Abstract: The rise of domestic large language models represented by DeepSeek marks that open-source innovation is gradually becoming a strategic engine driving the development of artificial intelligence. In the evolution of large model technology, the ontology attributes have shifted from deterministic logical code to parameter matrices representing probability distributions, thereby triggering a paradigm shift from “code open-source” to “weight openness.” The adoption of a weight openness model by Chinese large models is a strategic consideration based on three dimensions: technology ecosystem diffusion, security sovereignty defense, and legal rule negotiation. It aims to hedge against computing power restrictions and accelerate the adaptation of domestic chips through “intellectual spillover.” Although open weighting has accelerated the diffusion of technology, it has caused a deviation from the traditional open-source spirit in terms of legal attributes and clause design, falling into a predicament where name and reality do not match. To address these limitations, building a Chinese-characteristic open weighting ecosystem requires multidimensional coordination in legal regulation, infrastructure, and community governance, transforming open weighting into inclusive infrastructure that empowers industrial upgrading while ensuring technological independence and controllability.