US judge blocks Pentagon blacklisting of AI firm Anthropic

A United States judge has blocked the Pentagon’s blacklisting of technology company Anthropic.

In a 59-page written order issued on Thursday night, District Judge Rita Lin ruled that the Department of Defense had acted illegally when it designated the company a supply chain risk to national security.

The decision marks the latest turn in the Claude maker’s high-stakes fight with the US military over artificial intelligence safety on the battlefield. The government is expected to fight the ruling.

The judge’s order rebuked the Pentagon, saying it had targeted and punished Anthropic for the company’s public criticism of the Defense Department’s stance on AI deployment on the battlefield.

“The empty invocation of national security is not a blank check to punish and retaliate against government critics,” Lin, an appointee of former President Joe Biden, wrote.

Autonomous weapons and domestic surveillance

Anthropic’s lawsuit in a California federal court alleges that Defense Secretary Pete Hegseth overstepped his authority when he designated the company a national security supply-chain risk.

Hegseth’s move, which blocked Anthropic from military contracts, followed the company’s refusal to allow the military to use its Claude AI models for US surveillance or autonomous weapons.

Anthropic argues that AI models are not reliable enough for autonomous weapons and opposes domestic surveillance. The Pentagon maintains that private companies should not constrain military action.

Executives have said the ban could cost the company billions of dollars in lost business.

During a hearing on July 30, Lin described the government’s position as “really troubling” and “at odds … with the First Amendment”, adding that the record had “gotten worse for the government” over time.

In the same hearing, Department of Justice lawyers argued that the nature of AI models is “so staggeringly enormous and opaque” that the Pentagon cannot evaluate them like physical hardware.

Anthropic welcomed the ruling, stating it remained “focused on working productively with the government to harness AI for our national security so all Americans benefit from this technology”.

The designation was the first time a US company has been publicly labelled a supply-chain risk under an obscure procurement statute aimed at protecting military systems from foreign sabotage.

In its lawsuit, Anthropic alleged the government violated its constitutional rights to free speech and due process by retaliating against its views on AI safety without allowing it to dispute the claim.

The lawsuit called the decision unlawful, unsupported by facts, and inconsistent with the military’s past praise of Claude.

There was no immediate comment from the Pentagon on the ruling.