. In late 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., which will extend the benefits of a Covered Agreement to the U.K. after Brexit.

Additionally, in June 2019, the NAIC adopted amendments to its Credit for Reinsurance Model Law in order to satisfy the substantive and timing requirements of the Covered Agreement and to pave the way for U.S. states to similarly amend their credit for reinsurance laws and avoid potential federal pre-emption of these laws. The NAIC has also taken steps to make its amended Credit for Reinsurance Model Law an accreditation standard for all states. The newly amended Credit for Reinsurance Model Law also extends the zero reinsurance collateral provisions in the Covered Agreement to 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 the NAIC has identified as “reciprocal jurisdictions” pursuant to the NAIC Qualified Jurisdiction Process. 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 FIO also can recommend to the FSOC that it designate an insurer as an entity posing risks to the United States' financial stability in the event of the insurer's material financial distress or failure, i.e., a "systemically important financial institution" or a "non-bank SIFI." An insurer so designated by FSOC will be subject to Federal Reserve supervision and heightened prudential standards. There are currently no such non-bank SIFIs designated by FSOC. In November 2017, the U.S. Department of Treasury issued a report recommending certain changes to FSOC’s process for designating non-bank SIFIs in order to make the designation process more rigorous, clear and transparent. On December 4, 2019, FSOC approved final guidance related to a revised process for designating non-bank SIFIs, which substantially changes FSOC’s previous procedures by adopting an activities-based approach and moving away from the entities-based approach. The final guidance became effective on January 29, 2020.

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 impacts of the Dodd-Frank Act, its implementing regulations and potential amendments to the Dodd-Frank Act on the U.S. insurance industry are 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 systemically important non-bank financial companies.

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, while 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. Certain of our subsidiaries are authorized by the PRA to effect and carry out contracts of insurance (which includes reinsurance) in the U.K. and are regulated by both the PRA and the FCA for prudential and conduct of business matters respectively.

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, 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.

An insurance company with authorization to write insurance business in the U.K. may currently provide cross-border services in the other member states of the European Economic Area (“EEA”), a group including member states of the EU and Norway, Liechtenstein and Iceland. These rights may be restricted or modified depending on the United Kingdom’s withdrawal from the EU. See below “Risks Relating To Our Business-The United Kingdom leaving the EU could adversely affect our business” for more information.

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 which became effective on January 1, 2016. Lloyd’s applies a capital adequacy test to all Lloyd’s syndicates, including our syndicate, that is based on Solvency II principles. 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. However, we have received a waiver from the PRA, subject to conditions, with respect to the PRA's supervision of our group, which waives the requirement on us to maintain a group solvency capital requirement as calculated under Solvency II rules. The Covered Agreement also prohibits any EU supervisor 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 (“GDPR”), which took effect in May 2018. The regulation’s goal is to impose increased individual rights and protections for all personal data located in or originating from the EU. GDPR is extraterritorial in that it applies to all businesses in the EU and any business outside the EU that process EU personal data of individuals in the EU. Moreover, there are significant fines associated with non-compliance. In particular, we will need to monitor our compliance with all relevant member states' laws and regulations, including where permitted derogations from the GDPR are introduced. The introduction of the GDPR, and any resultant changes in EU member states’ 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 be 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 internationally active insurance groups (“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 will undergo a five-year monitoring period starting in January 2020 during which time it will be used for confidential reporting and discussion in supervisory colleges to provide feedback to the IAIS on the ICS’s design and performance, but it will not trigger any supervisory action. Following the 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. 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 GCC.

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 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 operating units can gain a competitive advantage by responding quickly to changing market conditions. Our operating units 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 operating units compete with excess and surplus insurers as well as standard carriers. Other regional units compete with mutual and other regional stock companies as well as national carriers. Additionally, direct writers of property casualty insurance compete with our regional units 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, Transatlantic Reinsurance, 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.

Employees

As of January 31, 2020, we employed 7,493 individuals. Of this number, our subsidiaries employed 7,356 persons and the remaining persons were employed at the parent company.

Other Information about the Company's Business

We maintain an interest in the acquisition and startup of complementary businesses and continue to evaluate possible acquisitions and new ventures on an ongoing basis. In addition, our operating units 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 operating units. 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.

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. In recent years, we have faced significant competition in our business, as a result of new entrants and capital providers, as well as existing insurers seeking to gain or maintain market share. Recently, premium rates have increased at an accelerating pace for most lines of business, while they have decreased in others, most notably workers' compensation. 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 or social inflation on the amount of compensation due for injuries or losses. In addition, investment rates of return have impacted rate adequacy, with interest rates remaining at or near historic lows. 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 have pressured premium rates in certain areas and could harm our ability to maintain or increase our profitability and premium volume.

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 (including ease of doing business over the internet), speed of claims payment and reputation and experience in the lines to be written. In recent years, the insurance industry has undergone consolidation, which may further increase competition.

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, Transatlantic Reinsurance, and Partner Re. We expect that perceived financial strength, in particular, will become more important as customers seek high quality reinsurers.

Over the past several years, increased supply has led to significant competition in our business. Our E&S operating units have also encountered competition from admitted companies seeking to increase market share. More recently, insurance prices have generally increased for most lines of business, excluding workers' compensation. However, loss costs have also increased and the duration and magnitude of the improving pricing environment remains uncertain. With the low level of interest rates available, 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 these and our other lines of 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 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. 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.

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 $12.6 billion as of December 31, 2019. 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 well as estimates of future trends in claims severity and frequency, inflation, judicial theories of liability, reinsurance coverage, legislative changes and other factors, including the actions of third parties, which are beyond our control.

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 and settlement is reached. In periods with increased economic volatility, it becomes more difficult to accurately predict claim costs. It is especially difficult to estimate the impact of inflation on loss reserves given the current economic environment and related government actions. Both inflation overall and medical cost inflation, which has historically been greater than inflation overall, can have an adverse impact.

Reserve estimates are continually refined in an ongoing process as experience develops and further claims are reported and settled. Adjustments to reserves are reflected in the results of the periods in which such estimates are changed. Because setting reserves is inherently uncertain, we cannot assure that our current reserves will prove adequate in light of subsequent events. Should we need to increase our reserves, our pre-tax income for the reporting period would decrease by a corresponding amount.

