Anthropic’s Fable 5 and Mythos 5 return as US eases AI export curbs

Anthropic said it will begin restoring global access to Claude Fable 5 and Mythos 5 on Wednesday after the US Department of Commerce lifted export restrictions on the two frontier AI models ^[1]. The ban had been abruptly imposed on 12 June over concerns the models could be used to exploit weaknesses in computer systems, just three days after their release on 9 June ^[1].

In a letter to Anthropic, Commerce Secretary Howard Lutnick wrote that the company had agreed to “proactively detect and address security risks,” collaborate on future releases, and alert the government to malicious activity ^[1]. The Commerce Department reserved the right to reconsider the decision if necessary ^[1].

The Verge reported that Anthropic trained an improved safety classifier to block the jailbreak technique flagged by Amazon researchers, claiming it now blocks the specific method in over 99% of cases ^[2]. Anthropic also pledged pre-release government access and evaluation for models with national security implications, rapid information sharing on jailbreaks, and a “shared, voluntary security and evaluation standard” with other labs ^[2].

The episode is part of a broader shift in US AI oversight. OpenAI launched a limited preview of GPT-5.6 Sol last week, also under government pressure to stagger release to a small group of trusted partners before broader availability ^[3]. OpenAI said it does not want government access processes to become the long-term default, but is taking the step while the administration develops a cyber Executive Order framework ^[3].

In world news, uncertainty over US-Iran negotiations is keeping oil markets on edge. Brent crude rose to $73.28 a barrel and WTI to $69.84 as the Strait of Hormuz remains only patchily reopened ^[4]. Qatar’s Foreign Ministry said US envoys Jared Kushner and Steve Witkoff are in Doha, but no direct or high-level meetings with Iranian officials are currently scheduled ^[4]. Meanwhile, a Hamas delegation met Egyptian and Turkish intelligence chiefs in Cairo to advance the US-brokered Gaza ceasefire, though Israel’s near-daily attacks have killed more than 1,000 Palestinians since the truce was announced and humanitarian conditions remain dire ^[4].