The New York Times, Associated Press, Guardian and other news organizations have joined the roster of outside groups urging a federal appellate court to prevent the Federal Trade Commission from resuming its investigation of the watchdog Media Matters for America.

In papers filed Monday with the D.C. Circuit Court of Appeals, the news organizations argue that the FTC's investigation "targets core protected press activities."

The FTC "seeks information about newsgathering and editorial processes and punishes the publication of information about a matter of public concern, threatening both the dissemination of information of public concern and the predicate processes integral to it," the media organizations write.

They are weighing in on a battle between Media Matters and the FTC that began last June, when Media Matters sought a court order blocking the FTC from pursuing a broad "civil investigative demand" (comparable to a subpoena) for a trove of information.

Among other documents, the FTC sought information regarding Media Matters' finances and newsgathering, and material related to the Interactive Advertising Bureau, World Federation of Advertisers and its now defunct Global Alliance for Responsible Media, Check My Ads, the Center for Countering Digital Hate, Double Verify and NewsGuard, among other groups.

Media Matters claimed the FTC sought the information in retaliation for a November 2023 report that ads for Apple, Bravo, IBM, Oracle and other brands were being placed next to pro-Nazi posts on Elon Musk's X. (Musk also sued Media Matters over the report; that matter is ongoing.)

U.S. District Court Judge Sparkle Sooknanan in Washington, D.C. sided against the FTC, ruling in August that its demand for information was likely issued with "retaliatory animus," and therefore unconstitutional.

The FTC recently sought to lift the injunction, arguing that its investigation concerns "potential anticompetitive collusion in the digital advertising industry to withhold advertising from certain disfavored media."

The New York Times and other news organizations oppose the FTC's request, arguing that the agency's investigation targets "quintessential press activity protected by the First Amendment."

The FTC "claims novel authority to issue sweeping investigative demands to a media organization," the news companies write.

"Though its exact legal theory is hard to pin down, the agency seems to contend that Media Matters, simply by writing about advertisements appearing on social media and advertisers’ business decisions, has either itself participated in an advertising boycott or otherwise opened itself to regulatory scrutiny," the groups say. "Left unchecked, the FTC’s theory poses serious risks to news organizations’ ability to gather and disseminate the news."

Numerous other outside groups have also sided with Media Matters in separate friend-of-the-court briefs.

The appellate court has scheduled oral arguments for April 13.