We discount our reserves for excess and assumed workers' compensation business because of the long period of time over which losses are paid. Discounting is intended to appropriately match losses and loss expenses to income earned on investment securities supporting liabilities. The expected loss and loss expense payout pattern subject to discounting is derived from our loss payout experience. Changes in the loss and loss expense payout pattern are recorded in the period they are determined. If the actual loss payout pattern is shorter than anticipated, the discount will be reduced and pre-tax income will decrease by a corresponding amount.

The effects of emerging claim and coverage issues on our business are uncertain.

As industry practices and economic, legal, judicial, social and other environmental conditions change, unexpected and unintended issues related to claim and coverage may emerge. These issues may adversely affect our business by either extending coverage beyond our underwriting intent or by increasing the number or size of claims. Examples of emerging claims and coverage issues include, but are not limited to:


•	judicial expansion of policy coverage and a greater propensity to grant claimants more favorable amounts and the impact of new theories of liability;


•	plaintiffs targeting property and casualty insurers, including us, in purported class action litigation relating to claims-handling and other practices;


•	social inflation trends, including higher and more frequent claims, more favorable judgments and legislated increases;


•	medical developments that link health issues to particular causes, resulting in liability claims;


•	claims relating to unanticipated consequences of current or new technologies, including cyber security related risks;


•	claims relating to potentially changing climate conditions; and


•	increased claims due to third party funding of litigation.

In some instances, these emerging issues may not become apparent for some time after we have issued the affected insurance policies. As a result, the full extent of liability under our insurance policies may not be known until many years after the policies are issued.

In addition, the potential passage of new legislation designed to expand the right to sue, to remove limitations on recovery, to extend the statutes of limitations or otherwise to repeal or weaken tort reforms could have an adverse impact on our business.

The effects of these and other unforeseen emerging claim and coverage issues are difficult to predict and could harm our business and materially and adversely affect our results of operations.

As a property casualty insurer, we face losses from natural and man-made catastrophes.

Property casualty insurers are subject to claims arising out of catastrophes that may have a significant effect on their results of operations, liquidity and financial condition. Catastrophe losses have had a significant impact on our results. For example, catastrophe losses net of reinsurance recoveries were $90 million in 2019, $105 million in 2018, and $184 million in 2017. Similarly, man-made catastrophes can also have a material impact on our financial results.

Catastrophes can be caused by various events, including hurricanes, windstorms, earthquakes, tsunamis, hailstorms, explosions, severe winter weather and fires, as well as terrorist and other man-made activities, including drilling, mining and other industrial accidents, cyber events or terrorist activities. The incidence and severity of catastrophes are inherently unpredictable. The extent of losses from a catastrophe is a function of both the total amount of insured exposure in the area affected by the event and the severity of the event. Some catastrophes are restricted to small geographic areas; however, hurricanes, earthquakes, tsunamis and other disasters may produce significant damage in large, heavily populated areas. Catastrophes can cause losses in a variety of our property and casualty lines, and most of our past catastrophe-related claims have resulted from severe storms. Seasonal weather variations or the impact of climate change may affect the severity and frequency of our losses. Insurance companies are not permitted to reserve for a catastrophe until it has occurred. It is therefore possible that a catastrophic event or multiple catastrophic events could produce significant losses and have a material adverse effect on our results of operations and financial condition.

Changing climate conditions may increase the frequency and severity of catastrophic events and thereby adversely affect our financial condition and results.

Over the past several years, changing weather patterns and climatic conditions, such as global warming, appear to have contributed to the unpredictability, frequency and severity of natural disasters and created additional uncertainty as to future trends and exposures. There is a growing scientific consensus that global warming and other climate change are increasing the frequency and severity of catastrophic weather events, such as hurricanes, tornadoes, windstorms, floods and other natural disasters. Such changes make it more difficult for us to predict and model catastrophic events, reducing our ability to accurately price our exposure to such events and mitigate our risks. Any increase in the frequency or severity of natural disasters may adversely affect our financial condition and results.

We, as a primary insurer, may have significant exposure for terrorist acts.

To the extent an act of terrorism, whether a domestic or foreign act, is certified by the Secretary of Treasury, we may be covered under the Terrorism Risk Insurance Program Reauthorization Act of 2015 (“TRIPRA”), for up to 81% of our covered losses as of January 1, 2020 for certain property/casualty lines of insurance. However, any such coverage would be subject to a mandatory deductible based on 20% of earned premium for the prior year for the covered lines of commercial property and casualty insurance. Based on our 2019 earned premiums, our aggregate deductible under TRIPRA during 2020 is approximately $993 million. In addition, the coverage provided under TRIPRA does not apply to reinsurance that we write.

We are subject to extensive governmental regulation, which increases our costs and could restrict the conduct of our business.

We are subject to extensive governmental regulation and supervision in both the United States and foreign jurisdictions. Most insurance regulations are designed to protect the interests of policyholders rather than stockholders and other investors. This system of regulation, generally administered in the United States by a department of insurance in each state in which we do business, relates to, among other things:


•	standards of solvency, including risk-based capital measurements;


•	restrictions on the nature, quality and concentration of investments;


•	requirements pertaining to certain methods of accounting;


•	evaluating enterprise risk to an insurer;


•	rate and form regulation pertaining to certain of our insurance businesses;


•	potential assessments for the provision of funds necessary for the settlement of covered claims under certain policies provided by impaired, insolvent or failed insurance companies; and


•	involvement in the payment or adjudication of catastrophe or other claims beyond the terms of the policies.

State insurance departments conduct periodic examinations of the affairs of insurance companies and require the filing of annual and other reports relating to the financial condition of insurance companies, holding company issues and other matters. Our Insurance business internationally is also generally subject to a similar regulatory scheme in each of the jurisdictions where we conduct operations outside the United States.

Federal financial services modernization legislation and legislative and regulatory initiatives taken or which may be taken in response to conditions in the financial markets, global insurance supervision and other factors may lead to additional federal regulation of the insurance industry in the coming years.

