In China, while patent infringement disputes are usually dealt by the People's Court, the determination of validity of a patent is within the exclusive jurisdiction of the China National Intellectual Property Administration (CNIPA). CNIPA includes the Patent Office and Trademark Office. The Reexamination and Invalidation Department of the Patent Office of CNIPA is responsible for handling patent invalidation procedures.

I. Trends of invalidation rates

  Statistics from were made on the invalidation decisions of invention and utility model patents over the past 11 years (2008-2018) to find out the trend of winning rates of petitioners in the invalidation procedures. See table 1.

Table 1. Statistics for Invalidation decisions

Type of decisions



Utility model

All claims invalid

2008-2018 in total












It can be seen from table 1 that for invention, invalidation decisions, in which all claims are invalidated in the years 2016-2018, obviously reduced compared to the average among years 2008-2018, while for utility model, the statistics of years 2016-2018 show only a small fluctuation around the average. So, it can be concluded that inventions indeed survive the invalidation procedure more easily in recent years than ever before, while utility models do not.

II. Reason analysis

Although there are no official explanations on such changes, it can be inferred that the essential merit of patents is more and more emphasized nowadays.

Specifically, it is way easier for petitioners who want to invalidate a utility model than to invalidate an invention to find evidences as reference documents to oppose novelty or inventiveness, because utility models did not undergo substantive examinations before being granted. And, as you may know, in Chinese invalidation procedure, besides of novelty and inventiveness, formal issues such as clarity, support by description, lack of essential features and non-statutory subject matter can also be served as reasons for invalidating a patent. So, in the past, many inventions were invalidated not because they lack novelty or inventiveness, but because they lack clarity, lack support by the description, go beyond the initial disclosure scope, and etc.

However, in recent years, as the Chinese government has increasingly advocated the protection of innovation, less and less formal issues appear in the invalidation decisions. Novelty and inventiveness are becoming the only key points to attract the Panel's attention. The inventions only have formal defects tend to be survived the invalidation procedure. That's the main reason why the invalidation rate for inventions drops in recent years while that for utility models remain substantially unchanged.

Besides, according to our experiences from years of practice, the current criteria of inventiveness also have some differences from the past, so that more inventions are maintained. This may be another reason why the invalidation rate drops for inventions.

As a criterion to evaluate the inventiveness of patents, the three-step test is traditional and common. The three-steps can be summarized as: step 1 to discover a closest prior art as a start, step 2 to determine characterizing features and their solved problem(s), and step 3 to decide whether they are obvious.

However, since the three-step test has its inherent shortcoming, which we will not discuss here, some other criteria have been explored and gradually widely used in recent years. Some prevailed ones include:

1. The prior art teaches away from the present invention;

2. The overall technical conception is different from the present invention; and

3. There is no motivation for those skilled in the art to move from the closest prior art to the present invention.

Other criteria include:

4. The invention solves a long-felt but unsolved technical problem;

5. The invention overcomes a prejudice;

6. The invention produces an unexpected technical effect; and

7. The invention achieves commercial success.

When any one of items 1-7 is fulfilled, the inventiveness can be established in spite of the three-step test. So, some inventions which could not pass the three-step test now are deemed as possessing inventiveness. This is another reason why more inventions can be survived.

III. What shall we do in the invalidation procedure

Since we have made clear the official policy, next, we will discuss if we are patentees, what shall we do when we face petitioner's attack in an invalidation procedure.

First, we had better avoid unnecessary amendments and observations when responding to formal issues raised by the petitioner. Often, the petitioners raise the formal issues actually in hope of obtaining our restrictive interpretation on claims scope, so that they can have the upper hand in the related infringement litigation. Since we know our patent is less likely invalidated by the non-fatal formal issues now, we may just make some brief response or even skip the formal issues in the written observations.

Second, if we evaluate that our patent cannot pass the three-step test, we may emphasize the other criteria.

For example, if we think the overall technical conception is different between the evidences and our patent, we may argue that although each of our characterizing features have been disclosed in different prior art documents, these characterizing features should not be separately considered, since they are correlative and inseparable to solve one technical problem in our patent and none of the prior art documents aims to solve the same technical problem. Once these characterizing features are successfully considered as a whole by the Panel, it will be hard for the petitioner to find one prior art document to disclose the whole technical solution, and thus inventiveness can be established.

For another example, if we think there is no motivation for those skilled in the art to move from the closest prior art to the present invention, we may point out that the closest prior art provided by the petitioner is in a different technical field or completely silent about the problem to be solved by our patent. In this case, the other prior art document is not necessarily to be found by those skilled in the art before they read our patent, because there is no motivation to search for the other prior art document to move toward our patent.

For still another example, in a real case, we alleged that the patent achieved commercial success. The petitioner showed the evidence disclosing product A as well as an evidence showing the only different part between product A and product B, which is protected by our patent, was common means in the art. Feeling hard to pass the three-step test, we provided testimony of a CEO of a company saying that his company used to purchase product A several years ago, but now only purchases product B with even higher price from a same supplier, just because product B has better performance, and that as far as he knows, companies in this field all turned to product B from product A. In this case, we managed to prove that our patent achieved commercial success and this success was directly brought by the technical advantage of our patent instead of other factors such as selling techniques or advertising.

Third, we may provide evidences actively, although the burden of proof is on the petitioner. For example, to argue that the characterizing feature is not common means in the art, we may submit text books or design manuals to prove "anti-common knowledge". In a past real case, we once faced the petitioner's assertion that the gear coupling is common means in the art. Then we provided some mechanical design manuals to prove that although gear coupling was known in the art, it was not suitable for high speed scenario which is exactly our patent is used for. Our evidences played an important role in that case.

In summary, it is indeed easier for patentees to survive the invalidation procedure now, because formal defects in the drafting are no longer fatal, and criteria for evaluating the true merit of a patent is becoming diversification in China. If we realize this situation and fully understand the reason, we will be able to advisably cater to this trend to maintain our patent right.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.