Hundreds of technology professionals have endorsed an open letter calling on the Department of Defense to retract its move to label Anthropic as a “supply chain risk.” The letter further requests Congressional oversight to “examine whether the use of these extraordinary authorities against an American technology company is appropriate.”

Signatories to the letter include employees from prominent technology and venture capital firms such as OpenAI, Slack, IBM, Cursor, and Salesforce Ventures. This action follows a disagreement between the DOD and Anthropic, which arose after the AI laboratory declined last week to provide the military with unrestricted access to its AI systems.

During negotiations with the Pentagon, Anthropic established two firm boundaries: it would not permit its technology to be used for mass surveillance of American citizens or to power autonomous weapons systems capable of making targeting and firing decisions without human oversight. The DOD stated it had no intention of pursuing those applications but also asserted it should not be constrained by a vendor’s rules.

Following Anthropic CEO Dario Amodei’s refusal to comply with the threats from Pentagon officials, President Donald Trump directed federal agencies on Friday to cease using Anthropic’s technology after a six-month transition period. Officials confirmed they would follow through on their warning to designate Anthropic a supply chain risk—a classification typically applied to foreign adversaries that would prohibit the AI firm from engaging with any agency or contractor doing business with the Pentagon.

In a public statement on Friday, a Pentagon representative wrote: “Effective immediately, no contractor, supplier, or partner that does business with the United States military may conduct any commercial activity with Anthropic.”

However, a public post alone does not formally enact a supply chain risk designation. The government must complete a formal risk assessment and notify Congress before military partners are required to sever ties with Anthropic or its products. Anthropic argued in a blog post that the potential designation is “legally unsound” and vowed to “challenge any supply chain risk designation in court.”

Many within the tech industry view the administration’s actions as severe and overt retaliation. “When two parties cannot agree on terms, the normal course is to part ways and work with a competitor,” the open letter states. “This situation sets a dangerous precedent. Punishing an American company for declining to accept changes to a contract sends a clear message to every technology company in America: accept whatever terms the government demands, or face retaliation.”

Beyond concerns about the government’s punitive treatment of Anthropic, many industry experts remain worried about potential governmental overreach and the misuse of AI for harmful purposes. Boaz Barak, a researcher at OpenAI, noted in a social media post on Monday that preventing governments from using AI for mass surveillance is also his “personal red line” and “it should be all of ours.”

Shortly after President Trump’s public criticism of Anthropic, OpenAI announced it had secured its own agreement for deploying its models within the DOD’s classified environments. OpenAI CEO Sam Altman stated last week that his company maintains the same core principles as Anthropic.

“If anything good can come out of the events of the last week, it would be if we in the AI industry start treating the issue of using AI for government abuse and surveilling its own people as a catastrophic risk of its own right,” Barak wrote. “We have done a good job of evaluations, mitigations, and processes, for risks such as bioweapons and cyber security. Let’s use similar processes here.”