The Dodd-Frank Act effected sweeping changes to financial services regulation in the United States. The Dodd-Frank Act established the Financial Stability Oversight Council (“FSOC”), which is authorized to recommend that certain systemically significant non-bank financial companies, including insurance companies, be regulated by the Board of Governors of the Federal Reserve. The Dodd-Frank Act also established a Federal Insurance Office (“FIO”) which is authorized to study, monitor and report to Congress on the U.S. insurance industry and the significance of global reinsurance to the U.S. insurance market. The FIO also can recommend to the FSOC that it designate an insurer as an entity posing risks to the United States financial stability in the event of the insurer's material financial distress or failure. The potential impact of the Dodd-Frank Act, as amended by the Economic Growth Act, on the U.S. insurance business is not clear. Our business could be affected by changes, whether as a result of the Dodd-Frank Act or otherwise, to the U.S. system of insurance regulation or our designation or the designation of insurers or reinsurers with which we do business as systemically significant non-bank financial companies.

Although state regulation is the primary form of regulation of insurance and reinsurance in the United States, in addition to the changes brought about by the Dodd-Frank Act, Congress has considered various proposals relating to the creation of an optional federal charter and repeal of the insurance company antitrust exemption from the McCarran-Ferguson Act. We may be subject to potentially increased federal oversight as a financial institution. In addition, the current administration and the volatile political environment may increase the chance of other federal legislative and regulatory changes that could affect us in ways we cannot predict.

With respect to international measures, Solvency II, the EU regime concerning the capital adequacy, risk management and regulatory reporting for insurers and reinsurers may affect our insurance businesses. Implementation of Solvency II in EU member states occurred on January 1, 2016, and as the Solvency II regime evolves over time, we may be required to utilize a significant amount of resources to ensure compliance. In addition, despite the waiver of the Solvency II group capital requirements we received, Solvency II may have the effect of increasing the capital requirements of our EU domiciled insurers. Additionally, our capital requirements and compliance requirements may be adversely affected if the EU Commission does not deem the insurance regulatory regimes of the jurisdictions outside the EU in which we have insurance or reinsurance companies domiciled to be "equivalent" to Solvency II. If our compliance with Solvency II or any other regulatory regime is challenged, we may be subject to monetary or other penalties. In addition, in order to ensure compliance with applicable regulatory requirements or as a result of any investigation, including remediation efforts, we could be required to incur significant expenses and undertake additional work, which in turn may divert resources from our business.

We may be unable to maintain all required licenses and approvals and our business may not fully comply with the wide variety of applicable laws and regulations or the relevant authority's interpretation of the laws and regulations. Also, some regulatory authorities have relatively broad discretion to grant, renew or revoke licenses and approvals. If we do not have the requisite licenses and approvals or do not comply with applicable regulatory requirements, the insurance regulatory authorities could preclude or temporarily suspend us from carrying on some or all of our activities or monetarily penalize us. Also, changes in the level of regulation of the insurance industry, whether federal, state or foreign, or changes in laws or regulations themselves or interpretations by regulatory authorities, may further restrict the conduct of our business.

Risks Relating to Our Business

Our international operations expose us to investment, political and economic risks, including foreign currency and credit risk.

Our expanding international operations in the United Kingdom, Continental Europe, South America, Canada, Mexico, Scandinavia, the Asia-Pacific region, South Africa and Australia expose us to increased investment, political and economic risks, including foreign currency and credit risk. Changes in the value of the U.S. dollar relative to other currencies could have an adverse effect on our results of operations and financial condition.

Our investments in non-U.S.-denominated assets are subject to fluctuations in non-U.S. securities and currency markets, and those markets can be volatile. Non-U.S. currency fluctuations also affect the value of any dividends paid by our non-U.S. subsidiaries to their parent companies in the U.S.

The United Kingdom leaving the EU could adversely affect our business.

The 2016 U.K. referendum on its membership in the EU resulted in a majority of U.K. voters voting in favor of the U.K. leaving the EU (“Brexit”). In accordance with the Withdrawal Agreement implementing Brexit, the U.K. formally left the EU on January 31, 2020. The Withdrawal Agreement provides for a transitional period ending on December 31, 2020, during which time the U.K. will continue to enjoy the same rights and obligations as it had as a member state, though without participating in the EU institutions. During the transitional period, the U.K. and the EU are expected to negotiate a long-term agreement covering, among other things, the terms of trade between them, which will be based on the principles set out in the accompanying Political Declaration. However, EU officials and others have expressed skepticism that such a trade deal can be agreed in the time frame allowed. The U.K. government has stated that it will not seek to extend the transitional period. There is, therefore, a risk that at the end of 2020 no trade deal (or only a minimal trade deal) will have been completed, with the result that a “hard” Brexit occurs on December 31, 2020.

Depending on the terms of the long-term trade deal with the EU and/or whether or not a “hard” Brexit occurs on December 31, 2020, the U.K. could lose access to the single EU market and to free trade deals with several countries that already have agreements with the EU.

Such barriers to trade could affect the attractiveness of the U.K. and impact our U.K. business. We also face risks associated with the potential uncertainty and consequences related to Brexit, including with respect to volatility in financial markets, exchange rates and interest rates. These uncertainties could increase the volatility of, or reduce, our investment results in particular periods or over time. Brexit could adversely affect European or worldwide political, regulatory, economic or market conditions and could contribute to instability in political institutions and regulatory agencies. Brexit could also lead to legal uncertainty and differing laws and regulations between the U.K. and the EU. Any of these potential effects, and others we cannot anticipate, could adversely affect our results of operations or financial condition.

We may be unable to attract and retain key personnel and qualified employees.

We depend on our ability to attract and retain key personnel, including our President and CEO, Executive Chairman, senior executive officers, presidents of our operating units, experienced underwriters and other skilled employees who are knowledgeable about our business. If the quality of our underwriting team and other personnel decreases, we may be unable to maintain our current competitive position in the specialized markets in which we operate, and be unable to expand our operations into new products and markets.

We cannot guarantee that our reinsurers will pay in a timely fashion, if at all, and, as a result, we could experience losses.

We purchase reinsurance by transferring part of the risk that we have assumed, known as ceding, to a reinsurance company in exchange for part of the premium we receive in connection with the risk. Although reinsurance makes the reinsurer contractually liable to us to the extent the risk is transferred or ceded to the reinsurer, it does not relieve us, the reinsured, of our liability to our policyholders. Our reinsurers may not pay the reinsurance recoverables that they owe to us or they may not pay such recoverables on a timely basis. Accordingly, we bear credit risk with respect to our reinsurers, and if our reinsurers fail to pay us, our financial results would be adversely affected. Underwriting results and investment returns of some of our reinsurers may affect their future ability to pay claims. As of December 31, 2019, the amount due from our reinsurers was approximately $2,134 million, including amounts due from state funds and industry pools where it was intended that we would bear no risk. Certain of these amounts are secured by letters of credit or by funds held in trust on our behalf.

