On Monday, Anthropic filed a lawsuit against the U.S. Department of Defense after being labeled a supply chain risk. Within hours, nearly 40 employees from OpenAI and Google, including Google’s chief scientist Jeff Dean, submitted an amicus brief supporting Anthropic’s case. The brief criticized the Trump administration’s decision and warned of the dangers posed by certain military uses of artificial intelligence.

The dispute stems from Anthropic’s refusal to allow its AI technology to be used for domestic mass surveillance or fully autonomous weapons. Following the breakdown of negotiations, the Pentagon’s designation barred Anthropic from military contracts and restricted other companies using its products. The brief argued that the designation was retaliatory and harmful to the public interest, emphasizing that AI-driven surveillance and autonomous lethal systems pose serious ethical and governance risks.

The signatories, describing themselves as engineers and researchers from leading U.S. AI labs, urged for guardrails and human oversight in military AI applications, warning that current systems remain unreliable and potentially dangerous when deployed without proper constraints.