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So while we should always try to assess where a stock or sector is headed, the better way to trade is with a simple framework: Any stock can go up and thus be a source of profits. However, owning each stock comes with different levels of risk,

Berkshire Hathaway's latest regulatory filing revealed that the company took a considerable stake in UnitedHealth. The 5 million-share, $1.6 billion stake makes the massive health insurer the 18th-biggest position in Berkshire's portfolio. Buffett's company also trimmed its positions in Apple and Bank of America.