Anthropic has filed a lawsuit against the US government to block the Pentagon from adding the company to a national security blocklist. The Department of Defense recently labeled Anthropic a supply chain risk, prompting CEO Dario Amodei to vow legal action. The lawsuit argues the designation violates free speech and due process rights.

In a statement, Anthropic called the government's actions 'unprecedented and unlawful,' claiming the Constitution doesn't permit punishing a company for protected speech. An Anthropic spokesperson told Engadget that seeking judicial review won't change their commitment to national security AI development, but is necessary to protect their business, customers, and partners. The company says it will continue pursuing resolution through dialogue.

The legal battle follows weeks of escalating tensions. In February, Defense Secretary Pete Hegseth pressured Anthropic to remove AI safeguards, threatening a supply chain risk designation and cancellation of a $200 million contract. President Trump ordered federal agencies to cease using Anthropic services. Despite this, Anthropic claims it agreed to collaborate on transitioning to another AI provider willing to meet Pentagon demands.