A Danish Company v. China National Intellectual Property Administration and a Pharmaceutical Company: Administrative Dispute over Invalidation of an Invention Patent

— Determination of whether supplementary experimental data submitted by the patentee in invalidation proceedings to prove that the invention in suit has better effects than the prior art can serve as evidence for assessing the inventiveness of the patent

Keywords: administrative; patent-related administrative case; invalidation of invention patent; inventiveness; supplementary experimental data; technical effect; admissibility of evidence

Basic Facts

A Danish company is the patentee of the invention patent No. 20068000****.6 titled "Acylated GLP-1 compounds" (hereinafter the "Patent in Suit"). A pharmaceutical company requested the China National Intellectual Property Administration (CNIPA) to declare the Patent in Suit invalid in its entirety, mainly on the grounds that claims 1-6 of the Patent in Suit lacked inventiveness and did not comply with Article 22, paragraph 3 of the Patent Law. In response, the Danish company submitted two sets of supplementary experimental data. The first set was mainly intended to prove that the activity assay experiments relating to Si*tide in claim 1 of the Patent in Suit had been completed before the priority date; the second set was comparative experimental data between Si*tide in claim 1 of the Patent in Suit and Li*tide, which is prior art.

On August 24, 2022, CNIPA made the challenged decision, holding that the technical effect of Si*tide in the claims having a longer duration of action, which the supplementary experimental data submitted by the Danish company were intended to prove, could not be derived from the contents of the original application documents. A person skilled in the art could easily arrive at the technical solution of the Patent in Suit on the basis of the prior art, and the technical effect was also foreseeable by a person skilled in the art; therefore the Patent in Suit lacked inventiveness. Accordingly, it decided to declare the Patent in Suit invalid in its entirety.

The Danish company argued that the following technical effects of claim 1 of the Patent in Suit could be derived from the description of the patent: first, a duration of action of at least 24 hours after administration to db/db mice at a dose of 30 nmol/kg; second, a half-life of more than 60-70 hours in minipigs. Given that the above technical effects could be derived from the description, the experimental data subsequently submitted by the Danish company could further prove that Si*tide of claim 1 of the Patent in Suit had unexpected technical effects in both of the above respects compared with the closest prior art, Li*tide. The challenged decision improperly refused to accept the experimental data subsequently submitted by the Danish company. It therefore filed a lawsuit with the Beijing Intellectual Property Court, requesting that the challenged decision be revoked and that CNIPA be ordered to make a new examination decision.

On November 6, 2023, the Beijing Intellectual Property Court rendered Administrative Judgment (2023) Jing 73 Xing Chu No. 1324, revoking the challenged decision and ordering CNIPA to make a new examination decision.

After the judgment was pronounced, the pharmaceutical company was dissatisfied and filed an appeal. On December 26, 2025, the Supreme People's Court rendered Administrative Judgment (2023) Zui Gao Fa Zhi Xing Zhong No. 1282: the appeal is dismissed and the original judgment is upheld.

Reasons for the Judgment

The main issue in dispute in this case is whether the experimental data supplementarily submitted by the Danish company can serve as evidence for assessing the inventiveness of the Patent in Suit.

Article 22, paragraph 3 of the Patent Law of the People's Republic of China (as amended in 2000) provides: "Inventiveness means that, as compared with the technology existing before the date of filing, the invention has prominent substantive features and represents notable progress, and the utility model has substantive features and represents progress." (Article 22, paragraph 3 of the Patent Law as amended in 2020 retains this provision.) Accordingly, the inventiveness of a patented invention comprises two aspects: first, in terms of technical constitution, the invention is clearly and essentially different from the prior art and is not obvious to a person of ordinary skill in the technical field to which the invention pertains; second, in terms of technical effect, the invention can produce beneficial technical effects compared with the prior art. Where the patentee proves the inventiveness of the patent by experimental data, the experimental data must in principle be "derivable from the original application". Where the patentee submits supplementary experimental data after the filing date to prove the technical effects of the patent, the data must be consistent with the technical effects already recorded in the original description; entirely new effects not mentioned in the original application cannot be added afterwards. As to supplementary experimental data submitted by the patentee, if a person skilled in the art can be reasonably assured of the patent applicant's assertions in the original application documents, the original patent application documents expressly record or implicitly disclose the facts to be proved that the supplementary experimental data are intended to directly prove, and the applicant is not using the supplementary experimental data to overcome inherent defects of the original patent application documents, the supplementary experimental data may be accepted as evidence proving the inventiveness of the patent.

