UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

_____________________________________________ 

FORM 10-K

_____________________________________________ 

(Mark One)

☒ Annual Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

For the fiscal year ended December 31, 2023

OR

☐ Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Commission File No. 1-5998

_____________________________________________ 

Marsh & McLennan Companies, Inc.

(Exact name of registrant as specified in its charter)

Delaware	36-2668272
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification No.)

1166 Avenue of the Americas

New York, New York 10036-2774

(Address of principal executive offices; Zip Code)

(212) 345-5000

Registrant’s telephone number, including area code

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 $1.00 per share	MMC	New York Stock Exchange
		Chicago Stock Exchange

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes  ý    No  ¨

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

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  ý    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  ý    No   ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or a smaller reporting Company. See the definitions of "large accelerated filer," "accelerated filer" and "smaller reporting Company" in Rule 12b-2 of the Exchange Act. (Check one):

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 Exchange Act).     Yes  ☐    No  ý

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report.  Yes  ☒    No  ¨

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ¨

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive- based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b). ¨

As of June 30, 2023, the aggregate market value of the registrant's common stock held by non-affiliates of the registrant was approximately $92,849,878,606 computed by reference to the closing price of such stock as reported on the New York Stock Exchange on June 30, 2023.

As of February 8, 2024, there were outstanding 491,656,196 shares of common stock, par value $1.00 per share, of the registrant.

Auditor Name: Deloitte & Touche LLP Auditor Location: New York, New York Auditor Firm ID: 34

DOCUMENTS INCORPORATED BY REFERENCE

Portions of Marsh & McLennan Companies, Inc.’s Notice of Annual Meeting and Proxy Statement for the 2024 Annual Meeting of Stockholders (the "2024 Proxy Statement") are incorporated by reference in Part III of this Form 10-K.

INFORMATION CONCERNING FORWARD-LOOKING STATEMENTS

This Annual Report on Form 10-K contains "forward-looking statements," as defined in the Private Securities Litigation Reform Act of 1995. These statements, which express management's current views concerning future events or results, use words like "anticipate," "assume," "believe," "continue," "estimate," "expect," "intend," "plan," "project" and similar terms, and future or conditional tense verbs like "could," "may," "might," "should," "will" and "would".

Forward-looking statements are subject to inherent risks and uncertainties that could cause actual results to differ materially from those expressed or implied in our forward-looking statements. Factors that could materially affect our future results include, among other things:

•the impact of geopolitical or macroeconomic conditions on us, our clients and the countries and industries in which we operate, including from multiple major wars, escalating conflict throughout the Middle East and rising tension in the South China Sea, slower GDP growth or recession, lower interest rates, capital markets volatility and inflation;

•the impact from lawsuits or investigations arising from errors and omissions, breaches of fiduciary duty or other claims against us in our capacity as a broker or investment advisor, including claims related to our investment business’ ability to execute timely trades;

•the increasing prevalence of ransomware, supply chain and other forms of cyberattacks, and their potential to disrupt our operations or the operations of our third party vendors, and result in the disclosure of confidential client or company information;

•the financial and operational impact of complying with laws and regulations, including domestic and international sanctions regimes, anti-corruption laws such as the U.S. Foreign Corrupt Practices Act, U.K. Anti Bribery Act and cybersecurity, data privacy and artificial intelligence regulations;

•our ability to attract, retain and develop industry leading talent;

•our ability to compete effectively and adapt to competitive pressures in each of our businesses, including from disintermediation as well as technological change, digital disruption and other types of innovation such as artificial intelligence;

•our ability to manage potential conflicts of interest, including where our services to a client conflict, or are perceived to conflict, with the interests of another client or our own interests;

•the impact of changes in tax laws, guidance and interpretations, such as the implementation of the Organization for Economic Cooperation and Development international tax framework, or the increasing number of disagreements with and challenges by tax authorities in the current global tax environment; and

•the regulatory, contractual and reputational risks that arise based on insurance placement activities and insurer revenue streams.

The factors identified above are not exhaustive. Further information concerning Marsh McLennan and its businesses, including information about factors that could materially affect our results of operations and financial condition, is contained in the Company's filings with the Securities and Exchange Commission, including the "Risk Factors" section in Part I, Item 1A of this report and the "Management’s Discussion and Analysis of Financial Condition and Results of Operations" section in Part II, Item 7 of this report. Marsh McLennan and its subsidiaries operate in a dynamic business environment in which new risks emerge frequently. Accordingly, we caution readers not to place undue reliance on any forward-looking statements, which are based only on information currently available to us and speak only as of the dates on which they are made. The Company undertakes no obligation to update or revise any forward-looking statement to reflect events or circumstances arising after the date on which it is made.

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TABLE OF CONTENTS

Information Concerning Forward-Looking Statements		i
PART I
Item 1 —	Business	1
Item 1A —	Risk Factors	13
Item 1B —	Unresolved Staff Comments	32
Item 1C —	Cybersecurity	32
Item 2 —	Properties	34
Item 3 —	Legal Proceedings	34
Item 4 —	Mine Safety Disclosures	34
PART II
Item 5 —	Market for the Company’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities	35
Item 6 —	[Reserved]	35
Item 7 —	Management’s Discussion and Analysis of Financial Condition and Results of Operations	36
Item 7A —	Quantitative and Qualitative Disclosures About Market Risk	55
Item 8 —	Financial Statements and Supplementary Data	57
Item 9 —	Changes in and Disagreements with Accountants on Accounting and Financial Disclosure	113
Item 9A —	Controls and Procedures	113
Item 9B —	Other Information	115
PART III
Item 10 —	Directors, Executive Officers and Corporate Governance	116
Item 11 —	Executive Compensation	116
Item 12 —	Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters	116
Item 13 —	Certain Relationships and Related Transactions, and Director Independence	116
Item 14 —	Principal Accountant Fees and Services	116
PART IV
Item 15 —	Exhibits and Financial Statement Schedules	117
Item 16 —	Form 10-K Summary	129
Signatures		130

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PART I

Item 1.    Business.

References in this report to "we", "us" and "our" are to Marsh & McLennan Companies, Inc. and its consolidated subsidiaries (the "Company" or "Marsh McLennan"), unless the context otherwise requires.

GENERAL

Marsh McLennan is the world's leading professional services firm in the areas of risk, strategy and people. We help clients build the confidence to thrive through the power of perspective of our four market-leading businesses. With annual revenue of $23 billion, we have more than 85,000 colleagues advising clients in over 130 countries.

Marsh provides data-driven risk advisory services and insurance solutions to commercial and consumer clients. Guy Carpenter develops advanced risk, reinsurance and capital strategies that help clients grow profitably and pursue emerging opportunities. Mercer delivers advice and technology-driven solutions that help organizations redefine the world of work, reshape retirement and investment outcomes, and unlock health and well-being for a changing workforce. Oliver Wyman Group serves as a critical strategic, economic and brand advisor to private sector and governmental clients. Our four businesses also collaborate together to deliver new solutions to help clients manage complex and interconnected risks.

The Company conducts business through two segments:

•Risk and Insurance Services includes risk management activities (risk advice, risk transfer and risk control and mitigation solutions) as well as insurance and reinsurance broking and services. The Company conducts business in this segment through Marsh and Guy Carpenter.

•Consulting includes health, wealth and career advice, solutions and products, and specialized management, strategic, economic and brand consulting services. The Company conducts business in this segment through Mercer and Oliver Wyman Group.

We describe our current segments in further detail below. We provide financial information about our segments in our consolidated financial statements included under Part II, Item 8 of this report.

OUR BUSINESSES

RISK AND INSURANCE SERVICES

The Risk and Insurance Services segment generated approximately 62% of the Company's total revenue in 2023 and employs approximately 49,300 colleagues worldwide. The Company conducts business in this segment through Marsh and Guy Carpenter.

MARSH

Marsh is the world's leading insurance broker and risk advisor, serving companies, institutions and individuals. From its founding in 1871 to the present day, Marsh has demonstrated a commitment to thought leadership, innovation and insurance expertise to meet its clients’ needs. Marsh’s pioneering contributions include introducing the practice of client representation through brokerage, the discipline of risk management, the globalization of risk management services and the development of service platforms that identify, quantify, mitigate and transfer risk.

Currently, approximately 45,800 Marsh colleagues provide risk management, insurance broking, insurance program management, risk consulting, analytical modeling and alternative risk financing services to a wide range of businesses, government entities, professional service organizations and individuals in over 130 countries. Marsh generated approximately 51% of the Company's total revenue in 2023.

Insurance Broking and Risk Advisory

In its core insurance broking and risk advisory business, Marsh employs a team approach to identify, quantify and address clients' risk management and insurance needs. Marsh’s product and service offerings include risk analysis, insurance program design and placement, insurance program support and administration, claims support and advocacy, alternative risk strategies and a wide array of risk analysis and risk management consulting services. Clients benefit from Marsh’s advanced analytics, deep technical expertise, specialty and industry knowledge, collaborative global culture and the ability to develop innovative solutions and products. The firm’s resources also include nearly three dozen specialty and industry practices, including cyber, construction, renewable energy, healthcare, and financial and professional service practices, along with ESG products such as

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a D&O insurance initiative recognizing U.S. based clients with superior ESG frameworks, and an established employee health & benefits business.

Marsh provides services to clients of all sizes, including large multinational companies ("Risk Management"), high growth middle-market businesses ("Corporate"), small commercial enterprises and high net-worth private clients, and affinity group members ("Commercial & Consumer"). Marsh's segments are designed to build stronger value propositions and operating models to optimize solutions and services for clients depending on their needs.

Risk Management. Marsh has an extensive global footprint and market-leading advisory and placement services that benefit large domestic and international companies and institutions facing complex risk exposures. These clients are also supported by Marsh’s robust analytics and a growing digital experience.

In addition, Marsh’s largest global clients are serviced by Marsh Multinational, a dedicated team of colleagues from around the world focused on delivering service excellence and insurance solutions to clients wherever they are located. Marsh is digitizing the client experience through tools such as LINQ, Marsh’s account and service application; Blue[i], a suite of analytics tools for clients; and Bluestream, a digital brokerage platform that enables clients to provide insurance to their customers or suppliers in a B2B2C distribution model. Marsh provides global expertise and an intimate knowledge of local markets, helping clients navigate local regulatory environments to address the worldwide risk issues that confront them.

•Marsh Specialty is an integrated and globally coordinated team of experts who provides clients in highly specialized industry and product areas with data driven insights, service, advice and access to global insurance markets. These specialists support clients who require advice and support across aviation & space, credit specialties, construction, energy & power, financial & professional services (FINPRO), marine & cargo, and private equity, mergers & acquisitions (PEMA).

Corporate. Middle market clients are served by Marsh’s brokerage operations globally; this segment is also serviced by Marsh & McLennan Agency (MMA) in the United States (U.S.).

•Marsh McLennan Agency (MMA) provides business insurance, employee health and benefits, retirement and wealth management, and private client insurance solutions to individuals and mid-market organizations. MMA advises on insurance program structure and market dynamics, along with industry expertise and transactional capability. Since its first acquisition in 2009, MMA has acquired more than 100 agencies.

Commercial & Consumer. Clients in this market segment typically face less complex risks and are served by Marsh’s innovative product and placement offerings and growing capabilities in digitally enabled distribution and administration.

•Victor Insurance Managers (Victor) is one of the largest underwriting managers of professional liability, catastrophe, and other specialty insurance programs worldwide. In the U.S., Victor Insurance Managers (US) and ICAT Managers underwrites, solicits, sells and services coverages through a national third-party distribution network of licensed brokers and agents. Through its Victor Small Business platform, Victor deploys cloud-based technology to enable independent insurance agents, on behalf of their small business clients, to obtain online quotes from multiple insurance providers and bind property and casualty and workers compensation insurance policies in real time. Victor also manages Torrent Technologies, the nation’s largest service provider to the National Flood Insurance Program (NFIP), serving the NFIP both directly and through the NFIP’s Write Your Own (WYO) program. Victor Insurance Managers (Canada), a leading managing general agent in Canada, delivers professional liability and construction insurance and other P&C programs and administers group and retiree benefits programs and claims handling operations for individuals, organizations and businesses. Victor also has a business in the UK, the Netherlands, Italy, Germany and Australia.

•Marsh Affinity focuses on insurance programs sold to insureds or vendors through a corporate sponsor using an affinity distribution model.

•High Net Worth (HNW). Individual high net worth clients and family offices are serviced by MMA in the U.S. and other Marsh personal lines businesses globally. These businesses provide a single-source solution for high net worth clients and are dedicated to sourcing protections across a broad spectrum of risk. Using a consultative approach, Marsh's HNW practices analyze exposures and customize programs to cover individual clients with complex asset portfolios.

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Additional Services and Adjacent Businesses

In addition to insurance broking, Marsh provides certain other specialist advisory or placement services:

Marsh Advisory is a global practice comprising specialists who use data and analytics, including through Marsh’s Blue[i] digital analytics platform. Marsh Advisory’s three main service areas (Consulting, Claims, and Analytics) advise clients on existing and emerging risk exposures, protecting critical business activities and developing strategies to optimize total cost of risk.

Marsh Captive Solutions, a prominent part of the Marsh Specialty and Global Placement practice, helps organizations of all sizes retain risks through comprehensive and innovative captive solutions. This team is comprised of captive consultants, actuaries and captive management professionals which offer complete, end-to-end captive management services.

Bowring Marsh is an international placement broker. This unit’s core strategy is to modernize risk transfer advice and solutions for clients. This is executed through a combination of data solutions, capacity creation vehicles, segmentation, placement platforms (on-shoring solutions within the network), and improved operational efficiency – all designed to yield a better client outcome and experience. The products Bowring Marsh places include property, casualty, terrorism, product recall, and special risks.

Mercer Marsh Benefits provides health benefits brokerage and consulting services to clients of all sizes in numerous countries across the globe, outside of the U.S. As described below, Mercer and Marsh go to market together to provide strategic advice and services to help clients minimize risk, optimize benefits structure, drive efficiencies and maximize employee engagement.

Services for Insurers

Marsh's Insurer Consulting Group (ICG) provides services to insurance carriers. Through Marsh's patented electronic platform, MarketConnect, and sophisticated data analysis, ICG provides insurers with individualized preference setting and risk identification capabilities, as well as detailed performance data and metrics. Insurer consulting teams review performance metrics and preferences with insurers and provide customized consulting services to insurers designed to improve business planning and strategy implementation. ICG services are designed to improve the product offerings available to clients, assist insurers in identifying new opportunities and enhance insurers’ operational efficiency. The scope and nature of the services vary by insurer and by geography.

GUY CARPENTER

Guy Carpenter, the Company’s reinsurance intermediary and advisor, generated approximately 11% of the Company's total revenue in 2023. Currently, approximately 3,500 Guy Carpenter colleagues provide clients with a combination of specialized reinsurance broking expertise, strategic advisory services and analytics solutions. Guy Carpenter creates and executes reinsurance and risk management solutions for clients worldwide through risk assessment analytics, actuarial services, highly-specialized product knowledge and trading relationships with reinsurance markets. Client services also include contract and claims management, reinsurance accounting and fiduciary services.

Acting as a broker or intermediary on all classes of reinsurance, Guy Carpenter places two main types of property casualty and life / health reinsurance: treaty reinsurance, which involves the transfer of a portfolio of risks; and facultative reinsurance, which involves the transfer of part or all of the coverage provided by a single insurance policy.

Guy Carpenter provides reinsurance services in a broad range of centers of excellence, segments and specialties including: Automobile / Motor, Aviation, Captives, Crop/Agriculture, Cyber, Engineering / Construction, Financial Lines, InsurTech, Life / Accident / Health, Marine and Energy, Medical Professional, Personal Lines, Mortgage, Political Risk & Trade Credit, Primary & Excess Casualty, Managing General Agents and Program Manager Solutions, Property, Public Sector, Regional / Mutual, Retrocessional Reinsurance, Surety, Terror, and Workers Compensation / Employer Liability.

Guy Carpenter also offers clients alternatives to traditional reinsurance, including industry loss warranties and, through its licensed affiliates, capital markets alternatives such as transferring catastrophe risk through the issuance of insurance-linked securities. GC Securities, the Guy Carpenter division of MMC Securities LLC and MMC Securities (Europe) Limited, offer corporate finance solutions, including mergers & acquisitions advice and private debt and equity capital raising, and capital markets-based risk transfer solutions that complement Guy Carpenter's strong industry relationships, analytical capabilities and reinsurance expertise.

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Guy Carpenter also provides its clients with reinsurance-related services, including actuarial, enterprise risk management, financial and regulatory consulting, portfolio analysis and advice on the efficient use of capital. Guy Carpenter's Global Strategic Advisory ("GSA") unit helps clients better understand and quantify the uncertainties inherent in their businesses. Working in close partnership with Guy Carpenter account executives, GSA specialists help support clients' critical decisions in numerous areas, including reinsurance utilization, catastrophe exposure portfolio management, new product and market development, rating agency, regulatory and account impacts, loss reserve risk, capital adequacy and return on capital.

Compensation for Services in Risk and Insurance Services

Marsh and Guy Carpenter are compensated for brokerage and consulting services through commissions and fees. Commission rates and fees vary in amount and can depend on a number of factors, including the type of insurance or reinsurance coverage provided, the particular insurer or reinsurer selected, and the capacity in which the broker acts and negotiates with clients. In addition to compensation from its clients, Marsh also receives other compensation, separate from retail fees and commissions, from insurance companies. This other compensation includes, among other things, payments for consulting and analytics services provided to insurers; compensation for administrative and other services (including fees for underwriting services and services provided to or on behalf of insurers relating to the administration and management of quota shares, panels and other facilities in which insurers participate); and contingent commissions, which are paid by insurers based on factors such as volume or profitability of Marsh's placements, primarily driven by MMA and parts of Marsh's international operations.

Marsh and Guy Carpenter receive interest income on certain funds (such as premiums and claims proceeds) held in a fiduciary capacity for others. For a more detailed discussion of revenue sources and factors affecting revenue in our Risk and Insurance Services segment, refer to Part II, Item 7 ("Management's Discussion and Analysis of Financial Condition and Results of Operations") of this report.

CONSULTING

The Company's Consulting segment generated approximately 38% of the Company's total revenue in 2023 and employs approximately 31,300 colleagues worldwide. The Company conducts business in this segment through Mercer and Oliver Wyman Group.

MERCER

Mercer is a leading provider in delivering advice, solutions and products that help organizations meet the health, wealth and career needs of a changing workforce. Mercer has approximately 24,500 colleagues based in 48 countries. Clients include a majority of the companies in the Fortune 1000 and FTSE 100, as well as medium- and small-market organizations, public sector entities and individual customers. Mercer generated approximately 24% of the Company's total revenue in 2023.

Mercer operates in the following areas:

Health. Mercer helps public and private sector employers design and manage employee health and welfare programs; administer health benefits and flexible benefits programs, including benefits outsourcing; engage employees with their health benefits through a digital experience; and comply with local benefits-related regulations. Mercer provides a range of advice and solutions to clients, which, depending on the engagement, may include: total health and wellness management strategies; global health brokerage solutions; vendor performance and audit; life and disability management; and measurement of healthcare provider performance. These services are provided through fee-based consulting as well as commission-based brokerage services in connection with the selection of insurance companies and healthcare providers.

Mercer also provides consulting and actuarial services to U.S. state governments to support the purchase of healthcare through state Medicaid programs. Mercer offers clients tools to enhance employee engagement with their health benefits through its DarwinSM platform.

Outside of the U.S., Mercer and Marsh go to market together for Health benefits brokerage and consulting under the Mercer Marsh BenefitsSM (MMB) brand, as described above.

Wealth. Through its Wealth business, Mercer assists clients worldwide in the design, governance and risk management of defined benefit, defined contribution, hybrid retirement plans and other pools of assets, and with investment of those assets.

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Mercer provides actuarial consulting, investment consulting, investment management and related services to the sponsors and trustees of pension plans, master trusts, foundations, endowments, sovereign wealth funds, insurance companies and family offices. Mercer also provides investment consulting and investment management services to U.S. public sector clients, financial intermediaries and individuals. Mercer provides retirement plan outsourcing, including administration and delivery of defined benefit and defined contribution retirement benefits.

Mercer's investment consulting and investment management services (investment management services may also be referred to as "investment solutions," "delegated solutions," "fiduciary management" or "outsourced Chief Investment Officer (OCIO) services") cover a range of stages of the investment process, from investment research (through its Mercer-Insight service), asset allocation and implementation of investment strategies to ongoing portfolio management services. Mercer provides these services primarily to institutional and other sophisticated investors including retirement plans (e.g., defined benefit and defined contribution), master trusts, endowments and foundations, sovereign wealth funds, U.S. public sector clients, insurance companies and family offices, as well as wealth managers and other financial intermediaries, primarily through manager of manager strategies and funds sponsored and managed by Mercer. Mercer’s clients invest in both traditional asset classes (e.g., equities, fixed income and cash equivalents) and alternative or private market strategies (e.g., private equity, private debt, real estate, other real assets and hedge funds). As of December 31, 2023, Mercer and its global affiliates had assets under management of approximately $420 billion worldwide.

Mercer also provides services to individual retail clients, including financial planning, high net worth risk solutions and other discretionary investment services.

