Berkshire Hathaway (GEICO + General Re)

Berkshire Hathaway amasses $82B in P&C premiums, powered by GEICO's 15% market share in auto insurance and General Re's global reinsurance. Warren Buffett acquired GEICO in 1996 for $2.3B—a deal now worth hundreds of billions—showcasing 60% compound annual growth. This combination of direct and reinsurance strength outperforms #3 Progressive and #4 Allstate in underwriting profitability.