In June 2006, Warren Buffett pledged the bulk of his fortune to charity, with the largest share — about 10 million Berkshire Hathaway Class B shares then worth roughly $31 billion — going to the Bill & Melinda Gates Foundation, to be paid out gradually in annual installments. The gift, among the largest acts of philanthropy in history, effectively doubled the foundation's grant-making capacity and cemented the Gates–Buffett partnership; Buffett joined as a foundation trustee. By the 2020s he had given tens of billions to the foundation under the pledge, though he later directed that it would receive nothing from his estate after his death, with his remaining wealth going to a charitable trust overseen by his children.