Career. Mercer advises organizations on the engagement, skill assessment, management and reward of employees; the design of executive remuneration programs; people and workforce strategies during business transformation; improvement of human resource (HR) effectiveness; and the implementation of digital and cloud-based Human Resource Information Systems. In addition, through proprietary survey data and decision support tools, Mercer provides clients with human capital information and analytical capabilities to improve strategic human capital decision making. Mercer’s Career products include solutions relating to rewards, mobility, engagement, workforce analytics and assessments. Mercer helps clients plan and implement HR programs and other organizational changes designed to maximize employee engagement.

Mercer also provides advice relating to people and benefits-related issues to buyers and sellers in a variety of types of M&A transactions.

OLIVER WYMAN GROUP

With more than 6,800 professionals and offices in over 30 countries, Oliver Wyman Group delivers advisory services to clients through three operating units, each of which is a leader in its field: Oliver Wyman, Lippincott and NERA Economic Consulting. Oliver Wyman Group generated approximately 14% of the Company's total revenue in 2023.

Oliver Wyman is a global leader in management consulting and combines deep industry knowledge with specialized expertise in strategy, operations, risk management and organization transformation. The firm works with clients around the world to help optimize their business, improve their operations and risk profile, and accelerate their organizational performance to seize attractive opportunities. Industry groups include:

•Automotive and Manufacturing Industries

•Communications, Media & Technology

•Energy and Natural Resources

•Financial Services (including corporate and institutional banking, public policy, and retail and business banking)

•Insurance and Asset Management

•Health and Life Sciences

•Public Sector

•Private Capital

•Retail & Consumer Goods

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•Transportation Services (including aviation; aerospace and defense; rail; express, postal and third party logistics; services, including travel and leisure, environmental and facility management, and business and tech services; and CAVOK, which provides technical consulting and market forecasting services)

Oliver Wyman overlays its industry knowledge with expertise in the following functional specializations:

•Actuarial. Oliver Wyman’s Actuarial Practice uses mathematical and statistical modeling skills and qualitative assessment methodologies to assist clients in evaluating and addressing risk.

•Climate and Sustainability. Oliver Wyman assists clients in cutting through complex climate systems and solving for operational efficiencies. Oliver Wyman helps clients discover new business opportunities, create new pathways, and respond to climate risk, to make needed changes commercially compelling.

•Finance and Risk. Oliver Wyman provides leading financial institutions with custom solutions and insights covering all aspects of risk and finance functions, including credit risk, market risks, asset and liability management and liquidity risks, and non-financial risks, together with integrated risk management topics, such as aggregated risk analyses, business applications and culture and organization.

•Restructuring. Oliver Wyman offers a complete management solution and "one-stop-shop" approach to turning around companies, providing strategic, operational, and financial restructuring advice.

•Digital. Oliver Wyman partners with clients to address their digital challenges, blending the power of digital with deep industry expertise. By building strong capabilities and culture, Oliver Wyman accelerates and embeds digital transformation, working collaboratively with clients’ leaders, employees, stakeholders, and customers to jointly define, design, and achieve lasting results.

•Operations. Oliver Wyman helps organizations leverage their operations for a competitive advantage using a comprehensive set of capabilities, including performance improvement, digital operations strategy, and risk management.

•People and Organizational Performance. Oliver Wyman's People and Organizational Performance capability brings together deep functional expertise and industry knowledge to enable the whole organization to work in service of its strategic vision and to address the most pressing organizational, people, and change issues.

•Payments. Oliver Wyman draws on years of industry-shaping work in the Financial Services and Retail industries, deep digital expertise, and renowned research partners in its Celent® business, to help clients - from banks/issuers, to payments providers, to retailers - to build growth strategies, form effective partnerships, optimize costs, and manage risk.

•Pricing, Sales, and Marketing. Oliver Wyman helps organizations drive top-line and margin growth through outstanding strategy and decision making on pricing, marketing optimization, and best practices on sales effectiveness.

•Customer First. Oliver Wyman helps bring together capabilities required to identify customer and business growth, conduct detailed business design, build and launch a business, and maintain a focus on realizing growth while de-risking delivery.

•Performance Transformation. Oliver Wyman helps clients to design, realize and sustain value growth via large-scale transformations.

Lippincott is a creative consultancy specializing in brand and innovation that shapes recognized brands and experiences for clients globally. Lippincott's designers have helped create some of the world's most recognized brands.

NERA Economic Consulting provides economic analysis and advice to public and private entities to achieve practical solutions to highly complex business and legal issues arising from competition, regulation, public policy, strategy, finance and litigation. NERA professionals operate worldwide assisting clients including corporations, governments, law firms, regulatory agencies, trade associations, and international agencies. NERA's specialized practice areas include: antitrust; securities; complex commercial litigation; energy; environmental economics; network industries; intellectual property; product liability and mass torts; and transfer pricing.

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Compensation for Services in Consulting

Oliver Wyman Group is compensated for advice and services primarily through fees paid by clients. Mercer is compensated for advice and services through fees paid by clients, commissions and fees based on assets or members. In the majority of cases, Mercer's Health business is compensated through commissions for the placement of insurance contracts and supplemental compensation from insurers based on such factors as volume, growth of accounts, and total retention of accounts placed by Mercer. Mercer may receive commissions in other parts of its business, such as its Private Client Services business and certain financial advice businesses. Mercer's investments business and certain of Mercer's administration services are compensated typically through fees based on assets under administration or management or fee per member. For a majority of the Mercer-managed investment funds, revenue received from Mercer's investment management clients as sub-advisor fees is reported in accordance with U.S. GAAP, on a gross basis rather than a net basis. For a more detailed discussion of revenue sources and factors affecting revenue in the Consulting segment, refer to Part II, Item 7 ("Management's Discussion and Analysis of Financial Condition and Results of Operations") of this report.

REGULATION

The Company's activities are subject to licensing requirements and extensive regulation under U.S. federal and state laws, as well as laws of other countries in which the Company operates. Across most jurisdictions, we are also subject to various data privacy and data protection laws and regulations that apply to personal information, as well as, in certain jurisdictions, cybersecurity laws and regulations and emerging laws and regulations related to artificial intelligence ("AI"). In addition, we are subject to various financial crime laws and regulations through our activities, activities of associated persons, the products and services we provide and our business and client relationships. Such laws and regulations relate to, among other areas, sanctions and export control, anti-bribery, anti-corruption, anti-money-laundering and counter-terrorist financing. In certain circumstances, we are also required to maintain operating funds primarily related to regulatory requirements outside the U.S. See Part I, Item 1A ("Risk Factors") below for a discussion of how actions by regulatory authorities or changes in legislation and regulation in the jurisdictions in which we operate may have an adverse effect on our businesses and for more information about the laws and regulations related to data privacy, data protection and cybersecurity and the associated risks to our businesses.

Risk and Insurance Services. While laws and regulations vary from location to location, every state of the U.S. and most foreign jurisdictions require insurance market intermediaries and related service providers (such as insurance brokers, agents and consultants, reinsurance brokers and managing general agents) to hold an individual or company license from a government agency or self-regulatory organization. Some jurisdictions issue licenses only to individual residents or locally-owned business entities; in those instances, if the Company has no licensed subsidiary, it may maintain arrangements with residents or business entities licensed to act in such jurisdiction. Such arrangements are subject to an internal review and approval process. Licensing of reinsurance intermediaries is generally less rigorous compared to that of insurance brokers, and most jurisdictions require only corporate reinsurance intermediary licenses.

In the United Kingdom, our business is regulated by the Financial Conduct Authority ("FCA"). The FCA’s responsibilities and powers include licensing of insurance and reinsurance intermediaries and related criteria such as professional competence, financial capacity and the requirement to hold professional indemnity insurance, the broking of premium finance to consumers, and competition powers that enable it to enforce prohibitions on anti-competitive behavior in relation to financial services.

Insurance authorities in the U.S. and certain other jurisdictions in which the Company's subsidiaries do business, including the FCA in the United Kingdom, also have enacted laws and regulations governing the investment of funds, such as premiums and claims proceeds, held in a fiduciary capacity for others. These laws and regulations typically provide for segregation of these fiduciary funds and limit the types of investments that may be made with them, and generally apply to both the insurance and reinsurance business.

Certain of the Company's Risk and Insurance Services activities are governed by other regulatory bodies, such as investment, securities and futures licensing authorities. In the U.S., Marsh and Guy Carpenter use the services of MMC Securities LLC, a SEC registered broker-dealer and introducing broker in the U.S. MMC Securities LLC is a member of the Financial Industry Regulatory Authority ("FINRA"), the National Futures Association and the Securities Investor Protection Corporation ("SIPC"), primarily in connection with capital markets and other investment banking-related services relating to insurance-linked and alternative risk financing transactions. Also in the U.S., Marsh uses the services of MMA Securities LLC, a SEC registered broker-dealer, investment adviser

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and member of FINRA, SIPC and the Municipal Securities Rulemaking Board ("MSRB"), and MMA Asset Management LLC, a SEC registered investment adviser, primarily in connection with retirement, executive compensation and benefits consulting and advisory services to qualified and non-qualified benefits plans, companies and executives and personal wealth management. In the United Kingdom, Marsh and Guy Carpenter use the expertise of MMC Securities Limited, which is authorized and regulated by the FCA to provide advice on securities and investments, including mergers & acquisitions in the United Kingdom. In the European Union, Guy Carpenter uses MMC Securities (Ireland) Limited, which is authorized and regulated by the Central Bank of Ireland to place certain securities and investments in the European Union. MMC Securities LLC, MMC Securities Limited, MMC Securities (Ireland) Limited, MMA Securities LLC, and MMA Asset Management LLC are indirect, wholly-owned subsidiaries of Marsh & McLennan Companies, Inc.

Consulting. Mercer's retirement-related consulting and investment services are subject to pension law and financial regulation in many countries. Depending on the country, Mercer may rely on licensed colleagues or registered legal entities to engage in these services, or may utilize other Marsh McLennan entities or third parties. In addition, trustee services, investment services (including advice to persons, institutions and other entities on the investment of pension assets and assumption of discretionary investment management responsibilities) and retirement and employee benefit program administrative services provided by Mercer and its subsidiaries and affiliates may also be subject to investment and securities regulations in various jurisdictions, including (but not limited to) regulations imposed or enforced by the Securities and Exchange Commission (SEC) and the Department of Labor in the U.S., the FCA in the United Kingdom, the Central Bank of Ireland and the Australian Prudential Regulation Authority and the Australian Securities and Investments Commission. In the U.S., Mercer provides investment services through Mercer Investments LLC, (formerly Mercer Investment Management, Inc.), an SEC-registered investment adviser, which consolidated the activities of each of Mercer’s affiliated investment adviser entities in the U.S. (including Mercer Investment Consulting LLC and Pavilion Advisory Group) in 2019. Mercer Trust Company, a limited purpose New Hampshire chartered trust bank, may also provide services for certain clients of Mercer’s investment management business in the U.S. The benefits insurance consulting and brokerage services provided by Mercer and its subsidiaries and affiliates are subject to the same licensing requirements and regulatory oversight as the insurance market intermediaries described above regarding our Risk and Insurance Services businesses. Depending on the nature of the client and services performed, Mercer may also be subject to direct oversight by the Departments of Health and Human Services and other federal agencies in the U.S. Mercer provides annuity buy-out advice that is subject to regulations (for example, in the U.S., state insurance licensing regulations and ERISA). Mercer uses the services of MMC Securities LLC to provide certain services, including executive benefit and compensation services and securities dealing services.

FATCA. Regulations promulgated by the U.S. Treasury Department pursuant to the Foreign Account Tax Compliance Act and related legislation (FATCA) require the Company to take various measures relating to non-U.S. funds, transactions and accounts. The regulations impose on Mercer and MMA certain client financial account obligations relating to non-U.S. financial institution and insurance clients.

COMPETITIVE CONDITIONS

The Company faces significant competition in all of its businesses from providers of similar products and services, including competition with regard to identifying and pursuing acquisition candidates. The Company also encounters strong competition throughout its businesses from both public corporations and private firms in attracting and retaining qualified employees. As the Company has clients across various geographies, industries and sizes, the competitive landscape is complex and varies across numerous markets. In addition to the discussion below, refer to "Risks Relating to the Company Generally — Competitive Risks," in Part I, Item 1A of this report.

Risk and Insurance Services. The Company's combined insurance and reinsurance services businesses are global in scope. Our insurance and reinsurance businesses compete principally on the sophistication, range, quality and cost of the services and products they offer to clients. The Company encounters strong competition from other insurance and reinsurance brokerage firms that operate on a global, regional, national or local scale in every geography in which it operates, from insurance and reinsurance companies that market, distribute and service their insurance and reinsurance products without the assistance of brokers and from other businesses, including commercial and investment banks, accounting firms, consultants and online platforms, that provide risk-related services and products or alternatives to traditional insurance brokerage services. In addition, third party capital providers have entered the insurance and reinsurance risk transfer market offering products and capital

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directly to the Company’s clients. Their presence in the market increases the competitive pressures that the Company faces.

Certain insureds and groups of insureds have established programs of self-insurance as a supplement or alternative to purchasing traditional third-party insurance, thereby reducing in some cases their need for third-party insurance placements. Certain insureds also obtain coverage directly from insurance providers. There are also many other providers of managing general agents, affinity programs and private client services that compete with the Company's offerings.

Consulting. The Company's consulting businesses face strong competition from other privately and publicly held worldwide and national companies, as well as regional and local firms. These businesses generally compete on the basis of the range, quality and cost of the services and products they provide to clients. Competitors include independent consulting, broking and outsourcing firms, as well as consulting, broking and outsourcing operations affiliated with larger accounting, information systems, technology and financial services firms. Mercer’s Health business faces additional competition from insurers and from non-traditional competitors seeking to enter or expand in the health benefits space (for example, payroll firms, large consumer businesses, and digitally oriented consultancies). Mercer's investments business faces competition from many sources, including investment consulting firms (many of which offer delegated services), investment management firms and other financial institutions. In some cases, clients have the option of handling the services provided by Mercer and Oliver Wyman Group internally, without assistance from outside advisors.

Segmentation of Activity by Type of Service and Geographic Area of Operation.

Financial information relating to the types of services provided by the Company and the geographic areas of its operations is incorporated herein by reference to Note 17, Segment Information, in the notes to the consolidated financial statements included under Part II, Item 8 of this report.

ENVIRONMENTAL, SOCIAL AND GOVERNANCE (ESG))

Since 2008, Marsh McLennan has had a framework for overseeing and managing the company’s approach to environmental sustainability, human capital management and corporate governance. Our ESG Report provides more information about our ESG governance, goals and achievements. It also discloses against aspects of the Task Force on Climate-related Financial Disclosures, Sustainability Accounting Standards Board and Global Reporting Initiative standards and describes the six UN Sustainable Development Goals we have prioritized that most relate to our business. Our ESG Report, Pay Equity Statement, statement on Human Rights and related information is available on our website at marshmclennan.com/about/esg.html. These reports and our website are not deemed part of this report and are not incorporated by reference.

HUMAN CAPITAL

As a professional services firm, we believe the health of our business relies on the strength of our workforce.

For detailed information regarding our human capital management, we encourage investors to visit https://www.marshmclennan.com/about/esg.html for our consolidated ESG Report. The information on this website, and in the ESG report, does not constitute, and should not be viewed as, incorporation by reference of the information contained on, or available through, the website or the report and does not form part of this Form 10-K.

Our People. As of December 31, 2023, the Company and its consolidated subsidiaries employed more than 85,000 colleagues worldwide, including approximately 49,300 in Risk and Insurance Services and 31,300 in Consulting. One-third of our global workforce is located in the U.S. & Canada, with approximately 15% in each of the United Kingdom, Europe and IMEA (India, Middle East, & Africa), with the remainder in Latin America & Caribbean, Asia, and Pacific. Women comprise more than half of our global enterprise workforce, and approximately 33% of our senior leaders are women. In the U.S., where we have the most complete data through workforce self-identification of race and ethnicity, approximately 1 in 4 U.S. colleagues and 18% of U.S. senior leaders identify as non-White.

Our Governance. The Chief People Officer is responsible for developing and executing our enterprise people strategy. This includes the attraction, recruitment, hiring, development and engagement of talent to deliver on our strategy and the design of colleague total rewards programs. The Chief People Officer is also responsible for developing and integrating our inclusion and diversity approach into our strategy, supported by the Chief Diversity & Social Impact Officer.

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Talent & Inclusion. Our Company’s greatest strength is the collective talent of our people. We offer programs globally, regionally and business-specific that are aimed at helping us attract, develop and retain a diverse workforce. We provide resources to support colleagues in learning about diverse experiences, connecting with each other and positively impacting communities. We are committed to helping colleagues perform at their best by encouraging regular discussions about their goals, performance, career aspirations and development opportunities. We offer programming to support their growth and activate a leadership mindset for all colleagues.

We also aim to build a learning culture and deliver a digital-first learning strategy, supplemented by formal programs for key groups. For example, our 2023 Learning Festival offered 31 live sessions in 8 languages with over 18,000 attendees. Top sessions included business briefings with our CEOs, the future of insurance, cyber resilience and AI.

We also recognize the importance of our nearly 18,000 people managers to our talent pipeline and have given them increased support and opportunities for promoting the growth of their teams. In 2023 we offered 450 development workshops with courses covering professional skills, people management and leadership development. Our People Manager Hub is a one-stop digital source for people managers globally. Through the Hub, people managers have access to suggested learning, webinars and resources to support development and provide guidance.

Colleague Engagement. Each year we ask our colleagues to share their views on working at Marsh McLennan through a company-wide engagement survey. Developed internally by our Global Talent Development team, the survey methodology has been consistent since 2011, with updates to specific questions as necessary. In 2023, we expanded the survey with questions on technology and the company's strategy. A third-party administers our survey in order to maintain confidentiality of responses. Collective survey outcomes allow us to monitor the evolution of our culture over time and identify opportunities to build on strengths and address challenges, all with the intention of furthering our productivity through an engaged workforce.

Health and Well-being. As a company, our success depends on the health and well-being of our colleagues. We offer comprehensive health insurance, including medical coverage and other core health benefits based on the market. We also prioritize our colleagues’ mental wellness, including 24/7 access to an Employee Assistance Program for confidential counselling on personal issues for 99% of our colleagues and their eligible family members, and critical incident support in countries where a disaster has occurred. In addition, we offer competitive time-off benefits, including a paid day off each year to volunteer. We support our colleagues as they navigate changing circumstances—milestone life events, health and economic challenges, and new technologies.

Total Rewards. We offer competitive rewards to help build colleagues’ personal wealth and improve their financial well-being. Base pay is one component. Through our annual bonus program, we encourage performance that aligns with the Company’s interests by providing eligible colleagues with discretionary awards. We also offer various incentives in certain circumstances, such as sales incentives and long-term incentives to people in roles that have a significant impact on our long-term performance and success. Our offerings also include retirement benefits, savings and stock investment plans in certain jurisdictions.

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EXECUTIVE OFFICERS OF THE COMPANY

The executive officers and executive officer appointees of the Company are appointed annually by the Company’s Board of Directors. The following individuals are the executive officers of the Company as of February 12, 2024:

Paul Beswick, age 49, is Senior Vice President and Global Chief Information Officer (CIO) of Marsh McLennan. In this role, he manages over 5,000 technologists supporting Marsh McLennan’s global businesses. Prior to his appointment as Marsh McLennan CIO in January 2021, Mr. Beswick was a Partner and Global Head of Oliver Wyman Labs and the Digital Practice at Oliver Wyman. During more than two decades with Oliver Wyman, he worked in various sectors, including retail, transportation, telecom, and consumer goods. Before this, Mr. Beswick headed Oliver Wyman's North American Retail Practice. Mr. Beswick holds an MA (first class) in chemical engineering from Cambridge University.

Katherine J. Brennan, age 45, is Senior Vice President and General Counsel of Marsh McLennan. In this role, she leads Marsh McLennan’s global legal, compliance and public affairs function, which supports the Company’s four businesses, Marsh, Guy Carpenter, Mercer and Oliver Wyman. She also leads the Company’s ESG efforts. Ms. Brennan has held several legal and compliance leadership roles at Marsh McLennan, serving most recently as General Counsel, Marsh LLC. She also served as Deputy General Counsel, Corporate Secretary and Chief Compliance Officer for Marsh McLennan from 2017 to 2021, and prior to that, as General Counsel of Guy Carpenter. Ms. Brennan currently serves on the Board of the Red Cross of Greater New York.

John Q. Doyle, age 60, is President and Chief Executive Officer of Marsh McLennan. Previously, from 2021 to 2022 he served as Group President and Chief Operating Officer, responsible for the strategy and operational objectives of Marsh McLennan’s four global businesses. He joined the firm in 2016 as President of Marsh, then led Marsh as President and CEO from 2017 to 2021. An industry veteran with more than 35 years of management experience, Mr. Doyle began his career at AIG, where he held several executive positions. He is a member of the Board of the New York Police and Fire Widows’ and Children’s Benefit Fund, a Trustee of the Inner-City Scholarship Fund, a member of the Board of Overseers of the Maurice R. Greenberg School of Risk Management, Insurance and Actuarial Science at St. John’s University and a former Director of the American Insurance Association. Mr. Doyle serves as the Chairman of the U.S. Federal Advisory Committee on Insurance.

