John Doyle

John Doyle became president and CEO of Marsh McLennan in 2023, leading the world's largest insurance broker and professional services firm. Marsh McLennan operates four globally recognized brands: Marsh (the world's largest insurance and risk management broker), Guy Carpenter (a leading reinsurance broker), Mercer (HR consulting, retirement, investments, and health benefits), and Oliver Wyman (management consulting specializing in financial services). Combined, these businesses generate over $23 billion in annual revenue. As an insurance broker, Marsh sits between insurance buyers (corporations, governments) and insurers, advising on risk management and placing insurance coverage. This intermediary position is enormously powerful: brokers earn commissions from insurers while providing essential advisory services to clients, creating a business with high margins, high recurring revenue, and limited capital requirements. The increasing complexity of global risks — from climate change to cyber threats to geopolitical disruption — drives demand for Marsh McLennan's advisory and broking services. Doyle's execution on organic revenue growth across all four businesses, M&A (Marsh McLennan has been an active acquirer), and margin expansion are the primary drivers of the stock.