We are subject to credit risk relating to our policyholders, independent agents and brokers.

In addition to exposure to credit risk related to our reinsurance recoverables and investment portfolio, we are exposed to credit risk in several other areas of our business, including credit risk relating to policyholders, independent agents and brokers. For example our policyholders, independent agents or brokers may not pay a part of or the full amount of premiums owed to us or our brokers or other third party claim administrators may not deliver amounts owed on claims under our insurance and reinsurance contracts for which we have provided funds.

As credit risk is generally a function of the economy, we face a greater credit risk in an economic downturn. While we attempt to manage credit risks through underwriting guidelines, collateral requirements and other oversight mechanisms, our efforts may not be successful. For example, to reduce such credit risk, we require certain third parties to post collateral for some or all of their obligations to us. In cases where we receive pledged securities and the applicable counterparty is unable to honor

its obligations, we may be exposed to credit risk on the securities pledged and/or the risk that our access to that collateral may be stayed as a result of bankruptcy. In cases where we receive letters of credit from banks as collateral and one of our counterparties is unable to honor its obligations, we are exposed to the credit risk of the banks that issued the letters of credit.

We are rated by A.M. Best, Standard & Poor's, Moody's, and Fitch, and a decline in these ratings could affect our standing in the insurance industry and cause our sales and earnings to decrease.

Ratings have become an increasingly important factor in establishing the competitive position of insurance companies. Certain of our insurance company subsidiaries are rated by A.M. Best, Standard & Poor's, Moody's and Fitch. Our ratings are subject to periodic review, and we cannot assure you that we will be able to retain our current or any future ratings.

If our ratings are reduced from their current levels by A.M. Best, Standard & Poor's, Moody's or Fitch, our competitive position in the insurance industry could suffer and it would be more difficult for us to market our products. A ratings downgrade could also adversely limit our access to capital markets, which may increase the cost of debt. A significant downgrade could result in a substantial loss of business as policyholders move to other companies with higher financial strength ratings.

If market conditions cause reinsurance to be more costly or unavailable, we may be required to bear increased risks or reduce the level of our underwriting commitments.

As part of our overall risk and capacity management strategy, we purchase reinsurance for certain amounts of risk underwritten by our insurance company subsidiaries, especially catastrophe risks and those risks with relatively high policy limits. We also purchase reinsurance on risks underwritten by others which we reinsure. Market conditions beyond our control determine the availability and cost of the reinsurance protection we seek to purchase, which may affect the level of our business and profitability. Our reinsurance contracts are generally subject to annual renewal, and we may be unable to maintain our current reinsurance contracts or to obtain other reinsurance contracts in adequate amounts and at favorable rates. In addition, we may be unable to obtain reinsurance on terms acceptable to us relating to certain lines of business that we intend to begin writing. If we are unable to renew our expiring contracts or to obtain new reinsurance contracts, either our net exposures would increase or, if we are unwilling to bear an increase in net exposures, we would have to reduce the level of our underwriting commitments, especially catastrophe exposed risks.

Depending on conditions in the financial markets and the general economy, we may be unable to raise debt or equity capital if needed.

If conditions in the financial markets and the general economy are unfavorable, which may result from disruptions, uncertainty or volatility in the capital and credit markets, we may be unable to access debt or equity capital on acceptable terms if needed, which could have a negative impact on our ability to invest in our insurance company subsidiaries and/or to take advantage of opportunities to expand our business, such as possible acquisitions and the creation of new ventures, and inhibit our ability to refinance our existing indebtedness if we desire to do so, on terms acceptable to us.

We may not find suitable acquisition candidates or new insurance ventures and even if we do, we may not successfully integrate any such acquired companies or successfully invest in such ventures.

As part of our present strategy, we continue to evaluate possible acquisition transactions and the start-up of complementary businesses on an ongoing basis, and at any given time we may be engaged in discussions with respect to possible acquisitions and new ventures. We cannot assure you that we will be able to identify suitable acquisition targets or insurance ventures, that such transactions will be financed and completed on acceptable terms or that our future acquisitions or start-up ventures will be successful. The process of integrating any companies we do acquire or investing in new ventures may have a material adverse effect on our results of operations and financial condition.

If we experience difficulties with our information technology, telecommunications or other computer systems, our ability to conduct our business could be negatively or severely impacted.

Our business is highly dependent upon our employees' ability to perform necessary business functions in an efficient and uninterrupted fashion. A shut-down of, or inability to access, one or more of our facilities, a power outage or a failure of one or more of our information technology, telecommunications or other computer systems could significantly impair our employees' ability to perform such functions on a timely basis. In the event of a disaster such as a natural catastrophe, terrorist attack or industrial accident, or the infection of our systems by a malicious computer virus, our systems could be inaccessible for an extended period of time. In addition, because our information technology and telecommunications systems interface with and depend on third-party systems, we could experience service denials or failures of controls if demand for our service exceeds capacity or a third-party system fails or experiences an interruption. If our business continuity plans or system security does not sufficiently address such a business interruption, system failure or service denial, our ability to write and process new and

renewal business, provide customer service, pay claims in a timely manner or perform other necessary business functions could be significantly impaired and our business could be harmed.

Failure to maintain the security of our networks and confidential data may expose us to liability.

Our operations rely on the secure processing, storage and transmission of confidential and other information in our computer systems and networks. Computer viruses, hackers, employee misconduct and other external hazards could expose our data systems to security breaches. Our electronic transmission of personal, confidential and proprietary information to third parties with whom we have business relationships and our outsourcing of certain technology and business process functions to third parties may expose us to enhanced risk related to data security. While we attempt to develop secure data transmission capabilities with these third-party vendors and others with whom we do business, our vendors and third parties could still suffer data breaches that could result in the exposure of sensitive data and the infiltration of our computer systems. Our failure to protect sensitive personal and our proprietary information, whether owing to breaches of our own systems or those of our vendors, could result in significant monetary and reputational damages. These increased risks, and expanding regulatory requirements regarding data security, could expose us to data loss, monetary and reputational damages and significant increases in compliance costs. As a result, our ability to conduct our business could be materially and adversely affected.

