Moonshot AI has accused Cursor of using its Kimi K2.5 model without adhering to licensing terms. Developer @fynnso identified the model ID for Cursor's Composer 2 as "kimi-k2p5-rl-0317-s515-fast," suggesting it incorporates Kimi K2.5. Yulun Du, Moonshot AI's head of pretraining, confirmed the similarity in tokenizers and questioned Cursor's compliance with licensing fees. Cursor's recent release of Composer 2 on March 19 highlighted performance improvements through continued pre-training and reinforcement learning but omitted any mention of Kimi K2.5. The model's modified MIT license requires commercial products with significant user bases or revenue to display "Kimi K2.5" prominently. Cursor, valued at $29.3 billion, has not yet responded to these allegations.