Berkshire Hathaway bought Nucor stock. Hopefully, this purchase works out better than the last time Warren Buffett dabbled in the steel business. Shares of the steel maker were up 6.4% in early trading Friday at $153.65 a share, while S&P 500 and Dow Jones Industrial futures were each falling 0.1%.

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 biggest immediate changes will be that different people will be in control of the company's stock portfolio, and Abel will have power over Berkshire's $344 billion cash hoard. However, portfolio managers Ted Weschler and Todd Combs have been managing more of Berkshire's investments as the years have progressed.