Topline<\/p>\n
Anthropic extended access for Claude Fable 5 for subscribers for the second time in a week, an apparent response to the launch of OpenAI\u2019s latest ChatGPT model\u2014which the rival firm claims sets a \u201cnew standard\u201d\u2014following Fable\u2019s turbulent debut overshadowed by its clash with the U.S. government.<\/p>\n
The U.S. quickly blocked the debut of Anthropic\u2019s Mythos models before they were released. <\/p>\n
NurPhoto via Getty ImagesKey Facts<\/p>\n
Anthropic, announcing<\/a> its decision Sunday on X, through an email to subscribers and an updated support page<\/a>, said Claude Fable 5 would be available to subscribers at no extra cost through July 19.<\/p>\n That marks the second time Anthropic has expanded access to Fable after launching<\/a> a one-week promotion on July 7, allowing Claude users to spend up to 50% of their weekly subscription limits on the model.<\/p>\n Even if users exhaust their expanded Fable access, they can still use the model by purchasing usage credits, which allow Claude subscribers to pay based on how much they use, Anthropic said.<\/p>\n The extension comes just three days after OpenAI launched<\/a> GPT-5.6, headlined by its flagship model Sol, which the company said achieved \u201cstate-of-the-art\u201d results in coding, knowledge work, cybersecurity and science while \u201coutperforming previous and competing frontier models\u201d at a lower cost.<\/p>\n OpenAI claimed Sol and its other new models outperformed Anthropic\u2019s Fable in coding tasks and that its rival\u2019s model failed to test for questions involving scientific research (Anthropic said<\/a> Fable would \u201cfall back\u201d to a previous model for most biology and chemistry requests).<\/p>\n will anthropic make mythos publicly available?<\/p>\n Anthropic has said it plans to open up Mythos\u2014its restricted flagship AI model, from which Fable is made with additional safety guardrails\u2014\u201cmore broadly in the future,\u201d though access is currently limited to roughly 150 organizations across more than 15 countries. Mythos was released last month to a \u201csmall number\u201d of partners for use in defensive cybersecurity, Anthropic said, indicating its latest version could be used to \u201cfind and exploit software vulnerabilities more effectively than any other model\u2014and all but the most skilled human security experts.\u201d <\/p>\n anthropic\u2019s rivalry with openai<\/p>\n Competition between Anthropic and OpenAI has become increasingly public in recent months. Anthropic CEO Dario Amodei, who spent nearly five years at OpenAI before leaving to co-found Anthropic in 2021, appeared<\/a> to say last month he departed the company over his distrust of OpenAI CEO Sam Altman: \u201cAt the end of the day, why argue with someone when you don\u2019t have the same vision and you don\u2019t trust them?\u201d That came months after Altman criticized<\/a> Anthropic for running an ad during the Super Bowl, accusing the rival firm of being \u201cso clearly dishonest\u201d and calling it \u201cauthoritarian,\u201d arguing OpenAI had no intention of serving ads in the way Anthropic portrayed. <\/p>\n key background<\/p>\n Anthropic debuted Fable in early June as a restricted variant of its more powerful Mythos model. The company noted Fable included safety features that blocked users from inquiring about cybersecurity, as well as biology and chemistry needed to create bioweapons. The Commerce Department forced Anthropic to pull the model days later, however, and the AI firm disclosed the government \u201cbecame aware\u201d of a report from researchers at Amazon who were able to bypass Fable\u2019s safety mechanisms. Researchers were able to get Fable to \u201cdemonstrate\u201d how a software security vulnerability could be exploited, according to Anthropic, which noted the technique used by the researchers was now \u201cblocked in over 99% of cases.\u201d Anthropic has been at odds with the Trump administration for months, after the Pentagon designated the firm a supply chain risk in March following a spat between officials and Anthropic, which refused to allow the government unrestricted access to its models.<\/p>\n