Martine Ferland, age 62, is Chief Executive Officer of Mercer. She also serves as Vice Chair of Marsh McLennan. Prior to assuming her current role in March 2019, she was Mercer’s Group President, responsible for leading the firm’s regions and Global Business Solutions. She joined Mercer in 2011 as Retirement Business Leader for EMEA, and has served as Europe and Pacific Region President and Co-President, Global Health. Ms. Ferland began her career as a pension actuary and consultant at Willis Towers Watson, where she spent 25 years and held various leadership positions in Montreal and New York. Ms. Ferland is a Fellow of the Society of Actuaries and of the Canadian Institute of Actuaries and a member of the Board of Trustees of the New York Academy of Medicine.

Carmen Fernandez, age 50, is Senior Vice President and Chief People Officer for Marsh McLennan. Prior to her appointment as Chief People Officer in January 2021, Ms. Fernandez held positions within Marsh McLennan for 15 years, most recently Deputy CHRO, CHRO of Guy Carpenter, and HR leadership roles at Mercer, including North America HR Leader, Global HR Leader for the Career business and Chief of Staff in the Office of the CEO. Before joining Marsh McLennan, Ms. Fernandez worked in investment banking at Bank of America and Goldman Sachs. She began her career as a consultant with PricewaterhouseCoopers.

John Jones, age 52, is Chief Marketing and Communications officer of Marsh McLennan. Previously, he served as Chief Marketing and Communications Officer of Marsh from 2018 to 2022. Mr. Jones joined Marsh in 2016 as senior vice president of Marsh’s business planning, leading strategic planning and global growth initiatives. Prior to that, Mr. Jones was senior vice president of commercial marketing and strategy for AIG and has more than 25 years of marketing, communications and strategy experience.

Dean Klisura, age 60, is President and Chief Executive Officer of Guy Carpenter and serves as Vice Chair of Marsh McLennan. Prior to assuming this role in January 2022, he was President of Guy Carpenter, overseeing the North America, International, Specialty and Global Strategic Advisory business units. Prior to joining Guy Carpenter, Mr. Klisura was President of Marsh Global Placement and Advisory Services, leading property and casualty placement activities globally, as well as leading Bowring Marsh, the Insurer Consulting Group, and Marsh Advisory. He joined Marsh in 1993 and held several key global leadership roles including President of Global Specialties.

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Mark McGivney, age 56, is Chief Financial Officer of Marsh McLennan. Prior to assuming this role in January 2016, Mr. McGivney held a number of senior financial management positions since joining the Company in 2007. Most recently he was Senior Vice President, Corporate Finance of Marsh McLennan, and was responsible for leading and directing the Company’s Corporate Development, Treasury and Investor Relations functions from 2014 until 2016. Prior to that, he served as Chief Financial Officer of Marsh, and Chief Financial Officer and Chief Operating Officer of Mercer. His prior experience includes senior positions at The Hanover Insurance Group, including serving as Senior Vice President of Finance, Treasurer, and Chief Financial Officer of the Property & Casualty business, as well as positions with Merrill Lynch and PricewaterhouseCoopers.

Martin South, age 59, is President and Chief Executive Officer of Marsh, a position he assumed in January 2022, and oversees all of Marsh’s businesses and operations globally. He also serves as Vice Chair of Marsh McLennan. With more than 30 years in the insurance industry, Mr. South joined Marsh for the first time in 1985 with Bowring Marsh, a Marsh McLennan broking unit. His industry experience includes senior leadership roles at Zurich Financial Services, where he was a member of the Group Management Board, responsible for all of Zurich’s operations outside of North America and Europe, and CEO of Zurich’s London operations. Since rejoining Marsh in 2007, Mr. South has served as CEO of Marsh’s Asia-Pacific region, CEO of Marsh UK and Ireland, CEO of Marsh Europe and CEO of Marsh U.S. and Canada.

Nicholas Studer, age 50, is Chief Executive Officer of Oliver Wyman Group, a role he assumed in July of 2021. He also serves as Vice Chair of Marsh McLennan. From 2017 to 2021, Mr. Studer was the Managing Partner of the Consumer, Industrial and Services Practice Group, before becoming Managing Partner of Oliver Wyman in 2021. He has held many senior positions at Oliver Wyman including Managing Partner of the Financial Services Practice Group, Head of the European Finance and Risk Practice and Global head of the Corporate and Institutional Banking practice. He has over 25 years of experience consulting in the UK, Continental Europe, and North America.

The Company is subject to the information reporting requirements of the Securities Exchange Act of 1934. In accordance with the Exchange Act, the Company files with, or furnishes to, the SEC its annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and proxy statement for its annual shareholders' meeting. The Company makes these reports and any amendments to these reports available free of charge through its website, www.marshmclennan.com, as soon as reasonably practicable after they are filed with or furnished to the SEC. The SEC also maintains a website at www.sec.gov that contains reports, proxy and information statements and other information regarding issuers, like the Company, that file electronically with the SEC.

The Company also posts on its website certain governance and other information for investors.

The Company encourages investors to visit these websites from time to time, as information is updated and new information is posted. Website references in this report are provided as a convenience and do not constitute, and should not be viewed as, incorporation by reference of the information contained on, or available through, the websites. Therefore, such information should not be considered part of this report.

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Item 1A.    Risk Factors.

You should consider the risks described below in conjunction with the other information presented in this report. These risks have the potential to materially adversely affect the Company's business, results of operations or financial condition.

SUMMARY RISK FACTORS

Some of the factors that could materially and adversely affect our business, financial condition, results of operations or prospects, include the following:

•Our results of operations and investments could be adversely affected by geopolitical or macroeconomic conditions;

•We are subject to significant uninsured exposures arising from errors and omissions, breach of fiduciary duty and other claims;

•We cannot guarantee that we are or will be in compliance with all current and potentially applicable U.S. federal and state or foreign laws and regulations, and actions by regulatory authorities or changes in legislation and regulation in the jurisdictions in which we operate could have a material adverse effect on our business;

•Our business or reputation could be harmed by our reliance on third-party providers or introducers;

•We may not be able to effectively identify and manage actual and apparent conflicts of interest;

•We could incur significant liability or our reputation could be damaged if our information systems are breached or we otherwise fail to protect client or Company data or information systems;

•The costs to comply with, or our failure to comply with, U.S. and foreign laws related to privacy, data security and data protection, such as the EU's General Data Protection Regulation (GDPR) and the California Consumer Privacy Act, as amended by the California Privacy Rights Act, (CCPA), could adversely affect our financial condition, operating results and our reputation;

•Our business performance and growth plans could be negatively affected if we are not able to develop and implement improvements in technology or respond effectively to the threat of digital disruption and other technological change such as AI;

•The loss of members of our senior management team or other key colleagues, or if we are unsuccessful in our efforts to attract, retain and develop talent, could have a material adverse effect on our business;

•Failure to maintain our corporate culture, particularly in a hybrid work environment, could damage our reputation;

•Increasing scrutiny and changing laws and expectations from regulators, investors, clients and our colleagues with respect to our environmental, social and governance (ESG) practices and disclosure may impose additional costs on us or expose us to new or additional risks;

•We face significant competitive pressures in each of our businesses, including from disintermediation, as our competitive landscape continues to evolve;

•We rely on a large number of vendors and other third parties to perform key functions of our business operations and to provide services to our clients. These vendors and third parties may act or fail to act in ways that could harm our business;

•Our inability to successfully recover should we experience a disaster or other business continuity or data recovery problem could cause material financial loss, loss of human capital, regulatory actions, reputational harm or legal liability;

•We face risks when we acquire or dispose of businesses;

•If we are unable to collect our receivables, our results of operations and cash flows could be adversely affected;

•We may not be able to obtain sufficient financing on favorable terms;

•Our defined benefit pension plan obligations could cause the Company's financial position, earnings and cash flows to fluctuate;

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•Our significant non-U.S. operations expose us to exchange rate fluctuations and various risks that could impact our business;

•Our quarterly revenues and profitability may fluctuate significantly;

•Credit rating downgrades would increase our financing costs and could subject us to operational risk;

•Our current debt level could adversely affect our financial flexibility;

•The current U.S. tax regime has provisions which have unintended consequences and may also impact our tax rate in varying degrees based on where our global income is earned;

•We are exposed to multiple risks associated with the global nature of our operations;

•Results in our Risk and Insurance Services segment may be adversely affected by a general decline in economic activity;

•Volatility or declines in premiums and other market trends may significantly impede our ability to grow revenues and profitability;

•Adverse legal developments and future regulations concerning how intermediaries are compensated by insurers or clients, as well as allegations of anti-competitive behavior or conflicts of interest, could have a material adverse effect on Marsh’s business, results of operations and financial condition;

•Mercer’s Wealth business is subject to a number of risks, including risks related to public and private capital market fluctuations, third-party asset managers and custodians, operations and technology risks, conflicts of interest, ESG and greenwashing, asset performance and regulatory compliance, that, if realized, could result in significant damage to our business;

•Revenues for the services provided by our Consulting segment may decline for various reasons, including as a result of changes in economic conditions, the value of equity, debt and other asset classes, our clients’ or an industry's financial condition or government regulation or an accelerated trend away from actively managed investments to passively managed investments;

•Factors affecting defined benefit pension plans and the services we provide relating to those plans could adversely affect Mercer; and

•The profitability of our Consulting segment may decline if we are unable to achieve or maintain adequate utilization and pricing rates for our consultants.

RISKS RELATING TO THE COMPANY GENERALLY

Macroeconomic Risks

Our results of operations and investments could be adversely affected by geopolitical or macroeconomic conditions.

Geopolitical and macroeconomic conditions, including from multiple major wars, escalating conflict throughout the Middle East and rising tension in the South China Sea, slower GDP growth or recession, lower interest rates, capital markets volatility and inflation affect our clients' businesses and the markets they serve. These conditions, including inflationary expense pressure with our clients, may reduce demand for our services or depress pricing for those services, which could have a material adverse effect on our results of operations.

For example, the war in Ukraine and the escalating conflict throughout the Middle East have resulted in worldwide geopolitical and macroeconomic uncertainty and may negatively impact other regional and global economic markets (including Europe, the Middle East and the U.S.), companies in other countries (particularly those that have done business with Russia or have substantial exposure to, or operations in, impacted countries) and various sectors, industries and markets for securities and commodities globally, such as oil and natural gas, and may increase financial market volatility and adversely impact regional and global economic markets, industries and companies. Moreover, the COVID-19 pandemic impacted businesses, including our clients, third-party vendors and business partners, globally in every geography in which we operate. In addition, the potentially divergent laws and regulations as a result of Brexit may continue to lead to economic and legal uncertainty, causing increased economic volatility or disrupting the markets and clients we serve.

Changes in macroeconomic and geopolitical conditions could also shift demand to services for which we do not have a competitive advantage, and this could negatively affect the amount of business that we are able to obtain.

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More generally, our investments, including our minority investments in other companies as well as our cash investments and those held in a fiduciary capacity, are subject to general credit, liquidity, counterparty, foreign exchange, market and interest rate risks. For example, fluctuations in interest rates and foreign exchange rates between the U.S. dollar and foreign currencies may adversely affect our results of operations. Lower interest rates may lead to a decline in our fiduciary income.

These risks may be exacerbated by global macroeconomic conditions, market volatility and regulatory, financial and other difficulties affecting the companies in which we have invested or that may be faced by financial institution counterparties. During times of stress in the banking industry, counterparty risk can quickly escalate, potentially resulting in substantial trading and investment losses for corporate and other investors. In addition, we may incur investment losses as a result of unusual and unpredictable market developments, and we may experience lower earnings if the yields on investments begin to decline. If the banking system or the fixed income, interest rate, credit or equity markets deteriorate, the value and liquidity of our investments could be adversely affected. Finally, the value of the Company's assets held in other jurisdictions, including cash holdings, may decline due to foreign exchange fluctuations.

Legal and Regulatory Risks

We are subject to significant uninsured exposures arising from errors and omissions, breach of fiduciary duty and other claims.

Our businesses provide numerous professional services, including the placement of insurance and the provision of consulting, investment advisory, investment management and actuarial services, to clients around the world. As a result, the Company and its subsidiaries are subject to a significant number of errors and omissions, breach of fiduciary duty, breach of contract and similar claims, which we refer to collectively as "E&O claims." In our Risk and Insurance Services segment, such claims include allegations of damages arising from our failure to assess clients’ risks, advise clients, place coverage, or notify insurers of potential claims on behalf of clients in accordance with our obligations to them. For example, these claims could include allegations related to losses from cyberattacks associated with policies where cyber risk was not specifically included or excluded in policies, commonly referred to as “silent cyber.” In our Consulting segment, where we increasingly act in a fiduciary capacity through our investments business, such claims could include allegations of damages arising from the provision of consulting, investment management (including, for example, from trading or other operational errors), actuarial, pension administration and other services. We may also be exposed to claims related to services or solutions offered by the Consulting segment in addition to consulting services. These Consulting segment services frequently involve complex calculations and services, including (i) making assumptions about, and preparing estimates concerning, contingent future events, (ii) drafting and interpreting complex documentation governing pension plans, (iii) calculating benefits within complex pension structures, (iv) providing individual financial planning advice including investment advice and advice relating to cashing out of defined benefit pension plans, (v) providing investment advice, including guidance on asset allocation and investment strategy, and (vi) managing client assets, including the selection of investment managers and implementation of the client’s investment policy. We provide these services to a broad client base, including clients in the public sector. Matters may relate to services provided by the Company dating back many years. Such claims may subject us to significant liability for monetary damages, including punitive and treble damages, negative publicity and reputational harm, and may divert personnel and management resources. We may be unable to effectively limit our potential liability in certain jurisdictions, including through insurance, or in connection with certain types of claims, particularly those concerning claims of a breach of fiduciary duty.

In establishing liabilities for E&O claims in accordance with U.S. generally accepted accounting principles ("U.S. GAAP"), the Company uses case level reviews by inside and outside counsel, actuarial analysis by Oliver Wyman, a subsidiary of the Company, and other methods to estimate potential losses. A liability is established when a loss is both probable and reasonably estimable. The liability is assessed quarterly and adjusted as developments warrant. In many cases, the Company has not recorded a liability, other than for legal fees to defend a claim, because we are unable, at the present time, to make a determination that a loss is both probable and reasonably estimable. Given the judgment involved in estimating and establishing such liabilities, as well as the unpredictability of E&O claims and the litigation that can flow from them, it is possible that an adverse outcome in a particular matter could have a material adverse effect on the Company's business, results of operations or financial condition.

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We cannot guarantee that we are or will be in compliance with all current and potentially applicable U.S. federal and state or foreign laws and regulations, and actions by regulatory authorities or changes in legislation and regulation in the jurisdictions in which we operate could have a material adverse effect on our business.

Our activities are subject to extensive regulation under the laws of the U.S. and its various states, the United Kingdom, the European Union and its member states, Australia and the other jurisdictions in which we operate. We are also subject to trade sanctions laws relating to countries such as Afghanistan, Belarus, Cuba, Iran, North Korea, Russia, Syria, Ukraine (Russia-controlled territories) and Venezuela, and anti-corruption laws such as the U.S. Foreign Corrupt Practices Act and the U.K. Bribery Act. We are subject to numerous other laws on matters as diverse as internal control over financial reporting and disclosure controls and procedures, securities regulation, data privacy and protection, cybersecurity, taxation, anti-trust and competition, immigration, wage-and-hour standards and employment and labor relations.

The U.S. and foreign laws and regulations that apply to our operations are complex and may change rapidly, and our efforts to comply and keep up with them require significant resources. In some cases, these laws and regulations may decrease the need for our services, increase our costs, negatively impact our revenues or impose operational limitations on our business, including on the products and services we may offer or on the amount or type of compensation we may collect. In addition, the financial and operational impact of complying with laws and regulations has increased in the current environment of increased regulatory activity and enforcement. Changes with respect to the applicable laws and regulations may impose additional and unforeseen costs on us or pose new or previously immaterial risks to us. There can be no assurance that current and future government regulations will not adversely affect our business, and we cannot predict new regulatory priorities, the form, content or timing of regulatory actions, and their impact on our business and operations. In addition, geopolitical conflict, such as the war in Ukraine and the escalating conflict throughout the Middle East, has resulted in, and may continue to result in, new and rapidly evolving trade sanctions, which may increase our costs, negatively impact our revenues or impose additional operational limitations on our businesses.

While we attempt to comply with applicable laws and regulations, there can be no assurance that we, our employees, our consultants and our contractors and other agents are in full compliance with such laws and regulations or interpretations at all times, or that we will be able to comply with any future laws or regulations. If we fail to comply or are accused of failing to comply with applicable laws and regulations, including those referred to above, or new and evolving regulations regarding cybersecurity, AI or environmental, social and governance matters, we may become subject to investigations, criminal penalties, civil remedies or other consequences, including fines, injunctions, loss of an operating license or approval, increased scrutiny or oversight by regulatory authorities, the suspension of individual employees, limitations on engaging in a particular business or redress to clients or other parties, and we may become exposed to negative publicity or reputational damage. Moreover, our failure to comply with laws or regulations in one jurisdiction may result in increased regulatory scrutiny by other regulatory agencies in that jurisdiction or regulatory agencies in other jurisdictions. These inquiries consume significant management attention, and the cost of compliance and the consequences of failing to be in compliance could therefore have a material adverse effect on our business.

In most jurisdictions, government regulatory authorities have the power to interpret and amend or repeal applicable laws and regulations, and have discretion to grant, renew and revoke the various licenses and approvals we need to conduct our activities. Such authorities may require the Company to incur substantial costs in order to comply with such laws and regulations. In some areas of our businesses, we act on the basis of our own or the industry's interpretations of applicable laws or regulations, which may conflict from state to state or country to country. In the event those interpretations eventually prove different from the interpretations of regulatory authorities, we may be penalized or precluded from carrying on our previous activities. Moreover, the laws and regulations to which we are subject may conflict among the various jurisdictions and countries in which we operate, which increases the likelihood of our businesses being non-compliant in one or more jurisdictions.

In addition, we may be responsible for the legal and regulatory liabilities of companies that we acquire.

Additional information regarding certain ongoing investigations and certain other legal and regulatory proceedings is set forth in Note 16, Claims, Lawsuits and Other Contingencies, in the notes to the consolidated financial statements included under Part II, Item 8 of this report.

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Our business or reputation could be harmed by our reliance on third-party providers or introducers.

We currently utilize the services of hundreds of third-party providers to meet the needs of our clients around the world.

There is a risk that our third-party providers or introducers engage in business practices that are prohibited by our internal policies or violate applicable laws and regulations, such as the U.S. Foreign Corrupt Practices Act and the U.K. Anti-Bribery Act.

We may not be able to effectively identify and manage actual and apparent conflicts of interest.

Given the significant volume of our engagements, potential conflicts of interest may arise across our businesses. There is a risk that we may not effectively identify and manage potential conflicts of interest, including but not limited to where our services to a client conflict, or are perceived to conflict, with the interests of another client or our own interests, where we receive revenue or benefits from third-parties with whom we conduct business (including but not limited to insurers, investment managers and vendors) and where our colleagues have personal interests.

Cybersecurity, Data Protection and Technology Risks

We could incur significant liability or our reputation could be damaged if our information systems are breached or we otherwise fail to protect client or Company data or information systems.

In operating our business and providing services and solutions to clients, we collect, use, store, transmit and otherwise process certain electronic information, including personal, confidential, proprietary and sensitive data such as financial records, health care, mergers and acquisitions and personal data of our clients, colleagues and vendors. We rely on the efficient, uninterrupted and secure operation of complex information technology systems and networks to operate our business and securely process, transmit and store electronic information. In the normal course of business, we also share electronic information with our vendors and other third parties. This electronic information comprises sensitive and confidential data, including information related to financial records, health care, mergers and acquisitions and clients’ personal data. Our information technology systems and information security control systems, and those of our numerous third-party providers, as well as the control systems of critical infrastructure they rely on, such as power grids, and undersea cables, are potentially vulnerable to unauthorized access, damage or interruption from a variety of external threats, including software bugs, physical attack, cyberattacks, computer viruses and other malware, malicious or destructive code, ransomware, social engineering attacks (including phising and digital or telephonic impersonation), hacking, denial-of-service attacks and other types of data and systems-related modes of attack. The techniques used to achieve such unauthorized access, damage or interruption change frequently and new techniques may not be identified until they are launched against a target, and we may be unable to anticipate these techniques or implement adequate preventative or remedial measures, resulting in potential data loss, data unavailability, data corruption or other damage to information technology systems. In addition, remote and hybrid work arrangements have increased the risk of phishing and other cybersecurity attacks, unauthorized dissemination of personal, confidential, proprietary or sensitive data, and unauthorized access to company computing assets. Further, a disruption of physical infrastructure could impact our ability to conduct business and service clients. This may include deliberate or unintentional disruption of service to electrical systems, satellite communications, undersea or terrestrial cable systems, Internet services, or other systems our colleagues or third parties rely on us to conduct business in a multitude of jurisdictions across the globe. Disruptions may be the result of weather, natural disaster, war, terrorism, pandemic, or other natural or geopolitical events. Our systems are also subject to compromise from internal threats such as fraud, mistake, misconduct or other improper action by employees, vendors and other third parties with otherwise legitimate access to our systems. Moreover, we face the ongoing challenge of managing access controls in a complex environment. The latency of a compromise is often measured in months but could be years, and we may not be able to detect a compromise in a timely manner, and even if detected, there can be no assurance that we can mitigate or remediate such compromise in an adequate or timely manner. We could experience significant financial and reputational harm if our information systems are breached, sensitive client or Company data are compromised, surreptitiously modified, rendered inaccessible for any period of time or maliciously made public, or if we fail to make adequate or timely disclosures to the public, law enforcement agencies or regulators following any such event, whether due to delayed discovery or a failure to follow existing protocols.

