Arthur J. Gallagher & Co. (AJG) Business

Item 1. Business.

Overview

Arthur J. Gallagher & Co. and its subsidiaries, collectively referred to herein as we, our, us or Gallagher, are engaged in providing insurance brokerage, reinsurance brokerage, consulting, and third-party property/casualty claims settlement and administration services to entities and individuals around the world. We believe that our major strength is our ability to deliver comprehensively structured insurance, reinsurance and risk management solutions, superior claim outcomes and comprehensive consulting services to our clients.

Our brokerage segment operations provide brokerage and consulting services to entities of all types, including commercial, nonprofit, public sector entities, insurance companies and insurance capital providers, and to a lesser extent, individuals, in the areas of insurance and reinsurance placements, risk of loss management, and management of employer sponsored benefit programs. Our risk management segment operations provide contract claim settlement, claim administration, loss control services and risk management consulting for commercial, nonprofit, captive and public sector entities, and various other organizations that choose to self-insure property/casualty coverages or choose to use a third-party claims management organization rather than the claim services provided by an underwriting enterprise.

We do not assume underwriting risk on a net basis, other than with respect to de minimis amounts necessary to provide minimum or regulatory capital to organize captives, pools, specialized underwriters or risk-retention groups. Rather, capital necessary for covering events of loss is provided by “underwriting enterprises,” which we define as insurance companies, reinsurance companies and various other risk-taking entities, including intermediaries of underwriting enterprises, that we do not own or control.

Since our founding in 1927, we have grown from a one-person insurance agency to the world’s third largest insurance broker/risk manager based on revenues according to Business Insurance magazine’s June/July 2025 edition, and one of the world’s largest property/casualty third party claims administrators, according to Business Insurance magazine’s April/May 2025 edition.

We report our results in three segments: brokerage, risk management and corporate. The brokerage and risk management segments contributed approximately 87% and 13%, respectively, to 2025 revenues. We generate approximately 67% of our revenues from the combined brokerage and risk management segments in the U.S., with the remaining 33% generated internationally, primarily in Australia, Canada, New Zealand and the U.K. The corporate segment did not generate any significant revenues in 2025.

Shares of our common stock are traded on the New York Stock Exchange under the symbol “AJG”, and we had a market capitalization at December 31, 2025 of approximately $67 billion. Information in this report is as of December 31, 2025 unless otherwise noted. We were reincorporated as a Delaware corporation in 1972. Our executive offices are located at 2850 Golf Road, Rolling Meadows, Illinois 60008-4050, and our telephone number is (630) 773‑3800.

Operating Segments

We report our results in three segments: brokerage, risk management and corporate. The major sources of our operating revenues are commissions, fees, supplemental and contingent revenues and interest income, premium finance and other income from our brokerage operation, and fees, including performance‑based fees, from our risk management operations. The corporate segment does not generate any significant revenues.

Our business, particularly our brokerage business, is subject to seasonal fluctuations. Commissions, fees, supplemental revenues and contingent revenues, and our costs to obtain and fulfill the service obligations to our clients, can vary from quarter to quarter as a result of the timing of contract-effective dates. On the other hand, salaries and employee benefits, rent, depreciation and amortization expenses generally tend to be more uniform throughout the year. The timing of acquisitions, recognition of books of business gains and losses also impact the trends in our quarterly operating results.

Brokerage Segment

The brokerage segment accounted for 87% of our revenues in 2025. Our brokerage segment operates through a network of more than 650 sales and service offices located throughout the U.S. and approximately 400 sales and service offices in

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approximately 60 countries, most of which are in the Australia, Canada, New Zealand and the U.K. Most of these offices are fully staffed with sales and service personnel. We offer client service capabilities in approximately 130 countries around the world through our direct operations as well as through a network of correspondent brokers and consultants.

Domestic Retail Insurance Brokerage Operations

Our retail insurance brokerage operations accounted for 75% of our brokerage segment revenues in 2025. Our retail brokerage operations place nearly all lines of commercial property/casualty and health and welfare insurance coverage. Significant lines of insurance coverage and consultant capabilities are as follows:

Our retail brokerage operations are organized and operate within certain key niche/practice groups, which account for approximately 74% of our retail brokerage revenues. These specialized teams target areas of business and/or industries in which we have developed a depth of expertise and a large client base. Significant niche/practice groups we serve are as follows:

Our specialized focus on these niche/practice groups allows for highly-focused marketing efforts and facilitates the development of value-added products and services specific to those industries. We believe that our detailed understanding and broad client contacts within these niche/practice groups provide us with a competitive advantage.

