Bill Ackman's Pershing Square fund has taken a major new position in Microsoft (NasdaqGS:MSFT), going public with the stake as other large investors such as TCI and the Gates Foundation have been reducing their holdings. The move comes as Microsoft ramps up its AI efforts beyond OpenAI, including interest in larger AI startup acquisitions, an expanded partnership with OneStream in enterprise finance, and visible traction for new AI products. Ackman cites Azure, Microsoft 365, evolving AI...