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Cyberattacks are increasing in frequency and evolving in nature. We are at risk of attack by a variety of adversaries, including nation states, state-sponsored organizations, organized crime and hackers, through use of increasingly sophisticated methods of attack, including the deployment of AI to find and exploit vulnerabilities, "deep fakes", long-term, persistent attacks (referred to as advanced persistent threats) and the use of the IT supply chain to introduce malware through software updates or compromised suppliers accounts or hardware. In particular, the advance of AI and large language models has given rise to additional vulnerabilities and potential entry points for cyber threats. With generative AI tools, threat actors may have additional tools to automate breaches or persistent attacks, evade detection, or generate sophisticated phishing emails or other forms of digital impersonation. In addition, increasing use of generative AI models in our internal systems may create new attack methods for adversaries. Because generative AI is a new field, understanding of cybersecurity risks and protection methods continues to develop, and features that rely on generative AI, including in services provided to us by third parties, may be susceptible to unanticipated cybersecurity threats from sophisticated adversaries and other cybersecurity incidents. Further, we are at increased risk of a cyberattack during periods of heightened geopolitical conflict, such as the war in Ukraine and the escalating conflict throughout the Middle East, as diplomatic events and economic policies may trigger espionage or retaliatory cyber incidents. Despite our efforts to comply with applicable cybersecurity requirements and mitigate risks of cybersecurity threats, we cannot be certain that our security measures will definitively prevent, contain, detect, or remediate all cybersecurity threats or incidents or other instructions from malware currently in existence or developed in the future.

As the breadth and complexity of the technologies we use and the software and platforms we develop continue to grow, including as a result of the use of mobile devices, cloud services, "open source" software, social media tools and the increased reliance on devices connected to the Internet (known as the "Internet of Things"), the potential risk of security breaches and cyber-attacks also increases. Despite ongoing efforts to improve our ability to protect data from compromise, we may not be able to protect all of our data across our diverse systems. Our efforts to improve and protect data from compromise may also identify previously undiscovered instances of security breaches or other cyber incidents. Our policies, employee training (including phishing prevention training), procedures and technical safeguards may also be insufficient to prevent, detect or remediate improper access to confidential, personal or proprietary information. In addition, the competition for talent in the data privacy and cybersecurity space is intense, and we may also be unable to hire, develop or retain suitable talent capable of adequately detecting, mitigating or remediating these risks.

Should an attacker gain access to our network using compromised credentials of an authorized user, we are at risk that the attacker might successfully leverage that access to compromise additional systems and data. Certain measures that could increase the security of our systems, such as data encryption (including encryption of data at rest), heightened monitoring and logging, scanning for source code errors or deployment of multi-factor authentication, take significant time and resources to deploy broadly, and such measures may not be deployed in a timely manner or be effective against an attack. The inability to implement, maintain and upgrade adequate safeguards could have a material adverse effect on our business.

Our information systems must be continually updated, patched, and upgraded to protect against known vulnerabilities. The volume of new software vulnerabilities has increased markedly, as has the criticality of patches and other mitigation and remedial measures. In addition to mitigating and remediating newly identified vulnerabilities, previously identified vulnerabilities must also be continuously addressed. Accordingly, we are at risk that cyberattackers exploit these known vulnerabilities before they have been communicated by vendors or addressed. Due to the large number and age of the systems and platforms that we operate, the increased frequency at which vendors are issuing security patches to their products, the need to test patches and, in some cases coordinate with clients and vendors, before they can be deployed, we perpetually face the substantial risk that we cannot deploy patches in a timely manner. We are also dependent on third party vendors to keep their systems patched and secure in order to protect our data. Any failure related to these activities could have a material adverse effect on our business.

We have numerous vendors and other third parties who receive personal information from us in connection with the services we offer our clients and our employees. We also use hundreds of IT vendors and software providers to maintain and secure our global information systems infrastructure. In addition, we have migrated certain data, and may increasingly migrate data, to the cloud where it is hosted by third-party providers. Some of these vendors and third parties also have direct access to our systems or data. We are at risk of a cyberattack involving a vendor or other third party, which could result in a breakdown of such third party’s data protection processes or the cyberattackers gaining access to our infrastructure or data through a supply chain attack. Highly publicized data

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security breaches, such as the October 2023 attack on Okta may embolden malicious actors to target the IT supply chain and providers of business software. Our control over and ability to monitor the cybersecurity practices of our third-party vendors and service providers, and other third parties with whom we do business, remains limited, and there can be no assurance that we can prevent, mitigate, or remediate the risk of any compromise or failure in the cybersecurity infrastructure owned or controlled by such third parties. Additionally, any contractual protections with such third parties, including our right to indemnification, if any, may be limited or insufficient to prevent a negative impact on our business from such compromise or failure.

We have a history of making acquisitions and investments. The process of integrating the information systems of any businesses we acquire is complex and exposes us to additional risk. For instance, we may not adequately identify weaknesses and vulnerabilities in an acquired entity’s information systems, either before or after the acquisition, which could affect the value we are able to derive from the acquisition, expose us to unexpected liabilities or make our own systems more vulnerable to a cyberattack. In addition, if we discover a historical compromise, security breach or other cyber incident related to the target’s information systems following the close of the acquisition, we may be liable and exposed to significant costs and other unforeseen liabilities. We may also be unable to integrate the systems of the businesses we acquire into our environment in a timely manner, which could further increase these risks until such integration takes place.

We have experienced data incidents and cybersecurity breaches, such as malware incursions (including computer viruses and ransomware), vulnerabilities in the software on which we rely, users exceeding their data access authorization, employee misconduct and incidents resulting from human error, such as emails sent to the wrong recipient, loss of portable and other data storage devices or misconfiguration of software or hardware resulting in inadvertent exposure of personal, sensitive, confidential or proprietary information. In April 2021, an unauthorized actor leveraged a vulnerability in a third party's software and gained access to a limited set of data in our environment. Like many companies, we are also subject to social engineering attacks such as WhatsApp scams and regular phishing email campaigns directed at our employees that can result in malware infections, fraud and data loss. Although these incidents have resulted in data loss and other damages, to date, they have not had a material adverse effect on our business or operations. In the future, these types of incidents could result in personal, sensitive, confidential or proprietary information, including client, employee or Company data, being lost or stolen, surreptitiously modified, rendered inaccessible for any period of time, or maliciously made public, which could have a material adverse effect on our business. In the event of a cyberattack, we might have to take our systems offline, which could interfere with services to our clients or damage our reputation. A cyberattack may also result in systems or data being encrypted or otherwise unavailable due to ransomware or other malware. We also may be unable to detect an incident, assess its severity or impact, or appropriately respond in a timely or adequate manner. In addition, our liability insurance, which includes cyber insurance, may not be sufficient in type or amount to cover us against claims related to security breaches, cyberattacks and other related data and system incidents. Further, we cannot be sure that our existing coverage will continue to be available on acceptable terms or at all or that our insurers will not deny coverage as to any future claim.

The costs to comply with, or our failure to comply with, U.S. and foreign laws related to privacy, data security and data protection, such as the EU's General Data Protection Regulation (GDPR) and the California Consumer Privacy Act, as amended by the California Privacy Rights Act, (CCPA), could adversely affect our financial condition, operating results and our reputation.

Improper collection, use, disclosure, cross border transfer, retention and other processing of confidential, personal, or proprietary data could result in regulatory scrutiny, legal and financial liability, or harm to our reputation. In operating our business and providing services and solutions to clients, we store and transfer sensitive employee and client data, including personal data, in and across multiple jurisdictions. We collect data from client and individuals located all over the world and leverage systems and teams to process it. As a result, we are subject to a variety of laws and regulations in the U.S., Europe and around the world regarding privacy, data protection, data security and cyber security. These laws and regulations are continuously evolving and developing. Some of these laws and regulations are increasing the level of data handling restrictions, including rules on data localization, all of which could affect our operations and result in regulatory liability and high fines. In particular, high-profile data breaches at major companies continue to be disclosed regularly, which is leading to even greater regulatory scrutiny and fines at the highest levels they have ever been. These fines are not limited to data breaches and regulators are increasingly focusing on other data processing activities including those related to ad-tech and “data subject” rights. The number of laws that apply to us keeps increasing and the interpretation of such laws is often uncertain and may be conflicting.

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At the international level, we are subject to an increasing number of comprehensive privacy laws including, for example, those passed in Indonesia, the Kingdom of Saudi Arabia and India. Many of these laws, which are modeled after the GDPR, have greatly increased the jurisdictional reach of privacy laws and added a broad array of requirements for handling personal data, such as the public disclosure of data breaches, data protection impact assessments, data portability and the appointment of data protection officers in some cases. Following the UK’s withdrawal from the EU, we are also subject to the UK General Data Protection Regulation (“UK GDPR”), a version of the GDPR as implemented into UK law, and this law may not mirror the GDPR, thereby adding operational complexity and legal risk. Given the breadth and depth of changes in data protection obligations, including classifying data and committing to a range of administrative, technical and physical controls to protect data and enable data transfers across borders, our compliance with such laws will continue to require time, resources and review of the technology and systems we use. Despite a proliferation of regulatory guidance papers, there remains uncertainty in key areas related to these laws, and that uncertainty could result in potential liability for our failure to meet our obligations, including the possibility of significant fines some of which can amount to 4% or more of our global revenue. Further, despite recent developments, including a new U.S.- EU Data Privacy Framework and the U.S.-UK Data Bridge, there remains a high level of uncertainty concerning the future of the flow of personal information between the U.S. and EU, between the U.S. and the UK and between the UK and the EU, and that uncertainty may impair our ability to offer our existing and planned products and services or increase our cost of doing business. Some of the global laws enacted in recent years, including those in China and the Kingdom of Saudi Arabia, also include data localization elements that will require that certain personal data stay within their borders. These requirements are complex and our efforts to comply with them require significant resources, and we cannot guarantee we are or will be in full compliance with such laws at all times.

At the U.S. federal level, we are subject to various privacy laws and regulations, including those promulgated under the authority of the U.S. Federal Trade Commission, which has the authority to regulate and enforce against unfair or deceptive acts or practices in or affecting commerce, including with respect to data privacy and cybersecurity. At the U.S. state level, we are subject to laws and regulations related to privacy, such as the CCPA which introduced concepts such as transparency and rights like access and deletion, that have been enacted by over a dozen states with many more on the verge of enacting such laws. These laws establish a privacy framework for covered businesses, including various obligations imposed on them related to the personal information they collect and use, and offer various rights for their state residents. Some of these laws provide a private right of action for violations and in some cases damages may be significant. Many of these laws diverge from the CCPA and create their own set of rules and this proliferation of inconsistent state level privacy laws will add operational complexity and increased risk of noncompliance or violations which could trigger enforcement action or litigation.

In addition to data protection and data privacy laws, foreign countries and U.S. states are enacting AI and cybersecurity laws and regulations. For example, in late 2023 the New York State Department of Financial Services (NYDFS) issued amendments to its previous cybersecurity regulations which imposed obligations on companies such as Marsh McLennan, including for example, requiring companies to provide evidence of how they are implementing their data retention, data governance and data classifications policies and procedures. A number of states have also adopted laws covering data collected by insurance licensees that include security and breach notification requirements. All of these evolving compliance and operational requirements impose significant costs that are likely to increase over time, may divert resources from other initiatives and projects and could restrict the way services involving data are offered, all of which may adversely affect our results of operations.

Many statutory requirements, both in the U.S. and abroad, include obligations for companies to notify individuals of security breaches involving certain personal information, which could result from breaches experienced by us or our vendors. For example, laws in all 50 U.S. states generally require businesses to provide notice under certain circumstances to consumers whose personal information has been disclosed as a result of a breach. In addition to government regulation, our agreements with certain third parties may require us to notify them in the event of a security breach. Further, privacy advocates and industry groups have and may in the future propose self-regulatory standards. These laws, rules and industry standards may legally or contractually apply to us, or we may elect to comply with them. We expect that there will continue to be new proposed laws and regulations concerning data privacy and security, and we cannot yet determine the impact such future laws, regulations and standards may have on our business. Many of these laws and rules also include strict notification requirements for organizations related to confirmed or suspected breaches. This narrow notification window is often too short to

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fully validate the facts, and there is an increased risk of reporting a false alarm or immaterial breach, which may lead to reputational damage despite there not being an actual data breach.

We post public privacy policies and other documentation regarding our collection, use, disclosure, cross-border transfer, retention, and other processing of personal information. Although we endeavor to comply with our published policies and other documentation, we may at times fail to do so or may be perceived to have failed to do so. Moreover, despite our efforts, we may not be successful in achieving compliance if our employees, contractors, service providers, vendors or other third parties with whom we do business fail to comply with our published policies and documentation. Such failures could carry similar consequences or subject us to potential enforcement actions or investigations if they are found to be deceptive, unfair or misrepresentative of our actual practices.

Furthermore, enforcement actions and investigations by regulatory authorities related to data security incidents and privacy violations, including an ongoing focus on compliance related to website "cookies" and other online trackers, as well as the use of online session recording tools in some countries or U.S. states, continue to increase. Privacy violations, including unauthorized use disclosure or transfer of sensitive, personal or confidential client or Company data, whether through systems failure, employee negligence, fraud or misappropriation, by the Company, our vendors or other parties with whom we do business (if they fail to meet the standards we impose) could damage our reputation and subject us to significant litigation, monetary damages, regulatory enforcement actions, fines and criminal prosecution in one or more jurisdictions. Given the complexity of operationalizing the various privacy laws mentioned above, the maturity level of proposed compliance frameworks and the continued lack of certainty on how to implement their requirements, we and our clients are at risk of enforcement actions taken by data protection authorities around the world or litigation from consumer advocacy groups acting on behalf of data subjects. We may not be able to respond quickly or effectively to regulatory, legislative and other developments, and these changes may in turn impair our ability to offer our existing or planned products and services and increase our cost of doing business.

Our business performance and growth plans could be negatively affected if we are not able to develop and implement improvements in technology or respond effectively to the threat of digital disruption and other technological change such as AI.

We depend in large part on our technology systems for conducting business, as well as for providing the data and analytics we use to manage our business. As a result, our business success is dependent on maintaining the effectiveness of existing technology systems and on continuing to develop and enhance technology systems that support our business processes and strategic initiatives in a cost and resource efficient manner, particularly as our business processes become more digital. We have a number of strategic initiatives involving investments in or partnerships with technology companies as part of our growth strategy, as well as investments in technology, including generative AI, and infrastructure to support our own systems.

These investments may be costly and require significant capital expenditures, may not be profitable or may be less profitable than what we have experienced historically. In addition, investments in technology systems may not deliver the benefits or perform as expected, or may be replaced or become obsolete more quickly than expected, which could result in operational difficulties or additional costs. In some cases, we also depend on key vendors and partners to provide technology and other support for our strategic initiatives. If these vendors or partners fail to perform their obligations or otherwise cease to work with us, our ability to execute on our strategic initiatives could be adversely affected. If we do not keep up with technological changes or execute effectively on our strategic initiatives, our business and results of operations could be adversely impacted.

In addition, to remain competitive in many of our business areas, we must anticipate and respond effectively to the threat of digital disruption and other technological change such as generative AI. The threat comes from traditional players, such as insurers, through disintermediation as well as from new entrants, such as technology companies, "Insurtech" start-up companies and others. In the past few years, there has been a substantial increase in private equity investments into these Insurtech companies. These players are focused on using technology and innovation, including AI, digital platforms, data analytics, robotics and blockchain, to simplify and improve the client experience, increase efficiencies, alter business models and effect other potentially disruptive changes in the industries in which we operate.

We are actively investing in generative AI tools. While our internal generative AI tool, LenAI, was designed to meet our standards for data security and to address and mitigate the risks associated with this new technology, our use of generative AI in certain products and services may present risks and challenges that remain uncertain due to

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the relative novelty of this technology. These risks may include enhanced governmental or regulatory scrutiny, litigation or ethical concerns. While we are implementing certain mitigation measures and governance to the proliferation of AI tools, these measures may be inadequate or may not meet a growing number of legal and regulatory requirements related to AI.

Competitive Risks

The loss of members of our senior management team or other key colleagues, or if we are unsuccessful in our efforts to attract, retain and develop talent, could have a material adverse effect on our business.

We rely upon the contributions of our senior management team to establish and implement our business strategy and to manage the future growth of our business. We may be unable to retain them, particularly if we do not offer employment terms that are competitive with the rest of the labor market. The loss of any of the senior management team could limit our ability to successfully execute our business strategy or adversely affect our ability to retain existing and attract new clients. Moreover, we could be adversely affected if we fail to adequately plan for the succession of members of our senior management team or if our succession plans do not operate effectively.

Across all of our businesses, our colleagues are critical to developing and retaining client relationships as well as performing the services on which our revenues are earned. It is therefore important for us to attract, incentivize and retain significant revenue-producing employees and the key managerial and other professionals who support them. We face numerous challenges in this regard, including the intense competition for talent, which has accelerated in recent years. Such challenges include the increased mobility of colleagues in light of more flexible working models, market dislocation resulting from proposed and actual combinations in the industry, raids by competitors, and fostering an inclusive and diverse workplace.

Losing colleagues who manage or support substantial client relationships or possess substantial experience or expertise could adversely affect our ability to secure and complete client engagements, which could adversely affect our results of operations. If a key employee were to join an existing competitor or form a competing company, some of our clients could choose to use the services of that competitor instead of our services. If a colleague joins us from a competitor and is subject to enforceable restrictive covenants, we may not be able to secure client engagements or maximize the colleague's potential. In addition, regulation or legislation impacting the workforce, such as the proposed U.S. Federal Trade Commission rule regarding noncompete clauses, may lead to increased uncertainty and competition for talent.

Failure to maintain our corporate culture, particularly in a hybrid work environment, could damage our reputation.

We strive to foster a culture in which our colleagues act with integrity and feel comfortable speaking up about potential misconduct. We are a people business, and our ability to attract and retain colleagues and clients is dependent upon our commitment to an inclusive and diverse workplace, trustworthiness, ethical business practices and other qualities. Our colleagues are the cornerstone of this culture, and acts of misconduct by any colleague, and particularly by senior management, could erode trust and confidence and damage our reputation among existing and potential clients and other stakeholders. Remote and hybrid work arrangements, particularly following the COVID-19 pandemic, may also negatively impact our ability to maintain and promote our culture, as we believe being together is integral to promoting our culture.

Increasing scrutiny and changing laws and expectations from regulators, investors, clients and our colleagues with respect to our environmental, social and governance (ESG) practices and disclosure may impose additional costs on us or expose us to new or additional risks.

There is increased focus, including from governmental organizations, regulators (including the SEC in the U.S.), investors, colleagues and clients, on ESG issues such as environmental stewardship, climate change, greenhouse gas emissions, inclusion and diversity, human rights, racial justice, pay equity, workplace conduct, cybersecurity and data privacy. Negative public perception, adverse publicity or negative comments in social media could damage our reputation if we do not, or are not perceived to, adequately address these issues. Any harm to our reputation could impact colleague engagement and retention and the willingness of clients and our partners to do business with us.

Additionally, there has been increased regulatory focus on ESG and sustainability. For example, laws and regulations related to ESG issues continue to evolve, including in the U.S., the U.K., the EU and Australia, and these regulations may impose additional compliance or disclosure obligations on us. In particular, heightened

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demand for, and scrutiny of, ESG and sustainable-related products, funds, investment strategies and advice has increased the risk that we could be perceived as, or accused of, making inaccurate or misleading statements, commonly referred to as "greenwashing" or that we have otherwise run afoul of regulation. Such perceptions or accusations could damage our reputation, result in litigation or regulatory enforcement actions, and adversely affect our business. Furthermore, perceptions of our efforts to achieve ESG goals or advance ESG and sustainable-related products, funds, investment strategies or advice may differ widely among stakeholders and could present risks to our reputation and business, including litigation risk. For example, in the U.S. there has been increased legal scrutiny on inclusion and diversity-related programs and initiatives.

Moreover, as ESG reporting standards continue to evolve, including with guidance from the International Sustainability Standards Board (ISSB) and the European Sustainability Reporting Standards (ESRS) under the Corporate Sustainability Reporting Directive (CSRD), we continue to evaluate and update our public disclosures in these areas, including refining our disclosure of metrics and goals in accordance with the guidance and our own ESG assessments and priorities. These disclosures, metrics and goals and any failure to accurately report or comply with federal, state or international ESG laws and regulations, or to achieve progress on our metrics and goals on a timely basis, or at all, may result in legal and regulatory proceedings against us and negatively impact our reputation.

Implementation of our ESG initiatives also depends in part on third-party performance or data that is outside the Company's control.

In addition, organizations that provide information to investors on corporate governance and related matters have developed ratings processes for evaluating companies on their approach to ESG matters, and unfavorable ratings of our company or our industries may lead to negative investor sentiment and the diversion of investment to other companies or industries, exclusion of our stock from ESG-oriented indices or investment funds or harm our relationships with regulators and the communities in which we operate.

