Elon Musk, founder of SpaceX and chief executive officer of Tesla, waves as he arrives for a discussion at the Satellite 2020 conference in Washington, DC on Monday, March 9, 2020.

Andrew Harrer | Bloomberg | Getty Images

The National Labor Relations Board ruled that Tesla was breaking labor laws by firing a union activist, and when CEO Elon Musk wrote on Twitter in 2018, “Nothing is stopping the Tesla team at our auto plant from voting for the union. Could do this if they wanted to. But why pay union dues and give up stock options for nothing? “

The federal agency has ordered Tesla to ask Musk to remove his offensive tweet and offer the dismissed employee a job.

The employee was part of an organization campaign “Fair Future at Tesla”. At the time of the campaign, Tesla said its business should remain union free. But Musk’s public comments on his Twitter account, on which he has tens of millions of followers, have been viewed as threatening. Tesla considers tweets from Elon Musk to be official corporate communications, as stated in the financial filings.

News of the decision was previously reported by Bloomberg and confirmed by the United Auto Workers who brought the suit. UAW said it was preparing a statement and Tesla was not immediately available to comment.

Thursday’s decision was in line with a September 2019 decision by an administrative judge who had previously examined the complaint. Tesla contested this until full board.

That story is evolving – look back for updates.

Michael Wayland contributed to this report.