Rivals OpenAI, Anthropic PBC, and Alphabet Inc.’s Google have begun working together to try to clamp down on Chinese competitors extracting results from cutting-edge US AI models to gain an edge in the global AI race. Only a handful of countries—the United States, the Netherlands and Japan—have specialised tools required to produce AI chips.The firms are sharing information through the Frontier Model Forum, an industry non-profit that the three tech firms founded with Microsoft Corp. in 2023, to detect so-called adversarial distillation attempts that violate their terms of service, according to people familiar with the matter. The rare collaboration underscores…