In this case, in response to the ground for invalidation raised by the pharmaceutical company that the Patent in Suit lacked inventiveness, the Danish company subsequently submitted experimental data on technical effects during the invalidation proceedings. The supplementary experimental data can serve as evidence for assessing the inventiveness of the Patent in Suit as follows. The specific analysis is as follows:

First, according to the contents recorded in the description of the Patent in Suit, it can already be determined that the original application documents recorded the technical effect that 21 compounds, including Si*tide, have a prolonged duration of action compared with the GLP-1 compounds in the prior art. A person skilled in the art could verify this technical effect by conventional methods. The description of the Patent in Suit further provides the basis on which a person skilled in the art can be reasonably assured that the 21 compounds, including Si*tide, can prolong the duration of action compared with the GLP-1 compounds in the prior art. It can be seen that the description of the Patent in Suit does not merely broadly record the technical effects of compounds of a general formula, but records relevant contents that enable a person skilled in the art to be reasonably assured that the specific technical effects of the specific compounds are superior to the prior art. In such circumstances, it cannot be held, merely because the description does not separately record result data on the technical effects of the 21 specific compounds, that the 21 specific compounds, including Si*tide, are a selection invention made after the filing date, thereby depriving the patentee of the opportunity to prove in the invalidation proceedings, through evidence in the form of supplementary experimental data, that the Patent in Suit is inventive.

Second, from the perspective of the verification process and method, the description of the Patent in Suit uses the potency and duration of action measured in the db/db mouse experiments and the pharmacokinetic data measured in the intravenous and subcutaneous injection experiments in minipigs as the basis for screening GLP-1 compounds with a longer duration of action, which is consistent with the verification method of the supplementary experimental data submitted by the Danish company.

In summary, the challenged decision improperly refused to accept the experimental data supplementarily submitted by the Danish company and improperly determined the technical effects and the technical problem actually solved by the invention; therefore, the court ordered CNIPA in accordance with the law to make a new examination decision.

Gist of the Judgment

In patent invalidation proceedings, where the patentee submits supplementary experimental data after the filing date to prove the technical effects of the patent, the data must be consistent with the technical effects already recorded in the original description; entirely new effects not mentioned in the original application cannot be added afterwards. As to supplementary experimental data submitted by the patentee, if a person skilled in the art can be reasonably assured of the patent applicant's assertions in the original application documents, the original patent application documents expressly record or implicitly disclose the facts to be proved that the supplementary experimental data are intended to directly prove, and the applicant is not using the supplementary experimental data to overcome inherent defects of the original patent application documents, the supplementary experimental data may be accepted as evidence proving the inventiveness of the patent.

Related Index

Article 22, paragraph 3 of the Patent Law of the People's Republic of China (as amended in 2020) (Article 22, paragraph 3 of the Patent Law of the People's Republic of China as amended in 2000 applies to this case)

First instance: Administrative Judgment (2023) Jing 73 Xing Chu No. 1324 of the Beijing Intellectual Property Court (November 6, 2023)

Second instance: Administrative Judgment (2023) Zui Gao Fa Zhi Xing Zhong No. 1282 of the Supreme People's Court (December 26, 2025)

Attachment: Gist of the case (PDF, Chinese original)

Source：Intellectual Property Court of the Supreme People's Court News；2026-10-20；https://ipc.court.gov.cn/zh-cn/news/view-6181.html