Microsoft backs Anthropic, urging a judge to halt Pentagon’s actions against AI company

SAN FRANCISCO (AP) — Microsoft is throwing its weight behind Anthropic in asking a federal court to block the Trump administration’s designation of the artificial intelligence company as a supply chain risk.

Microsoft, in a legal filing, is challenging Defense Secretary Pete Hegseth’s action last week to shut Anthropic out of military work by labeling its AI products as posing a threat to national security.

The Pentagon took the action against Anthropic after an unusually public...