Anthropic wins court pause on Pentagon Claude ban

A US federal judge in San Francisco has temporarily blocked Pentagon action against Anthropic, giving the AI company short-term relief in its fight with the Trump administration. 

The ruling keeps federal agencies from enforcing a stop-use order against Claude for now and places the legal focus on whether the government acted beyond its authority.

Judge Rita Lin of the US District Court for the Northern District of California granted a preliminary injunction on Thursday. The order stops the Pentagon from enforcing its supply chain risk label against Anthropic while the case moves forward.

The ruling also pauses President Donald Trump’s directive that told federal agencies to stop using Anthropic’s chatbot, Claude. The judge said the record did not support the government’s position at this stage of the case.

Judge Lin wrote, 

“Nothing in the governing statute supports the Orwellian notion that an American company may be branded a potential adversary and saboteur of the US for expressing disagreement with the government.” 

She also described the measures against Anthropic as “arbitrary, capricious, [and] an abuse of discretion.”

The case follows a breakdown in talks between Anthropic and the Pentagon. In July 2025, the company had reached a deal that would have made Claude the first frontier AI model approved for use on classified networks.

That process later changed course. Anthropic said Pentagon officials wanted the company to permit military use of Claude “for all lawful purposes” and without limits. The company refused to allow uses tied to lethal autonomous weapons and mass domestic surveillance.

Anthropic has said its technology should not support those activities. The disagreement became public after contract talks collapsed in February and the company challenged the government’s response in court.

Court reviews retaliation claim

Anthropic filed its lawsuit on March 9 in federal court in Washington, DC. The company argued that Defense Secretary Pete Hegseth exceeded his authority by naming Anthropic a national security supply chain risk.

During a March 24 hearing in San Francisco, Judge Lin pressed government lawyers on whether Anthropic faced punishment for publicly criticizing the Pentagon’s position. The March 26 ruling said, “punishing Anthropic for bringing public scrutiny to the government’s contracting position is classic illegal First Amendment retaliation.”

Anthropic later said it was “grateful to the court for moving swiftly” and said the ruling showed it was likely to succeed on the merits.

Furthermore, the court fight comes as Anthropic holds a strong place in enterprise AI. Menlo Ventures said the company held 32% of that market in 2025, ahead of OpenAI at 25%.

A government-wide ban could have weakened that standing. For now, the court order gives Anthropic time to defend its position while the wider case moves ahead.