International clean technology diffusion is essential to mitigate and adapt to climate change, while fast and optimal diffusion can be prevented by the paywall of patents. This article explores the deficiency in clean technology diffusion caused by the legal fragmentation and rule complex of international environmental law and intellectual property law. It systematically examines three pathways to foster international clean technology diffusion through: restriction of intellectual property, including imposing external restraints in environmental law; striking internal balancing in maximizing TRIPS flexibilities; and keeping the status quo. It argues that treaty pathways may not work, and an operable pathway to promote clean technology diffusion is to maximize and consolidate TRIPS flexibilities in national laws. This option challenges the popular proposal of a “Doha-like” declaration on TRIPS and climate change due to the paralyzed multilateral trade mechanism, asymmetrical negotiation power of developing countries, prolonged negotiation process, and categorization problem in treaty negotiations.

国际清洁技术扩散对于缓解和适应气候变化至关重要，而专利的付费墙可以防止快速和最佳的扩散。本文探讨了国际环境法和知识产权法的法律碎片化和规则复杂性导致的清洁技术扩散的不足。它系统地研究了促进国际清洁技术传播的三种途径：限制知识产权，包括在环境法中施加外部限制；在最大化 TRIPS 灵活性方面实现内部平衡；并保持现状。它认为条约途径可能行不通，促进清洁技术传播的可行途径是在国家法律中最大化和巩固 TRIPS 灵活性。