Chinese patent inventiveness provisions are primarily modeled after the European patent system and are quite similar to European inventiveness criteria and assessment methods, whereas they differ significantly from those in the United States. Additionally, since the U.S. does not have utility model patents, this article focuses on the differences and similarities in the legal provisions and assessment methods for inventiveness in China and the U.S. regarding inventions.
1. Legal Provisions on Inventiveness in Chinese and U.S. Patent Law
1.1 Legal Provisions on Inventiveness in Chinese Patent Law
According to Article 22, Paragraph 3 of the Chinese Patent Law, “Inventiveness means that, compared with the prior art, the invention has prominent substantive features and represents a notable progress.” Based on this provision, the assessment of inventiveness requires considering both “prominent substantive features” and “notable progress.”
The “Patent Examination Guidelines,” Part II, Chapter 4, provide detailed definitions of inventiveness from the perspectives of prior art, prominent substantive features, notable progress, and the person skilled in the art.
Specifically, Section 2.2 states, “An invention has prominent substantive features if, compared with the prior art, it is non-obvious to a person skilled in the art. If the invention can be derived by a person skilled in the art from the prior art through logical analysis, reasoning, or limited experimentation, then the invention is obvious and does not possess prominent substantive features.” Section 2.3 states, “An invention represents notable progress if it yields beneficial technical effects compared with the prior art. For example, the invention overcomes shortcomings and deficiencies of the prior art, provides a different technical solution to a technical problem, or represents a new trend in technological development.”
According to the above provisions of the “Patent Examination Guidelines,” assessing the “prominent substantive features” of an invention involves determining the non-obviousness of the invention compared to the prior art. Assessing the “notable progress” involves determining the beneficial technical effects of the invention.
On the other hand, Section 2.3 of the same guidelines also lists “providing a different technical solution to a technical problem” as a scenario where an invention has beneficial technical effects, thereby extending the concept of beneficial technical effects to include different technical solutions compared to the prior art (further clarified in Section 3.2.2 of the same chapter, where the technical effects can essentially reach the level of the prior art). Thus, in practice, assessing inventiveness generally involves primarily determining the non-obviousness of the invention relative to the prior art, with technical effects used as auxiliary criteria when non-obviousness is difficult to assess. Additionally, there is a view that invention applications and patents typically have beneficial technical effects, so the main focus in assessing inventiveness in patent applications and litigation is whether the invention is non-obvious compared to the prior art.
1.2 Legal Provisions on Inventiveness in U.S. Patent Law
In the United States, 35 U.S.C. § 103 stipulates that “A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains.” Thus, U.S. patent law directly uses “non-obviousness” as the standard for assessing inventiveness.
In summary, while the legal terminology for inventiveness differs between China and the U.S., both essentially focus on the “non-obviousness” of the invention relative to the prior art.
2. Methods for Assessing “Non-Obviousness” in China and the U.S.
Although both China and the U.S. focus on “non-obviousness” as the core criterion for assessing inventiveness, their specific assessment methods differ significantly. Below is a detailed analysis.
2.1 Methods for Assessing “Non-Obviousness” in China
In China, the “Patent Examination Guidelines,” Part II, Chapter 4, Section 3.2.1.1, specifies a three-step method for assessing the non-obviousness of a claimed invention compared to the prior art:
- Determine the closest prior art.
- Determine the distinguishing features of the invention and the technical problem actually solved by the invention.
- Assess whether the claimed invention would have been obvious to a person skilled in the art.
Clearly, China uses a “problem-solution” approach similar to European patent law.
For determining the technical problem actually solved by the invention, Section 3.2.1.1 of the “Patent Examination Guidelines” emphasizes that the technical problem should be determined based on the technical effects achieved by the distinguishing features in the claimed invention. This technical problem may differ from the one described in the specification. As a principle, any technical effect described in the application can serve as a basis for redefining the technical problem, as long as it can be understood by a person skilled in the art from the disclosure of the application.
