AIBRIEF
The Chinese lab calls Kimi K3 'open weight' rather than 'open source' and drops the modified MIT license (a permissive open source license) for a separate agreement trigger that fires when any Model as a Service business — i.e.
Moonshot AI published the weights for Kimi K3 on 27 July 2026: a 2.8-trillion-parameter model distributed as 1.56TB on Hugging Face, already live through seven OpenRouter providers at Moonshot's posted US$3 per million input tokens and US$15 per million output tokens. The weights are in the market. The license is the change.
Moonshot is calling the release "open weight," not "open source," and the K3 license has dropped the "modified MIT" label that K2 carried in July 2025. It introduces a separate-agreement trigger: any Model-as-a-Service business whose aggregate revenue plus affiliates exceeds US$20 million over any consecutive 12 months now needs a direct deal with Moonshot.
K2's earlier clause required prominent UI attribution of "Kimi K2" for commercial products or services with more than 100 million monthly active users or more than US$20 million in monthly revenue. K3 swaps attribution-as-condition for an annual revenue-gated negotiation with Model-as-a-Service businesses.
US$20 million in annual revenue is not a high bar for a serious Model-as-a-Service business, so the gate catches most resellers operating at scale. Downstream users routing through OpenRouter stay outside the new requirement.