Marsh & McLennan Companies, Inc.

Is Marsh the same company as Marsh & McLennan?
Yes. Marsh & McLennan Companies, Inc. remains the legal name, but the company rebranded to Marsh effective January 2026. Its New York Stock Exchange ticker changed from MMC to MRSH on January 14, 2026. The four businesses, Marsh, Guy Carpenter, Mercer, and Oliver Wyman, will transition to the Marsh masterbrand by 2027.

Is Marsh publicly traded?
Yes. Marsh & McLennan Companies, Inc. trades on the New York Stock Exchange under the ticker MRSH. It is an S&P 500 component with a market capitalization above $100 billion.

When was Marsh founded?
The company was founded in 1905 in Chicago as Burroughs, Marsh & McLennan by Henry W. Marsh, Donald R. McLennan, and Daniel W. Burroughs. It was renamed Marsh & McLennan in 1906. Henry Marsh's own insurance business dated to 1871.

Who founded Marsh & McLennan?
Henry W. Marsh and Donald R. McLennan founded the firm with Daniel W. Burroughs in 1905. Marsh and McLennan pioneered the concept of the broker acting as a buyer of insurance on behalf of the client rather than a seller for the insurance company.

What is Marsh's market position?
Marsh is the world's largest insurance broker by revenue, generating $27.0 billion in 2025. It outranks Aon, Arthur J. Gallagher, and Willis Towers Watson. Its Guy Carpenter unit is a leading reinsurance broker, and Oliver Wyman is a major management consultancy.

What happened to Marsh McLennan Agency?
Marsh McLennan Agency continues to operate as the company's middle-market insurance agency business in North America. It acquired McGriff Insurance Services for $7.75 billion in November 2024, significantly expanding its scale in commercial property and casualty, employee benefits, and personal lines.

Has Marsh faced any controversies?
The most significant was the 2004 bid-rigging investigation by the New York Attorney General, which resulted in an $850 million settlement, the end of contingent commissions, and a change of CEO. The current Thrive restructuring program has also drawn scrutiny for associated workforce reductions.

The company's roots extend to 1871, when Henry W. Marsh established an insurance business in New York after watching insurers collapse following the Great Chicago Fire. In 1905, Marsh joined with Donald R. McLennan and Daniel W. Burroughs to form Burroughs, Marsh & McLennan in Chicago. Burroughs retired the following year and the firm was renamed Marsh & McLennan.

Marsh and McLennan pioneered a new model: the broker as a buyer of insurance acting on behalf of the client, rather than as a seller working for the insurance company. The firm also helped establish the concept of professional risk management. By 1917 it had offices across the United States. In 1923, the firm made its first major acquisition, absorbing Guy Carpenter & Company, the reinsurance specialist founded in 1922 by the man known as the father of modern reinsurance.

Marsh & McLennan incorporated in 1923 and went public in 1962. It entered the consulting business with the 1959 acquisition of William M. Mercer, an actuarial and benefits consulting firm founded in Vancouver in 1945. Through the 1980s and 1990s the company added consulting capabilities including Temple, Barker & Sloane, Strategic Planning Associates, National Economic Research Associates (NERA), and Lippincott and Margulies, grouping them under the Mercer Consulting Group.

In 2003, the company acquired Oliver, Wyman & Company, a boutique strategy consultancy founded in 1984, and merged it with Mercer Management Consulting and Mercer Delta. The combined consulting unit was unified under the Oliver Wyman name in 2007, with NERA Economic Consulting and Lippincott forming the Oliver Wyman Group.

The company faced a severe crisis in 2004 when New York Attorney General Eliot Spitzer charged Marsh with bid rigging and contingent commission abuses. Marsh paid $850 million to settle, restated its compensation model, and replaced senior leadership. The broader industry changed permanently as a result. In 2010, MMC sold Kroll, the risk consulting firm it had acquired in 2004, refocusing on brokerage and consulting.

Under CEO Dan Glaser (2013 to 2022), the company expanded through disciplined acquisitions and steady margin improvement. John Doyle, previously president of Marsh, became President and CEO in January 2023. In November 2024, the company completed its largest-ever acquisition, purchasing McGriff Insurance Services for $7.75 billion in cash through Marsh McLennan Agency.

In October 2025, the company announced it would rebrand as Marsh effective January 2026 and created a new unit, Business and Client Services, to centralize investment in data, artificial intelligence, analytics, and operational excellence. The company also announced its Thrive program, a multi-year initiative aimed at accelerating growth. Beginning in 2027, Marsh and Mercer will each go to market under the Marsh brand, Guy Carpenter will become Marsh Re, and Oliver Wyman will market itself as Oliver Wyman, a Marsh business.

As a professional services firm, Marsh's direct environmental footprint is modest relative to industrial companies. The company has committed to science-based emissions targets and reports progress in its annual ESG disclosures. It advises clients on climate risk and energy transition through Marsh's specialty practices and Marsh McLennan research platforms.

Marsh is not a certified B Corporation. Its most relevant ethics record concerns the 2004 contingent commission scandal and subsequent industry reforms, detailed in the following section.

The defining controversy in the company's history is the 2004 bid-rigging investigation led by New York Attorney General Eliot Spitzer. Regulators alleged that Marsh steered clients to insurers in exchange for contingent commissions, a practice known as market service agreements. Marsh settled for $850 million without admitting wrongdoing, abolished contingent commissions, and replaced CEO Jeffrey Greenberg. The settlement reshaped broker compensation disclosure across the industry.

The company has faced periodic regulatory scrutiny typical of a global broker, including antitrust inquiries into industry consolidation. The $7.75 billion McGriff acquisition required antitrust review before closing in November 2024.

The October 2025 rebrand and associated reorganization, including the creation of Business and Client Services, involve workforce restructuring under the Thrive program. The company disclosed noteworthy items related to severance and restructuring costs in its 2025 and 2026 results.