(Bloomberg) -- Elon Musk asked the US Supreme Court to consider invalidating an agreement with the Securities and Exchange Commission to have his posts about Tesla Inc. on his X social media network screened in advance.

In an appeal filed Thursday, Musk said the accord violates his free speech rights under the Constitution’s First Amendment.  

The provision “is a quintessential prior restraint that the law forbids,” argued Musk, the chief executive of Tesla and owner of X Corp., formerly known as Twitter.

A federal appeals court ruled against Musk in May, rejecting his contentions in a seven-page order issued just days after the panel heard arguments.

“We see no evidence to support Musk’s contention that the SEC has used the consent decree to conduct bad-faith, harassing investigations of his protected speech,” the panel said, upholding a lower-court ruling.

Musk has been battling with the SEC over his social media posts since he tweeted in 2018 that he had “funding secured” to take Tesla private, sending shares of the electric carmaker surging. The regulator sued, claiming Musk and Tesla had misled shareholders. 

The two settled with the SEC, each paying $20 million and agreeing that Musk’s Tesla-related tweets would be reviewed by an in-house lawyer before he posts them.

The Supreme Court appeal, which doesn’t yet have a docket number, is Musk v. Securities and Exchange Commission.

--With assistance from Bob Van Voris and Chris Dolmetsch.

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