Warren Buffett donates about $870 million to four of his family foundations

Billionaire Warren Buffett donated about $870 million in Berkshire Hathaway Inc. stock to four family charities Tuesday, saying he has “much to be thankful for” this Thanksgiving.

In a statement, the Berkshire chief executive said he converted 1,600 Class A shares BRK.A into 2.4 million Class B shares BRK.B, and spread those Class B shares to four of his family foundations: 1.5 million shares went to the Susan Thompson Buffett Foundation, named for his late first wife, while 300,000 shares apiece went to the Sherwood Foundation,…