It seems unlikely Musk will get private equity funding for Twitter purchase

It "seems unlikely" Musk will get help from private equity firms with his $43 billion bid to buy Twitter and take it private, according to CNBC's David Faber.

"The more I report, the less I believe there's anybody else that really could show up here," Faber said on CNBC's "Squawk on the Street" Tuesday.

Though reports have suggested private equity firm Thoma Bravo may be interested in a bid for Twitter, Faber said the rates of return "don't work." Fellow private equity firm Apollo isn't interested in joining a private equity consortium to acquire the social media company, according to sources who asked not to be named because the discussions are private.

While Musk is considered to be the world's richest man, much of his assets are tied up in Tesla stock, meaning he'd likely have to either sell stock or borrow money to fund the deal.

"Yeah, he can do it, we know that," Faber said. "But how's he going to do it? Is he really going to choose to put that much of his net worth at risk?"

"Private equity is not real. That's all some marketing," Faber said.

Gordon Haskett Research Advisors analysts wrote in a note on Tuesday that the Wall Street Journal report, which first revealed Apollo was considering getting involved in a Twitter deal, "didn't impress us much, mainly because we've assumed most of the usual suspects, Apollo included, are updating their models."

But the analysts said Apollo could potentially help a firm like Thoma Bravo with its financing, noting it's "played a similar role on some other Bravo deals."

Apollo and Thoma Bravo did not immediately respond to CNBC's requests for comment.

CNBC's Alex Sherman contributed to this report.

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