Warren Buffett's Apple stake just hit a record $152 billion — but the investor missed out on another $8 billion by selling shares

• Warren Buffett's Apple stake soared in value to a record $152 billion on Tuesday.
• Buffett's Berkshire Hathaway would have a $173 billion position if it hadn't sold any Apple shares.

Warren Buffett's Apple stake surged in value to a record $152 billion on Tuesday, as the technology stock climbed as much as 4% to $172 a share. The famed investor has more than quadrupled his money on the iPhone maker in a few short years, despite leaving about $8 billion on the table by trimming his position.

Buffett's Berkshire Hathaway spent about $36 billion amassing just over 1 billion Apple shares between 2016 and mid-2018, adjusted for the 4-to-1 stock split last year. However, it slashed its holding by 12% to 887 million shares by the end of 2020. That figure was unchanged as of September 30 this year.

Berkshire pocketed about $11 billion from its Apple stock sales in 2020, Buffett noted in his latest shareholder letter. The company netted another $2 billion or so from its disposals between the third quarter of 2018 and the end of 2019.

If Berkshire hadn't sold any shares, its Apple stake would be worth as much as $173 billion — $21 billion more than its current value. Subtract the roughly $13 billion cashed out by Buffett and his team, and they potentially missed out on $8 billion in unrealized gains.

Buffett acknowledged during Berkshire's annual shareholder meeting in May that he likely erred in pruning his Apple stake.

"That was probably a mistake," he said, adding that his business partner and Berkshire's vice-chairman, Charlie Munger, had advised him not to trim the position.

Apple is by far the largest holding in Berkshire's US stock portfolio, accounting for 43% of its total value of $293 billion at the end of September. The tech bet is worth more than the next four biggest positions — Bank of America, American Express, Coca-Cola, and Kraft Heinz — combined.

Berkshire's 5.4% stake in Apple makes it the company's second-largest shareholder after Vanguard, the index-fund titan. Buffett's company received a $785 million dividend from Apple this year, and pocketed an average of $776 million a year from the investment between 2018 and 2020.

Buffett has championed Apple on several occasions. He called it "probably the best business" he knows in a CNBC interview last year, and labeled it a "family jewel" in his latest shareholder letter. He also described Apple CEO Tim Cook as "one of the best managers in the world" at Berkshire's annual meeting this year, and underscored the widespread passion for Apple products and how many people view them as indispensable.

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