We anticipate that our retail brokerage operations’ greatest revenue growth over the next several years will continue to come from:

•Our niche/practice groups and middle-market accounts;

•Cross-selling other brokerage products to existing clients;

•Mergers and acquisitions; and

•Developing and managing alternative market mechanisms such as captives, rent-a-captives and deductible plans/self‑insurance.

International and Other Brokerage Related Operations

We operate as a retail commercial property and casualty broker throughout 47 locations in Australia, 40 locations in Canada and 37 locations in New Zealand. In the U.K., we operate as a retail broker from approximately 128 locations. We also have specialty, wholesale, underwriting and reinsurance intermediary operations in London for clients to access Lloyd’s of London and other international underwriting enterprises, and a program operation offering customized risk

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management products and services to U.K. public entities. See the discussion below regarding our “Global Reinsurance Brokerage Operations.”

In Bermuda, we act principally as a wholesale broker for clients looking to access Bermuda-based underwriting enterprises and we also provide management and administrative services for captive insurance entities.

We also have strategic brokerage alliances with a variety of independent brokers in countries where we do not have a local office presence. Between our direct operations and this global network of correspondent insurance brokers and consultants, we are able to serve our clients’ coverage and service needs in approximately 130 countries around the world.

Global Reinsurance Brokerage Operations

Our reinsurance brokerage operations (which we refer to as Gallagher Re) accounted for 12% of our brokerage segment revenues in 2025. Gallagher Re operates from more than 77 offices across 27 countries, with specialist expertise, underpinned by a portfolio of analytics capabilities including catastrophe modeling, dynamic financial analysis, rating agency analysis and capital modeling. Our reinsurance brokers assist underwriting enterprises, such as insurance companies and managing general underwriters, to secure protection or reinsurance from another insurance company for a specific risk or class of risks, including negotiating rates and terms and while sourcing the best-suited contracts available on the market. Additionally, through Gallagher Securities, Gallagher Re provides capital markets services, including acting as underwriter, with respect to insurance‑linked securities, weather derivatives, capital raising and selected merger and acquisition advisory activities. We anticipate growing Gallagher Re by increasing the number of underwriting enterprise clients, deepening our relationships with current underwriting enterprise clients, developing new products, further building out our facultative capabilities, and through mergers and acquisitions.

Wholesale Insurance Brokerage Operations

Our wholesale insurance brokerage operations accounted for 13% of our brokerage segment revenues in 2025. Our wholesale brokers assist our retail brokers and other non-affiliated brokers in the placement of specialized and hard-to-place insurance. These brokers operate through approximately 149 offices primarily located across the U.S., Bermuda and through our approved Lloyd’s of London brokerage operation. More than 75% of our wholesale brokerage revenues comes from non-affiliated brokerage clients.

In certain cases we act as a brokerage wholesaler, and in other cases we act as a managing general agent or managing general underwriter, distributing specialized insurance coverages for underwriting enterprises. Managing general agents and managing general underwriters are agents authorized by an underwriting enterprise to manage all or a part of its business in a specific geographic territory. Activities they perform on behalf of the underwriting enterprise may include marketing, underwriting (although we do not assume any underwriting risk), issuing policies, collecting premiums, appointing and supervising other agents, paying claims and negotiating reinsurance.

We believe our growth prospects for our wholesale brokerage operations depend on increasing the number of broker-clients, developing new managing general agency and underwriter programs, and through mergers and acquisitions.

Captive Underwriting Enterprises

We have ownership interests in several underwriting enterprises based in the U.S., Bermuda, Gibraltar, Guernsey and Isle of Man that primarily operate segregated account “rent-a-captive” facilities. These “rent-a-captive” facilities enable our clients to receive the benefits of participating in a captive underwriting enterprise without incurring certain disadvantages of ownership. In Malta and Ireland, we act as managers of underwriting enterprises.

We also have a wholly owned underwriting enterprise subsidiary based in the U.S. that cedes all of its insurance risk of loss to reinsurers or captives under facultative and quota-share treaty reinsurance agreements.

Risk Management Segment

Our risk management segment accounted for 13% of our revenues in 2025. Approximately 59% of our risk management segment’s revenues are from workers’ compensation-related claims, 34% are from general and commercial auto liability-related claims and 7% are from property-related claims in 2025.

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Risk management services are primarily marketed on an independent basis from our brokerage operations, to Fortune 1000 companies, larger middle-market companies, nonprofit organizations, public sector entities, and underwriting enterprises, such as insurance carriers and captives. We manage our third party claims adjusting operations through a network of more than 40 offices located throughout Australia, Canada, New Zealand, the U.K. and the U.S. Most of these offices are fully staffed with claims adjusters and other service personnel. Our adjusters and service personnel act solely on behalf and under the instruction of our clients.

