Warren Buffett's Berkshire Hathaway increased its holdings in UnitedHealth Group stock, and also added positions in D.R. Horton, Lamar Advertising, and Nucor.

UnitedHealth Got a Boost From Berkshire’s Buying. 2 Reasons to Wait to Follow. UnitedHealth Group, the worst-performing stock in the Dow Jones Industrial Average so far this year, got a major boost last week from billionaire investor Warren Buffett. That doesn’t mean everyone else should buy.

Shares of UnitedHealth Group are surging before the market open Friday as Warren Buffett’s Berkshire Hathaway disclosed that it recently purchased shares of the beleaguered insurer