Abstract
This article provides a comprehensive analysis of the criteria for determining inventiveness in China’s patent system. Based on the Patent Law of the People’s Republic of China and the Patent Examination Guidelines, inventiveness is a key substantive criterion for granting invention patents. The article systematically explains the legal definition of inventiveness, the two core criteria (prominent substantial characteristics and significant progress), and the widely followed “three-step” method in practice. It also discusses the assessment of “non-obviousness” in the third step of the “three-step” method and the key factors influencing the determination.
1. Core Concepts and Legal Basis of Inventiveness
In China’s patent legal framework, inventiveness is a key indicator of the technical height of an invention and directly relates to whether it can be granted a patent.
1.1 Legal Definition
According to Article 22(3) of the Patent Law of the People’s Republic of China, inventiveness requires that the invention has “prominent substantial characteristics” and “significant progress” compared to the prior art. This legal provision establishes two essential criteria for determining inventiveness.
- Prominent Substantial Characteristics: This refers to the “non-obviousness” of the invention. It assesses whether, to a person of ordinary skill in the relevant field (referred to as “the person of ordinary skill in the art” or “POSA”), the invention is obvious. If an invention is easily derived from the prior art by simple logical analysis, reasoning, or limited experimentation, it lacks prominent substantial characteristics. The Patent Examination Guidelines explicitly state that “non-obviousness” is the core criterion for determining inventiveness.
- Significant Progress: This criterion focuses on the technical effects and contributions of the invention. It requires the invention to produce beneficial technical effects, such as overcoming defects in the prior art, providing superior performance or lower-cost solutions, representing new technological trends, or opening new fields of technology.
1.2 Judgment Subject and Perspective
The judgment of inventiveness is conducted from the perspective of “the person of ordinary skill in the art.” This is a hypothetical legal concept referring to a person familiar with the relevant technical field, possessing all ordinary technical knowledge before the filing date, and capable of performing routine experimental methods. Examiners must evaluate objectively, avoiding the use of knowledge that became available after the filing date to avoid post-hoc reasoning.
2. Core Method for Inventiveness Determination: The “Three-Step” Method
To ensure the assessment of inventiveness is systematic, objective, and transparent, the Patent Examination Guidelines (specifically in Part II, Chapter 4) introduce and systematize the internationally recognized “three-step” method as a key tool and logical framework for examiners.
Step 1: Identify the Closest Prior Art
This is the foundation of the entire assessment. The closest prior art is the document(s) in the prior art that are most similar to the claimed invention in terms of technical field, the technical problem to be solved, technical effects, or purpose, or that disclose the most technical features of the claimed invention.
Selecting the closest prior art requires considering multiple factors. According to the 2023 revised Patent Examination Guidelines, examiners should prioritize prior art that addresses the technical problem of the invention when determining the closest prior art. This means that even if a prior art discloses more technical features, if it addresses a completely different technical problem, it may not be the most appropriate comparison document.
Step 2: Identify Distinctive Features and the Actual Technical Problem Solved
After identifying the closest prior art, the claimed invention’s technical solution is compared in detail to identify differences, i.e., “distinctive features.”
Based on these distinctive features, the actual technical problem solved by the invention is re-evaluated. The technical problem described in the application is the starting point, but not the final conclusion. Examiners must objectively re-determine the actual technical problem solved by the invention based on the technical effects achieved by the distinctive features.
Step 3: Determine Whether the Invention is Obvious to the Person of Ordinary Skill in the Art
This is the core and most challenging step of the “three-step” method, directly assessing the “non-obviousness” of the invention. Examiners must assess, from the perspective of the person of ordinary skill in the art, whether there is a “technical motivation” (Technical Motivation/Suggestion) in the prior art that would guide the person to make the improvements in the closest prior art, combined with other prior art or common knowledge, to solve the actual technical problem of the invention.
If such a technical motivation exists, and the success of the improvement is reasonably expected, the invention is considered obvious and lacks inventiveness. Conversely, if no such motivation exists, or if there is conflicting teaching (“technical prejudice”), the invention is generally considered non-obvious and possesses inventiveness.
3. Key Considerations in Assessing “Non-Obviousness”
In the third step of the “three-step” method, examiners consider various factors to determine whether a “technical motivation” exists.
3.1 Sources of Technical Motivation
Technical motivation is not generated out of thin air and typically arises from the following:
- Functional or Functional Similarity: If the distinctive features in another prior art serve a similar function or role as in the invention, the person of ordinary skill in the art may be motivated to apply them to the closest prior art.
- Technical Problem Correlation: If another prior art addresses a similar or related technical problem and provides corresponding technical means, this may constitute a motivation.
- Theoretical or Principle Complementarity: Basic principles, classic theories in textbooks, or common knowledge in technical manuals may provide motivation for combining different technical solutions.
3.2 Auxiliary Considerations (Positive Factors)
When the obviousness of an invention is difficult to determine, the Patent Examination Guidelines allow consideration of auxiliary or indirect factors that can support the inventiveness of the invention:
- Unexpected Technical Effects: If the technical effects achieved by the invention far exceed what a person of ordinary skill in the art could reasonably expect, such as performance improvements by orders of magnitude or new functions, this is a strong indicator of inventiveness.
- Overcoming Technical Prejudice: If the technical route of the invention contradicts the prevailing technical consensus or mainstream views of the field and successfully solves a problem, it typically indicates non-obviousness.
- Solving Longstanding Technical Problems: If a long-standing technical problem in the field has resisted solutions by many attempts, and the invention provides an effective solution, this supports inventiveness.
- Commercial Success: While commercial success does not directly equate to technical inventiveness, if it can be proven that the success is directly due to the technical features of the invention rather than marketing or pricing, it can serve as evidence of the invention’s technical superiority and market demand.
3.3 Common Obviousness Scenarios (Negative Factors)
The Patent Examination Guidelines also list common scenarios considered “obvious,” such as:
- Simple Application of Common Knowledge: Directly applying common knowledge in the field to solve a technical problem.
- Simple Combination Inventions: Simply combining known technical means or products without producing new synergistic effects.
- Simple Transplant Inventions: Directly transplanting a known technique to a functionally similar field.
- Simple Numerical or Range Selection: Making routine choices within a known numerical range without unexpected effects.
4. Conclusion
In summary, determining whether an invention possesses inventiveness, according to the China Patent Examination Guidelines, is a systematic, objective, and transparent process. It revolves around the two core criteria of “prominent substantial characteristics” (non-obviousness) and “significant progress” (beneficial technical effects). The “three-step” method provides a structured and logical framework for examiners to assess inventiveness. Examiners must adopt the perspective of “the person of ordinary skill in the art,” based on prior art before the filing date, avoiding post-hoc reasoning. The third step involves a thorough examination of whether the prior art provides a clear technical motivation. Auxiliary factors such as unexpected effects, overcoming technical prejudice, and solving long-standing problems support the assessment of inventiveness. A deep understanding of this complex system is crucial for successfully obtaining and maintaining Chinese invention patents.