Googlers finally get Claude, but only inside Antigravity

Google has opened Anthropic’s Opus 5 to engineers across the company for internal work. Business Insider reported the change on September 15, citing two employees, and a Google spokesperson confirmed it. The access comes with two conditions: Claude runs only inside Antigravity, Google’s internal version of its development platform, and every user gets a quota.

Until now, Google barred most employees from outside coding tools such as Claude Code and OpenAI’s Codex and expected them to build with Gemini. There were exceptions. Teams within Google DeepMind have had Claude for some time, and some employees secured it for high-priority engineering projects, three people with knowledge of the matter said, per Business Insider. So the change opens up who gets Claude, not which tool they reach it through: staff get the model inside Google’s own environment, not Claude Code itself.

Pressure from engineers built up beforehand. Despite recent gains from its Flash 3.8 model, Google still trails Anthropic and OpenAI on coding, the outlet reports, and that has left some Googlers frustrated with Gemini’s limitations. Business Insider previously reported that the frustration grew because Claude stayed limited to select teams even as the company pushed staff to show they were using AI to be more productive.

Amazon went through the same thing earlier this year. It also gave employees access to Claude after staff complaints, and started letting them use Claude Code and Codex.

Google is also one of Anthropic’s backers. In April it announced plans to invest up to $40 billion in the company: $10 billion now and another $30 billion tied to performance milestones, according to TechCrunch and CNBC. Anthropic in turn relies heavily on Google Cloud for chips and infrastructure, TPUs included, TechCrunch reported. In September the Financial Times put a $200 billion figure on the Wall Street financing Google has assembled around Anthropic.

The spokesperson tied the internal setup to what Google sells outside: “Engineers have access to select third-party models in Antigravity, which is aligned with our external Antigravity enterprise offering.” Google’s cloud division already offers Claude models to customers, CNBC reported, while Gemini competes with Anthropic for the same AI customers.

Inside Google, the spokesperson said, Claude comes with per-user quotas and is meant to supplement Gemini, not replace it. “Gemini remains our primary and foundational model for internal development, with third-party models available on a quota to support specialized use cases.”