Shares of Hewlett Packard $HPQ, the multinational computer and printer manufacturer company, are up as high as 15% in pre-market trading hours after Warren Buffett's Berkshire Hathaway $BRK.B $BRK.A disclosed they acquired a stake in the business valued at a whopping $4.2B (~121M shares).

This purchase marks Berkshire's third multibillion-dollar investment over the last month or so, after picking up $7.5B worth of Occidental Petroleum $OXY and their $11.6B takeover of Alleghany Insurance $Y.

A quote from the Financial Times reads as follows:

"The addition of HP stock to Berkshire’s portfolio signals that Buffett is still betting on corporate America and the US economy, even as Russia’s invasion of Ukraine raises the possibility of slower global growth and high inflation.

It marked a noticeable shift by a company that had largely sat out a spate of big dealmaking over the past six years as stock valuations soared. Buffett had complained about the lack of appealing investments as recently as February, writing to shareholders in his annual letter that he and his right-hand man Charlie Munger were finding “little that excites us”."

The disclosure on Wednesday with the SEC did not indicate whether Buffett made the investment in HP himself or if it was executed by one of the two portfolio managers on his team. The two managers, Todd Combs and Ted Weschler, oversaw just under a tenth of the company’s $351bn stock portfolio at the end of 2021, but Buffett has traditionally been the one to pull the trigger on larger transactions.