Buffett, who turns 94 on Friday, has been chair of Berkshire Hathaway since 1970, transforming it from a small textile company into one of the world’s most valuable firms, and turning him into one of the world’s richest men.

On Wednesday, Berkshire Hathaway’s market capitalisation crossed US$1 trillion in early trading, putting it in an exclusive club alongside tech titans like Apple, Nvidia and Microsoft.

The company’s Class A shares closed up 0.8%, and its Class B shares closed up 0.9%, leaving it with a total market value of just over US$1 trillion.

It is the only publicly-traded, non-tech firm other than Saudi Arabia’s state-owned oil company, Saudi Aramco, to hit such heady heights. Electric vehicle maker Tesla, which previously hit a US$1 trillion market capitalisation, is considered to be a technology company by many analysts.

The Nebraska-based firm’s portfolio spans a vast array of sectors, including insurance, railroads and retail.

Buffett, who has been dubbed the “Sage of Omaha,” popularised a dispassionate, long-term approach to investing that ran counter to the short-term thinking of many market players at the time.

Buffett has been in a selling mood of late, convincing Berkshire Hathaway to dump large quantities of stock in some of its biggest holdings, including Apple and Bank of America, accumulating vast cash reserves.

The firm has plowed its growing cash pile into government bonds to such an extent that it now owns more short-term US Treasury bills than the Federal Reserve.