Microsoft has stood firm in its support for Anthropic even as the Pentagon refuses to back down from its controversial supply-chain risk designation, filing a court brief in a San Francisco federal court that calls for a temporary restraining order against the designation. The brief argued that the Pentagon’s action threatens the entire ecosystem of technology companies that rely on Anthropic’s AI. Amazon, Google, Apple, and OpenAI have similarly backed Anthropic through a joint filing, creating a unified industry front in what has become a high-stakes AI confrontation.
The confrontation began with a $200 million contract negotiation in which Anthropic refused to allow its Claude AI to be deployed for mass surveillance of US citizens or to power autonomous lethal weapons. Defense Secretary Pete Hegseth labeled the company a supply-chain risk after talks collapsed, and the Pentagon’s technology chief later publicly stated that renegotiation was impossible. Anthropic filed two simultaneous lawsuits challenging the designation in California and Washington DC.
Microsoft’s firm stance is grounded in its direct use of Anthropic’s AI in military systems it provides to the federal government and its status as a partner in the Pentagon’s $9 billion cloud computing contract. The company also holds additional agreements with government agencies worth several billion dollars more. Microsoft publicly called for cooperation between government and industry to ensure that AI advances national security responsibly.
Anthropic’s court filings argued that the supply-chain risk designation was an unconstitutional act of ideological retaliation for the company’s publicly stated AI safety positions. The company disclosed that it does not currently believe Claude is safe or reliable enough for lethal autonomous decision-making, which it said was the genuine basis for its contract demands. Anthropic noted that no US company had ever previously received this designation.
Congressional Democrats have separately pressed the Pentagon for information about whether AI was used in a strike in Iran that reportedly killed over 175 civilians at a school, raising questions about AI targeting tools and human oversight. Their formal inquiries are adding legislative urgency to a confrontation that shows no signs of resolution. Microsoft’s firm stance, the industry coalition, and congressional pressure together represent a formidable challenge to the Pentagon’s position.
