China: CNIPA and courts open door to post-filing supplementary data

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China: CNIPA and courts open door to post-filing supplementary data

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Li Wu of AnJie Law Firm explains how the administrative and judicial sectors are slowly embracing a more favourable stance towards the acceptance of post-filing supplementary data

China had long been criticised for adopting much stricter criteria for post-filing supplementary data in the pharmaceutical field than other major patent systems. The issue was even discussed as one of the main topics of the US-China trade talks and was listed in the US-China trade deal entered into in January 2020.



As a result of this, a great number of Patent Cooperation Treaty (PCT) applications entering into Chinese national stage have been deemed as not patentable due to the lack of experimental data, either in the prosecution stage or in the post-grant proceedings. Recently, however, there are signs indicating that the tide may be changing.

Changing views from the administration

There have been positive signs on this matter from the Chinese National Intellectual Property Administration (CNIPA). For example, the CNIPA, in the recently amended Guidelines for Patent Examination (Guidelines, which took effect on January 15 2021), made efforts to clarify the criteria of accepting post-filing supplementary data by introducing two new examples that are clearly in better conformity with the USPTO and EPO practices.



According to section 3.5.1 of the amended Guidelines, the technical effect to be proved by the post-filing supplementary data should be obtainable from the disclosure of the specification, and such supplementary data applies for assessments of both inventiveness and disclosure sufficiency.



Section 3.5.2 of the amended Guidelines adds two new examples to illustrate what this phrase “obtainable from the disclosure of the specification” really means.



According to example 1, the specification records the preparation method of compound A, the effect of the compound A in reducing blood pressure, and the experimental assay for measuring the effect of the compound A in reducing blood pressure, but does not record any experimental data thereof. Under this situation, if corresponding supplementary data demonstrating that the compound A has such a technical effect of reducing blood pressure is to be submitted, the technical effect of reducing blood pressure of compound A should be deemed as obtainable from the original disclosure and such supplementary data should be accepted for patentability evaluation.



According to the example 2, it should be acceptable to submit specific values (for example, ‘15nM’) as supplementary data if the range including the end values (for example, ‘10-100 nM’) is disclosed in the specification.



To those who have been closely following the CNIPA practices, the aforesaid section 3.5.1 is merely a restatement of the amendments made by the CNIPA to address the supplementary data issue in 2017. Yet, because CNIPA never clarified how to interpret the phrase “obtainable from the disclosure of the specification” and many examiners tended to read it as “can be obtained directly and undoubtedly from the disclosure of the specification”, the amendments of 2017 failed to introduce any substantial changes in the practices concerning the post-filing supplementary data. This time, however, it is notable that the CNIPA was committed to dispel any doubts in this regard by introducing illustrating examples.



It is also notable that the CNIPA did not stop at merely amending the guidelines, but made further efforts articulating its new position through patent invalidation proceedings. For example, in the Invalidation Decision No. 47087 issued on January 5 2021, which concerns a polymorph patent relating to the antipsychotic medicine Cariprazine, the CNIPA upheld the patent validity substantially based on the post-filing supplementary data, which was very rare in the past.

Changing views from courts

There are also positive signs that have been seen from the judiciary. Notably, when compared with the CNIPA, courts in China have appeared to be even less tolerant of post-filing supplementary data in the past. It was widely believed among the judges that accepting post-filing supplementary data may compromise the principle underlying the first-to-file system and would unfairly attribute the patentees with inventions that they did not possess at the application date.



Consequently, Chinese courts only accepted post-filing supplementary data that was proved to be generated before the application date. For instance, in the retrial judgment No. 3961 ZuiGaoFaXingShen (2018), which was issued on December 31 2019 by the Supreme People’s Court, the post-filing supplementary data submitted by the patentee Boehringer Ingelheim Pharma GmbH & CoKG was flatly rejected because “the patentee cannot prove that the supplementary experimental data it submitted during the 1st instance and 2nd instance trials were generated before the priority date.”



However, it is worth of mentioning that the Supreme People’s Court’s position on post-filing supplementary data has appeared to undergo some adjustments as well. In the recently issued binding judicial interpretation “Provisions of the Supreme People's Court on Several Issues concerning Application of Law in Trials of Administrative Cases on Patent Granting and Invalidation (I)”, which took effect on September 12 2020, after several rounds of amendments, Article 12, which was drafted to specifically address the post-filing supplementary data issue, was finally free of any forms of pre-conditions and stipulated only that: “where a drug patent applicant submits supplementary experimental data after the application date and claims that the patent application should be deemed as conforming with Article 22.3 (inventiveness) and Article 26.3 (sufficiency of disclosure) of the Patent Law by relying on such data, the data shall be reviewed by the court.” The fact that this article was finally amended to have an ‘open’ form, strongly indicated that the Supreme People’s Court did not think any more that it is appropriate to set forth a cut-off pre-condition for the supplementary data.



In view of China’s booming pharmaceutical industry, many local right holders have already expressed favourable attitudes towards post-filing supplementary data. Bound by the US-China trade deal, China is also obligated to adjust the criteria of assessing post-filing supplementary data. Together, it is reasonable to expect that judgments in favour of acceptance of post-filing supplementary data are on the way.





Li Wu

Partner, AnJie Law Firm

E: wuli@anjielaw.com

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