The conglomerate is making a comeback. But instead of combining jet engines with, say, broadcast television, the diversification play comes from cryptocurrency. On Monday, a securities filing from Tesla showed the electric vehicle company had purchased $1.5bn worth of bitcoin in January. Chief executive Elon Musk likes to tweet about bitcoin and digital currency Dogecoin, playfully or otherwise. But his company’s fortunes remain tied to ramping up production of vehicles. The $1.5bn investment in bitcoin is less than a tenth of Tesla’s cash balance and well under 1 per cent of its market capitalisation.

Musk’s foray into bitcoin is eye-catching but relatively tame compared with that of software boss Michael Saylor. The founder of dotcom-era darling MicroStrategy has called bitcoin “thermodynamically sound money”. In 2020 MicroStrategy spent $1.125bn buying bitcoin at an average price of $16,000 a piece.

Bitcoin surged on Monday to more than $43,000. One year ago, MicroStrategy shares traded at $150. They now exceed $900, implying a market capitalisation of almost $9bn. Roughly a third of that can be ascribed to the company’s bitcoin portfolio.