Twitter stock is down some 40 percent since Jack Dorsey became CEO, and the other company he runs, Square, isn’t doing too well either, prompting Forbes to drub Dorsey out of the billionaire’s club on Thursday:

After the opening bell, Square shares dropped below $9.00 for the first time since the company started trading publicly in November, and the stock is down 35% since its IPO. Twitter, which hit its lowest price this year just after Wednesday’s opening bell, is down 57% in the past 12 months.

At the FORBES 400 in September, we pegged Dorsey’s net worth at $2.2 billion, thanks in large part to Square’s $6 billion dollar private valuation. His net worth dropped $800 million to just below $1.4 billion when the company went public in November at $11.20 a share. Now, with both companies struggling on the stock market, he’s fallen out of the three-comma club with a net worth of $944 million as of 10:30 a.m.

$944 million isn’t exactly dead broke, even by Hillary Clinton standards, so Dorsey probably doesn’t have to worry about saving money by canceling his Amazon Prime membership and making do without free shipping on orders under $35 just yet.

Still, it’s been a rough ride for Twitter and Square, an online payments company he co-founded, as he was co-founder of Twitter.  When Dorsey returned as Twitter CEO, there was some trepidation that he wouldn’t be able to properly manage both companies at once, especially since it has been said the reason his first tenure as Twitter CEO ended is that he wasn’t sufficiently focused on his duties.

Of course, this hasn’t been a banner day for the stock market overall, and some of Twitter’s problems could be structural, and essentially incurable.

The Street suggested that Twitter’s latest stock tumble was a consequence of analysts “noting that investors view the social media company’s stock as risky.”  Among the reasons cited for this dour prognosis were skepticism that Twitter has any means of turning an attractive profit, a failure to deliver on plans to grow the user base, and the disappointing historical performance of Twitter stock.

And then you’ve got the whole fiasco with Twitter wantonly de-verifying the account of Breitbart Tech editor Milo Yiannopoulos.  It’s probably not the only reason Jack Dorsey isn’t a billionaire any more, but alienating a large segment of the user base while suffering from an overall loss of users isn’t good business strategy.

This is also further evidence that picking a Twitter fight with Milo isn’t a good idea, even when Twitter itself does it.  It’s on par with feeding a gremlin after midnight, taking a position as Defense Against the Dark Arts instructor at Hogwart’s, beaming planetside with Captain Kirk as a security officer, or bringing your prom date to Camp Crystal Lake for a midnight beer party: an unnecessary invitation to doom.