Insights from the SPC Novartis Judgment: Inventive Step Assessment in China
Date: 5 June 2026
【Volume 172】
In the landmark administrative judgment “(2019) Zui Gao Fa Zhi Xing Zhong No. 235” (the Novartis case), the Supreme People’s Court (SPC) of China provided an authoritative interpretation of “reasonable expectation of success” in assessing the inventive step of a patent. While China adopts the “three-step method” for evaluating inventive step, the determination of a “reasonable expectation of success” involves the greatest degree of subjective discretion throughout the analysis. In fields with relatively high unpredictability, particularly in chemistry, pharmaceuticals, and biotechnology, “reasonable expectation of success” serves as a crucial benchmark for determining whether technical motivation exists. In this pivotal ruling, the SPC pointed out that, in the chemical and biotechnology fields, establishing a reasonable expectation of success does not require “certain success” or even “a high probability of success”. Rather, if a person ordinarily skilled in the art, based on the prior art and experimental conditions before the filing date, would have considered the attempt worth making and would not have abandoned such attempt, a reasonable expectation of success may be established.
Case Facts
Novartis was the plaintiff and patentee of the invention patent titled “Pharmaceutical Compositions Comprising Valsartan and NEP Inhibitors” (hereinafter, the disputed patent). Dai Jinliang filed an invalidation request with the China National Intellectual Property Administration (CNIPA) seeking invalidation of the disputed patent for lack of inventive step. CNIPA declared the disputed patent invalid. Dissatisfied with the decision, Novartis initiated judicial proceedings on the grounds of “no reasonable expectation of success” and “incorrect identification of the closest prior art.” In the second-instance proceeding, the SPC dismissed the appeal and upheld CNIPA’s invalidation decision.
Novartis’s Arguments
Novartis argued that a person ordinarily skilled in the art would not have had a reasonable expectation of success with respect to the combined technical solution for the following reasons:
1. AII antagonists and NEP inhibitors exhibit opposite and complex physiological effects;
2. The prior art acknowledged that their mechanisms of action were unpredictable and did not provide a clear conclusion; and
3. The pharmaceutical combination contained “non-working ones” by which antihypertensive effects could not be achieved.
Opinion of the court
The SPC held that:
1.The closest prior art had already disclosed that a combination of an AII antagonist and an NEP inhibitor could be used to treat hypertension, and further disclosed key information such as experimental methods, conclusions, administration methods, and dosages, thereby providing clear technical motivation to a person ordinarily skilled in the art.
2.Where the prior art has already provided functional guidance for categorized pharmaceutical combinations and there remains room for selection of specific drugs, the fact that development of a specific combination does not have “certainty of success” is insufficient to prove that a person ordinarily skilled in the art would have abandoned the attempt.
3. Defenses, such as complex mechanisms of action, existence of unpredictable factors, and existence of “non-working combinations” by which technical effects cannot be achieved, are all insufficient to negate a reasonable expectation of success.
Wisdom Analysis and Suggested Strategies
This case established an important standard for assessing inventive step of patents in the chemical and pharmaceutical fields: where “the prior art provides directional guidance” and “there exists room for routine selection,” a “reasonable expectation of success” is established. Positioned between “technical feasibility” and “certainty of success,” the standard does not require 100% success. Rather, it is sufficient that there is “motivation to try, guidance to follow, and a path to pursue” for a reasonable expectation of success to be recognized.
More specifically, assessment of inventive steps in the chemical and biotechnology fields still follows the “three-step method” (the first step is identifying the closest prior art, the second step is determining distinguishing features and the actual technical problem, and the third step is assessing obviousness). “Reasonable expectation of success” is a factor considered in the third step (i.e., the assessment of obviousness) and is used to determine whether a person ordinarily skilled in the art would have had motivation to improve the prior art and whether technical teaching existed. The applicable standard takes “necessity of attempting” as the core consideration and does not need “certainty of success” or “high probability of success.” Instead, if a person ordinarily skilled in the art, based on the prior art and experimental conditions before the filing date, would have considered the attempt worth making and would not have abandoned such attempt, a reasonable expectation of success is established.
In pharmaceutical and chemical cases, patentees often argue inventive step on grounds such as “unpredictability,” “existence of non-working subrange,” or “opposing mechanisms.” In response, a party asserting invalidity may rely on the rule established in the Novartis case: “unpredictability does not mean that attempts cannot be made,” and “where guidance exists, expectation exists.” If a person ordinarily skilled in the art would have been motivated to start from the closest prior art and could reasonably expect to obtain the patented technical solution, the patent may be found to lack inventive step.
Exceptionally, even where a reasonable expectation of success exists, inventive step may still be recognized if verification of the technical solution requires inventive effort or yields unexpected technical effects. Accordingly, the following defense strategies may be adopted by patentees:
1. Submit complete research and development records (e.g., experimental protocols, failed data, and screening processes) to demonstrate that moving from the prior art to the disputed patent required extensive screening, non-routine experimentation, and non-obvious adjustments.
2. Submit comparative experimental data to demonstrate that the disputed patent achieved unexpected technical effects (e.g., synergistic enhancement, improved stability, or effects far superior to those of individual components).
3. Emphasize unpredictability in the chemical and biotechnology fields: even if motivation to try existed, inventive step should still be recognized where the verification process demands inventive effort.
Through a series of representative decisions, the SPC has unified standards for assessing inventive step in the chemical and pharmaceutical fields. For enterprises, mastering the essence of “reasonable expectation of success” not only enables precise attacks against competitors in invalidation proceedings, but also helps strengthen defensive strategies in patent portfolio planning.
