While the "vote of confidence" from Buffett's investment validates the long-term value of UnitedHealth shares, the "management needs to regain trust and credibility with investors, and get back to its beat and raise reputation of the past," said James Harlow, senior vice president at Novare Capital Management.

Berkshire Hathaway revealed three new investments Thursday in steelmaker Nucor and two of the nation’s biggest homebuilders — Lennar and DR Horton — but none of the investments are big enough to ensu...

The stake was valued at about $1.57 billion.