Chinese AI startup Moonshot has unveiled Kimi K3, a 2.8 trillion-parameter model that is the world’s largest open-weight AI system. This launch comes a month after Anthropic’s Fable and Mythos models were withdrawn by the U.S. government due to security concerns.

Competing with US Rivals

Kimi K3 delivers performance approaching that of US giant Anthropic’s frontier Fable model. The model features a 1 million-token context window, allowing it to process and retain substantially more information than earlier generations in a single prompt.

Moonshot said Kimi K3 performed competitively with Fable 5 and substantially outperformed OpenAI’s Opus 4.8, GPT 5.6 Sol, and GPT 5.5 in terms of GPU kernel optimization. The model has also posted strong results in third-party evaluations.

Accelerating Release Cycles

Chinese AI firms are accelerating their model release cycles as the global AI race intensifies. The shift follows the debut of Z.ai’s GLM-5.2, which scored near top US closed-source models on benchmark tests, undermining a consensus among Western analysts that Chinese AI models were at least six months behind.

Original reporting: Appleton, WI News Feed (HLL/CB) — read the source article.