The world's biggest open-source model ships under a licence written for it
Moonshot's Kimi K3 — 2.8 trillion parameters, billed as the largest open-source model — released its weights on 27 July under the "Kimi K3 License". Not Apache 2.0, not MIT: a bespoke instrument named after the model it governs.
Count the licences now attached to things called open weights: Apache 2.0, MIT, community licences with acceptable-use appendices and user thresholds, revenue-share grants, and now per-model bespoke instruments. That is five legal regimes sharing one phrase, and the phrase has stopped carrying information.
A licence named after its model is the clearest possible signal that terms are being set per release rather than adopted from a standard. It means every deployment decision requires reading a document that governs exactly one artefact and has no case law, no community interpretation, and no precedent.
The scale makes it consequential rather than academic. At 2.8 trillion parameters, K3 is the largest openly released model, and the organisations with infrastructure to run it are precisely the ones whose legal departments will not accept an unreviewed bespoke grant.
The pattern is now unmistakable across three weeks: Alibaba attached a revenue share, Meta moved the other way to Apache 2.0, and Moonshot wrote its own. Openness of weights and openness of terms have fully decoupled, and only the second one determines whether you can ship.
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