We could be adversely affected if our controls to ensure compliance with guidelines, policies and legal and regulatory standards are not effective.

Our business is highly dependent on our ability to engage on a daily basis in a large number of insurance underwriting, claim processing and investment activities, many of which are highly complex. These activities often are subject to internal guidelines and policies, as well as legal and regulatory standards, including those related to privacy, anti-corruption, anti-bribery and global finance and insurance matters. Our continued expansion into new international markets has brought about additional requirements. A control system, no matter how well designed and operated, can provide only reasonable assurance that the control system's objectives will be met. If our controls are not effective, it could lead to financial loss, unanticipated risk exposure (including underwriting, credit and investment risk) or damage to our reputation.

We could be adversely affected by recent and future changes in U.S. Federal income tax laws.

Tax legislation commonly referred to as the Tax Cuts and Jobs Act, which was signed into law on December 22, 2017, fundamentally overhauled the U.S. tax system by, among other significant changes, reducing the U.S. corporate income tax rate to 21%. In the context of the taxation of U.S. property/casualty insurance companies such as the Company, the Act also modifies the loss reserve discounting rules and the proration rules that apply to reduce reserve deductions to reflect the lower corporate income tax rate. It is possible that other legislation could be introduced and enacted by the current Congress or future Congresses that could have an adverse impact on us. New regulations or pronouncements interpreting or clarifying provisions of the Act may be forthcoming. We cannot predict if, when or in what form such regulations or pronouncements may be provided, whether such guidance will have a retroactive effect or their potential impact on us.

Risks Relating to Our Investments

A significant amount of our assets is invested in fixed maturity securities and is subject to market fluctuations.

Our investment portfolio consists substantially of fixed maturity securities. As of December 31, 2019, our investment in fixed maturity securities was approximately $14.2 billion, or 72.6% of our total investment portfolio, including cash and cash equivalents. As of that date, our portfolio of fixed maturity securities consisted of the following types of securities: U.S. Government securities (5.5%); state and municipal securities (28.1%); corporate securities (29.2%); asset-backed securities (19.7%); mortgage-backed securities (11.5%) and foreign government (6.0%).

The fair value of these assets and the investment income from these assets fluctuate depending on general economic and market conditions. The fair value of fixed maturity securities generally decreases as interest rates rise. If significant inflation or an increase in interest rates were to occur, the fair value of our fixed maturity securities would be negatively impacted. Conversely, if interest rates decline, investment income earned from future investments in fixed maturity securities will be lower. Some fixed maturity securities, such as mortgage-backed and other asset-backed securities, also carry prepayment risk as a result of interest rate fluctuations. Additionally, given the low interest rate environment, we may not be able to successfully reinvest the proceeds from maturing securities at yields commensurate with our target performance goals.

The value of investments in fixed maturity securities is subject to impairment as a result of deterioration in the credit worthiness of the issuer, default by the issuer (including states and municipalities) in the performance of its obligations in respect of the securities and/or increases in market interest rates. To a large degree, the credit risk we face is a function of the economy; accordingly, we face a greater risk in an economic downturn or recession. During periods of market disruption, it may be difficult to value certain of our securities, particularly if trading becomes less frequent and/or market data becomes less

observable. There may be certain asset classes that were in active markets with significant observable data that become illiquid due to the then current financial environment. In such cases, more securities may require additional subjectivity and management judgment.

Although the historical rates of default on state and municipal securities have been relatively low, our state and municipal fixed maturity securities could be subject to a higher risk of default or impairment due to declining municipal tax bases and revenue. Many states and municipalities operate under deficits or projected deficits, the severity and duration of which could have an adverse impact on both the valuation of our state and municipal fixed maturity securities and the issuer's ability to perform its obligations thereunder. Additionally, our investments are subject to losses as a result of a general decrease in commercial and economic activity for an industry sector in which we invest, as well as risks inherent in particular securities.

Although we attempt to manage these risks through the use of investment guidelines and other oversight mechanisms and by diversifying our portfolio and emphasizing preservation of principal, our efforts may not be successful. Impairments, defaults and/or rate increases could reduce our net investment income and net realized investment gains or result in investment losses. Investment returns are currently, and will likely continue to remain, under pressure due to the continued low inflation, actions by the Federal Reserve, economic uncertainty, more generally, and the shape of the yield curve. As a result, our exposure to the risks described above could materially and adversely affect our results of operations, liquidity and financial condition.

We have invested a portion of our assets in equity securities, merger arbitrage securities, investment funds, private equity, loans and real estate related assets, which are subject to significant volatility and may decline in value.

We invest a portion of our investment portfolio in equity securities, merger arbitrage securities, investment funds, private equity, loans and real estate related assets. At December 31, 2019, our investment in these assets was approximately $4.3 billion, or 22.1%, of our investment portfolio, including cash and cash equivalents.

Merger and arbitrage trading securities were $400.8 million, or 2.1% of our investment portfolio, including cash and cash equivalents at December 31, 2019. Merger arbitrage involves investing in the securities of publicly held companies that are the targets in announced tender offers and mergers. Merger arbitrage differs from other types of investments in its focus on transactions and events believed likely to bring about a change in value over a relatively short time period, usually four months or less. Our merger arbitrage positions are exposed to the risk associated with the completion of announced deals, which are subject to regulatory as well as political and other risks.

Real estate related investments, including directly owned, investment funds and loans receivable, were $2.6 billion, or 13.2% of our investment portfolio, including cash and cash equivalents, at December 31, 2019. We also invest in real estate, financial services, energy, transportation and other investment funds. The values of these investments are subject to fluctuation based on changes in the economy and interest rates in general and the related asset valuations in particular. In addition, our investments in real estate related assets and other alternative investments are less liquid than our other investments.

These investments are subject to significant volatility as a result of the conditions in the financial and commodity markets and the global economy.

Risks Relating to Purchasing Our Securities

We are an insurance holding company and, therefore, may not be able to receive dividends in needed amounts.

As an insurance holding company, our principal assets are the shares of capital stock of our insurance company subsidiaries. We have to rely on dividends from our insurance company subsidiaries to meet our obligations for paying principal and interest on outstanding debt obligations, paying dividends to stockholders and repurchasing our shares and paying corporate expenses. The payment of dividends by our insurance company subsidiaries is subject to regulatory restrictions and will depend on the surplus and future earnings of these subsidiaries. During 2020, the maximum amount of dividends that can be paid without regulatory approval is approximately $601 million. As a result, in the future we may not be able to receive dividends from these subsidiaries at times and in amounts necessary to meet our obligations, pay dividends or repurchase shares.

