A federal judge has granted a preliminary injunction blocking the Federal Trade Commission’s investigation into left-leaning advocacy group Media Matters.

Back in 2023, Media Matters published research showing ads from major companies had appeared alongside antisemitic and other offensive content on Elon Musk-owned X. When major advertisers subsequently pulled back from the platform, X sued Media Matters. It also sued advertisers and advertiser groups over what it claimed was a “systematic illegal boycott.”

After Musk’s then-ally Donald Trump took office again in January, the FTC also began an investigation into whether Media Matters had illegally colluded with advertisers.

On Friday, however, Judge Sparkle L. Sooknanan sided with Media Matters and blocked the FTC’s investigation. In her decision, Sooknanan (a district court judge for the District of Columbia appointed by Joe Biden) wrote that the Media Matters article represented “quintessential First Amendment activity” and the FTC’s “expansive” investigative demands appeared to be “a retaliatory act.”

“It should alarm all Americans when the Government retaliates against individuals or organizations for engaging in constitutionally protected public debate,” she wrote. “And that alarm should ring even louder when the Government retaliates against those engaged in newsgathering and reporting.”

Sooknanan noted that before his appointment as the current FTC chair, Andrew Ferguson had appeared on Steve Bannon’s podcast and called for the FTC to investigate progressive groups criticizing online disinformation, and that he subsequently “brought on several senior staffers at the FTC who previously made public comments about Media Matters.”

The FTC did not immediately respond to a TechCrunch email asking whether it intends to appeal.

Regardless of the legal outcome, X’s lawsuits have already had a significant effect on the targeted organizations, with Media Matters cutting staff (one of the laid off researchers is now running for Congress), while the World Federation of Advertisers shut down its brand safety program and reportedly complained of drained finances.

Sooknanan said the FTC investigation has also had its “intended effect,” prompting Media Matters to decide “against pursuing certain stories about the FTC, Chairman Ferguson, and Mr. Musk.”