Anthropic filed a lawsuit on Monday to block the Pentagon from placing it on a national security blacklist. The legal action escalates the artificial intelligence company’s dispute with the U.S. military over limits on the use of its technology. The startup filed the case against the U.S. government, President Donald Trump and Defence Secretary Pete Hegseth. The complaint outlines several constitutional and legal claims.
First Amendment dispute
Anthropic argues that the Pentagon retaliated against it for protected speech. Therefore, the company says the action violates the First Amendment, which protects free expression.
According to the lawsuit, the Constitution allows the company to express views about its own technology. It also protects its right to speak publicly about the limits of its artificial intelligence systems. In addition, the company says it has the right to communicate those concerns directly to the government.
However, Anthropic claims the Pentagon punished the company for those views. The lawsuit states that the government’s blacklisting decision represents retaliation for protected activities. These activities include public statements, policy viewpoints and petitions directed at government officials.
Challenge to presidential authority
The complaint also challenges actions attributed to President Donald Trump. Late last month, Trump posted on his social media platform Truth Social about directing the government to stop working with Anthropic.
Anthropic argues that this directive exceeded the president’s legal authority. In the filing, the company describes the move as ultra vires. In legal terms, that phrase means an action beyond authorised power.
Therefore, the lawsuit claims the order should not stand. The company argues that such direction cannot lawfully override established legal limits.
Fifth Amendment due process claims
The lawsuit also raises concerns about due process under the Fifth Amendment. Anthropic alleges the government effectively blacklisted the company without following required procedures.
According to the filing, agencies ended contracts and blocked future work without proper notice. Moreover, the company says officials denied it a meaningful chance to respond to the allegations.
As a result, Anthropic claims the government deprived it of due process protections guaranteed by the Constitution.
Administrative Procedure Act challenge
Anthropic also argues that the Defence Department violated the Administrative Procedure Act. The department designated the company as a supply chain risk and restricted contractors from working with it.
However, the company says that decision lacked proper legal procedure. The lawsuit claims officials failed to present supporting evidence.
Furthermore, Anthropic argues that Defence Secretary Pete Hegseth exceeded his authority when making the designation. The complaint also states that the action was arbitrary and did not follow established administrative requirements.
Through the lawsuit, Anthropic seeks to block the blacklist and challenge the legal basis for the government’s actions.
With inputs from Reuters

