Some SpaceX employees circulated the letter on June 15, urging the company to denounce the billionaire's "harmful Twitter behavior," per The Times. The letter followed an Insider report in May about SpaceX settling a sexual harassment claim against Musk, which he made jokes about on Twitter.
The day after the letter was shared, SpaceX fired the organizers behind it, according to media reports. The Times reported it was unclear how many workers had been sacked, while Reuters said at least five employees had lost their jobs over the letter, citing two sources.
It's now understood that nine SpaceX employees were fired over the letter, The Times reported on Thursday, citing workers and lawyers.
The newspaper reported that charges alleging unfair labor practices were filed on Wednesday with the National Labor Relations Board involving eight of nine of the fired employees. The charges alleged it was against the law for SpaceX to fire the workers, per the report.