July 6 (Reuters) - A federal judge on Monday rejected Elon Musk's request to overturn a jury verdict that found the world's richest man cheated Twitter investors by trying to drive down the company's share price after he agreed to a $44 billion takeover deal.

However, U.S. District Judge Charles Breyer in San Francisco acquitted Musk of responsibility for one of his tweets in dispute.

"Even if a speaker changes their mind or has temporary regrets about a deal, these concerns do not justify lying to investors," Breyer wrote.

Following the ruling on March 20, the investors' lawyer estimated that the total damages could reach approximately $2.5 billion.

Musk's lawyers have not yet responded to requests for comment. Lawyers for the investors have also not yet responded to similar requests.

Musk changed Twitter's name to X, and it is now part of his rocket and satellite company, SpaceX. Musk also faces a lawsuit in Manhattan accusing him of defrauding Twitter investors by delaying disclosure of his initial investment, allowing him to buy shares at bargain prices and subsequently sell them at even lower prices.

The jury found Musk guilty of manipulating two tweets he posted on May 13 and 17, 2022, in which he questioned whether Twitter was suffering from a proliferation of fake accounts and spam.

A tweet on May 13 said the purchase was "pending" pending details on whether fake accounts and spam represented less than five percent of users, while a tweet on May 17 said the purchase "should not go ahead" until Twitter's CEO proved that the figure was less than five percent.

Investors said Musk did this to force Twitter to renegotiate his offer or allow him to withdraw it. They also said the initial tweet caused Twitter's stock price to drop 18 percent in two trading days, resulting in losses when they sold their shares at the lower prices.

Breyer found "substantial evidence of deception" in the May 13 tweet, and said that "a jury could conclude that Musk had a motive to withdraw from the existing deal, and used fake accounts and spam as a pretext for doing so."

Judge Musk agreed that the lack of market reaction to the May 17 tweet meant that it did not cause investors to lose money.