The biggest immediate changes will be that different people will be in control of the company's stock portfolio, and Abel will have power over Berkshire's $344 billion cash hoard. However, portfolio managers Ted Weschler and Todd Combs have been managing more of Berkshire's investments as the years have progressed.

Warren Buffett's Berkshire Hathaway is secretly building a substantial position, estimated at nearly $5 billion, sparking widespread speculation. CNBC

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Leveraged positions in the stock market jumped 18% in one month and topped $1 trillion for the first time. Increasing use of debt to invest can tell us a lot about investors' attitudes. And while this has always been the case,

Buffett owned UnitedHealth shares before selling his stake in 2010, though his Berkshire Hathaway recently acquired shares.

UNH stock soared after Warren Buffett’s Berkshire Hathaway revealed it bought shares of the healthcare company. Nonetheless, UnitedHealth faces a long list of unresolved issues.

Warren Buffett has authorized $77.8 billion worth of stock buybacks since 2018, double the amount he has ever invested in any other stock. While Berkshire's buyback program remains active, Buffett hasn't pulled the trigger in any of the past four quarters.