Anthropic’s Mythos 5 is back

After a rollercoaster negotiation process with the Trump administration that dragged on for two weeks, Anthropic’s Mythos 5 is finally back in action — at least, somewhat, for a select group of organizations, according to a letter from the government to Anthropic that was viewed by The Verge. Fable 5, however — the public-facing Mythos-class model — appears to still be in limbo, with no apparent timeline for a rollout agreement.

Anthropic’s Mythos 5 is back

The Trump administration approved a select group of users, but Fable 5 is still nowhere in sight.

The letter, dated June 26th and sent by Commerce Secretary Howard Lutnick to Anthropic co-founder Tom Brown, who had been recently leading negotiations, states that there’s been a “revision to the license requirements” based on the fact that Anthropic has recently “worked with the U.S. government to address risks” associated with Mythos 5 and Fable 5.

Anthropic spokesperson Danielle Ghiglieri told The Verge in a statement that the company had “received notice from the US government that Mythos 5, our strongest cybersecurity model, can be redeployed to a small group of cyber defenders and infrastructure providers.” She added, “We are working to provision the approved set of providers and restore their access to Mythos 5 as quickly as possible. We are pleased to see this progress and continue to work with the government to expand access to Mythos 5 and make Fable 5 available for general use again.”

The US government did not lift the export control directive it hit Anthropic with two weeks ago, which barred any foreign national from accessing either model (including Anthropic’s own employees). Instead, the government essentially made an exception for Mythos 5, approving a select group of organizations for access the same way it did for OpenAI’s GPT-5.6, announced earlier today. Under this exception, Anthropic employees who aren’t US nationals *and *members of the approved organizations who aren’t US nationals are all greenlit to access Mythos 5, according to the letter.

“These efforts have yielded significant progress,” Lutnick wrote. “In addition, Anthropic has committed to work with the U.S. government on protocols and standards and releases for [Mythos-class models]. In light of this progress ... I have determined that appropriate safeguards are in place to permit certain trusted partners to access the Claude Mythos 5 Model.”

Pressure has been building on the Trump administration to make a change in the case-by-case type of regulatory environment it recently adopted, especially as Anthropic’s competitors’ cybersecurity-focused models kept getting better and better — and even pulling ahead of it on some cybersecurity-focused benchmarks. Pressure was also building within the US AI industry, particularly fears about the AI advancements China could make while top US AI labs were sidelined. Plus, there was the fact that top US government departments, like the National Security Agency, had lost access to Mythos 5.

Now, Anthropic has essentially the same deal OpenAI has: Release the model in a limited preview setting, for approved organizations only, such as trusted enterprises and the US government itself. Both AI labs hope that more general availability comes soon, both for enterprise deals and for public access (like with Anthropic’s Fable 5), but it’ll be ultimately up to the Trump administration. Though many have called for AI regulation, including AI labs themselves, a current consensus among some tech leaders is that the past two weeks haven’t been the way to do it.

In fact, OpenAI wrote in the company’s GPT-5.6 blog post, “We don’t believe this kind of government access process should become the long-term default. It keeps the best tools from users, developers, enterprises, cyber defenders, and global partners who need them. We are taking this short-term step because we believe it is the strongest path to broader availability in the coming weeks, while we work with the Administration to develop the cyber Executive Order framework and a repeatable process for future model releases.”

Lutnick wrote in his letter to Anthropic, “All other requirements of the June 12 letter remain in effect until further notice.” He added, “I reserve the right to reevaluate and adjust the scope of license requirements on [Mythos 5 and Fable 5], should circumstances change.”