UnitedHealth Group Inc. had been pretty much abandoned by Wall Street, but it was the stock of the day on Friday after Warren Buffett said it was time to start buying into the health insurer.

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.

The Dow Jones Industrial Average and S&P 500 rose to new record highs Friday, as the Dow benefited from UnitedHealth Group’s stock pacing its largest single-day gain in nearly five years in the wake o...

The S&P 500 rose 8.8 points, or 0.14%, to 6,477.38​, while the Nasdaq Composite dropped 1.3 points, or 0.01%, to 21,709.336.