Maybe Elon Musk shouldn't have quite so many jobs

• Elon Musk runs Tesla and a lot of other companies at the same time.

• Normally investors don't like CEOs to do that. But they've given Musk a pass.

• But now there are real investor concerns about Tesla. Will that force Musk to narrow his focus?

Elon Musk runs Tesla. And Space X. And the company formerly known as Twitter. And Neuralink, the company making chips that are supposed to go in your brain. And a company that operates a tunnel under Las Vegas. And an AI startup, too.

Normally, people who run big publicly traded companies are encouraged to just do that one thing and are discouraged from doing side projects. But Musk does his own thing, and for a long time, the idea that he's a guy who does so many things was part of the pitch: Normal people couldn't pull this off, but Elon is Not Normal.

None of this is secret. Tesla spells it out to shareholders in its public filings, where it describes all of Musk's other jobs.

And this year's proxy filing describes how some of those jobs intersect: Tesla, for instance, has spent $200,000 advertising on the company formerly known as Twitter; and Twitter has spent $1.2 million via "commercial, consulting and support agreements" with Tesla — which presumably refers to Tesla staff who have worked on Twitter since Musk bought it in 2022 (though Musk has previously described some of that work as volunteering). There are also interlocks between Tesla and Space X; and Tesla and Musk's tunnel company.

And on top of all that, Musk has essentially used the fact that he runs other companies to justify his demands for a $55 billion pay package from Tesla — if he didn't get it, he posted on the social network formerly known as Twitter, he'd be tempted to spend more time doing cutting edge work at one of his other outlets.

And for a long time, this has all been … fine. Particularly over the last few years, when the market fell head over heels for Tesla and turned it into a company with a trillion-dollar valuation.