Warren Buffett resisted a last-gasp shopping spree in his final weeks as Berkshire Hathaway CEO

Warren Buffett built his fortune through long-term investing at his firm, Berkshire Hathaway.

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• Warren Buffett held tight to the purse strings in his final quarter as Berkshire Hathaway CEO.
• Berkshire's cash pile grew to a record $373 billion as it sold stocks and refrained from buybacks.
• Operating profits fell sharply as insurance weakness outweighed strength in other Berkshire units.

If you handed most people nearly $400 billion...