While this segment complements our brokerage offerings, approximately 95% of our risk management segment’s revenues come from clients not affiliated with our brokerage operations, such as underwriting enterprises and clients of other insurance brokers.

We expect that the risk management segment’s most significant growth prospects through the next several years will come from:

•Program business and the outsourcing of portions of underwriting enterprise claims departments;

•Increased levels of business with Fortune 1000 companies;

•Larger middle-market companies and captives; and

•Mergers and acquisitions.

Corporate Segment

The corporate segment reports the financial information related to our debt, external acquisition-related expenses, other corporate costs, the impact of foreign currency remeasurement and clean energy investments. As a result, the timing of acquisitions impact the trends in our quarterly operating results.

Competition

Brokerage Segment

The insurance and reinsurance brokerage and consulting businesses are highly competitive and there are many organizations and individuals throughout the world who actively compete with us in every area of our business. Additionally, we also face competition from insurance and reinsurance carriers that market, distribute and service a portion of their products directly, and in some cases from banks, consulting and accounting firms, and technology companies that can provide alternative risk management products or services.

We believe that the primary factors determining our competitive position with other organizations in our industry are the quality of the services we offer, the personalized attention we provide, the individual and corporate expertise providing the actual service to the client, the data analytics and technology capabilities we have built, the overall cost efficiencies we create for our clients, and our ability to address client needs across the insurance value chain by leveraging our capabilities in insurance, reinsurance, alternative risk transfer, management and administrative services, benefits consulting and claims management. We provide sophisticated data analysis and other data and benchmarking insights through a product offering we refer to as Gallagher Drive to help our clients make insurance decisions. Through our SmartMarket platform, we also provide insurance carriers with individualized preference setting and risk identification capabilities, as well as performance data and metrics. We believe these capabilities provide a growing competitive advantage with respect to many of the smaller organizations with which we compete.

Risk Management Segment

Our risk management business competes with a number of companies varying in size and scope, including global independent third party claims administrators, regional third party claims administrators, insurance owned claims administrators and legal firms in certain jurisdictions. We believe that the primary factors determining our competitive position are our ability to deliver better outcomes, reputation for outstanding service, cost-efficient service, our data analytics capabilities and financial strength.

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Business Combinations

We completed approximately 780 acquisitions from January 1, 2002 through December 31, 2025. The majority of these acquisitions have been smaller regional or local brokerages, agencies, or employee benefit consulting operations with a middle or small client focus and/or significant expertise in one of our niche/practice groups. The total purchase price for individual acquisitions has typically ranged from $1 million to $100 million. During 2025, we also completed several acquisitions that were larger than our usual tuck-in acquisitions, namely the acquisitions of Woodruff Sawyer and AssuredPartners, within our brokerage segment.

Through these acquisitions, we seek to expand our talent pool, enhance our geographic presence and service capabilities, or further diversify our business mix. We also focus on identifying:

•A corporate culture that matches our sales-oriented and ethics-based culture;

•A profitable, growing business whose ability to compete would be enhanced by gaining access to our greater resources; and

•Clearly defined financial criteria.

See Note 3 to our 2025 consolidated financial statements for a summary of our 2025 acquisitions, the amount and form of the consideration paid and the dates of acquisitions.

Clients

Our client base is highly diversified and includes commercial, industrial, public sector, religious and nonprofit entities, as well as underwriting enterprises in our reinsurance operations and risk management segment. In 2025, our largest single client represented approximately 1% and our ten largest clients together represented approximately 3%, respectively, of our combined brokerage and risk management segment revenues.

Human Capital

As of December 31, 2025, we had approximately 72,000 employees, with approximately 47% in the U.S. and 53% outside of the U.S. Approximately 77% of our employees work in our brokerage segment and 15% in our risk management segment. Our remaining employees work in our corporate segment, primarily at our headquarters and at Gallagher Centers of Excellence in India. In 2025, our total compensation expense was $6,660 million for the brokerage segment and $974 million for the risk management segment, representing 55% and 61%, respectively, of brokerage and risk management segment revenues. Additional information regarding compensation expense, both on a reported and an adjusted basis can be found elsewhere in this report under Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

Talent Development and Retention

While many of our new employees come to us through mergers and acquisitions and traditional hiring, “growing our own” has long been a key part of our human capital strategy. The Gallagher North American Sales Internship Program has been a key part of our talent development strategy for 60 years. During that time, our program has grown globally and we employed approximately 500 interns in the summer of 2025. We provide our interns with professional development and on‑the‑job sales training that gives them the opportunity to cultivate expertise and accelerate their full-time sales career growth.