We face significant competitive pressures in each of our businesses, including from disintermediation, as our competitive landscape continues to evolve.

As a global professional services firm, the Company faces competition in each of its businesses, and the competitive landscape continues to change and evolve. Our ability to compete successfully depends on a variety of factors, including the quality and expertise of our colleagues, our geographic reach, the sophistication and quality of our services, our pricing relative to competitors, our clients’ ability to self-insure or use internal resources instead of consultants, and our ability to respond to changes in client demand and industry conditions. Any failure by us to design and execute operating model changes that capture opportunities and efficiencies at the intersections of our businesses and maximize the value we deliver to clients and stakeholders could have an adverse impact on our business. Additionally, some of our competitors may have greater financial resources, or may be better positioned to respond to technological and other changes in the industries we serve, and they may be able to compete more effectively. Furthermore, the competition for talent continues to accelerate.

Across our Risk and Insurance Services segment, we operate in a variety of markets and face different competitive landscapes. In addition to the challenges posed by capital market alternatives to traditional insurance and reinsurance, we compete against a wide range of other insurance and reinsurance brokerage and risk advisory firms that operate on a global, regional, national or local scale for both client business and employee talent. In recent years, private equity sponsors have invested tens of billions of dollars into the insurance brokerage sector, transforming existing players and creating new ones to compete with large brokers. We also compete with insurance companies that market and service their insurance products directly to consumers and reinsurance companies that market and service their products directly to insurance companies, in each case without the assistance of brokers or other market intermediaries, and with various other companies that provide risk-related services or alternatives to traditional brokerage services, including those that rely almost exclusively on technological solutions or platforms. This competition is intensified by an often "syndicated" or "distributed" approach to the purchase of insurance and reinsurance brokerage services, where a client engages multiple brokers to service different portions of the client's account. In addition, third party capital providers have entered the insurance and reinsurance risk transfer market offering products and capital directly to our clients that serve as substitutes for traditional insurance.

In our Consulting segment, we compete for business with numerous consulting firms and similar organizations, many of which also provide, or are affiliated with firms that provide, accounting, information systems, technology and financial services. Such competitors may be able to offer more comprehensive products and services to

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potential clients, which may give them a competitive advantage. Some of our competitors also may be able to invest more significant capital in technology and digital solutions. In certain sub-segments, we compete in highly fragmented markets or with start-ups that may be able to offer solutions at a lower price or on more favorable conditions.

In addition, companies in the industries that we serve may seek to achieve economies of scale and other synergies by combining with or acquiring other companies. If two or more of our current clients merge, or consolidate or combine their operations, it may decrease the amount of work that we perform for these clients.

We rely on a large number of vendors and other third parties to perform key functions of our business operations and to provide services to our clients. These vendors and third parties may act or fail to act in ways that could harm our business.

We rely on a large number of vendors and other third parties, and in some cases subcontractors, to provide services, data and information such as technology, information security, funds transfers, business process management, and administration and support functions that are critical to the operations of our business. These third parties include correspondents, agents and other brokers and intermediaries, insurance markets, data providers, plan trustees, payroll service providers, software and system vendors, health plan providers, investment managers, custodians, risk modeling providers, and providers of human resource functions, such as recruiters. Many of these providers are located outside the U.S., which exposes us to business disruptions and political risks inherent when conducting business outside of the U.S. As we do not control many of the actions of these third parties, we are subject to the risk that their decisions or operations may adversely impact us and replacing these service providers could create significant delay in services or operations and additional expense.

A failure by the third parties to (i) comply with service level agreements in a high quality and timely manner, particularly during periods of our peak demand for their services, (ii) maintain adequate internal controls that may impact our own financial reporting, or (iii) adequately maintain the confidentiality of any of our data or trade secrets or adequately protect or properly use other intellectual property to which they may have access, could result in economic and reputational harm to us. These third parties also face their own technology, operating, business and economic risks, and any significant failures by them, including the improper use or disclosure of our confidential client, employee, or Company information or failure to comply with applicable law, could cause harm to our reputation or otherwise expose us to liability. An interruption in or the cessation of service by any service provider as a result of systems failures, capacity constraints, non-compliance with legal, regulatory or contractual obligations, financial difficulties or for any other reason could disrupt our operations, impact our ability to offer certain products and services, and result in contractual or regulatory penalties, liability claims from clients or employees, damage to our reputation and harm to our business.

Business Resiliency Risks

Our inability to successfully recover should we experience a disaster or other business continuity or data recovery problem could cause material financial loss, loss of human capital, regulatory actions, reputational harm or legal liability.

If we experience a local or regional disaster or other business continuity event, such as an earthquake, hurricane, flood, terrorist attack, pandemic, war or other geopolitical tensions, protests or riots, security breach, cyberattack (including manipulating the control systems of critical infrastructure), power loss or telecommunications failure, our ability to operate will depend, in part, on the continued availability of our personnel, our office facilities and the proper functioning of our computer, telecommunication and other related systems and operations. In such an event, we could experience operational challenges that could have a material adverse effect on our business. The risk of business disruption is more pronounced in certain geographic areas, including major metropolitan centers, like New York or London, where we have significant operations and approximately 3,700 and 5,700 colleagues in those respective locations, and in certain countries and regions in which we operate that are subject to higher potential threat of terrorist attacks or military conflicts.

Our operations depend in particular upon our ability to protect our technology infrastructure against damage. If a business continuity event occurs, we could lose client or Company data or experience interruptions to our operations or delivery of services to our clients, which could have a material adverse effect. Such risks have increased significantly due to hybrid and remote work environments. A cyberattack or other business continuity event affecting us or a key vendor or other third party could result in a significant and extended disruption in the functioning of our information technology systems or operations or our ability to recover data, requiring us to incur significant expense to address and remediate or otherwise resolve such issues. For example, hackers have

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increasingly targeted companies by attacking internet-connected industrial control and safety control systems. An extended outage could result in the loss of clients and a decline in our revenues. In the worst case, any manipulation of the control systems of critical infrastructure may even result in the loss of life.

We regularly assess and take steps to improve our existing business continuity, disaster recovery and data recovery plans and key management succession. However, a disaster or other continuity event on a significant scale or affecting certain of our key operating areas within or across regions, or our inability to successfully recover from such an event, could materially interrupt our business operations and result in material financial loss, loss of human capital, regulatory actions, reputational harm, damaged client relationships and legal liability. Our business disruption insurance may also not fully cover, in type or amount, the cost of a successful recovery in the event of such a disruption.

Acquisitions and Dispositions Risks

We face risks when we acquire or dispose of businesses.

We have a history of making acquisitions and investments, including a total of 80 in the period from 2019 to 2023. We may not be able to successfully integrate the businesses that we acquire into our own business, or achieve any expected cost savings or synergies from the integration of such businesses. Subject to standard contractual protections, we may also be responsible for legacy liabilities of companies that we acquire.

In addition, if in the future the performance of our reporting units or an acquired business varies from our projections or assumptions, or estimates about future profitability of our reporting units or an acquired business change, the estimated fair value of our reporting units or an acquired business could change materially and could result in an impairment of goodwill and other acquisition-related intangible assets recorded on our balance sheet or in adjustments in contingent payment amounts. Given the significant size of the Company's goodwill and intangible assets, an impairment could have a material adverse effect on our results of operations in any given period.

We expect that acquisitions will continue to be a key part of our business strategy. Our success in this regard will depend on our ability to identify and compete for appropriate acquisition candidates and to finance and complete the transactions we decide to pursue on favorable terms with positive results.

When we dispose of businesses, we may continue to be subject to certain liabilities of that business after its disposition relating to the prior period of our ownership and may not be able to negotiate for limitations on those liabilities. We are also subject to the risk that the sales price is less than the amount reflected on our balance sheet.

Financial Risks

If we are unable to collect our receivables, our results of operations and cash flows could be adversely affected.

Our business depends on our ability to obtain payment from our clients of the amounts they owe us for the work we perform. As of December 31, 2023, our receivables for our commissions and fees were approximately $5.8 billion, or approximately one-quarter of our total annual revenues, and portions of our receivables are increasingly concentrated in certain businesses and geographies.

Macroeconomic or geopolitical conditions, such as a slower economic growth or recession, the war in Ukraine and the escalating conflict throughout the Middle East, inflationary pressures or supply chain challenges, could result in financial difficulties for our clients, which could cause clients to delay payments to us, request modifications to their payment arrangements that could increase our receivables balance or default on their payment obligations to us.

We may not be able to obtain sufficient financing on favorable terms.

The maintenance and growth of our business, including our ability to finance acquisitions, the payment of dividends and our ability to make share repurchases rely on our access to capital, which depends in large part on cash flow generated by our business and the availability of equity and debt financing. Certain of our businesses also rely on financings by the Company to fund the underwriting of their client's debt and equity capital raising transactions. There can be no assurance that our operations will generate sufficient positive cash flow to finance all of our capital needs or that we will be able to obtain equity or debt financing on favorable terms, particularly in an environment of rising interest rates. In addition, our ability to obtain financing will depend in part upon prevailing conditions in credit and capital markets, which are beyond our control.

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Our defined benefit pension plan obligations could cause the Company's financial position, earnings and cash flows to fluctuate.

Our defined benefit pension obligations and the assets set aside to fund those obligations are sensitive to certain changes in the financial markets. Any such changes may result in increased pension expense or additional cash payments to fund these plans.

The Company has significant defined benefit pension obligations to its current and former employees, totaling approximately $12.2 billion, and related plan assets of approximately $13.5 billion, at December 31, 2023 on a U.S. GAAP basis. The Company's policy for funding its defined benefit pension plans is to contribute amounts at least sufficient to meet the funding requirements set forth by law. In the U.S., contributions to these plans are based on ERISA guidelines. Outside the United States, contributions are generally based on statutory requirements and local funding practices, which may differ from measurements in accordance with U.S. GAAP. In the U.K., for example, the assumptions used to determine pension contributions are the result of legally-prescribed negotiations between the Company and the plan trustees. Currently, the use of these assumptions results in a lower funded status than determined in accordance with U.S. GAAP and may result in contributions irrespective of the U.S. GAAP funded status.

The financial calculations relating to our defined benefit pension plans are complex. Pension plan assets could decrease as the result of poor future asset performance. In addition, the estimated return on plan assets would likely be impacted by changes in the interest rate environment and other factors, including equity valuations, since these factors reflect the starting point used in the Company’s projection models. For example, a reduction in interest rates may result in a reduction in the estimated return on plan assets. Also, pension plan liabilities, periodic pension expense and future funding amounts could increase as a result of a decline in the interest rates we use to discount our pension liabilities, longer lifespans than those reflected in our mortality assumptions, changes in investment markets that result in lower expected returns on assets, actual investment return that is less than the expected return on assets, adverse changes in laws or regulations and other variables. Finally, changes in the aggregated, smoothed asset returns as future years replace prior years, has an impact on both the level and the volatility of pension expense.

While we have taken steps to mitigate the impact of pension volatility on our earnings and cash funding requirements, these strategies may not be successful. Accordingly, given the magnitude of our worldwide pension plans, variations in or reassessment of the preceding or other factors or potential miscalculations relating to our defined benefit pension plans could cause significant fluctuation from year to year in our earnings and cash flow, as well as our pension plan assets and liabilities, and may result in increased levels of contributions to our pension plans.

Our significant non-U.S. operations expose us to exchange rate fluctuations and various risks that could impact our business.

Approximately 53% of our total revenue reported in 2023 was from business outside of the U.S. We are subject to exchange rate movement because we must translate the financial results of our foreign subsidiaries into U.S. dollars and also because some of our subsidiaries receive revenue other than in their functional currencies. Exchange rate movements may change over time, and they could have a material adverse impact on our financial results and cash flows reported in U.S. dollars. For additional discussion, see "Market Risk and Credit Risk-Foreign Currency Risk" in Part II, Item 7A ("Quantitative and Qualitative Disclosures about Market Risk") of this report.

Our quarterly revenues and profitability may fluctuate significantly.

Quarterly variations in revenues and operating results may occur due to several factors. These include:

•the number of client engagements during a quarter;

•the possibility that clients may decide to delay or terminate a current or anticipated project as a result of factors unrelated to our work product or progress;

•fluctuations in capacity and utilization rates and clients' ability to terminate engagements without penalty;

•our net colleague hires and related compensation and benefits expense;

•potential limitations on the clients or industries we serve resulting from increased regulation or changing stakeholder expectations on ESG issues;

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•the impact of changes in accounting standards or in our accounting estimates or assumptions;

•the impact on us or our clients of changes in legislation, regulation and legal guidance or interpretations in the jurisdictions in which we operate, in particular as a result of increased regulatory activity and enforcement;

•seasonality due to the impact of regulatory deadlines, policy renewals and other timing factors to which our clients are subject;

•the success of our acquisitions or investments;

•macroeconomic factors such as changes in foreign exchange rates, interest rates and global public and private capital markets, particularly in the case of Mercer, where fees in its investments business and certain other business lines are derived from the value of assets under management, advisement or administration; and

•general economic conditions, including factors beyond our control affecting economic conditions such as global health crises or pandemics, severe weather, climate change, geopolitical unrest such as the war in Ukraine and the escalating conflict throughout the Middle East, protests and riots or other catastrophic events, since our results of operations are directly affected by the levels of business activity of our clients, which in turn are affected by the level of economic activity in the industries and markets that they serve.

A significant portion of our total operating expenses is relatively fixed in the short term. Therefore, a variation in the number of client assignments or in the timing of the initiation or the completion of client assignments can cause significant variations in quarterly operating results for these businesses.

Credit rating downgrades would increase our financing costs and could subject us to operational risk.

Currently, the Company's senior debt is rated A- by S&P, A3 by Moody's and A- by Fitch. The Company carries a Stable outlook with S&P, Moody's and Fitch.

If we need to raise capital in the future (for example, in order to maintain adequate liquidity, fund maturing debt obligations or finance acquisitions or other initiatives), credit rating downgrades would increase our financing costs, and could limit our access to financing sources. A downgrade to a rating below investment-grade could result in greater operational risks through increased operating costs and increased competitive pressures.

Our current debt level could adversely affect our financial flexibility.

As of December 31, 2023, we had total consolidated debt outstanding of approximately $13.5 billion.

The level of debt outstanding could adversely affect our financial flexibility by reducing our cash flows and our ability to use cash from operations for other purposes, including working capital, dividends to shareholders, share repurchases, acquisitions, capital expenditures and general corporate purposes. In addition, we are subject to risks that, at the time any of our outstanding debt matures, we will not be able to retire or refinance the debt on terms that are acceptable to us.

The current U.S. tax regime has provisions which have unintended consequences and may also impact our tax rate in varying degrees based on where our global income is earned.

Our effective tax rate may fluctuate in the future as a result of the current U.S. tax regime and the continuing issuance of interpretive guidance related to the operations of U.S.-based multinational corporations. These include significant provisions in U.S. income tax law that may have a meaningful impact on our income tax expense and require significant judgments and estimates in interpretation and calculations. Current tax legislation includes, among other provisions, limitations on the deductibility of net interest expense, a minimum tax on most non-U.S. income called Global Intangible Low-Taxed Income ("GILTI"), and the Base Erosion and Anti-Abuse Tax ("BEAT"). In addition, a recently enacted book minimum tax could increase the impact of these provisions on our income tax expense. Given the significant complexity of the rules, and the potential for additional guidance from the U.S. Treasury, the Securities and Exchange Commission, the Financial Accounting Standards Board or other regulatory authorities, recognized impacts in future periods could be significantly different from our current estimates. Such uncertainty may also result in increased scrutiny from, or disagreements with, tax authorities. As a U.S.-domiciled company, any such increases would likely have a disproportionate impact on us compared to our foreign-based competitors.

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Global Operations

We are exposed to multiple risks associated with the global nature of our operations.

We conduct business globally. In 2023, approximately 53% of the Company's total revenue was generated from operations outside the U.S., and over one-half of our employees were located outside the U.S. In addition, we conduct our operations through four separate businesses. Potential conflicts of interest may arise across our businesses given the significant volume of our engagements.

The geographic breadth of our activities also subjects us to significant legal, economic, operational, market, compliance and reputational risks. These include, among others, risks relating to:

•economic and political conditions in the countries in which we operate;

•client concentration in certain high-growth countries in which we operate;

•the length of payment cycles and potential difficulties in collecting accounts receivable;

•unexpected increases in taxes or changes in U.S. or foreign tax laws, rulings, policies or related legal and regulatory interpretations, including recent changes to the U.K. statutory rate;

•the implementation of the Organization for Economic Cooperation and Development (OECD) international tax framework, including the implementation of the Pillar 2 minimum tax regime by key jurisdictions in 2024 and the Pillar 1 profit reallocation regime, which could have an adverse effect on our effective tax rate, tax payments and results of operations;

•international initiatives to require multinational enterprises, like ours, to calculate and report profitability on a country-by-country basis, which could increase scrutiny by, or cause disagreements with, foreign tax authorities;

•potential transfer pricing-related tax exposures that may result from the flow of funds among our subsidiaries and affiliates in the various jurisdictions in which we operate;

•unexpected reassessment by tax authorities of interpretations of existing rules which may require companies to defend previously accepted positions and may create both new and prior-year exposures;

•litigation arising from ongoing and future controversies with tax authorities;

•permanent establishments created due to colleagues traveling to and doing work in countries where the Company has no presence, or living in such countries and working remotely post-pandemic, which are not properly compensated through transfer pricing;

•our ability to obtain dividends or repatriate funds from our non-U.S. subsidiaries, including as a result of the imposition of currency controls and other government restrictions on repatriation in the jurisdictions in which our subsidiaries operate, fluctuations in foreign exchange rates and the imposition of withholding and other taxes on such payments;

•geopolitical tensions, such as the war in Ukraine and the escalating conflict throughout the Middle East, in countries where we operate, international hostilities, international trade disputes, terrorist activities, natural disasters, pandemics, and infrastructure disruptions;

•local investment or other financial restrictions that foreign governments may impose;

•potential lawsuits, investigations, market studies, reviews or other activity by foreign regulatory or law enforcement authorities or legislatively appointed commissions, which may result in potential modifications to our businesses, related private litigation or increased scrutiny from U.S. or other regulators;

•potential costs and difficulties in complying with a wide variety of foreign laws and regulations (including tax systems) administered by foreign government agencies, some of which may conflict with U.S. or other sources of law;

•potential costs and difficulties in complying, or monitoring compliance, with foreign and U.S. laws and regulations that are applicable to our operations abroad, including trade sanctions laws relating to countries such as Afghanistan, Belarus, Cuba, Iran, North Korea, Russia, Syria, Ukraine (Russia-controlled territories) and Venezuela, anti-corruption laws such as the U.S. Foreign Corrupt Practices Act and the U.K. Bribery Act 2010;

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•limitations or restrictions that foreign or U.S. governments and regulators may impose on the products or services we sell, the methods by which we sell our products and services and the manner in which and the amounts we are compensated;

•potential limitations or difficulties in protecting our intellectual property in various foreign jurisdictions;

•limitations that foreign governments may impose on the conversion of currency or the payment of dividends or other remittances to us from our non-U.S. subsidiaries;

•engaging and relying on third parties to perform services on behalf of the Company; and

•potential difficulties in monitoring employees in geographically dispersed locations.

RISKS RELATING TO OUR RISK AND INSURANCE SERVICES SEGMENT

Our Risk and Insurance Services segment, conducted through Marsh and Guy Carpenter, represented 62% of the Company's total revenue in 2023. Our business in this segment is subject to particular risks.

Results in our Risk and Insurance Services segment may be adversely affected by a general decline in economic activity.

Demand for many types of insurance and reinsurance generally rises or falls as economic growth expands or slows. This dynamic affects the level of commissions and fees generated by Marsh and Guy Carpenter. To the extent our clients become adversely affected by declining business conditions, they may choose to limit their purchases of risk services and insurance and reinsurance coverage, as applicable, which would adversely impact our commission revenue and other revenue based on premiums placed and services provided by us. Also, the insurance they seek to obtain through us may be impacted by changes in their assets, property values, sales or number of employees, which may reduce our commission revenue, and they may decide not to purchase our risk advisory or other services, which would inhibit our ability to generate fee revenue. Moreover, insolvencies and combinations associated with an economic downturn, especially insolvencies and combinations in the insurance industry, could adversely affect our brokerage business through the loss of clients or by limiting our ability to place insurance and reinsurance business, as well as our revenues from insurers. Guy Carpenter is especially susceptible to this risk given the limited number of insurance company clients and reinsurers in the marketplace.

Volatility or declines in premiums and other market trends may significantly impede our ability to grow revenues and profitability.

A significant portion of our Risk and Insurance Services revenue consists of commissions paid to us out of the premiums that insurers and reinsurers charge our clients for coverage. We do not determine the insurance premiums on which our commissions are generally based. Our revenues and profitability are subject to change to the extent that premium rates fluctuate or trend in a particular direction. The potential for changes in premium rates is significant, due to the normal cycles of pricing in the commercial insurance and reinsurance markets.

