SourcesArcee Trinity Large — Open 400B Sparse MoE 13B ActiveArcee AI·high signalXBlueskyLinkedInCopy linkLargest open-weight US model. 400B total, 13B active. 87.2 MMLU. Apache 2.0. Trained in 33 days on 2048 B300s for ~20M.SourceSource pageArcee AI↳ Follow the threadPolicy dependency / Stack layerAltman tells OpenAI staff the company is open to slowing frontier development and wants other labs to matchReuters / Bloomberg (via r/singularity)Stack layer / ContrastCohere Released an Open-Weight 218B Translation Model That Beats DeepL and Google Translate on WMT26Hugging Face (Cohere Labs)Policy dependency / Stack layerAltman Tells OpenAI Staff the Company Is Open to Slowing Frontier AI, and OpenAI Asked Congress Whether a Coordinated Slowdown Would Break Antitrust LawBloombergStack layer / ContrastTwo agent IDEs now ship the same sentence, and one of them has more open PRs than open issuesGitHubStack layer / ContrastSakana AI Ships Fugu Max and Fugu Ultra v2, an Orchestrator That Routes Each Task to the Leanest Model, at $2/$6 per Million TokensSakana AIStack layer / ContrastCognition ships SWE-2 on a Kimi K3 base: 92.8% on Terminal-Bench 2.1, and within a point of Fable 5.1 on FrontierCode at 64% lower costCognitionStack layer / Contrasthumans& Released Persimmon, a 550B User Simulator That Fools LLM Judges About 20% of the Time in Group Chatshumans&Stack layer / ContrastPageIndex reached 35,621 stars arguing RAG should not use vectors at allGitHub