This comes as Berkshire's cash pile surged to a record in the first quarter, as Buffett has recently complained about the lack of meaningful deals.

Berkshire Hathaway began purchasing shares in late 2011 when they were around the $6 handle and has long been Bank of America's top shareholder. However, Buffett is now taking a profit, selling about 71.2 million shares this month over the $40 handle. 

According to Bloomberg, Berkshire's stake has been reduced by 6.9% this month alone. However, it still holds nearly 962 million shares, worth around $39.5 billion at Monday's closing price. 

Berkshire was a large buyer of BofA during mid-2020 Covid turmoil. Before that, Buffett invested $5 billion into the Charlotte, North Carolina-based bank in late 2011, when the company faced massive legal liabilities after the 2008 GFC. 

In early May, Buffett told investors at Berkshire's annual meeting that "it's a fair assumption" that the company's cash pile would soon reach $200 billion. 

"We'd love to spend it, but we won't spend it unless we think we're doing something that has very little risk and can make us a lot of money," he told investors. 

Buffett's cash stockpile has been a hidden message for overvalued stocks... 

In this period of lackluster deal flow, Berkshire has turned to buying back its own shares. This lull in deal activity is due to the Fed's tight monetary policy to tame inflation.

Berkshire's 12% stake in Bank of America shows he still supports the bank's CEO: "I like Brian Moynihan enormously," he said in April.

Did Buffett just call the top in the market?