The case is scheduled to go before an administrative judge in early March unless SpaceX agrees to a settlement beforehand.

“At SpaceX the rockets may be reusable, but the people who build them are treated as expendable,” said Paige Holland-Thielen, one of the employees who were fired. “I am hopeful these charges will hold SpaceX and its leadership accountable for their long history of mistreating workers and stifling discourse.”

SpaceX did not immediately respond to a request for comment.

Mr. Musk has sometimes taken a hard line toward his companies’ employees, as when he laid off roughly half the work force at Twitter, now known as X, shortly after buying the company in 2022. He later fired roughly two dozen internal critics at Twitter, which has lost about 80 percent of the 7,500 employees who worked there when the billionaire took over.

Tesla, where Mr. Musk is chief executive, has spent years litigating a case in which the labor board accused it of firing an employee for engaging in union activity. The board ruled in 2021 that the firing was illegal and ordered Tesla to reinstate the worker with back pay, a decision that a federal court affirmed. The company is appealing the case further.

The Justice Department sued SpaceX in August, accusing it of discriminating against asylum-seekers and refugees in its hiring, but a judge has issued an injunction blocking that case from moving forward.