The Kahn Brothers have operated their namesake hedge fund, Kahn Brothers Group, since 1978. Irving Kahn studied under Benjamin Graham and earned his M.B.A. from Columbia University. Thomas G. Kahn received his M.B.A. from New York University. Their website quotes Benjamin Graham, whose protégé, Warren Buffett, was inspired by Graham's value-based approach: “An investment operation is one which, upon thorough analysis promises safety of principal and an adequate return. Operations not meeting these requirements are speculative.” So goes the Kahn Brothers' investment methodology, which focuses on book value, historic P/E, management quality, and market inefficiencies to gauge the quality of investments.