For Musk, who has called Bezos’ company “Sue Origin,” this fight is personal and years in the making. In an early Thursday morning post on his platform X, he gleefully accused Bezos of telling others to sell their SpaceX and Tesla stock because Trump would lose the election. Tesla stock prices have soared since news of Trump’s victory.

A social media spat between Elon Musk and Jeff Bezos this week underscored a sharpening rivalry between two of the world’s richest men at a time when both are trying to grow their sprawling businesses empires in President-elect Trump’s second term.

Elon Musk, as a businessman, is primarily known for three of his many enterprises. One is X, formerly Twitter, nowadays judged by investment giant Fidelity to be worth perhaps a quarter of what it cost him.