Microsoft Corp (NASDAQ:MSFT) has filed a legal brief supporting Anthropic in its challenge to the Pentagon’s designation of the AI company as a “supply-chain risk,” which effectively barred it from federal contracts.
The Department of Defense ended all contracts with Anthropic last month after the company refused to remove safeguards limiting military use of its AI model, Claude, including restrictions on mass surveillance and fully autonomous weapons. In response, Anthropic filed two lawsuits against the Pentagon.
In an amicus brief filed Tuesday, Microsoft asked a federal court to issue a temporary restraining order blocking the designation while the case is resolved. “A temporary restraining order will permit the parties to pursue a negotiated resolution that will better serve all involved and avoid wide-ranging negative business impacts,” Microsoft wrote.
The company also highlighted operational challenges for contractors forced to remove Anthropic’s models immediately, warning that such disruption could “potentially hamper US warfighters at a critical point in time.”
Anthropic CEO Dario Amodei framed the dispute as a legal and constitutional issue, saying the government’s actions were “unprecedented and unlawful” and violated protections for corporate speech.
“The use of a supply chain risk designation to address a contract dispute may bring severe economic effects that are not in the public interest,” Microsoft said in its filing in the US District Court for the Northern District of California.
The brief called the Pentagon’s directive “vague and ill-defined” and urged judicial oversight to allow for a more reasoned resolution.