As traditional insurance companies continue to rely on non-affiliated brokers or agents to generate premium, those insurance companies may seek to reduce their expenses by lowering their commission rates. The reduction of these commission rates, along with general volatility or declines in premiums, may significantly affect our revenue and profitability. Because we do not determine the timing or extent of premium pricing changes, it is difficult to accurately forecast our commission revenues, including whether they will significantly decline. As a result, we may have to adjust our plans for future acquisitions, capital expenditures, dividend payments, loan repayments and other expenditures to account for unexpected changes in revenues, and any decreases in premium rates may adversely affect the results of our operations.

In addition to movements in premium rates, our (and Mercer's Health business's) ability to generate premium-based commission revenue may be challenged by disintermediation and the growing availability of alternative methods for clients to meet their risk-protection needs. This trend includes a greater willingness on the part of corporations to self-insure, the expanded use of captive insurers, and the presence of capital markets-based solutions for traditional insurance and reinsurance needs. Further, the profitability of our Risk and Insurance Services segment depends in part on our ability to be compensated for the analytical services and other advice that we provide, including the consulting and analytics services that we provide to insurers. If we are unable to achieve and maintain adequate billing rates for all of our services, our margins and profitability could decline.

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Adverse legal developments and future regulations concerning how intermediaries are compensated by insurers or clients, as well as allegations of anti-competitive behavior or conflicts of interest, could have a material adverse effect on our business, results of operations and financial condition.

The ways in which insurance intermediaries are compensated receive scrutiny from regulators in part because of the potential for anti-competitive behavior and conflicts of interest. The vast majority of the compensation that Marsh receives is in the form of retail fees and commissions that are paid by the client or paid from premium that is paid by the client. The amount of other compensation that we receive from insurance companies, separate from retail fees and commissions, has increased in the last several years, both on an underlying basis and through acquisition and represented approximately 6% of Marsh's revenue in 2023. This other compensation includes payment for (i) consulting and analytics services provided to insurers; (ii) administrative and other services provided to insurers (including underwriting services and services relating to the administration and management of quota shares, panels and other facilities); and (iii) contingent commissions, primarily at MMA and outside the U.S., paid by insurers based on factors such as volume or profitability. These other revenue streams present potential regulatory, litigation and reputational risks that may arise from alleged anti-competitive behavior or conflicts of interest, (including those arising from Guy Carpenter’s role as intermediary and advisor for insurance companies), and future changes in the regulatory environment may impact our ability to collect such revenue. Adverse regulatory, legal or other developments could have a material adverse effect on our business and expose the Company to negative publicity and reputational harm.

RISKS RELATING TO OUR CONSULTING SEGMENT

Our Consulting segment, conducted through Mercer and Oliver Wyman Group, represented 38% of our total revenue in 2023. Our businesses in this segment are subject to particular risks.

Mercer’s Wealth business is subject to a number of risks, including risks related to public and private capital market fluctuations, third-party asset managers and custodians, operations and technology risks, conflicts of interest, ESG and greenwashing, asset performance and regulatory compliance, that, if realized, could result in significant damage to our business.

Mercer’s Investments business provides clients with digital tools, investment consulting and investment management services. Mercer’s Investments business is subject to a number of risks, including risks related to litigation (both by clients and by plan participants, particularly as we increasingly act in a fiduciary capacity), liquidity and market volatility, an inability to obtain contractual limitations of liability for errors & omissions in certain jurisdictions or parts of our business, third-parties, our operations and technology (including the use of AI), trading errors, conflicts of interest, asset performance and regulatory compliance and scrutiny, which could arise in connection with these offerings. For example, Mercer’s manager research or due diligence on an asset manager may fail to uncover material deficiencies or fraud that could result in investment losses to a client. There is a risk that Mercer will fail to properly or timely implement a client’s investment policy or direction, which could cause an incorrect or untimely allocation of client assets among asset classes, asset managers, or strategies. Mercer may also be perceived as making inaccurate or misleading statements regarding the investment strategies of our offerings or investments with respect to ESG or sustainability, commonly referred to as “greenwashing,” or recommending certain asset managers to clients or offering delegated solutions to an investment consulting client, solely to enhance its own compensation or due to other perceived conflicts of interest. Asset classes may perform poorly, or asset managers may underperform their benchmarks, due to poor market performance, a downturn in the global markets, negligence or other reasons, resulting in poor returns or loss of client assets. Changes in the value of equity, debt, currency, real estate, commodities, alternatives or other asset classes, in particular as a result of a downturn in the global markets, could cause the value of assets under management or advisement, and the fees earned by Mercer to decline. Mercer or its clients may be subject to claims or class action litigation relating to advice given or investment decisions made by plan sponsors and plan fiduciaries, particularly relating to 401(k) plans in the U.S. or pension schemes in the U.K. These risks, if realized, could result in significant liability and damage our business.

Revenues for the services provided by our Consulting segment may decline for various reasons, including as a result of changes in economic conditions, the value of equity, debt and other asset classes, our clients’ or an industry's financial condition or government regulation or an accelerated trend away from actively managed investments to passively managed investments.

Global economic conditions, including slower GDP growth or recession, inflationary pressure and foreign exchange rate volatility, may negatively impact businesses and financial institutions. Many of our clients, including

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financial institutions, corporations, government entities and pension plans, have reduced expenses, including amounts spent on consulting services, and used internal resources instead of consultants during difficult economic periods. The evolving needs and financial circumstances of our clients may reduce demand for our consulting services and could adversely affect our revenues and profitability. If the economy or markets in which we operate experience weakness or deteriorate, our business, financial condition and results of operations could be materially and adversely affected. If our clients reduce their headcounts, they will have fewer employee lives covered under their health plans, which may reduce premiums and the commission or supplemental compensation Mercer may receive.

In addition, some of Mercer's Investments business generate fees based upon the value of the clients’ assets under management, advisement or administration. Changes in the value of equity, debt, currency, real estate, commodities, alternatives or other asset classes could cause the value of assets under management, advisement or administration, and the fees received by Mercer, to decline. Such changes could also cause clients to withdraw funds from Mercer’s Investments business in favor of other investment service providers. In either case, our business, financial condition and results of operations could be materially adversely affected. Mercer’s Investments business also could be adversely affected by an accelerated shift away from actively managed investments to passively managed investments with associated lower fees. Further, revenue received by Mercer as investment manager to the majority of the Mercer-managed investment funds is reported in accordance with U.S. GAAP on a gross basis rather than a net basis, with sub-advisor fees reflected as an expense. Therefore, the reported revenue for these offerings does not fully reflect the amount of net revenue ultimately attributable to Mercer.

Demand for many of Mercer's benefits services is affected by government regulation and tax laws, rulings, policies and interpretations, which drive our clients' needs for benefits-related services. Significant changes in government regulations affecting the value, use or delivery of benefits and human resources programs, including changes in regulations relating to health and welfare plans, defined contribution plans or defined benefit plans, may adversely affect the demand for or profitability of Mercer's services.

Factors affecting defined benefit pension plans and the services we provide relating to those plans could adversely affect Mercer.

Mercer currently provides plan sponsors, plan trustees, multi-employer and public entity clients with actuarial, consulting and administration services relating to defined benefit pension plans. The nature of our work is complex. Many clients, particularly in the public sector, have sizeable pension deficits and are subject to impact from volatility in the global markets and interest rate fluctuations. A number of Mercer's clients have frozen or curtailed their defined benefit plans and have moved to defined contribution plans resulting in reduced revenue for Mercer's retirement business. These developments, fee compression pressures, and a continued or accelerated rate of decline in revenues for our defined benefit pension plans business could adversely affect Mercer's business and operating results. In addition, our actuarial services involve numerous assumptions and estimates regarding future and contingent events, including interest rates used to discount future liabilities, estimated rates of return for a plan's assets, healthcare cost trends, salary projections and participants' life expectancies. Mercer's consulting services involve the drafting and interpretation of trust deeds and other complex documentation governing pension plans. Mercer's administration services include calculating benefits within complicated pension plan structures. Mercer's investments services include investment advice and management relating to defined benefit pension plan assets intended to fund present and future benefit obligations. Clients dissatisfied with our services have brought, and may bring, significant claims against us, particularly in the U.S. and the United Kingdom.

Additionally, a rapid rise in interest rates could result in higher defined benefit pension plan funding levels. In some markets, this could accelerate clients’ desire to conduct a buyout or third-party risk transfer. Such a transaction could result in additional short-term revenue for Mercer to the extent we advise the client on the transaction, but a loss in longer term recurring revenue related to the plan.

The profitability of our Consulting segment may decline if we are unable to achieve or maintain adequate utilization and pricing rates for our consultants.

The profitability of our Consulting businesses depends in part on ensuring that our consultants maintain adequate utilization rates (i.e., the percentage of our consultants' working hours devoted to billable activities). Our utilization rates are affected by a number of factors, including:

•general economic conditions;

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•our ability to transition consultants promptly from completed projects to new assignments, and to engage newly-hired consultants quickly in revenue-generating activities;

•our ability to continually secure new business engagements, particularly because a portion of our work is project-based rather than recurring in nature;

•our ability to forecast demand for our services and thereby maintain appropriate headcount in each of our geographies and workforces;

•our ability to retain key colleagues and consulting professionals;

•unanticipated changes in the scope of client engagements;

•the potential for conflicts of interest that might require us to decline client engagements that we otherwise would have accepted;

•our need to devote time and resources to sales, training, professional development and other non-billable activities; and

•the potential disruptive impact of acquisitions and dispositions.

If the utilization rate for our consulting professionals declines, our revenues, profit margin and profitability could decline.

In addition, the profitability of our Consulting businesses depends in part on the prices we are able to charge for our services. The prices we charge are affected by a number of factors, including:

•general economic conditions;

•clients' perception of our ability to add value through our services;

•market demand for the services we provide;

•our ability to develop new services and the introduction of new services by competitors;

•the pricing policies of our competitors; and

•the extent to which our clients develop in-house or other capabilities to perform the services that they might otherwise purchase from us.

If we are unable to achieve and maintain adequate billing rates for our services, our profit margin and profitability could decline.

Item 1B.   Unresolved Staff Comments.

There are no unresolved comments to be reported pursuant to Item 1B.

Item 1C.   Cybersecurity.

As a professional services firm that processes confidential and sensitive information, such as personal information, cybersecurity risk management is an integral part of our enterprise risk management strategy. Our cybersecurity risk management program has been designed based on industry standards, such as the National Institute of Standards and Technology Cybersecurity Framework and ISO/IEC:27001, and provides a framework for assessing cybersecurity risk and identifying and managing cybersecurity threats and incidents, including threats and incidents associated with our use of services, applications and products provided by third-party vendors and service providers.

Our cybersecurity risk management program is coordinated by cross-functional teams, including risk management, legal and compliance, business resiliency management and information security. These teams develop, implement and maintain our compliance policies, programs and training, business resiliency, disaster recovery and information security frameworks, solutions and procedures. They also work closely with our business, internal audit, finance and IT staff to identify, assess and mitigate risks, including those associated with our use of third-party vendors and service providers, and to monitor and take steps designed to prevent security incidents in our technology environment.

Our cybersecurity risk management framework includes (1) procedures designed to assess the data privacy and cybersecurity practices of third-party vendors and service providers (including risk assessments and contractual protections), (2) technical IT controls designed to manage risks associated with cybersecurity incidents (such as

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multifactor authentication and requirements for VPN or private channel access to our systems), and (3) formal policies and procedures designed to address cybersecurity incidents. Our formal policies and procedures designed to address cybersecurity incidents include steps for verifying and assessing the severity of a cybersecurity incident, identifying the source of a cybersecurity incident (including whether it is associated with a third-party service provider) and implementing cybersecurity countermeasures and mitigation strategies. Additionally, we have procedures for informing senior management and our Board of Directors of potentially material cybersecurity incidents. We also periodically engage third-party security consultants to assess our cybersecurity program and to perform penetration testing on our security environment and controls. In addition, cybersecurity training is provided to all newly hired colleagues and then at least annually for all colleagues. We also conduct regular ongoing cybersecurity awareness campaigns and phishing tests and provide training in response to such tests as appropriate.

Our Board of Directors has overall oversight responsibility for the Company’s risk management and receives updates from management throughout the year on cybersecurity matters and other material risks facing the Company. Additionally, the Audit Committee regularly reviews the Company’s policies and practices with respect to risk assessment and risk management, including cybersecurity risks, and reports to the full Board of Directors on a regular basis. The Audit Committee is responsible for overseeing the Company’s enterprise risk management policies and processes, including discussing with management the Company’s major risk exposures and the steps that have been taken to monitor and control such exposures, including those arising from cybersecurity risks.

Management is responsible for identifying, assessing and managing material cybersecurity risks on an ongoing basis. Management’s efforts include establishing processes designed to ensure that potential cybersecurity risks are monitored, putting in place mitigation and remedial measures and implementing and maintaining cybersecurity programs. Our cybersecurity programs are under the direction of our Chief Information Security Officer (CISO), who reports to our Chief Information Officer (CIO). Our CIO has significant expertise and over a decade of experience working in technology. Our CISO has over twenty years of experience working in cybersecurity and maintains a Certified Information Systems Security Professional certification. Our CISO and CIO receive reports from our cybersecurity team and monitor the prevention, detection, mitigation, and remediation of cybersecurity incidents. Our cybersecurity team is comprised of experienced information systems security professionals and information security managers with many years of experience and various security certifications.

Management, including the CIO and CISO, regularly reviews with the Board of Directors and the Audit Committee the Company’s cybersecurity programs, material cybersecurity risks and mitigation strategies and provides updates on notable developments in the cybersecurity threat landscape. Additionally, management follows a risk-based escalation process to notify the Audit Committee outside of the cycle of regular updates when an emerging risk or material issue is identified, such as a potentially significant cybersecurity threat or incident.

In 2023, we did not identify any cybersecurity threats or incidents that have materially affected or are reasonably likely to materially affect the Company, including with respect to our business strategy, results of operations, or financial condition. However, despite our efforts, we cannot eliminate all risks from cybersecurity threats or incidents, or provide assurances that we have not experienced an undetected cybersecurity threat or incident. For more information about these risks, please see “Risk Factors – Cybersecurity, Data Protection and Technology Risks” in this annual report on Form 10-K.

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Item 2.    Properties.

The Company maintains its corporate headquarters in New York City. We also maintain other offices around the world, primarily in leased space. In certain circumstances we may have space that we sublet to third parties, depending upon our needs in particular locations.

The Company and certain of its subsidiaries own, directly and indirectly through special purpose subsidiaries, a 58% condominium interest covering approximately 900,000 square feet of office space in a 44 story condominium in New York City. This real estate serves as the Company's headquarters and is occupied primarily by the Company and its subsidiaries for general corporate use. The condominium interests are financed by a 30-year mortgage loan that is non-recourse to the Company unless the Company (i) is downgraded below B (stable outlook) by S&P or Fitch or B2 (stable outlook) by Moody's and such downgrade is continuing or (ii) an event of default under the mortgage loan has occurred. The mortgage is secured by a first priority assignment of leases and rents, including the leases which the Company and certain of its subsidiaries entered into with their affiliated special purpose subsidiaries which own the mortgaged condominium interests. The net rent due under those leases in effect services the mortgage debt.

Item 3.    Legal Proceedings.

We and our subsidiaries are party to a variety of other legal, administrative, regulatory and government proceedings, claims and inquiries arising in the normal course of business.

Additional information regarding certain legal proceedings and related matters is set forth in Note 16, Claims, Lawsuits and Other Contingencies, in the notes to the consolidated financial statements appearing under Part II, Item 8 ("Financial Statements and Supplementary Data") of this report.

Item 4.    Mine Safety Disclosures.

Not applicable.

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PART II

Item 5.    Market for the Company’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities.

The Company’s common stock is listed on the New York and Chicago Stock Exchanges. Effective as of November 27, 2023, the Company’s common stock was delisted from the London Stock Exchange. The following table indicates the high and low prices (NYSE composite quotations) of the Company’s common stock in 2023 and 2022, and each quarterly period thereof:

	2023 Stock Price Range		2022 Stock Price Range
	High	Low	High	Low
First Quarter	$176.85	$151.86	$173.34	$142.80
Second Quarter	$189.02	$165.86	$183.14	$143.33
Third Quarter	$199.20	$183.81	$174.23	$146.82
Fourth Quarter	$202.81	$184.02	$176.75	$148.14
Full Year	$202.81	$151.86	$183.14	$142.80

The Company has a share repurchases program authorized by the Board of Directors.

The Company repurchased approximately 6.4 million shares of its common stock for $1.15 billion in 2023. At December 31, 2023, the Company remained authorized to repurchase up to approximately $3.2 billion in shares of its common stock. There is no time limit on the authorization. The Company repurchased approximately 12.2 million shares of its common stock for $1.9 billion in 2022.

In March 2022, the Board of Directors of the Company authorized an additional $5 billion in share repurchases. This was in addition to the Company's existing share repurchase program, which had approximately $1.3 billion of remaining authorization at December 31, 2021.

The following information relates to the Company's repurchases of equity securities during each month within the fourth quarter of the fiscal year covered by this report:

Period	Total Number of Shares (or Units) Purchased	Average Price Paid per Share (or Unit)		Total Number of Shares (or Units) Purchased as Part of Publicly Announced Plans or Programs	Maximum Number (or Approximate  Dollar Value) of Shares (or Units) that May Yet Be Purchased Under the Plans or Programs
Oct 1-31, 2023	239,503	$	187.95	239,503	$	3,369,049,645
Nov 1-30, 2023	635,940	$	197.13	635,940	$	3,243,683,847
Dec 1-31, 2023	410,498	$	193.91	410,498	$	3,164,084,989
Total	1,285,941	$	194.39	1,285,941	$	3,164,084,989

At February 8, 2024, there were 4,044 stockholders of record.

Item 6.    [Reserved].

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Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

General

Marsh & McLennan Companies Inc., and its consolidated subsidiaries (the "Company") is a global professional services firm in the areas of risk, strategy and people. The Company helps clients build the confidence to thrive through the power of perspective of its four market-leading businesses. With annual revenue of $23 billion, the Company has more than 85,000 colleagues advising clients in over 130 countries.

Marsh provides data-driven risk advisory services and insurance solutions to commercial and consumer clients. Guy Carpenter develops advanced risk, reinsurance and capital strategies that help clients grow profitably and pursue emerging opportunities. Mercer delivers advice and technology-driven solutions that help organizations redefine the world of work, reshape retirement and investment outcomes, and unlock health and well-being for a changing workforce. Oliver Wyman Group serves as a critical strategic, economic and brand advisor to private sector and governmental clients. The four businesses also collaborate together to deliver new solutions to help clients manage complex and interconnected risks.

The Company conducts business through two segments:

•Risk and Insurance Services includes risk management activities (risk advice, risk transfer and risk control and mitigation solutions) as well as insurance and reinsurance broking and services. The Company conducts business in this segment through Marsh and Guy Carpenter.

•Consulting includes health, wealth and career advice, solutions and products, and specialized management, strategic, economic and brand consulting services. The Company conducts business in this segment through Mercer and Oliver Wyman Group.

The results of operations in the Management Discussion & Analysis ("MD&A") include an overview of the Company’s consolidated 2023 results compared to the 2022 results, and should be read in conjunction with the consolidated financial statements and notes. This section also includes a discussion of the key drivers impacting the Company’s financial results of operations both on a consolidated basis and by reportable segments.

We describe the primary sources of revenue and categories of expense for each segment in the discussion of segment financial results. A reconciliation of segment operating income to total operating income is included in Note 17, Segment Information, in the notes to the consolidated financial statements included in Part II, Item 8, of this report.

For information and comparability of the Company's results of operations and liquidity and capital resources for fiscal year 2021, refer to "Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations" of the Company's Form 10-K for the fiscal year ended December 31, 2022.

This MD&A contains forward-looking statements as defined in the Private Securities Litigation Reform Act of 1995. Refer to "Information Concerning Forward-Looking Statements" at the outset of this report.

Non-GAAP Measures

The Company reports its financial results in accordance with accounting principles generally accepted in the United States (U.S.), referred to as in accordance with "GAAP" or "reported" results. The Company also refers to and presents a non-GAAP financial measure in non-GAAP revenue, within the meaning of Regulation G and Item 10(e) of Regulation S-K in accordance with the Securities Exchange Act of 1934. The Company has included a reconciliation of this non-GAAP financial measure to the most directly comparable financial measure calculated in accordance with GAAP as part of the consolidated revenue and expense discussion. Percentage changes, referred to as non-GAAP underlying revenue, are calculated by dividing the period over period change in non-GAAP revenue by the prior period non-GAAP revenue.

The Company believes this non-GAAP financial measure provides useful supplemental information that enables investors to better compare the Company’s performance across periods. Management also uses this measure internally to assess the operating performance of its businesses and to decide how to allocate resources. However, investors should not consider this non-GAAP measure in isolation from, or as a substitute for, the financial information that the Company reports in accordance with GAAP. The Company's non-GAAP measure includes adjustments that reflect how management views its businesses and may differ from similarly titled non-GAAP measures presented by other companies.

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Financial Highlights

•Consolidated revenue in 2023 was $22.7 billion, an increase of 10%, or 9% on an underlying basis.

•Consolidated operating income increased $1.0 billion, or 23% to $5.3 billion in 2023, compared to 2022. Net income attributable to the Company was $3.8 billion. Earnings per share on a diluted basis increased to $7.53 from $6.04, or 25%, compared with 2022.

