In the Tweet that started it all, Musk stated the takeout price at $420 and that funding was already secured.
"Disclosing news of this nature via twitter is unprecedented and, according to a former [Securities and Exchange Commission] chairman, may constitute fraud if Tesla does not already have the financing lined up," wrote UBS analyst Colin Langan. "The deal would likely require participation from numerous banks and institutional investors, and we think it likely that news of the deal would have leaked had Tesla already held discussions to secure funding."
Langan, who has a sell rating on the stock, linked to comments by former SEC Chairman Harvey Pitt.
"If his comments were issued for the purpose of moving the price of the stock, that could be manipulation, it could also be securities fraud," Pitt told CNBC on Tuesday.
A number of Wall Street banks contacted by CNBC were not aware of any deal and had not committed to funding a leveraged buyout of Tesla.
Bank of America Merrill Lynch gave Musk a little more credit but was still just guessing as to who could be funding the deal outside of the normal channels.
"Ultimately, we view today's announcement as having substance given what appears to be at least three potential sources of capital (existing shareholders, Saudi Sovereign Wealth Fund, Chinese government and investment funds)," wrote Merrill's John Murphy, who nonetheless still has an underperform rating on the stock.
Tesla spokesmen said they would have no further comment about the funding beyond its blog post.
Six members of the Tesla board issued a statement on Wednesday that said, "Last week, Elon opened a discussion with the board about taking the company private. This included discussion as to how being private could better serve Tesla's long-term interests, and also addressed the funding for this to occur. The board has met several times over the last week and is taking the appropriate next steps to evaluate this."