Laws and regulations of the jurisdictions in which we conduct business could delay, deter or prevent an attempt to acquire control of us that stockholders might consider to be desirable, and may restrict a stockholder's ability to purchase our common stock.

Generally, United States insurance holding company laws require that, before a person can acquire control of an insurance company, prior written approval must be obtained from the insurance regulatory authorities in the state in which that insurance company is domiciled. Pursuant to applicable laws and regulations, “control” over an insurer is generally presumed to

exist if any person, directly or indirectly, owns, controls, holds the power to vote, or holds proxies representing 10% or more of the voting securities of that insurer or any parent company of such insurer. Indirect ownership includes ownership of the shares of our common stock. Thus, the insurance regulatory authorities of the states in which our insurance subsidiaries are domiciled are likely to apply these restrictions on acquisition of control to any proposed acquisition of our common stock. Some states require a person seeking to acquire control of an insurer licensed but not domiciled in that state to make a filing prior to completing an acquisition if the acquirer and its affiliates, on the one hand, and the target insurer and its affiliates, on the other hand, have specified market shares in the same lines of insurance in that state. Additionally, many foreign jurisdictions where we conduct business impose similar restrictions and requirements.

These provisions can also lead to the imposition of conditions on an acquisition that could delay or prevent its consummation. These laws may discourage potential acquisition proposals and may delay, deter or prevent a change in control of us through transactions, and in particular unsolicited transactions, that some or all of our stockholders might consider to be desirable.

Certain provisions in our organizational documents may have the effect of hindering, delaying or preventing third party takeovers and thus may prevent our stockholders from receiving premium prices for their shares in an unsolicited takeover or make it more difficult for third parties to replace our current management.

Provisions of our Restated Certificate of Incorporation and By-Laws, as well as state insurance statutes, may hinder, delay or prevent unsolicited acquisitions or changes of our control. These provisions may also have the effect of making it more difficult for third parties to cause the replacement of our current management without the concurrence of our board of directors.

These provisions include:


•	our classified board of directors and the ability of our board to increase its size and to appoint directors to fill newly created directorships;


•	the requirement that 80% of our stockholders must approve mergers and other transactions between us and the holder of 5% or more of our shares, unless the transaction was approved by our board of directors prior to such holder's acquisition of 5% of our shares; and


•	the need for advance notice in order to raise business or make nominations at stockholders' meetings.

These provisions may discourage potential acquisition proposals and may delay, deter or prevent a change in control of us through transactions, and in particular unsolicited transactions, that some or all of our stockholders might consider to be desirable.

ITEM 1B. UNRESOLVED STAFF COMMENTS

There are no unresolved written comments that were received from the SEC staff 180 days or more before the end of our fiscal year relating to our periodic or current reports under the Securities Exchange Act of 1934.

ITEM 2. PROPERTIES

W. R. Berkley and its subsidiaries own or lease office buildings or office space suitable to conduct their operations. At December 31, 2019, the Company had aggregate office space of 4,227,391 square feet, of which 1,129,970 were owned and 3,097,421 were leased.

Rental expense for the Company's operations was approximately $44,107,000, $45,778,000 and $52,925,000 for 2019, 2018 and 2017, respectively. Future minimum lease payments, without provision for sublease income, are $49,293,000 in 2020, $47,107,000 in 2021 and $189,134,000 thereafter.

ITEM 3. LEGAL PROCEEDINGS

The Company's subsidiaries are subject to disputes, including litigation and arbitration, arising in the ordinary course of their insurance and reinsurance businesses. The Company's estimates of the costs of settling such matters are reflected in its aggregate reserves for losses and loss expenses, and the Company does not believe that the ultimate outcome of such matters will have a material adverse effect on its financial condition or results of operations.

ITEM 4. MINE SAFETY DISCLOSURES

Not applicable.

PART II

ITEM 5. MARKET FOR THE REGISTRANT'S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES

The common stock of the Company is traded on the New York Stock Exchange under the symbol “WRB”. All amounts have been adjusted to reflect the 3-for-2 common stock split effected on April 2, 2019.

In 2019, the Board declared regular quarterly cash dividends of $0.10 per share in the first quarter, and $0.11 per share in each of the remaining three quarters, plus additional special dividends in the respective amounts of $0.50 per share in the second quarter and $0.75 per share in the fourth quarter. Subject to availability, the Board currently expects to continue such regular quarterly cash dividends.

The approximate number of record holders of the common stock on February 18, 2020 was 319.

The chart below shows a comparison of 5 year cumulative total return.

Comparison of 5 Year Cumulative Total Return

Assumes initial investment of $100 on January 1, 2014, with dividends reinvested.

The S&P 500® Property and Casualty Insurance Index consists of Allstate Corporation, Chubb, Ltd., Cincinnati Financial Corporation, Progressive Corporation, The Travelers Companies, Inc., and W. R. Berkley Corporation (added Dec. 2019).



		2014	2015	2016	2017	2018	2019
W. R. Berkley Corporation	Cum $	100.00	107.76	134.43	148.11	154.95	222.86
S&P 500 Index - Total Returns	Cum $	100.00	101.38	113.51	138.29	132.22	173.84
S&P 500 Property and Casualty Insurance Index	Cum $	100.00	109.53	126.73	155.10	147.83	186.07

Set forth below is a summary of the shares repurchased by the Company during the fourth quarter of 2019 and the remaining number of shares authorized for purchase by the Company during such period.



