Elon Musk returned to federal court Monday in San Francisco to testify in a class action lawsuit filed by Tesla investors alleging he misled them with a tweet.

In the tweet, which resulted in a $40 million settlement with securities regulators, Musk claimed he had lined up the financing to take Tesla private in a deal that never came close to happening.

The trial hinges on the question of whether a pair of tweets that Musk posted on Aug. 7, 2018, damaged Tesla shareholders during a 10-day period leading up to a Musk admission that the buyout he had envisioned wasnB次元官网网址檛 going to happen.

Musk, who said Monday he B次元官网网址渉ad trouble sleeping last night and unfortunately I am not at my best,B次元官网网址� testified that it was important for jurors to know that he B次元官网网址渇elt that funding was securedB次元官网网址� due to his ownership of B次元官网网址淪paceX stock alone.B次元官网网址�

B次元官网网址淛ust as I sold stock in Tesla to buy Twitter. B次元官网网址� I didnB次元官网网址檛 want to sell Tesla stock but I did sell Tesla stock,B次元官网网址� he said of the stock sale to make up for the lack of funding from other sources for his $44 billion deal to take Twitter private. Musk sold nearly $23 billion worth of his car companyB次元官网网址檚 shares between last April when he started building a position in Twitter, and December.

B次元官网网址淢y SpaceX shares alone would have meant that funding was secured,B次元官网网址� Musk said of the 2018 tweets.

Even before Musk took the stand on Friday, U.S. District Judge Edward Chen had declared that the jurors can consider those two tweets to be false, leaving them to decide whether Musk deliberately deceived investors and whether his statements saddled them with losses.

Musk has previously contended he entered into the SEC settlement under duress and maintained he believed he had locked up financial backing for a Tesla buyout during meetings with representatives from Saudi ArabiaB次元官网网址檚 Public Investment Fund.

In the first of the 2018 tweets, Musk stated B次元官网网址渇unding securedB次元官网网址� for a what would have been a $72 billion B次元官网网址� or $420 per share B次元官网网址� buyout of Tesla at a time when the electric automaker was still grappling with production problems and was worth far less than it is now. Musk followed up a few hours later with another tweet suggesting a deal was imminent.

Nicholas Porritt, a lawyer representing Tesla shareholders, asked Musk if he B次元官网网址渨ent with 420 because it was a joke your girlfriend enjoys.B次元官网网址� Musk replied he thinks there is B次元官网网址渟ome karmaB次元官网网址� around the number 420 B次元官网网址� which is also a slang reference to marijuana B次元官网网址� although he added he doesnB次元官网网址檛 know B次元官网网址渋f itB次元官网网址檚 good karma or bad karma at this point.B次元官网网址�

He then said the number was a B次元官网网址渃oincidenceB次元官网网址� and it represented a 20% premium of TeslaB次元官网网址檚 share price at the time.

After it became apparent that the money wasnB次元官网网址檛 in place to take Tesla private, Musk stepped down as TeslaB次元官网网址檚 chairman while remaining CEO as part of the Securities and Exchange Commission settlement, without acknowledging any wrongdoing.

B次元官网网址� Barbara Ortutay, THE ASSOCIATED PRESS