The equity commitment comes in the wake of the Gateses' divorce announcement in May and questions surrounding the future leadership of the Gates Foundation. Berkshire Hathaway CEO Warren Buffett announced last week that he was resigning as a trustee and questions have been swirling about the the foundation, which has an endowment worth nearly $50 billion and has issued close to $55 billion in grants since launching in 2000. Suzman said in an email to employees after Buffett's announcement that the departure does raise questions about the foundation's governance.