Anthropic delayed Mythos model release by four months for safety, says CEO

Anthropic’s Mythos models were first ready in February but were not made generally available until June, when stronger cyber safeguards were in place and only a small group of partners working on cyber defence could use them. The company also restricted sales to firms controlled by the People’s Republic of China, backed export controls on chips, contributed to California’s SB 53 safety law, blocked potential bioweapon use, and created a public benefit fund that will hold at least 5% of Anthropic’s shares. Amodei said the firm likely sacrificed a several‑month model lead to China’s GLM‑5.3.

The post, viewed more than 800,000 times, acknowledged that three of Calvin’s points could have been handled better and promised a review of the Responsible Scaling Policy. Vox’s Sigal Samuel asked for evidence the strategy works, noting an outside view of a race to the bottom.