从理论上来说，波特弱假说涉及双重外部性问题，即大气污染的负外部性和技术创新的正外部性，环境规制和知识产权保护合力才能予以切实彻底解决，而后者并没有得到普遍重视。本文认为，波特弱假说需要考虑知识产权保护强度。以SO_2排放控制技术为例，本文运采用2000-2013年省际省份面板数据，结合固定效应模型进行实证研究检验了知识产权保护对于波特弱假说的作用。结果发现，当知识产权保护较弱时，环境规制对大气科技创新具有呈现负向影响；。只有当知识产权保护较强时力度超过一定阈值时，环境规制才会对大气科技创新产生正向影响，波特弱假说成立。此外，环境规制和知识产权保护影响大气科技创新的交叉效应主要出现在企业，而非科研院所和个人，创新主体存在明显的差异性。

Theoretically, weak Porter Hypothesis involves dual externalities including negative externality of pollution and positive externality of scientific and technological innovation. Environmental regulation should be combined with protection of intellectual property to completely solve the dual externalities, but the protection of intellectual property has not been paid enough attention in practice. Taking SO2 emission abatement technology as an example, this paper collects provincial data during 2000-2013, and adopts fixed effect model to examine the effect of intellectual property protection on weak Porter Hypothesis. The results show that when intellectual property protection is weak, environmental regulation has a negative impact on innovation in atmospheric science and technology. When intellectual property protection level exceeds a certain threshold, environmental regulation begins to have a positive impact on the innovation, and weak Porter Hypothesis is established. Moreover, cross effect of environmental regulation and intellectual property protection on the innovation commonly appears in firms rather than universities or individuals.