Someone Is Suing the U.S. For Making Them Go Without Anthropic’s Fable 5 Model

AI startup Legion is suing the U.S. government after Anthropic removed its Claude Fable 5 model from public access, complying with an export control directive. Legion claims the loss of the model caused immediate, irreparable harm to its business, which relies on the AI for legal document drafting. The lawsuit highlights tensions between national security controls and commercial access to advanced AI.

Anthropic’s Claude Fable 5 AI model was released to the public on June 9 and taken down on June 12. By my math, it was available for a little over three days. Anthropic took down Fable 5 voluntarily in a manner of speaking, but by all accounts it was complying with an export control directive from the U.S. government under threat of penalties. Now a startup called Legion says in a new lawsuit against the government that Claude Fable 5 was so critical to its business that, “Each day the directive remains in force disrupts Legion’s product, operations, sidelines its engineers, and erodes the company’s ability to survive in a field defined by continuous access to the most capable models,” according to Bloomberg https://www.bloomberg.com/news/articles/2026-06-23/anthropic-customer-sues-us-over-losing-access-to-fable-ai-model?srnd=phx-technology , which pulled that line from the court filing. Legion, by the way, is an AI company for lawyers. According to its about page https://legion.law/about/company , its product works like this: “Upload your case documents. Legion drafts your pleadings, discovery, and motions in minutes – with built-in editing tools to refine and ship. Export a fully formatted Word document or a bookmarked PDF with exhibits and slip sheets. Ready to file, ready to serve.” Arthur Rothrock, the CEO of Legion, said to Bloomberg, “Who’s to say they can’t do this any other time against another company, like OpenAI?” When Anthropic took down Fable 5, Legion says it “lost the latest tool at the center of its development instantaneously,” which caused, “immediate, irreparable and existential” harm, again per Bloomberg. Legion’s staff, Bloomberg notes, includes Canadian nationals located in Canada. The Fable 5 model, the most advanced, consumer-facing version of Claude, was part of the same class as the Claude Mythos Preview model which Anthropic had said was too dangerous to release to the public https://gizmodo.com/anthropics-new-model-is-so-scarily-powerful-it-wont-be-released-anthropic-says-2000743234 . Fable arrived about two months later https://gizmodo.com/anthropic-releases-a-safer-version-of-its-too-dangerous-mythos-ai-2000769492 , advertised as a version of Mythos with elaborate and conspicuous safeguards. But shortly after its release, the government—according to media reports https://www.wsj.com/tech/ai/amazon-ceos-talks-with-u-s-officials-triggered-crackdown-on-anthropic-models-dcc90578 from multiple publications https://www.theinformation.com/articles/amazons-jassy-raised-concerns-anthropic-model-trump-crackdown —was informed that Amazon researchers had found workarounds that bypassed the safeguards. This, reportedly combined with previous worries https://gizmodo.com/the-white-house-was-reportedly-ready-to-go-after-claude-mythos-long-before-fable-5-was-released-2000772295 that China-connected entities had access to Mythos, apparently led to the export control order, requiring Anthropic to keep Mythos and Fable away from anyone not a U.S. national. Faced with implementing an almost impossibly intricate citizenship-confirmation scheme in order to use Fable 5, Anthropic announced that it was pulling the plug https://www.anthropic.com/news/fable-mythos-access . Efforts to resolve the issue https://gizmodo.com/anthropic-leaders-are-reportedly-in-washington-d-c-trying-to-resolve-their-latest-issues-with-the-trump-administration-2000771655 have been ongoing. Anthopic’s statement to Bloomberg when asked about the suit says it is “grateful to the administration,” and remains, “committed to working alongside the government towards our shared goals of protecting critical infrastructure and making sure the US leads in AI.” The White House and Commerce department apparently didn’t respond to Bloomberg.