•Risk and Insurance Services revenue in 2023 was $14.1 billion, an increase of 11%, on a reported and underlying basis. Operating income was $3.9 billion and $3.1 billion in 2023 and 2022, respectively.

•Consulting revenue in 2023 was $8.7 billion, an increase of 7%, on a reported and underlying basis. Operating income was $1.7 billion and $1.6 billion in 2023 and 2022, respectively.

•The Company's results of operations in 2023 were impacted by restructuring activities of $301 million, primarily related to severance and lease exit charges for activities focused on workforce actions, technology rationalization and reductions in real estate.

•The Company completed 14 acquisitions in 2023, the largest being the acquisitions of Honan Insurance Group and Graham Company in the Risk and Insurance Services segment.

•In the Consulting segment, the Company completed the acquisition of Westpac Banking Corporation’s ("Westpac") financial advisory business, Advance Asset Management, and the transfer from Westpac of BT Financial Group's personal and corporate pension funds to the Mercer Super Trust managed by Mercer Australia (referred to collectively, as the "Westpac Transaction").

•In September 2023, the Company issued $600 million of 5.400% senior notes due 2033 and $1.0 billion of 5.700%% senior notes due 2053. In March 2023, the Company issued $600 million of 5.450% senior notes due 2053.

•On October 16, 2023, the Company repaid $250 million of senior notes that matured.

•In 2023, the Company repurchased 6.4 million shares for $1.15 billion.

The macroeconomic and geopolitical environment including multiple major wars, escalating conflict throughout the Middle East and rising tension in the South China Sea, slower GDP growth or recession, lower interest rates, capital markets volatility and inflation has and could continue to potentially impact our business, financial condition, results of operations and cash flows. For more information about these risks, please see “Risk Factors – Macroeconomic Risks” in this annual report on Form 10-K.

For additional details, refer to the Consolidated Results of Operations and Liquidity and Capital Resources sections in this MD&A.

Acquisitions and dispositions impacting the Risk and Insurance Services and Consulting segments are discussed in Note 5, Acquisitions and Dispositions, in the notes to the consolidated financial statements.

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Consolidated Results of Operations

For the Years Ended December 31, (In millions, except per share data)	2023		2022		2021
Revenue	$	22,736	$	20,720	$	19,820
Expense:
Compensation and benefits	13,099		12,071		11,425
Other operating expenses	4,355		4,369		4,083
Operating expenses	17,454		16,440		15,508
Operating income	$	5,282	$	4,280	$	4,312
Income before income taxes	$	5,026	$	4,082	$	4,208
Net income before non-controlling interests	$	3,802	$	3,087	$	3,174
Net income attributable to the Company	$	3,756	$	3,050	$	3,143
Net income per share attributable to the Company
– Basic	$	7.60	$	6.11	$	6.20
– Diluted	$	7.53	$	6.04	$	6.13
Average number of shares outstanding:
– Basic	494		499		507
– Diluted	499		505		513
Shares outstanding at December 31,	492		495		504

Consolidated operating income increased $1.0 billion, or 23% to $5.3 billion in 2023, compared to $4.3 billion in the prior year, reflecting a 10% increase in revenue and a 6% increase in expenses. Revenue growth was driven by increases in the Risk and Insurance Services and Consulting segments of 11% and 7%, respectively.

The increase in revenue in 2023 reflects the continued demand for our advice and solutions, growth in new business and renewals, and investments in talent and capabilities. Results also benefited from growth in the global economy, inflation, higher insurance and reinsurance pricing, and an increase in fiduciary income due to higher interest rates.

Expenses increased in 2023 primarily due to compensation and benefits, driven by increased headcount, and higher base salary and incentive compensation. Other operating expenses decreased due to lower restructuring and facility costs, partially offset by higher travel and entertainment costs compared to 2022. Expenses in 2023 also include $51 million of insurance and indemnity recoveries for a legacy Jardine Lloyd Thompson Group plc ("JLT") Errors and Omissions ("E&O") matter relating to suitability of advice provided to individuals for defined benefit pension transfers in the United Kingdom (U.K).

Diluted earnings per share increased to $7.53 from $6.04, or 25% from the prior year. The increase is primarily the result of higher operating income in 2023, compared to the prior year.

Consolidated Revenue and Expense

Revenue – Non-GAAP Revenue and Components of Change

The Company advises clients in over 130 countries. As a result, foreign exchange rate movements may impact period over period comparisons of revenue. Similarly, certain other items such as acquisitions and dispositions, including transfers among businesses, may impact period over period comparisons of revenue. Non-GAAP revenue measures the change in revenue from one period to the next by isolating these impacts on an underlying revenue basis. Percentage changes, referred to as non-GAAP underlying revenue, are calculated by dividing the period over period change in non-GAAP revenue by the prior period non-GAAP revenue.

The non-GAAP revenue measure is presented on a constant currency basis excluding the impact of foreign currency fluctuations. The Company isolates the impact of foreign exchange rate movements period over period, by translating the current period foreign currency GAAP revenue into U.S. Dollars based on the difference in the current and corresponding prior period exchange rates.

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The percentage change for acquisitions, dispositions, and other includes the impact of current and prior year items excluded from the calculation of non-GAAP underlying revenue for comparability purposes. Details on these items are provided in the reconciliation of non-GAAP revenue to GAAP revenue tables.

The following tables present the Company's non-GAAP revenue for the years ended December 31, 2023 and 2022 and the related non-GAAP underlying revenue change:

Year Ended December 31, (In millions, except percentages)	GAAP Revenue				% Change GAAP Revenue*		Non-GAAP Revenue				Non-GAAP Underlying Revenue*
	2023		2022				2023		2022
Risk and Insurance Services
Marsh	$	11,378	$	10,505	8	%	$	11,339	$	10,510	8	%
Guy Carpenter	2,258		2,020		12	%	2,194		2,001		10	%
Subtotal	13,636		12,525		9	%	13,533		12,511		8	%
Fiduciary interest income	453		120				454		120
Total Risk and Insurance Services	14,089		12,645		11	%	13,987		12,631		11	%
Consulting
Mercer	5,587		5,345		5	%	5,621		5,277		7	%
Oliver Wyman Group	3,122		2,794		12	%	3,028		2,805		8	%
Total Consulting	8,709		8,139		7	%	8,649		8,082		7	%
Corporate Eliminations	(62)		(64)				(62)		(64)
Total Revenue	$	22,736	$	20,720	10	%	$	22,574	$	20,649	9	%

The following table provides more detailed revenue information for certain of the components presented in the previous table:

Year Ended December 31, (In millions, except percentages)	GAAP Revenue				% Change GAAP Revenue*		Non-GAAP Revenue				Non-GAAP Underlying Revenue*
	2023		2022				2023		2022
Marsh:
EMEA (a)	$	3,262	$	2,997	9	%	$	3,268	$	3,005	9	%
Asia Pacific (a)	1,295		1,215		7	%	1,327		1,215		9	%
Latin America	559		502		11	%	566		502		13	%
Total International	5,116		4,714		9	%	5,161		4,722		9	%
U.S./Canada	6,262		5,791		8	%	6,178		5,788		7	%
Total Marsh	$	11,378	$	10,505	8	%	$	11,339	$	10,510	8	%
Mercer:
Wealth	$	2,507	$	2,366	6	%	$	2,537	$	2,435	4	%
Health	2,061		2,017		2	%	2,063		1,880		10	%
Career	1,019		962		6	%	1,021		962		6	%
Total Mercer	$	5,587	$	5,345	5	%	$	5,621	$	5,277	7	%

(a)In the first quarter of 2023, the Company began reporting the Marsh India operations in EMEA. Prior year results for India have been reclassified from Asia Pacific to EMEA for comparative purposes.

(*) Rounded to whole percentages.

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Revenue – Reconciliation of Non-GAAP Measures

The following table provides the reconciliation of GAAP revenue to Non-GAAP revenue for the years ended December 31, 2023 and 2022:

	2023								2022
Year Ended December 31, (In millions)	GAAP Revenue		Currency Impact		Acquisitions/ Dispositions/ Other Impact		Non-GAAP Revenue		GAAP Revenue		Acquisitions/ Dispositions/ Other Impact		Non-GAAP Revenue
Risk and Insurance Services
Marsh (a)	$	11,378	$	70	$	(109)	$	11,339	$	10,505	$	5	$	10,510
Guy Carpenter (b)	2,258		16		(80)		2,194		2,020		(19)		2,001
Subtotal	13,636		86		(189)		13,533		12,525		(14)		12,511
Fiduciary interest income	453		1		—		454		120		—		120
Total Risk and Insurance Services	14,089		87		(189)		13,987		12,645		(14)		12,631
Consulting
Mercer (c)	5,587		23		11		5,621		5,345		(68)		5,277
Oliver Wyman Group (a)	3,122		(15)		(79)		3,028		2,794		11		2,805
Total Consulting	8,709		8		(68)		8,649		8,139		(57)		8,082
Corporate Eliminations	(62)		—		—		(62)		(64)		—		(64)
Total Revenue	$	22,736	$	95	$	(257)	$	22,574	$	20,720	$	(71)	$	20,649

The following table provides more detailed revenue information for certain of the components presented in the previous table:

	2023								2022
Year Ended December 31, (In millions)	GAAP Revenue		Currency Impact		Acquisitions/ Dispositions/ Other Impact		Non-GAAP Revenue		GAAP Revenue		Acquisitions/ Dispositions/ Other Impact		Non-GAAP Revenue
Marsh:
EMEA (a) (d)	$	3,262	$	12	$	(6)	$	3,268	$	2,997	$	8	$	3,005
Asia Pacific (d)	1,295		37		(5)		1,327		1,215		—		1,215
Latin America	559		6		1		566		502		—		502
Total International	5,116		55		(10)		5,161		4,714		8		4,722
U.S./Canada	6,262		15		(99)		6,178		5,791		(3)		5,788
Total Marsh	$	11,378	$	70	$	(109)	$	11,339	$	10,505	$	5	$	10,510
Mercer:
Wealth (c)	$	2,507	$	11	$	19	$	2,537	$	2,366	$	69	$	2,435
Health (c)	2,061		4		(2)		2,063		2,017		(137)		1,880
Career	1,019		8		(6)		1,021		962		—		962
Total Mercer	$	5,587	$	23	$	11	$	5,621	$	5,345	$	(68)	$	5,277
(a)Acquisitions, dispositions, and other in 2022 includes the loss on deconsolidation of the Company's Russian businesses at Marsh of $27 million and Oliver Wyman Group of $12 million. (b)Acquisitions, dispositions, and other in 2023 includes a gain from a legal settlement with a competitor of $58 million, excluding legal fees. (c)Acquisitions, dispositions, and other in 2022 includes revenue from the Westpac Transaction in Wealth and a gain from the sale of the Mercer U.S. affinity business of $112 million in Health. Results for 2023 in Wealth include the loss on sale of an individual financial advisory business in Canada of $17 million. (d)In the first quarter of 2023, the Company began reporting the Marsh India operations in EMEA. Prior year results for India have been reclassified from Asia Pacific to EMEA for comparative purposes.

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Consolidated Revenue

Consolidated revenue increased $2.0 billion, or 10%, to $22.7 billion in 2023, compared to $20.7 billion in 2022. Consolidated revenue increased 9% on an underlying basis and 1% from acquisitions. On an underlying basis, revenue increased 11% and 7% in 2023, in the Risk and Insurance Services and Consulting segments, respectively.

Underlying revenue growth in the Risk and Insurance Services and Consulting segments in 2023 reflect the continued demand for our advice and solutions. In Risk and Insurance Services, the increase in underlying revenue was primarily due to growth in new business and renewals. Results also benefited from growth in the global economy, inflation, higher insurance and reinsurance pricing, and an increase in fiduciary income due to higher interest rates. In Consulting, revenue growth reflects continued demand for our health, wealth, and career solutions and products, and consulting services.

Consolidated Operating Expenses

Consolidated operating expenses increased $1.0 billion, or 6%, to $17.5 billion in 2023, compared to $16.4 billion in 2022. Expenses reflect a 2% increase from acquisitions. Expenses excluding the impact from acquisitions, increased 5% in 2023, with increases of 5% in both the Risk and Insurance Services and Consulting segments.

Expenses increased in 2023 primarily due to compensation and benefits driven by increased headcount, and higher base salary and incentive compensation. Other operating expenses decreased due to lower restructuring and facility costs, partially offset by higher travel and entertainment costs compared to 2022. The Company incurred a total of $301 million for restructuring activities in 2023, compared to $427 million in 2022. Expenses in 2023 also include $51 million of insurance and indemnity recoveries for a legacy JLT E&O matter relating to suitability of advice provided to individuals for defined benefit pension transfers in the U.K.

Restructuring activities

In the fourth quarter of 2022, the Company initiated activities focused on workforce actions, rationalization of technology and functional services, and reductions in real estate. The Company anticipates total charges related to these activities to be approximately $475 million. Through December 31, 2023, the Company has incurred $441 million of these restructuring costs, primarily related to severance and lease exit charges, of which $222 million were incurred in 2023. Any remaining costs are expected to be incurred by the end of 2024. Related estimated savings are expected to be approximately $400 million, with $230 million realized in 2023. The majority of the remaining savings are expected to be realized in 2024. The Company continues to refine its detailed plans for each business and location, which may change the expected timing, estimates of expected costs and related savings.

Restructuring activities also reflect JLT integration and restructuring costs in 2023 of $31 million, compared to $115 million in 2022, primarily related to lease exit charges for a legacy JLT U.K. location. For additional details, refer to Note 14, Restructuring Costs, in the notes to the consolidated financial statements.

Risk and Insurance Services

In the Risk and Insurance Services segment, the Company’s subsidiaries and other affiliated entities act as brokers, agents or consultants for insureds, insurance underwriters and other brokers in the areas of risk management, insurance broking, insurance program management, risk consulting, analytical modeling and alternative risk financing services, primarily under the brand of Marsh, and engage in specialized reinsurance broking expertise, strategic advisory services and analytics solutions, primarily under the brand of Guy Carpenter.

Marsh and Guy Carpenter are compensated for brokerage and consulting services through commissions and fees. Commission rates and fees vary in amount and can depend on a number of factors, including the type of insurance or reinsurance coverage provided, the particular insurer or reinsurer selected, and the capacity in which the broker acts and negotiates with clients. Revenues can be affected by premium rate levels in the insurance/reinsurance markets, the amount of risk retained by insurance and reinsurance clients, and by the value of the risks that have been insured since commission-based compensation is frequently related to the premiums paid by insureds and reinsureds. In many cases, fee compensation may be negotiated in advance, based on the type of risk, coverage required and service provided by the Company and ultimately, the extent of the risk placed into the insurance market or retained by the client. The trends and comparisons of revenue from one period to the next can be affected by changes in premium rate levels, fluctuations in client risk retention and increases or decreases

41

in the value of risks that have been insured, as well as new and lost business, and the volume of business from new and existing clients.

In addition to compensation from its clients, Marsh also receives other compensation, separate from retail fees and commissions, from insurance companies. This other compensation includes, among other things, payment for consulting and analytics services provided to insurers; compensation for administrative and other services (including fees for underwriting services and services provided to or on behalf of insurers relating to the administration and management of quota shares, panels and other facilities in which insurers participate); and contingent commissions, which are paid by insurers based on factors such as volume or profitability of Marsh's placements, primarily driven by Marsh McLennan Agency ("MMA") and parts of Marsh's international operations.

Marsh and Guy Carpenter receive interest income on certain funds (such as premiums and claims proceeds) held in a fiduciary capacity for others. The investment of fiduciary funds is regulated by state and other insurance authorities. These regulations typically require segregation of fiduciary funds and limit the types of investments that may be made. Interest income from these investments varies depending on the amount of funds invested and applicable interest rates, both of which vary from time to time. For presentation purposes, fiduciary interest income is segregated from the other revenues of Marsh and Guy Carpenter and separately presented within the segment, as shown in the previous revenue by segments tables.

The results of operations for the Risk and Insurance Services segment are as follows:

(In millions, except percentages)	2023			2022			2021
Revenue	$	14,089		$	12,645		$	12,085
Compensation and benefits (a)	7,702			7,101			6,656
Other operating expenses (a)	2,442			2,455			2,349
Operating expenses	10,144			9,556			9,005
Operating income	$	3,945		$	3,089		$	3,080
Operating income margin	28.0		%	24.4		%	25.5		%

(a)In 2023, the Company reclassified certain amounts between Compensation and benefits and Other operating expenses for each reporting segment. The reclassification had no impact on consolidated or reporting segment total expenses. Prior period amounts were reclassified for comparability purposes.

Revenue

Revenue in the Risk and Insurance Services segment increased $1.4 billion, or 11%, to $14.1 billion in 2023, compared to $12.6 billion in 2022. Revenue increased 11% on an underlying basis and 1% from acquisitions, partially offset by a decrease of 1% from the impact of foreign currency translation. Interest earned on fiduciary funds increased by $333 million to $453 million in 2023, compared to $120 million in the prior year.

The increase in revenue on an underlying basis in the Risk and Insurance Services segment in 2023 was primarily due to growth in new business and renewals. Results also benefited from growth in the global economy, inflation, higher insurance and reinsurance pricing, and an increase in fiduciary income due to higher interest rates.

Marsh's revenue increased $873 million, or 8%, to $11.4 billion in 2023, compared to $10.5 billion in 2022. This reflects increases of 8% on an underlying basis and 1% from acquisitions, partially offset by a decrease of 1% from the impact of foreign currency translation. U.S./Canada rose 7% on an underlying basis. Total International operations produced underlying revenue growth of 9%, reflecting growth of 13% in Latin America and 9% in each of EMEA and Asia Pacific.

Revenue in 2022 also included a loss of $27 million related to the deconsolidation of the Company's Russian businesses.

Guy Carpenter's revenue increased $238 million, or 12%, to $2.3 billion in 2023, compared to $2.0 billion in 2022. This reflects increases of 10% on an underlying basis and 3% from acquisitions, partially offset by a decrease of 1% from the impact of foreign currency translation. Revenue in 2023 also includes a gain from a legal settlement with a competitor for $58 million, excluding legal fees.

Risk and Insurance Services segment completed 9 acquisitions in 2023. Information regarding these acquisitions is included in Note 5, Acquisitions and Dispositions, in the notes to the consolidated financial statements.

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Operating Expenses

Expenses in the Risk and Insurance Services segment increased $588 million, or 6%, to $10.1 billion in 2023, compared to $9.6 billion in 2022. Expenses reflect a 1% increase from acquisitions.

Expenses in 2023 increased primarily due to compensation and benefits driven by increased headcount, and higher base salary and incentive compensation. Other operating expenses decreased due to lower restructuring and facility costs, partially offset by higher travel and entertainment costs compared to 2022. In 2023, the Company incurred a total of $177 million restructuring costs in Risk and Insurance Services, compared to $254 million in 2022, primarily related to activities initiated in the fourth quarter of 2022, focused on workforce actions, rationalization of technology and functional services, and reductions in real estate and lease exit charges for a legacy JLT U.K. location. Expenses in 2022, also included settlement charges and legal costs related to strategic recruiting of $30 million.

Consulting

The Company conducts business in its Consulting segment through Mercer and Oliver Wyman Group. Mercer delivers advice and technology-driven solutions that help organizations redefine the world of work, reshape retirement and investment outcomes, and unlock health and well-being for a changing workforce. Oliver Wyman Group serves as critical strategic, economic and brand advisor to private sector and governmental clients.

The major component of revenue in the Consulting business is fees paid by clients for advice and services. Mercer, principally through its health line of business, also earns revenue in the form of commissions received from insurance companies for the placement of group (and occasionally individual) insurance contracts, primarily life, health and accident coverages. Revenue for Mercer’s investment management business and certain of Mercer’s defined benefit and contribution administration services consists principally of fees based on assets under management or administration. For a majority of the Mercer managed investment funds, revenue is recorded on a gross basis with sub-advisor fees included in other operating expenses.

Revenue in the Consulting segment is affected by, among other things, global economic conditions, including changes in clients’ particular industries and markets. Revenue is also affected by competition due to the introduction of new products and services, broad trends in employee demographics, including levels of employment and the effect of government policies and regulations. Revenues from investment management services and retirement trust and administrative services are significantly affected by the level of assets under management or administration, which is impacted by securities market performance.

The results of operations for the Consulting segment are as follows: 

(In millions, except percentages)	2023			2022			2021
Revenue	$	8,709		$	8,139		$	7,789
Compensation and benefits (a)	5,249			4,827			4,632
Other operating expenses (a)	1,794			1,759			1,653
Operating expenses	7,043			6,586			6,285
Operating income	$	1,666		$	1,553		$	1,504
Operating income margin	19.1		%	19.1		%	19.3		%

(a)In 2023 the Company reclassified certain amounts between Compensation and benefits and Other operating expenses for each reporting segment. The reclassification had no impact on consolidated or reporting segment total expenses. Prior period amounts were reclassified for comparability purposes.

On January 1, 2024, the Company sold its Mercer U.S. health and benefits and U.K. pension administration businesses for approximately $110 million. The Company expects the gain on sale and the impact on Consulting segment revenues and operating income not to be material.

Revenue

Consulting revenue increased $570 million, or 7%, to $8.7 billion in 2023, compared to $8.1 billion in 2022. This reflects an increase of 7% on an underlying basis.

