Pentagon vs Anthropic: Microsoft and Tech Take a Stand

The Pentagon and Anthropic: An Unprecedented Confrontation

The United States Department of Defense recently made a controversial decision by placing Anthropic on a blacklist. This measure, typically reserved for foreign companies deemed suspicious, was applied to Anthropic after the latter refused to collaborate unconditionally with the U.S. military. This situation marks a first in the history of relations between Silicon Valley and the Pentagon.

Anthropic Says No to the Military

In March 2026, Anthropic took a firm stance by refusing to sign an agreement with the Department of Defense. The startup demanded specific contractual guarantees to ensure that its technology would not be used in autonomous weapons or for mass surveillance on U.S. soil. In response, the Pentagon labeled Anthropic as a "supply chain risk," a serious accusation. In light of this situation, Anthropic filed two federal lawsuits on March 9, denouncing what it considers an "illegal retaliation campaign."

Microsoft Steps In

On March 10, Microsoft surprised the industry by supporting Anthropic through an amicus curiae brief in a federal court in California. Microsoft's goal is to temporarily suspend the Pentagon's designation, arguing that without this suspension, companies working with the government will have to integrate a new risk into their business strategy. This support is not isolated: artificial intelligence researchers from Google and OpenAI have also expressed their support for Anthropic. According to court documents, this designation could cost Anthropic several billion dollars in 2026.

A Self-Interested Support

Microsoft's support for Anthropic is not without ulterior motives. For the past year, the two companies have maintained a business partnership. However, this action is part of a broader context where many engineers from Google and OpenAI have already voiced their opposition to the military use of their technologies. Other tech giants, such as Apple, NVIDIA, and Amazon, have also taken a stand against the Pentagon's decision to blacklist Anthropic.

The Stakes for Microsoft

For Microsoft, commercial stakes outweigh ethical considerations. As the primary IT provider for the U.S. military, Microsoft is involved in major programs like IVAS, valued at $21.9 billion, and Azure Government, the cloud platform of choice for many federal agencies. Historically, Microsoft has never imposed ethical conditions on its military collaborations. Internal documents revealed by The Guardian in January 2025 showed that Azure was used by Israeli military intelligence for mass surveillance operations, without any ethical clause. It was only in September 2025 that Microsoft scaled back some of these services under media pressure.

Anthropic's Position

Anthropic has drawn a clear red line by refusing to participate in mass surveillance projects. What Microsoft has allowed for years, Anthropic categorically rejects. Therefore, Microsoft's support for Anthropic is not an ethical issue, but rather a defense of companies' rights to set boundaries without risking exclusion from government contracts. If the Pentagon's precedent is upheld, it could mean that any compliance clause in a contract with the government could become grounds for exclusion.

The Pentagon's decision to use a mechanism originally designed for companies like Huawei against Anthropic sends a strong message to Silicon Valley: government contracts may now include an implicit clause of total obedience.