Berkshire purchases often boost stocks. Shares of the steel maker were rising 6% on Friday to $153 a share, while S&P 500 and Dow Jones Industrial Average futures were up 0.2% and 0.7%, respectively. Berkshire, of course, has an incredible investing pedigree. Buying the shares is a big vote of confidence in Nucor.

Warren Buffett’s Berkshire Hathaway revealed a position in embattled healthcare giant UnitedHealth Group while showing smaller stakes in longtime holdings Apple and Bank of America, according to a regulatory filing Thursday.

The Omaha-based conglomerate bought more than 5 million shares in the healthcare firm for a stake worth about $1.6 billion at the end of June.