For the third step, Section 3.2.1.1 of the same guidelines specifies that it is necessary to determine whether there is a technical motivation in the prior art to apply the distinguishing features to the closest prior art to solve the technical problem (i.e., the actual technical problem solved by the invention). This motivation should prompt a person skilled in the art to improve the closest prior art and achieve the claimed invention.
However, the three-step method prescribed in the “Patent Examination Guidelines” can sometimes be misapplied in practice, leading to a mechanical combination of different pieces of prior art to evaluate the obviousness of the invention’s technical solution. To address this issue, the 2019 revision of the “Patent Examination Guidelines” added the following content to Section 3.2.1.1: “For technical features that functionally support each other and have an interactive relationship, their relationship and the technical effect achieved by their combination in the claimed invention should be considered as a whole.”
This addition emphasizes the principle stated in Section 3.1 of the same chapter that an invention should be considered as a whole during the inventiveness assessment. It aims to ensure that, when determining the distinguishing features and the actual technical problem solved by the invention, the examiner considers both the individual roles of the technical features and their interrelationship and contribution to the technical effect, focusing on the overall technical solution provided by the invention.
Additionally, regarding the “technical motivation” in the third step, the Supreme People’s Court of China provided guidance in a judgment on December 2, 2022 (case number 2022 Zui Gao Fa Zhi Xing Zhong 316) stating that the invention’s concept should also be considered when determining technical motivation in the prior art.
In this case, although the involved patent and comparison document 1 have several corresponding components, there are significant differences in the specific structure, mutual position relationship, and technical effects of each component, indicating that they adopt different inventive concepts and that the overall technical solutions differ greatly. The Supreme People’s Court elaborated on this difference in its second-instance judgment: an inventive concept refers to the technical improvement idea proposed by the inventor to solve the faced technical problem during the creation of the invention, which determines the path of technical improvement and the composition of the final technical solution. When using the “three-step method” to assess whether an invention possesses inventiveness, if there is a significant difference in the inventive concepts between the invention and the closest prior art, it is usually unlikely that a person skilled in the art would have the motivation to improve the closest prior art to obtain the invention; if there is a significant difference in the inventive concepts between the prior art documents used as references, it is usually difficult for a person skilled in the art to find the technical motivation to combine two prior art documents with different inventive concepts to obtain the invention. Through this case, the Supreme People’s Court clarified the important role of inventive concepts in determining technical motivation.
It is evident that China’s method for judging the obviousness of patents is also continually being refined and moving towards a more objective and reasonable direction.
2.2 Methods for Assessing “Non-Obviousness” in the U.S.
In comparison, since the U.S. adopts case law, the specific methods for determining obviousness under 35 U.S.C. § 103 are primarily derived from various court rulings. Specifically, in 1966, the U.S. Supreme Court in Graham v. John Deere Co. established four factors for evaluating obviousness: (1) determining the scope and content of the prior art, (2) ascertaining the differences between the claimed invention and the prior art, (3) resolving the level of ordinary skill in the pertinent art, and (4) considering secondary considerations, such as commercial success, long-felt but unsolved needs, the failure of others, and unexpected results. The USPTO and courts should follow these Graham factors, including secondary considerations, to determine the obviousness of an invention. The Graham v. John Deere Co. case’s method became the basic approach for current obviousness examination.
Subsequently, in 1982, the U.S. Court of Appeals for the Federal Circuit (CAFC) established the TSM (teaching-suggestion-motivation) test through case law, thereby enhancing the operability of patent examination and litigation practice. The TSM test requires meeting the following conditions: there must be some teaching, suggestion, or motivation in the prior art itself or generally available knowledge to modify or combine the teachings of different prior art references; there must be a reasonable expectation of success; and all claim limitations must be taught or suggested by the prior art. Thus, the TSM test demands that the prior art provide clear guidance or motivation for modification or combination to deem an invention obvious.
