Warren Buffett’s Apple bet is paying off

Warren Buffett’s Berkshire Hathaway’s stake in Apple grew even larger just weeks before the tech giant became the first U.S. company to achieve a $1 trillion valuation, according to a regulatory filing made public on Saturday.

Berkshire disclosed that its stake in Apple, which represents its largest single investment in any company, was worth more than $47 billion as of the end of June. With Apple shares up more than 10% since late June, that stake was worth more than $50 billion as of market close on Monday.

The filing indicates that Berkshire increased its stake in Apple by more than 15 million shares in the quarter, the Wall Street Journal reported. The company owned nearly 240 million shares as of the end of its first fiscal quarter.

Buffett’s firm owns more than 5% of Apple, which surged in value last week after it beat expectations for second-quarter earnings. The company’s revenue rose as higher prices for its flagship iPhone offset slowing smartphone sales.

Berkshire Hathaway will disclose an updated share count for its Apple investment later this summer.

Buffett, who is a major proponent of Apple’s leadership, first acquired a stake in the company in 2016. The tech giant’s shares were slumping at the time due to concerns about sagging iPhone sales growth.