Subject: UNH
"(Reuters) -Warren Buffett's Berkshire Hathaway has acquired 5 million shares in UnitedHealth Group, a regulatory filing showed on Thursday, sending the health insurer's stock up 7% in extended trading.

Billionaire investor Buffett owned about 1.18 million shares in UnitedHealth between 2006 and 2009, before selling his entire stake in 2010 amid a broader retreat from health insurers."