Elon Musk Ordered to Delete Threatening 2018 Tweet to Tesla Workers, NLRB RulesThe Tesla CEO must remove a tweet that addresses the possible unionization of his workers, the board ordered on Thursday.

Tesla and SpaceX CEO Elon Musk must remove a 2018 tweet that threatened workers who wanted to unionize, the National Labor Relations Board (NLRB) ruled ina damning decision yesterday.

In a 55-page decision, the NLRB addressed allegations that Tesla had engaged in coercive action, instituted stringent rules and changed the terms and conditions of employment. In a 3-2 ruling, it found that the electric vehicle manufacturer violated the law by "coercively interrogating" employees who had been in the process of organizing and threatening to take away their stock options if they chose the union as their collective-bargaining representative.

Tesla also ran afoul of the law by including a provision in its confidentiality agreement that prevented employees from talking to the media about the company, the NLRB said. Tesla further broke the law when it fired union activist Richard Ortiz, who was named as one of the charging parties in the decision, in 2017.

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"Within 14 days from the date of this Order, [Tesla must] offer Richard Ortiz full reinstatement to his former job or, if that job no longer exists, to a substantially equivalent position, without prejudice to his seniority or any other rights or privileges enjoyed," the NLRB ruled.

The board additionally ordered Musk to delete a 2018 tweet addressing the possible unionization of Tesla employees.

"Nothing stopping Tesla team at our car plant from voting union," the billionaire businessmantweetedin May 2018. "Could do so tmrw if they wanted. But why pay union dues & give up stock options for nothing? Our safety record is 2X better than when plant was UAW & everybody already gets healthcare."

In calling out the tweet, the NLRB said that Musk's comment on removing stock options "unlawfully threatened the Respondent's employees in a manner viewable by the public without any limitations." In addition to instructing Musk to delete the tweet, the board asked the Tesla CEO to address its removal at all of Tesla's facilitlies nationwide.

In 2017, the United Auto Workers and several Tesla employees filed labor violation charges against the company, alleging that the company had tried to silence pro-union workers. In addition to forcing employees to sign the confidentiality agreement, Tesla security guards and human-resources employees purportedly threatened workers who passed out union-related leaflets,Business Insiderreports.

Musk has yet to address the board's decision, although, interestingly enough, hedid tweeton Thursday, "If there's ever a scandal about me, *please* call it Elongate."