Anthropic is asking a federal appeals court to rehear its Pentagon blacklist fight

Anthropic filed a petition Tuesday asking the full U.S. Court of Appeals for the District of Columbia Circuit to rehear its challenge to the Pentagon's designation of the company as a national security supply chain risk, according to CNBC.

The petition targets a Sept. 25 ruling in which a divided three-judge panel voted 2-1 to sustain the Pentagon's blacklist of Anthropic's Claude AI models, according to Bloomberg. In Anthropic's view, the majority let the DOD proceed "without any pre-designation process and despite straightforward evidence the designation was retaliation for Anthropic's speech about AI safety."

"The Secretary of War branded Anthropic — an American AI company whose models help defend the nation — a national-security 'supply chain risk' because it declined to permit its models to be used for mass surveillance of Americans or lethal autonomous warfare and publicly explained those AI-safety commitments," Anthropic's attorneys wrote in the filing. "A divided panel upheld that extraordinary designation."

A Pentagon spokesperson told CNBC the agency does not comment on pending or ongoing litigation. A representative for Anthropic declined to comment to CNBC beyond the filing.

The conflict between Anthropic and the Trump administration stems from a breakdown in contract negotiations over how the military could deploy the company's Claude models. Anthropic had signed a $200 million contract with the Pentagon in July 2025, but talks collapsed that September when the company sought guarantees that Claude would not be used in autonomous lethal weapons systems or for domestic mass surveillance — conditions the DOD rejected. Defense Secretary Pete Hegseth then designated Anthropic a supply chain risk in March, effectively barring Pentagon contractors and suppliers from using the company's technology. Historically, such designations have been reserved for firms based in countries the U.S. considers adversaries.

Anthropic responded by filing two lawsuits. The D.C. Circuit case challenges the legality of the risk designation itself, while a parallel case in San Francisco targeted a separate DOD directive ordering federal agencies to stop working with the company.

The outcomes in the two courts have diverged. In the D.C. Circuit case, Judge Gregory Katsas authored the majority opinion, concluding that the Defense Department had legitimate grounds to worry that Anthropic could alter Claude's behavior in ways that would render it unfit for missions the department viewed as essential. In the California case, U.S. District Judge Rita Lin ruled in August that the DOD had violated Anthropic's First Amendment rights and that the supply chain risk designation amounted to illegal retaliation, ordering the government to rescind all directives issued against the company.