Mercer's revenue increased $242 million, or 5%, to $5.6 billion in 2023, compared to $5.3 billion in 2022. This reflects an increase of 7% on an underlying basis, partially offset by a decrease of 1% primarily from the

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disposition of businesses. On an underlying basis, revenue for Health, Career and Wealth increased 10%, 6%, and 4%, respectively, as compared to the prior year.

The increase in revenue on an underlying basis at Mercer in 2023 was primarily due to the continued demand for our health, wealth, and career solutions and products. Health continued to benefit from growth in new business, higher retention, increased enrolled lives, and medical inflation. The increase in Career products and services was due to continued demand in rewards and talent strategy. Revenue in Wealth on an underlying basis grew in defined benefit consulting and investment management fees due to the Westpac Transaction, a rebound in capital markets, and positive net flows.

Revenue in 2023 included a loss of $17 million related to the sale of an individual financial advisory business in Canada. Results in 2022 also included a gain of $112 million from the sale of the Mercer U.S. affinity business.

Oliver Wyman Group's revenue increased $328 million, or 12%, to $3.1 billion in 2023, compared to $2.8 billion in 2022. This reflects increases of 8% on an underlying basis, 3% from acquisitions, and 1% from the impact of foreign currency translation.

The increase in underlying revenue at Oliver Wyman Group in 2023 reflects broad-based growth across capabilities led by growth in the Middle East and Europe. Revenue in 2022 also included a loss of $12 million related to the deconsolidation of the Company's Russian businesses.

The Consulting segment completed 5 acquisitions in 2023. Information regarding these acquisitions is included in Note 5, Acquisitions and Dispositions, in the notes to the consolidated financial statements.

Operating Expenses

Expenses in the Consulting segment increased $457 million, or 7%, to $7.0 billion in 2023, compared to $6.6 billion in 2022. Expenses reflect an increase of 2% from acquisitions.

Expenses in 2023 increased primarily due to compensation and benefits driven by increased headcount and higher base salary. The increase in expenses is partially offset by $51 million of insurance recoveries for a legacy JLT E&O matter relating to suitability of advice provided to individuals for defined pension transfers in the U.K.

In 2023, the Company incurred $62 million of total restructuring cost in the Consulting segment, compared to $77 million in the prior year, primarily related to the Company's activities initiated in the fourth quarter of 2022, focused on workforce actions, rationalization of technology and functional services, and reductions in real estate.

Expenses also reflect acquisition and integration related costs for the Westpac Transaction of $39 million, compared to $21 million in 2022.

Corporate and Other

Corporate expenses decreased $33 million, or 9%, to $329 million in 2023, compared to $362 million in 2022. The decrease in expenses reflects a 1% impact from foreign currency translation and lower facility and equipment costs in the current year.

Interest Income

Interest income was $78 million in 2023, compared to $15 million in 2022. Interest income increased $63 million in 2023, due to an increase in corporate funds and higher interest rates.

Interest Expense

Interest expense was $578 million in 2023, compared to $469 million in 2022. Interest expense increased $109 million in 2023, primarily due to an increase in long-term debt and higher interest rates.

Investment Income

The caption "Investment income" in the consolidated statements of income comprises realized and unrealized gains and losses from investments. It includes, when applicable, other than temporary declines in the value of securities, mark-to-market increases or decreases in equity investments with readily determinable fair values and equity method gains or losses on its investments in private equity funds. The Company's investments may include direct investments in insurance, consulting or other strategically linked companies and investments in private equity funds. The Company recorded net investment income of $5 million in 2023, compared to $21 million in 2022. The decrease in 2023 is primarily driven by lower mark-to-market gains from the Company's private equity investments compared to the prior year.

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Income and Other Taxes

The Company's consolidated effective tax rate for 2023 and 2022 was 24.3% and 24.4%, respectively.

The tax rates in both years reflect the impact of discrete tax matters such as excess tax benefits related to share-based compensation, enacted tax legislation, changes in uncertain tax positions, deferred tax adjustments, non-taxable adjustments related to contingent consideration for acquisitions, and valuation allowances for certain tax credits. The 2023 effective tax rate reflects the previously-enacted change in the U.K. corporate income tax rate from 19% to 25%, which was effective April 1, 2023. The blended U.K. statutory tax rate for 2023 is 23.5%. The 2022 effective tax rate also reflects tax benefits from planning that postponed the utilization of U.K. tax losses to future years when the U.K. statutory tax rate will be 25%.

In 2023, the Company released valuation allowances related to its non-U.S. operations. Management determined that there is sufficient positive evidence to conclude that it is more likely than not that deferred tax assets are realizable, primarily due to the sustained profitability of its operations. The valuation allowance release resulted in a decrease to tax expense of $94 million in the current year.

The effective tax rate may vary significantly from period to period. The effective tax rate is sensitive to the geographic mix of earnings and the cost to repatriate the Company's earnings, which may result in higher or lower effective tax rates. Therefore, a shift in the mix of profits among jurisdictions, or changes in the Company's repatriation strategy to access offshore cash, can affect the effective tax rate. In 2023, pre-tax income in the U.K., Canada, Barbados, Ireland, Bermuda, India, United Arab Emirates, Japan, and Australia accounted for approximately 65% of the Company's total non-U.S. pre-tax income, with effective rates in those countries of 20.0%, 27.3%, 1.2%, 23.2%, (18.8)%, 26.0%, 17.3%, 37.6%, and 26.0%, respectively.

In addition, losses in certain jurisdictions cannot be offset by earnings from other operations and may require valuation allowances that affect the rate in a particular period, depending on estimates of the value of associated deferred tax assets which can be realized. A valuation allowance was recorded to reduce deferred tax assets to the amount that the Company believes is more likely than not to be realized. Details are provided in Note 7, Income Taxes, in the notes to the consolidated financial statements. The effective tax rate is also sensitive to changes in unrecognized tax benefits, including the impact of settled tax audits and expired statutes of limitations.

Changes in tax laws, rulings, policies or related legal and regulatory interpretations occur frequently and may also have significant favorable or adverse impacts on our effective tax rate. In July 2023, the U.K. enacted legislation to implement Pillar 2 of the Organization for Economic Cooperation and Development's ("OECD") framework, effective from January 1, 2024. This minimum tax will be treated as a period cost in future years and does not impact operating results for 2023. Other countries in the European Union (E.U.) and elsewhere have similarly adopted legislation. The Company is continuing to monitor legislative developments, especially in the E.U. countries, and is in the process of evaluating the potential impact of the U.K. and other enacted legislation on its results of future operations. Currently, the Company does not expect the impact of Pillar 2 related legislation to be material in 2024.

On August 16, 2022, the Inflation Reduction Act of 2022 ("IRA") was enacted into law. The Company evaluated the provisions of the IRA, the most significant of which are the corporate alternative minimum tax and the share repurchase tax. The IRA was effective as of January 1, 2023, and does not have a significant impact on the Company's financial results of operations for the current year.

As a U.S.-domiciled parent holding company, the Company is the issuer of essentially all of the Company's external indebtedness, and incurs the related interest expense in the U.S. The Company’s interest expense deductions are not currently limited. Further, most senior executive and oversight functions are conducted in the U.S. and the associated costs are incurred primarily in the U.S. Some of these expenses may not be deductible in the U.S., which may impact the effective tax rate.

Changes to the U.S. tax law in recent years have allowed the Company to repatriate foreign earnings without incurring additional U.S. federal income tax costs as foreign income is generally already taxed in the U.S. However, permanent reinvestment continues to be a component of the Company's global capital strategy. The Company continues to evaluate its global investment and repatriation strategy in light of our capital requirements and potential costs of repatriation, which are generally limited to local country withholding taxes.

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Liquidity and Capital Resources

The Company is organized as a legal entity separate and distinct from its operating subsidiaries. As the Company does not have significant operations of its own, the Company is dependent upon dividends and other payments from its operating subsidiaries to pay principal and interest on its outstanding debt obligations, pay dividends to shareholders, repurchase its shares and pay corporate expenses. The Company can also provide financial support to its operating subsidiaries for acquisitions, investments and certain parts of their business that require liquidity, such as the capital markets business of Guy Carpenter. Other sources of liquidity include borrowing facilities in financing cash flows.

The Company derives a significant portion of its revenue and operating profit from operating subsidiaries located outside of the U.S. Funds from those operating subsidiaries are regularly repatriated to the U.S. out of annual earnings. At December 31, 2023, the Company had approximately $1.2 billion of cash and cash equivalents in its foreign operations, which includes $462 million of operating funds required to be maintained for regulatory requirements or as collateral under certain captive insurance arrangements. The Company expects to continue its practice of repatriating available funds from its non-U.S. operating subsidiaries out of current annual earnings. Where appropriate, a portion of the current year earnings will continue to be permanently reinvested.

In 2023, the Company recorded foreign currency translation adjustments which increased net equity by $274 million. Continued weakening of the U.S. dollar against foreign currencies would further increase the translated U.S. dollar value of the Company’s net investments in its non-U.S. subsidiaries, as well as the translated U.S. dollar value of cash repatriations from those subsidiaries.

Cash and cash equivalents on our consolidated balance sheets includes funds available for general corporate purposes. Fiduciary assets are shown separately in the consolidated balance sheets as cash and cash equivalents held in a fiduciary capacity, with a corresponding amount in current liabilities. Fiduciary assets cannot be used for general corporate purposes, and should not be considered as a source of liquidity for the Company.

Operating Cash Flows

The Company provided $4.3 billion of cash from operations in 2023, compared to $3.5 billion provided by operations in 2022. These amounts reflect the net income of the Company during those periods, excluding gains or losses from investments, adjusted for non-cash charges and changes in working capital which relate primarily to the timing of payments of accrued liabilities, including incentive compensation, or receipts of receivables and pension contributions. The Company used cash of $271 million and $193 million related to its restructuring activities in 2023 and 2022, respectively.

Pension Related Items

Contributions

The Company's policy for funding its tax-qualified defined benefit plans is to contribute amounts at least sufficient to meet the funding requirements set forth in accordance with applicable law. In 2023, the Company contributed $33 million to its U.S. defined benefit pension plans and $78 million to its non-U.S. defined benefit pension plans. In 2022, the Company contributed $30 million to its U.S. defined benefit pension plans and $139 million to its non-U.S. defined benefit pension plans.

In the U.S., contributions to the tax-qualified defined benefit plans are based on Employee Retirement Income Security Act ("ERISA") guidelines and the Company generally expects to maintain a funded status of 80% or more of the liability determined in accordance with the ERISA guidelines. In 2023, the Company made contributions of $33 million to its non-qualified plans and expects to contribute approximately $31 million in 2024. The Company was not required to and made no contributions to its U.S. qualified plans in 2023. In 2024, the Company is required to make contributions totaling $2 million to its U.S. qualified plans.

Outside the U.S., the Company has a large number of defined benefit pension plans, the largest of which are in the U.K., which comprise approximately 79% of non-U.S. plan assets at December 31, 2023. Contribution rates for non-U.S. plans are generally based on local funding practices and statutory requirements, which may differ significantly from measurements in accordance with U.S. GAAP.

In the U.K., the assumptions used to determine pension contributions are the result of legally-prescribed negotiations between the Company and the plans' trustee that typically occur every three years in conjunction with the actuarial valuation of the plans. Currently, this results in a lower funded status compared to U.S. GAAP and may result in contributions irrespective of the U.S. GAAP funded status.

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In 2021, the JLT Pension Scheme was merged into the MMC U.K. Pension Fund with a new segregated JLT section created (referred to as the "JLT section").

The Company contributed $42 million to its U.K. plans, including the JLT section, in 2023. The Company's contributions to its U.K. plans, including the JLT section, for 2024 are expected to be approximately $39 million. The Company made deficit contributions of $41 million to the JLT section in 2023, and is expected to make contributions totaling approximately $38 million in 2024.

For the MMC U.K. Pension Fund, excluding the JLT section, an agreement was reached with the trustee in the fourth quarter of 2022, based on the surplus funding position at December 31, 2021. In accordance with the agreement, no deficit funding is required at the earliest until 2026. The funding level will be re-assessed during 2025 as part of the December 31, 2024 actuarial valuation to determine if contributions are required in 2026. In December 2022, the Company renewed its agreement to support annual deficit contributions that may be required by the U.K. operating companies under certain circumstances, up to £450 million (or $576 million) over a seven-year period. This is part of an agreement which gives the Company greater influence over asset allocation and overall investment decisions.

The Company expects to contribute approximately $78 million to its non-U.S. defined benefit plans in 2024, comprising approximately of $39 million to the U.K. plans and $39 million to plans outside of the U.K.

Changes in Funded Status and Expense

The year-over-year change in the funded status of the Company's pension plans is impacted by the difference between actual and assumed results, particularly with regard to return on assets, and changes in the discount rate, as well as the amount of Company contributions, if any. Unrecognized actuarial losses as of December 31, 2023, were approximately $1.3 billion and $3.2 billion for the U.S. plans and non-U.S. plans, respectively, compared with losses of $1.4 billion and $2.6 billion as of December 31, 2022. The decrease in the U.S. is primarily due to greater than expected returns on plan assets. The increase in the non-U.S. plans is primarily due to decreases in the discount rates used to measure plan liabilities, lower than expected returns on plan assets and the impact of foreign exchange. In the past several years, the amount of unamortized losses has been significantly impacted, both positively and negatively, by actual asset performance and changes in discount rates. The discount rate used to measure plan liabilities for the Company's U.S. and U.K. plans decreased in 2023 and increased in 2022 and 2021. An increase in the discount rate decreases the measured plan benefit obligation, resulting in actuarial gains, while a decrease in the discount rate increases the measured plan obligation, resulting in actuarial losses. In 2023, the Company's defined benefit pension plan assets had gains of 9.3% and 4.1% in the U.S. and U.K., respectively, as compared to losses of 18.3% and 29.2% in the U.S. and U.K., respectively, in 2022.

Overall, based on the measurement at December 31, 2023, net benefit credits related to the Company’s defined benefit plans are not expected to be materially different in 2024, compared to 2023, for both the U.S. and non-U.S. plans.

The Company’s accounting policies for its defined benefit pension plans, including the selection of and sensitivity to assumptions, are discussed in Management’s Discussion of Critical Accounting Estimates. For additional information regarding the Company’s retirement plans, refer to Note 1, Summary of Significant Accounting Policies, and Note 8, Retirement Benefits, in the notes to the consolidated financial statements.

Financing Cash Flows

Net cash used for financing activities was $1.1 billion in 2023, compared with $1.0 billion used by financing activities in 2022.

Credit Facilities

In October 2023, the Company increased its multi-currency unsecured five-year revolving credit facility (the "Credit Facility") capacity to $3.5 billion from $2.8 billion and extended the expiration to October 2028. The interest rate on the Credit Facility was initially based on LIBOR plus a fixed margin which varied with the Company's credit rating. In the second quarter of 2023, the Credit Facility was amended that borrowings under the Credit Facility bear interest at a rate per annum equal, at the Company's option, either at (a) SOFR benchmark rate for U.S. dollar borrowings, or (b) a currency specific benchmark rate, plus an applicable margin which varies with the Company's credit ratings. The Company is required to maintain certain coverage and leverage ratios for the Credit Facility, which are evaluated quarterly.

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The Credit Facility includes provisions for determining a benchmark replacement rate in the event existing benchmark rates are no longer available or in certain other circumstances, in which an alternative rate may be required. At December 31, 2023 and 2022, the Company had no borrowings under this facility.

In October 2023, the Company terminated its one-year uncommitted revolving credit facility ("Uncommitted Credit Facility"). There were no borrowings outstanding under the Uncommitted Credit Facility at December 31, 2022.

The Company also maintains other credit and overdraft facilities with various financial institutions aggregating $113 million at December 31, 2023, and $362 million at December 31, 2022. There were no outstanding borrowings under these facilities at December 31, 2023 and 2022.

The Company has outstanding guarantees and letters of credit with various banks aggregating $139 million and $152 million at December 31, 2023 and 2022, respectively.

Debt

In November 2023, the Company increased its short-term commercial paper financing program (the "Program") to $3.5 billion from $2.8 billion. The Company had previously increased the Program's capacity in October 2022 to $2.8 billion from $2.0 billion. The Company did not have any commercial paper outstanding at December 31, 2023 and 2022.

In October 2023, the Company repaid $250 million of 4.05% senior notes that matured.

In September 2023, the Company issued $600 million of 5.400% senior notes due 2033 and $1 billion of 5.700% senior notes due 2053. In March 2023, the Company issued $600 million of 5.450% senior notes due 2053. The Company used the net proceeds from these issuances for general corporate purposes.

In October 2022, the Company issued $500 million of 5.75% senior notes due 2032 and $500 million of 6.25% senior notes due 2052. The Company used the net proceeds from these issuances for general corporate purposes, and repaid $350 million of 3.30% senior notes in November 2022, with an original maturity date of March 2023.

The Company's senior debt is currently rated A- by Standard & Poor's ("S&P"), A3 by Moody's, and A- by Fitch. The Company's short-term debt is currently rated A-2 by S&P, P-2 by Moody's, and F-2 by Fitch. The Company carries a Stable outlook with S&P, Moody's and Fitch.

Share Repurchases

In 2023, the Company repurchased 6.4 million shares of its common stock for $1.15 billion. At December 31, 2023, the Company remained authorized to repurchase up to approximately $3.2 billion in shares of its common stock. There is no time limit on this authorization. In 2022, the Company repurchased 12.2 million shares of its common stock for $1.9 billion.

In March 2022, the Board of Directors of the Company authorized an additional $5 billion in share repurchases. This was in addition to the Company's existing share repurchase program, which had approximately $1.3 billion of remaining authorization at December 31, 2021.

Dividends

The Company paid dividends on its common stock shares of $1.3 billion ($2.60 per share) in 2023, as compared with $1.1 billion ($2.25 per share) in 2022.

In January 2024, the Board of Directors of the Company declared a quarterly dividend of $0.710 per share on outstanding common stock, payable in February 2024.

Contingent Payments Related To Acquisitions

The classification of contingent consideration in the consolidated statements of cash flows is dependent upon whether the receipt, payment or adjustment was part of the initial liability established on the acquisition date (financing) or an adjustment to the acquisition date liability (operating).

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The following amounts are included in the consolidated statements of cash flows as operating and financing activities:

For the Years Ended December 31,
(In millions)	2023		2022		2021
Operating:
Contingent consideration payments for prior year acquisitions	$	(41)	$	(38)	$	(49)
Receipt of contingent consideration for dispositions	1		—		19
Acquisition/disposition related net charges for adjustments	29		49		57
Adjustments and payments related to contingent consideration	$	(11)	$	11	$	27
Financing:
Contingent consideration for prior year acquisitions	$	(135)	$	(32)	$	(28)
Deferred consideration related to prior year acquisitions	(67)		(126)		(89)
Payments of deferred and contingent consideration for acquisitions	$	(202)	$	(158)	$	(117)
Receipt of contingent consideration for dispositions	$	2	$	3	$	71

For acquisitions completed in 2023, and in prior years, remaining estimated future contingent payments of $252 million and deferred consideration payments of $92 million, are recorded in accounts payable and accrued liabilities or other liabilities in the consolidated balance sheets at December 31, 2023.

Derivatives - Net Investment Hedge

The Company has investments in various subsidiaries with Euro functional currencies. As a result, the Company is exposed to the risk of fluctuations between the Euro and U.S. dollar exchange rates. As part of its risk management program, the Company issued €1.1 billion senior notes, and designated the debt instruments as a net investment hedge of its Euro denominated subsidiaries. The hedge is re-assessed each quarter to confirm that the designated equity balance at the beginning of each period continues to equal or exceed 80% of the outstanding balance of the Euro debt instrument and that all the critical terms of the hedging instrument and the hedged net investment continue to match. If the hedge is highly effective, the change in the debt balance related to foreign exchange fluctuations is recorded in accumulated other comprehensive loss in the consolidated balance sheets.

The U.S. dollar value of the Euro notes increased by $54 million in 2023 due to change in foreign exchange rates. The Company concluded that the hedge was highly effective and recorded an increase to accumulated other comprehensive loss for the year ended December 31, 2023.

Purchase of remaining non-controlling interest

In the second quarter of 2023, the Company purchased the remaining interest in a subsidiary for $139 million.

Fiduciary Liabilities

Since fiduciary assets are not available for corporate use, fiduciary assets are shown separately in the consolidated balance sheets as cash and cash equivalents held in a fiduciary capacity, with a corresponding amount in current liabilities. Financing cash flows reflect an increase of $255 million and $1.7 billion in 2023 and 2022, respectively, related to fiduciary liabilities.

Investing Cash Flows

Net cash used for investing activities amounted to $1.4 billion in 2023, compared with $850 million used for investing activities in 2022.

The Company paid $976 million and $572 million, net of cash, cash equivalents and cash and cash equivalents held in a fiduciary capacity acquired, for acquisitions in 2023 and 2022, respectively. The outflow of funds in 2023 related primarily to the acquisitions of Honan Insurance Group, Graham Company and the Westpac Transaction for $358 million, $307 million, and $232 million, respectively.

In connection with the disposition of Mercer's U.S. affinity business in 2022, the Company transferred to the buyer an additional $24 million of cash and cash equivalents held in a fiduciary capacity in 2023.

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In 2022, the Company sold certain businesses, primarily Mercer's U.S. affinity business, for cash proceeds of approximately $155 million, partially offset by $36 million primarily related to cash a