While the TSM test is more practical, it can become overly stringent and rigid, leading to numerous patents of low inventiveness, resulting in patent proliferation. In 2007, the U.S. Supreme Court in KSR v. Teleflex criticized and corrected the overly rigid application of the TSM test by the CAFC. The Supreme Court reaffirmed the importance of the Graham factors and determined that a person skilled in the art has “ordinary creativity” and can use common sense to improve or combine prior art. The motivation for improvement or combination does not necessarily have to come from explicit disclosures in the prior art. The Court stated, “When a work is available in one field of endeavor, design incentives and other market forces can prompt variations of it, either in the same field or in a different one. If a person of ordinary skill can implement a predictable variation, § 103 likely bars its patentability,” even if there is no explicit teaching, suggestion, or motivation to combine the known elements in the prior art. The KSR case thus relaxed the rigid framework and raised the inventiveness bar by allowing the use of common sense or known methods to improve or combine prior art, becoming a new milestone in the U.S. standard for evaluating inventiveness. It has since been frequently cited in subsequent patent applications and litigations.
2.3 Similarities and Differences in Methods for Assessing “Non-Obviousness” in China and the U.S.
Comparing the “non-obviousness” assessment methods of China and the U.S., it is clear that while the U.S. combines the Graham factors with the TSM test, its assessment steps broadly resemble China’s three-step method. For instance, both require first identifying the prior art, then determining the differences between the prior art and the claimed invention, and finally assessing whether these differences would be obvious to a person skilled in the art.
However, there are differences in the last step of “assessing whether the combination of the distinguishing features would be obvious to a person skilled in the art.” In China’s “problem-solution” approach, when determining whether a person skilled in the art would be motivated to improve the closest prior art, the “technical problem” acts as a guiding factor. It directs the examiner or judge to assess whether the technical means defined by the distinguishing features solve the same technical problem in the prior art. Usually, if the technical means defined by the distinguishing features in the prior art solve the same technical problem, it is considered that the prior art provides the motivation for combining the features.
In contrast, the U.S. method revised by the KSR case does not use the “technical problem” as a link. It focuses on whether the prior art provides clear guidance or motivation for modifying or combining references, or whether common sense or known methods can improve or combine the prior art. This guidance or motivation does not need to solve the same technical problem addressed by the claimed invention but must be evident in the prior art or derivable through common sense or known methods.
In practice, patent applicants often encounter situations where the same invention, based on identical claims and prior art references, is granted in the U.S. but deemed non-obvious and unpatentable in China. Similar discrepancies arise in patent invalidation lawsuits. These differences stem from the varying focal points of the assessment methods, with China emphasizing solving the same “technical problem” in the prior art and the U.S. focusing on clear guidance or motivation for modification or combination in the prior art.
Additionally, the “Patent Examination Guidelines” in China also include auxiliary factors similar to those in the Graham v. John Deere Co. case. For instance, Section 5 of Chapter 4 in the “Patent Examination Guidelines” lists additional factors for considering inventiveness, such as:
- The invention solves a long-felt but unsolved technical problem.
- The invention overcomes technical prejudice.
- The invention achieves unexpected technical effects.
- The invention has achieved commercial success.
Comparing these factors reveals similarities with the secondary considerations in the Graham factors, indicating that despite differences in primary assessment methods, the auxiliary factors for non-obviousness (or inventiveness) judgment share many commonalities between China and the U.S.
3. Conclusion
In conclusion, both Chinese and U.S. patent systems and practices strive to assess inventiveness from the perspective of a person skilled in the art, using prior art as a starting point to reconstruct the invention process and determine whether inventive labor was involved. However, due to various reasons, differences in inventiveness standards and assessment methods remain between China and the U.S., potentially leading to divergent outcomes.
As economic and technological exchanges between countries continue to grow, inventors and companies hope for uniform patent inventiveness standards worldwide. However, foreseeable differences are likely to persist for a long time. Therefore, continuously understanding and researching the differences in patent systems, particularly between China and the U.S., is beneficial for effectively navigating the complexities of patent protection arising from these differences and achieving better global patent strategies.