Berkshire's Nucor stake of 6.6 million shares was the biggest new investment worth roughly $857 million at the end of the quarter.

Berkshire Hathaway revealed four new investments Thursday in steelmaker Nucor, insurer UnitedHealth and two of the nation's biggest homebuilders — Lennar and DR Horton — but it's not clear if the ...

UnitedHealth Group soared 11% in after-hours trading Thursday to $300.5, marking its first close above $300 in a month, following regulatory filings that showed Warren Buffett’s Berkshire Hathaway and ...