We invest in our employees and aim to offer competitive compensation and benefits packages. We acknowledge the changing work landscape and promote hybrid work arrangements, aiming to provide our employees with flexibility and work-life balance. Further, we conduct periodic global engagement surveys that have had increasingly strong participation and positive results. We aim to foster an environment that values and leverages the talents, perspectives and ideas of all employees so they can reach their fullest potential. As of December 31, 2025, approximately 58% of our employees were women, including 50% of managers and 39% of producers. In the U.S., approximately 26% of our employees were racially/ethnically diverse, including 18% of managers and 20% of producers.

Employee Learning and Development

We have programs around the world that offer learning and development opportunities to our employees. For example, the Achieve and Gallagher Career Associate Programs are career development programs available in North America that combine formal training, with experiential learning to provide participants the knowledge needed to be successful

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as client service and sales professionals, respectively. Similarly, we offer development programs outside the U.S., for example in Australia, Canada, India, New Zealand and the U.K. In addition, we provide on‑demand access to over 35,000 globally accessible business skills training modules across 18 languages.

Regulation

Many of our activities throughout the world, such as our insurance brokerage, securities broker‑dealer and investment advisory services, are subject to supervision and regulations promulgated by regulatory or self‑regulatory bodies such as the SEC, the NYSE, the U.S. Department of Justice (which we refer to as the DOJ), the IRS, the Federal Trade Commission (which we refer to as the FTC) the Financial Industry Regulatory Authority (which we refer to as the FINRA) and the Financial Crimes Enforcement Network in the U.S., the Financial Conduct Authority in the U.K. (which we refer to as the FCA) in the U.K., the Australian Securities and Investments Commission in Australia and insurance regulators in nearly every jurisdiction in which we operate. Our retirement-related consulting and investment advisory services are subject to pension law and financial regulation in many countries. Our activities are also subject to a variety of other laws, rules and regulations addressing, licensing, cybersecurity, data privacy, AI, wage-and-hour standards, employment and labor relations, competition, anti-corruption, currency, the conduct of business, reserves and the amount of local investment with respect to our operations in certain countries. For example, the DOJ updated its guidance on corporate compliance programs to include AI risk management.

The global nature of our operations increases the complexity and cost of compliance with laws and regulations, including increased staffing needs, the development of new policies, procedures and internal controls and providing training to employees in multiple locations, adding to our cost of doing business. Many of these laws and regulations may have differing or conflicting legal standards across jurisdictions, increasing further the complexity and cost of compliance. We experience substantial geopolitical and regulatory changes on a real-time basis, which may lead to uncertainty and increase the complexity, difficulty, and cost of compliance. In emerging markets and other jurisdictions with less developed legal systems, local laws and regulations may not be established with sufficiently clear and reliable guidance to provide us with adequate assurance that we are aware of all necessary licenses to operate our business, that we are operating our business in a compliant manner, or that our rights are otherwise protected. In addition, major political and legal developments in jurisdictions in which we do business may lead to new regulatory costs and challenges. For example, China has in place a “blocking” statute similar to that of the European Union (which we refer to as the E.U.) requiring compliance with certain Chinese laws if they conflict with U.S. laws. Rising global tensions and protectionism may also lead other countries to adopt similar blocking statutes, which could make it more difficult and costly for us to expand our operations globally.

In addition, climate change and sustainability issues remain a significant focus for investors, clients and other business partners, while regulatory approaches across jurisdictions continue to vary widely. Some jurisdictions, such as the U.K, Australia and the State of California, are intensifying regulation and enforcement with respect to climate-related disclosures, where others are moving towards deregulation – for example, at the U.S. federal level the SEC abandoned the defense of the climate-related disclosures rule and the E.U. approved the Omnibus I directive that reduced significantly the entities subject to, and the requirements of, the Corporate Sustainability Reporting Directive (which we refer to as CSRD) and the Corporate Sustainability Due Diligence Directive (which we refer to as CSDDD). Navigating these inconsistent and evolving rules may demand substantial effort and resources.

Available Information

Our executive offices are located at 2850 Golf Road, Rolling Meadows, Illinois 60008-4050, and our telephone number is (630) 773‑3800. Our annual reports on Form 10-K, quarterly reports on Form 10‑Q, current reports on Form 8‑K, and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act, are available free of charge on our website at http://investor.ajg.com/sec-filings as soon as reasonably practicable after electronically filing or furnishing such material to the SEC. The SEC also maintains a website (www.sec.gov) that includes our reports, proxy statements and other information. Unless expressly noted, the information on our website, including our investor relations website, or any other website is not incorporated by reference in this Form 10-K and should not be considered part of this Form 10-K or any other filing we make with the SEC.