By Jonathan Stempel
(Reuters) - Warren Buffett, the billionaire chairman of Berkshire Hathaway Inc, has donated another roughly $2.86 billion of his holdings in the company's stock to the Bill & Melinda Gates Foundation and four family charities, as part of his plan to give away nearly his entire fortune.
Buffett's 11th annual donation to the five charities comprised 19.61 million Class "B" shares of Berkshire, according to a regulatory filing on Thursday.
The Gates Foundation, which focuses on improving education and health and reducing poverty, received about 14.96 million shares.
The donations were made on Wednesday, and brought Buffett's total contributions to the charities to more than $24.3 billion since 2006.
Also receiving donations were the Susan Thompson Buffett Foundation, named for Buffett's late first wife, and the Howard G. Buffett, Sherwood and NoVo Foundations, respectively overseen by his children Howard, Susan and Peter.
Buffett, 85, remains the world's third-richest person, according to Forbes magazine.
Buffett still owns about 18 percent of Berkshire's stock, down from 32.3 percent before the donations began in 2006. He controls about 31.7 percent of the Omaha, Nebraska-based conglomerate's voting power.
Before the donations were announced, Forbes estimated Buffett's net worth at $68.4 billion, trailing Bill Gates' $77.6 billion and Spanish retailing magnate Amancio Ortega's $74 billion. Amazon.com Inc founder Jeff Bezos followed Buffett, at $64.3 million.
Gates, the co-founder of Microsoft Corp, has known Buffett for a quarter century and counts him as a close friend. He is also a Berkshire director.
Buffett typically makes his donations in July, reducing the number of shares by 5 percent from the prior year.
The charities usually sell the Berkshire shares to finance their activities, reflecting Buffett's desire that his money be spent. Buffett also makes smaller donations to other charities.
Berkshire has roughly 90 subsidiaries including Geico car insurance, the BNSF railroad and Dairy Queen ice cream, and has large stakes in companies such as Kraft Heinz Co, Wells Fargo & Co, Coca-Cola Co and IBM Corp.
Buffett has run Berkshire since 1965.
(Reporting by Jonathan Stempel in New York; Editing by Jonathan Oatis and Leslie Adler)