	Total Number of Shares Purchased	Average Price Paid per Share	Total Number of Shares Purchased as Part of Publicly Announced Plans or Programs	Maximum Number of Shares that may yet be Purchased Under the Plans or Programs
October 2019	—	—	—	13,367,095
November 2019	51,163	67.77	51,163	13,315,932
December 2019	217,909	67.72	217,909	13,098,023

ITEM 6. SELECTED FINANCIAL DATA



	As of and for the Year Ended December 31,
(In thousands, except per share data)	2019			2018			2017			2016			2015
Net premiums written	$	6,863,499		$	6,433,227		$	6,260,508		$	6,423,913		$	6,189,515
Net premiums earned	6,633,288			6,371,505			6,311,419			6,293,348			6,040,609
Net investment income	645,614			674,235			575,788			564,163			512,645
Net realized and unrealized gains on investments	120,703			154,488			335,858			267,005			92,324
Revenues from non-insurance businesses	406,541			372,985			326,165			390,348			421,102
Insurance service fees	92,680			117,757			134,729			138,944			139,440
Total revenues	7,902,196			7,691,651			7,684,764			7,654,184			7,206,457
Interest expense	153,409			157,185			147,297			140,896			130,946
Income before income taxes	852,920			812,094			772,770			896,438			732,030
Income tax expense	(168,935		)	(163,028		)	(219,433		)	(292,953		)	(227,923		)
Noncontrolling interests	(2,041		)	(8,317		)	(4,243		)	(1,569		)	(413		)
Net income to common stockholders	681,944			640,749			549,094			601,916			503,694
Data per common share:
Net income per basic share	3.58			3.37			2.93			3.27			2.71
Net income per diluted share	3.52			3.33			2.84			3.12			2.58
Common stockholders’ equity	33.12			29.72			29.69			27.76			24.87
Cash dividends declared	1.73			1.39			1.03			1.01			0.31
Weighted average shares outstanding:
Basic	190,722			190,048			187,265			183,977			186,060
Diluted	193,521			192,395			193,527			192,830			195,284
Investments	$	18,473,674		$	17,723,089		$	17,450,508		$	16,649,792		$	15,351,467
Total assets	26,643,428			24,895,977			24,299,917			23,364,844			21,730,967
Reserves for losses and loss expenses	12,583,249			11,966,448			11,670,408			11,197,195			10,669,150
Senior notes and other debt	1,427,575			1,882,028			1,769,052			1,760,595			1,844,621
Subordinated debentures	1,198,704			907,491			728,218			727,630			340,320
Common stockholders’ equity	6,074,939			5,437,851			5,411,344			5,047,208			4,600,246

ITEM 7. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

Overview

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 business segments of the property and casualty business: Insurance and Reinsurance & Monoline Excess. Our decentralized structure provides us with the flexibility to respond quickly and efficiently to local or specific market conditions and to pursue specialty business niches. It also allows us to be closer to our customers in order to better understand their individual needs and risk characteristics. While providing our business units with certain operating autonomy, our structure allows us to capitalize on the benefits of economies of scale through centralized capital, investment, reinsurance and enterprise risk management, and actuarial, financial and corporate legal staff support. The Company's primary sources of revenues and earnings are its insurance operations and its investments.

An important part of our strategy is to form new operating units to capitalize on various business opportunities. Over the years, the Company has formed numerous new operating units that are focused on important parts of the economy in the U.S., including healthcare, cyber security, energy and agriculture, and on growing international markets, including the Asia-Pacific region, South America and Mexico.

The profitability of the Company’s insurance business is affected primarily by the adequacy of premium rates. The ultimate adequacy of premium rates is not known with certainty at the time an insurance policy is issued because premiums are determined before claims are reported. The ultimate adequacy of premium rates is affected mainly by the severity and frequency of claims, which are influenced by many factors, including natural and other disasters, regulatory measures and court decisions that define and change the extent of coverage and the effects of economic or social inflation on the amount of compensation for injuries or losses. General insurance prices are also influenced by available insurance capacity, i.e., the level of capital employed in the industry, and the industry’s willingness to deploy that capital.

The Company’s profitability is also affected by its investment income and investment gains. The Company’s invested assets are invested principally in fixed maturity securities. The return on fixed maturity securities is affected primarily by general interest rates, as well as the credit quality and duration of the securities. Returns available on fixed maturity investments have been at low levels for an extended period.

The Company also invests in equity securities, merger arbitrage securities, investment funds, private equity, loans and real estate related assets. The Company's investments in investment funds and its other alternative investments have experienced, and the Company expects to continue to experience, greater fluctuations in investment income.

On April 2, 2019, a 3-for-2 common stock split was paid in the form of a stock dividend to holders of record as of March 14, 2019. Shares outstanding and per share amounts in this Form 10-K reflect this 3-for-2 common stock split effected on April 2, 2019.

Commencing with the first quarter of 2019, the Company renamed the Reinsurance segment to Reinsurance & Monoline Excess, and reclassified the monoline excess business from the Insurance segment. The reclassified business includes operations that solely retain risk on an excess basis. Reclassifications have been made to the Company's prior periods financial information in this Form 10-K to conform with this presentation.

Critical Accounting Estimates

The following presents a discussion of accounting policies and estimates relating to reserves for losses and loss expenses, assumed reinsurance premiums and other-than-temporary impairments of investments. Management believes these policies and estimates are the most critical to its operations and require the most difficult, subjective and complex judgments.

Reserves for Losses and Loss Expenses. 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.

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 other things, 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 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.

Reserves do not represent a certain 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 reserves are well tested over time, the major assumptions about anticipated loss emergence patterns are subject to uncertainty. 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. Because setting reserves is inherently uncertain, the Company cannot provide assurance that its current reserves will prove adequate in light of subsequent events.

Loss reserves included in the Company’s financial statements represent management’s best estimates based upon an actuarially derived point estimate and other considerations. The Company uses a variety of actuarial techniques and methods to derive an actuarial point estimate for each operating unit. These methods include paid loss development, incurred loss development, paid and incurred Bornhuetter-Ferguson methods and frequency and severity methods. In circumstances where one actuarial method is considered more credible than the others, that method is used to set the point estimate. For example, the paid loss and incurred loss development methods rely on historical paid and incurred loss data. For new lines of business, where there is insufficient history of paid and incurred claims data, or in circumstances where there have been significant changes in claim practices, the paid and incurred loss development methods would be less credible than other actuarial methods. The actuarial point estimate may also be based on a judgmental weighting of estimates produced from each of the methods considered. Industry loss experience is used to supplement the Company’s own data in selecting “tail factors” and in areas where the Company’s own data is limited. The actuarial data is analyzed by line of business, coverage and accident or policy year, as appropriate, for each operating unit.

The establishment of the actuarially derived loss reserve point estimate also includes consideration of qualitative factors that may affect the ultimate losses. These qualitative considerations include, among others, the impact of re-underwriting initiatives, changes in the mix of business, changes in distribution sources and changes in policy terms and conditions. Examples of changes in terms and conditions that can have a significant impact on reserve levels are the use of aggregate policy limits, the expansion of coverage exclusions, whether or not defense costs are within policy limits, and changes in deductibles and attachment points.

