In an email, Gwynne Shotwell, SpaceX’s president, said the letter had made other employees “feel uncomfortable, intimidated and bullied.”
SpaceX, the private rocket company, on Thursday fired employees who helped write and distribute an open letter criticizing the behavior of chief executive Elon Musk, said three employees with knowledge of the situation.
Some SpaceX employees began circulating the letter, which denounced Mr. Musk’s activity on Twitter, on Wednesday. The letter called the billionaire’s public behavior and tweeting “a frequent source of distraction and embarrassment” and asked the company to rein him in. Mr. Musk is currently closing a $44 billion deal to buy Twitter.
By Thursday afternoon, SpaceX had fired some of the letter’s organizers, according to the three employees and an email from Gwynne Shotwell, SpaceX’s president and chief operating officer. In her email, which was obtained by The New York Times, she said the company had investigated and “terminated a number of employees involved” with the letter.
“The letter, solicitations and general process made employees feel uncomfortable, intimidated and bullied, and/or angry because the letter pressured them to sign onto something that did not reflect their views,” Ms. Shotwell wrote. “We have too much critical work to accomplish and no need for this kind of overreaching activism.”
It was unclear how many employees were fired. James Gleeson, a SpaceX spokesman, did not immediately return a request for comment.
The open letter followed recently publicized accusations of sexual misconduct against Mr. Musk amid his contentious acquisition of Twitter. On Thursday, Mr. Musk addressed Twitter employees for the first time since his takeover offer via a video call to answer their questions.
In May, Insider reported that a flight attendant said Mr. Musk propositioned her for a sexual massage during a flight to London in 2016. The flight attendant said he also exposed himself to her and offered her a horse, according to the article, the details of which were not independently verified by The Times.
Mr. Musk called the accusations “utterly untrue” and joked about horses and his genitalia on Twitter. Last month, Ms. Shotwell said in an email to SpaceX employees that she “personally” believed the sexual harassment allegations against Mr. Musk were false.
At SpaceX, Mr. Musk is rarely challenged by his own workers, said the three employees, who spoke on the condition of anonymity. Earlier this month, he notified the company’s workers via email that they must spend at least 40 hours in the office or face firing.
The open letter about Mr. Musk’s online activity asked that SpaceX’s leaders “publicly address and condemn Elon’s harmful Twitter behavior” and “define and uniformly respond to all forms of unacceptable behavior.”
In her email to staff, Ms. Shotwell wrote, “Blanketing thousands of people across the company with repeated unsolicited emails and asking them to sign letters and fill out unsponsored surveys during the work day is not acceptable.”
“Please stay focused on the SpaceX mission, and use your time to do your best work,” she continued. “This is how we will get to Mars.”