By Jonathan Stempel
July 8 (Reuters) - Warren Buffett has donated roughly $2.9 billion of Berkshire Hathaway Inc stock to four family charities and the Bill & Melinda Gates Foundation, the latest but not largest contribution in his plan to give away his fortune.
In a statement on Wednesday, Berkshire said Buffett's 15th annual donation comprised 15.97 million Class B shares of Berkshire.
It boosted his donations to the charities to more than $37.4 billion since Buffett, who turns 90 on Aug. 30, began giving his Berkshire shares away in 2006.
Four-fifths of the donations go to the Gates Foundation. The rest goes to the Susan Thompson Buffett Foundation, named for Buffett's late first wife, and charities run by his children Howard, Susan and Peter: the Howard G. Buffett Foundation, the Sherwood Foundation and the NoVo Foundation.
Buffett's largest donation was $3.61 billion in 2019, when Berkshire's stock price was higher.
Though Buffett has donated 48% of his Berkshire shares, he still owns roughly 15.2% of the Omaha, Nebraska-based conglomerate and controls nearly one-third of its voting power.
Forbes magazine said on Tuesday that Buffett was still worth $71.4 billion, ranking seventh worldwide.
Amazon.com Inc founder Jeff Bezos ranked first at $178.1 billion, while Microsoft Corp co-founder Bill Gates was second.
Gates, a longtime Buffett friend, ended his 16-year run on Berkshire's board this year to focus on his foundation.
Berkshire stock has significantly lagged broader markets in 2019 and 2020.
This is in part because Buffett has not found attractive major acquisitions and financing opportunities for his $440 billion conglomerate, even during the novel coronavirus pandemic.
Berkshire owns more than 90 businesses such as BNSF railroad, Geico auto insurance and Dairy Queen ice cream.
It also owns dozens of stocks, including more than $93 billion of Apple Inc based on regulatory filings. (Reporting by Jonathan Stempel in New York)