HKU Jockey Club Enterprise Sustainability Global Research Institute
World-Class Hub for Sustainability
Tao Shu | Fei Xie | Song Zhang | Wenrui Zhang
When Science and Technology Collide with Politics: Patent Examiner Ideology and Green Innovation
Apr 28, 2026
Key Takeaways
- Research Question: The study examines whether the political ideology of patent examiners influences the evaluation of green technology patents (green innovation), thereby distorting inventors’ and firms’ innovation incentives and altering the trajectory of scientific and technological development.
- Data and Method: Using more than 5 million non-provisional U.S. patent applications filed between 2001 and 2023, the authors link U.S. Patent and Trademark Office (USPTO) records on patent examiners with voter registration data to identify the political affiliation of individual examiners.
- Findings
- Republican examiners reject green patent applications 2 percentage points more often than independent examiners, representing a 7.7% increase relative to the average rejection rate.
- The partisan gap in rejection rates for green patent applications is concentrated in climate-change-related technologies and widens during Republican presidential administrations and periods of heightened political polarization over climate change.
- Green patents approved by Republican examiners do not exhibit higher scientific or economic value than those approved by other examiners, providing no evidence that the higher rejection rate of Republican examiners reflects stricter quality standards.
- When rejecting green patent applications, Republican examiners are more likely to invoke Section 101 (subject-matter eligibility), which involves greater discretion and is more difficult for applicants to address through amendments or appeals.
- Rejections by Republican examiners generate a “chilling effect” on future green innovation, reducing subsequent green patent filings by inventors and firms.
- Implication: The results suggest patent examiners’ political ideology can redirect R&D resources and influence the trajectory of environmentally important technologies, highlighting the importance of politically neutral evaluation processes within technocratic institutions.
Source Publication:
Shu, T., Xie, F., Zhang, S., & Zhang, W. (2025). “When Science and Technology Collide with Politics: Patent Examiner Political Ideology and Green Innovation.” SSRN Working Paper.
Background and Research Question
Patent systems rely on objective legal and technical standards to evaluate new technologies. In practice, however, patent examiners have substantial discretion in interpreting patentability criteria and determining whether an invention meets those standards. Because these bureaucratic decision-makers hold different political beliefs, their ideological preferences may influence how they assess applications, particularly when reviewing politically salient technologies.
Green innovation provides a setting in which such ideological effects may arise. Environmental technologies, especially those addressing climate change, have become highly politicized in the United States. If examiner ideology influences patent evaluation, the patent system may significantly shape the incentives for developing socially valuable technologies. This study investigates whether patent examiners’ political ideology influences the approval of green patent applications and, in turn, subsequent green innovation by inventors and firms.
Data and Methodology
The study analyzes more than 5 million non-provisional utility patent applications filed with the USPTO between 2001 and 2023. The authors combine patent examination records from the USPTO’s Patent Examination Research Dataset (PatEx) with examiner information from the U.S. Office of Personnel Management and voter registration data from L2 to identify the political affiliation of individual examiners.
The empirical strategy exploits the quasi-random assignment of patent applications to examiners within specialized technological units at the USPTO. Because applications are assigned largely independently of their underlying quality, this setting allows the authors to examine whether rejection decisions vary systematically with examiners’ political ideology while accounting for other factors that may affect patent approval outcomes.
Findings
The results reveal a clear ideological divide in the evaluation of green innovation. Republican examiners are about 2 percentage points more likely to reject green patent applications than independent examiners, representing a 7.7% increase relative to the average rejection rate. This disparity is stronger for technologies directly related to climate change than for other environmental technologies, such as pollution control, and becomes more pronounced during Republican presidential administrations and periods of heightened political polarization over climate change.
The study then examines whether the higher rejection rate among Republican examiners reflects stricter evaluation standards. If so, the green patents they approve should be of higher quality. However, the results do not support this explanation: green patents approved by Republican examiners do not receive more citations or generate higher economic value than those approved by other examiners.
The study further finds no significant differences between Republican and other examiners in first-action allowances, whereas applicants are less likely to amend and resubmit after rejections by Republican examiners. One possible explanation is that Republican examiners more often invoke Section 101 of U.S. patent law (subject-matter eligibility) when rejecting green patents. Section 101 determinations involve considerable discretion and are more difficult for applicants to address through amendments or appeals, making these rejections harder to overcome.
These examination outcomes also have broader consequences for subsequent innovation. Inventors and firms that receive a rejection from a Republican examiner are less likely to continue pursuing green innovation: over the following three years, affected inventors filed about 14% fewer green patent applications, while public firms reduced green patent filings by around 7.7 percent.
Implications
The study shows examiners’ political ideology affects the evaluation of green patent applications. Republican examiners are more likely to reject green patents without approving higher-quality ones. These differences arise in part from the use of more discretionary grounds for rejection that are harder for applicants to address, reducing the likelihood of amendment and subsequent green patent applications by inventors and firms. Economically, the study estimates that ideological distortions in the patent review process have resulted in roughly 10,000 additional rejected green patent applications and at least $20 billion in lost economic value for public firms. The analysis also finds economically meaningful declines in subsequent innovation, with green patenting decreasing by about 14.1% for affected inventors and about 7.7% for public firms.
More broadly, the findings highlight the role of institutional gatekeepers in shaping the evolution of innovation ecosystems. When outcomes in the patent review process become less predictable or more difficult to address, inventors and firms may be less willing to pursue new innovations, particularly in politically salient fields such as climate innovation. Such responses can slow technological progress in economically and socially important areas.
These findings provide new insights into the importance of maintaining political neutrality in technocratic decision-making. Greater transparency and clearer guidance in applying discretionary legal grounds, particularly Section 101, may help ensure technologies in politically or ideologically sensitive areas are assessed consistently and based on their scientific and technological merits.