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 Berkshire Hathaway shareholders meeting draws thousands of loyal fans who are investors.

Quarterly filed Form 13Fs provide a way for investors to track the buying and selling activity of Wall Street's top money managers. Warren Buffett is occasionally granted the "confidential treatment" tag,

Shares of some of UnitedHealth’s peers got a bump in the wake of Berkshire’s investment in the healthcare giant, and they all look cheaper based on price relative to expected earnings.