Anthropic Withdraws OpenAI’s Access to Claude Models

A report from Wired indicates that Anthropic has cut off OpenAI’s access to its Claude AI models.

Sources quoted by Wired reveal that OpenAI had been integrating Claude into its internal systems to evaluate its performance in areas like coding, writing, and safety, comparing it to their own models.

TechCrunch sought comments from both Anthropic and OpenAI. An Anthropic representative told Wired, “OpenAI’s technical team was utilizing our coding tools prior to the launch of GPT-5,” labeling this as “a clear violation of our terms of service.” (Anthropic’s agreements prohibit using Claude for the development of competing products.)

Despite this, Anthropic stated it would still allow OpenAI access for “benchmarking and safety evaluations.”

In response, an OpenAI spokesperson said, “While we understand Anthropic’s decision to terminate our API access, it is disappointing, particularly as our API remains available to them.”

Anthropic leaders have previously shown hesitance in granting access to competitors. Chief Science Officer Jared Kaplan defended the choice to sever ties with Windsurf (a company reportedly sought for acquisition by OpenAI, but ultimately acquired by Cognition) by stating, “It would be unusual for us to sell Claude to OpenAI.”