UnitedHealth Group Inc. (NYSE:UNH) extended its rebound Monday, climbing another 3% in premarket trading after soaring 12% on Friday. The surge followed revelations that Warren Buffett’s Berkshire ...

If any investor has stood the test of time, it is Warren Buffett, and with good reason. For years, the “Oracle of Omaha” has had a rock-star-like presence in the investing world, and his annual ...