The key assumptions used to arrive at the best estimate of loss reserves are the expected loss ratios, rate of loss cost inflation, and reported and paid loss emergence patterns. Expected loss ratios represent management’s expectation of losses at the time the business is priced and written, before any actual claims experience has emerged. This expectation is a significant determinant of the estimate of loss reserves for recently written business where there is little paid or incurred loss data to consider. Expected loss ratios are generally derived from historical loss ratios adjusted for the impact of rate changes, loss cost trends and known changes in the type of risks underwritten. Expected loss ratios are estimated for each key line of business within each operating unit. Expected loss cost inflation is particularly important for the long-tail lines, such as excess casualty, and claims with a high medical component, such as workers’ compensation. Reported and paid loss emergence patterns are used to project current reported or paid loss amounts to their ultimate settlement value. Loss development factors are based on the historical emergence patterns of paid and incurred losses, and are derived from the Company’s own experience and industry data. The paid loss emergence pattern is also significant to excess and assumed workers’ compensation reserves because those reserves are discounted to their estimated present value based upon such estimated payout patterns. Management believes the estimates and assumptions it makes in the reserving process provide the best estimate of the ultimate cost of settling claims and

related expenses with respect to insured events which have occurred; however, different assumptions and variables could lead to significantly different reserve estimates.

Loss frequency and severity are measures of loss activity that are considered in determining the key assumptions described in our discussion of loss and loss expense reserves, including expected loss ratios, rate of loss cost inflation and reported and paid loss emergence patterns. Loss frequency is a measure of the number of claims per unit of insured exposure, and loss severity is a measure of the average size of claims. Factors affecting loss frequency include the effectiveness of loss controls and safety programs and changes in economic activity or weather patterns. Factors affecting loss severity include changes in policy limits, retentions, rate of inflation and judicial interpretations.

Another factor affecting estimates of loss frequency and severity is the loss reporting lag, which is the period of time between the occurrence of a loss and the date the loss is reported to the Company. The length of the loss reporting lag affects our ability to accurately predict loss frequency (loss frequencies are more predictable for lines with short reporting lags) as well as the amount of reserves needed for incurred but not reported losses (less IBNR is required for lines with short reporting lags). As a result, loss reserves for lines with short reporting lags are likely to have less variation from initial loss estimates. For lines with short reporting lags, which include commercial automobile, primary workers’ compensation, other liability (claims-made) and property business, the key assumption is the loss emergence pattern used to project ultimate loss estimates from known losses paid or reported to date. For lines of business with long reporting lags, which include other liability (occurrence), products liability, excess workers’ compensation and liability reinsurance, the key assumption is the expected loss ratio since there is often little paid or incurred loss data to consider. Historically, the Company has experienced less variation from its initial loss estimates for lines of businesses with short reporting lags than for lines of business with long reporting lags.

The key assumptions used in calculating the most recent estimate of the loss reserves are reviewed each quarter and adjusted, to the extent necessary, to reflect the latest reported loss data, current trends and other factors observed. If the actual level of loss frequency and severity are higher or lower than expected, the ultimate losses will be different than management’s estimate. The following table reflects the impact of changes (which could be favorable or unfavorable) in frequency and severity, relative to our assumptions, on our loss estimate for claims occurring in 2019:



(In thousands)	Frequency (+/-)
Severity (+/-)	1%		5%		10%
1%	$	81,566	$	245,508	$	450,437
5%	245,508		415,944		628,988
10%	450,437		628,988		852,178

Our net reserves for losses and loss expenses of approximately $10.7 billion as of December 31, 2019 relate to multiple accident years. Therefore, the impact of changes in frequency or severity for more than one accident year could be higher or lower than the amounts reflected above. The impact of such changes would likely be manifested gradually over the course of many years, as the magnitude of the changes became evident.

Approximately $2.5 billion, or 23%, of the Company’s net loss reserves as of December 31, 2019 relate to the Reinsurance & Monoline Excess segment. There is a higher degree of uncertainty and greater variability regarding estimates of excess workers' compensation and assumed reinsurance loss reserves. In the case of excess workers’ compensation, our policies generally attach at $1 million or higher. The claims which reach our layer therefore tend to involve the most serious injuries and many remain open for the lifetime of the claimant, which extends the claim settlement tail. These claims also occur less frequently but tend to be larger than primary claims, which increases claim variability. In the case of assumed reinsurance our loss reserve estimates are based, in part, upon information received from ceding companies. If information received from ceding companies is not timely or correct, the Company’s estimate of ultimate losses may not be accurate. Furthermore, due to delayed reporting of claim information by ceding companies, the claim settlement tail for assumed reinsurance is also extended. Management considers the impact of delayed reporting and the extended tail in its selection of loss development factors for these lines of business.

Information received from ceding companies is used to set initial expected loss ratios, to establish case reserves and to estimate reserves for incurred but not reported losses on assumed reinsurance business. This information, which is generally provided through reinsurance intermediaries, is gathered through the underwriting process and from periodic claim reports and other correspondence with ceding companies. The Company performs underwriting and claim audits of selected ceding companies to determine the accuracy and completeness of information provided to the Company. The information received from the ceding companies is supplemented by the Company’s own loss development experience with similar lines of business as well as industry loss trends and loss development benchmarks.

Following is a summary of the Company’s reserves for losses and loss expenses by business segment as of December 31, 2019 and 2018:



(In thousands)	2019		2018
Insurance	$	8,193,381	$	7,727,447
Reinsurance & Monoline Excess	2,504,617		2,521,436
Net reserves for losses and loss expenses	10,697,998		10,248,883
Ceded reserves for losses and loss expenses	1,885,251		1,717,565
Gross reserves for losses and loss expenses	$	12,583,249	$	11,966,448

Following is a summary of the Company’s net reserves for losses and loss expenses by major line of business as of December 31, 2019 and 2018:



(In thousands)	Reported Case Reserves		Incurred But Not Reported		Total
December 31, 2019
Other liability	$	1,421,378	$	2,522,957	$	3,944,335
Workers’ compensation (1)	918,619		964,102		1,882,721
Professional liability	399,411		713,433		1,112,844
Commercial automobile	412,036