Submission of supplementary experimental data in patent practice

Introduction

The submission of experimental data after the filing date (also known as post-filing data) in support of the patentability of inventions has long been debated in the Chinese patent community. While opinion is divided in this regard, post-filing data provided by the applicant or patentee may serve as useful evidence if an invention is challenged for substantive defects (eg, lack of inventiveness (Article 22.3 of the Patent Law), lack of claim support (Article 26.4) or lack of sufficient disclosure (Article 26.3)). In accordance with the Patent Law and the Guidelines for Examination, post-filing data purported to demonstrate the patentability of the claimed inventions shall be permitted. This update discusses the role of post-filing data in support of inventiveness and introduces relevant patent cases for detailed analysis.

Legal basis for filing supplementary data

Further to the definition of 'inventiveness' set out in Article 22.3 of the Patent Law, the Guidelines for Examination specify that if the invention produces an unexpected technical effect as compared with the prior art, the examiner may determine that the invention involves an inventive step without the need to question whether its technical solution has prominent substantive features. Therefore, technical effect is essential in an evaluation of inventiveness.

The technical effects of the claimed invention can be demonstrated by embodiments, examples or data, in which experimental data plays an important role in proving better or unexpected technical effects, especially in fields such as chemical, pharmaceuticals and biotech. If the original description fails to include comparative data in support of the technical effects as claimed, supplementary data can be filed as useful evidence against questions raised by the examiner or challenges from a third party.

Requirements for filing supplementary data

Applicants or patentees preparing for post-filing data should be aware of:

• the timing of the submission;
• the formalities; and
• the content of the data.

Timing of data submission In theory, the applicant or patentee can file experimental data, if needed, at various stages (eg, substantive examination, re-examination, invalidation or even legal proceedings). However, there are different considerations at each stage.

At the substantive examination or re-examination stage, experimental data is more likely to be accepted because:

• there are lower requirements for the formality of evidence – for example, it is not required for extraterritorial evidence to be notarised and legalised or translated by a designated translation agency; and
• there is no cross-examination of a third party.

At the invalidation or legal proceedings stage, if a third party becomes involved, things will become more complicated. Not only are the requirements for the formality of evidence stricter, but the authenticity and relevancy of the evidence may frequently be questioned. Data submitted by one party is usually objected to by the counterparty. The alleged grounds for objection can be that the data provided by an interested party (ie, any individual or organisation with a stake) is unreliable or deficient in some way (eg, experimental conditions, methods or apparatus used or comparison standards).

In that event, the unilaterally submitted data stands a lower chance of admission if no other supporting evidence has been provided. Of course, the Patent Re-examination Board (PRB) or the court may require, if necessary, that the data be verified by a neutral organisation mutually agreed by the concerned parties. However, such a procedure is undoubtedly time-consuming and costly.

In administrative litigations, the court mainly ascertains (among other things) the legitimacy of the PRB's re-examination or invalidation decision in respect of procedure and the application of the law. Therefore, if post-filing data in support of the factual issue is filed at this stage, the data runs the risk of being rejected by the court.

In its Administrative Judgment of Final Instance 3046, the Beijing Higher People's Court specifies:

For the administrative litigation case, what should be determined is the legality of the concrete administrative act. In principle, the court's judgment shall be based on the evidence on which the administrative action at issue was made, i.e., the evidence submitted during the pre-grant proceedings by the object of the administrative action.

In this litigation case, the court explicitly questioned the timing of the supplementary data presented by the patentee, but did not directly reject it. The court found that such data was inadequate to support the inventiveness of the claimed invention and thus could not be adopted in the litigation stage.

In post-grant proceedings (including administrative litigation), though the possibility of submitting new evidence cannot be excluded, it is increasingly difficult to have the evidence accepted. Therefore, in order to lower the risk of rejection, it would be advisable to file the supplementary data in support of the inventiveness at the stage of substantive examination or re-examination (ie, as long as possible before the grant of the patent).

Formality of data There are no mandatory requirements for the formality of the data in the Patent Law or the Guidelines for Examination, unless the data is:

• formed outside mainland China – in this case, at the post-grant procedure stage (eg, invalidation or administrative litigation), the data must be notarised by a notary in the foreign jurisdiction and verified by the Chinese embassy or consulate in that jurisdiction;
• presented in a foreign language – in this case, at the substantive examination or re-examination stage, it must usually be translated into Chinese, and at the invalidation or administrative litigation stage, it must be translated by a designated translation agency with an official seal affixed; or
• presented in the form of witness testimony – in this case, at the invalidation or administrative litigation stage, the witness may be required to appear in court for a cross-examination.

Content of data In most cases, for the sake of straightforwardness, post-filing data is presented in the form of comparative results toward the closest prior art cited by the examiner. The applicant or patentee is strongly advised to follow the below principles in the preparation of supplementary data:

• The comparative data should be directed to the technical effects which were described and for which the corresponding experimental data was given in the original specification to some extent – otherwise, it is unlikely to be accepted;
• The comparison should be made between the claimed invention and the closest prior art; and
• The data should correspond to the scope of the technical solutions as claimed.

These principles will be discussed further in the following two cases.

Case 1 Case 1 relates to a patent application claiming a group of compounds with formula (I) having insecticidal activities. The examiner's objection during the granting procedure focused on whether the experimental data shown by its representative compound I-1-a-2 could support the technical benefits and thus make it inventive.

In the original description of the patent, Example C showed that compound I-1-a-2 had an activity of "≥ 90" against Phaedon cochleariae at an application rate of 1,000 parts per million (ppm) after "a desired test time". Reference document 1 (D1) cited by the examiner disclosed a similar compound – I-1-a-4 – having insecticidal activity.

As regards the data in the original description, the different result of insecticidal activities between compound I-1-a-2 of the invention and I-1-a-4 of D1 could not be well reflected due to the very high application rate in the tests. In order to make clear the comparison of such activities, during prosecution, the applicant submitted supplementary data, which was generated at a lower application rate of 10 ppm as follows:

From the above table, it was clear that the data derived from the invention had demonstrated much better insecticidal activity. The panel in the re-examination procedure finally accepted the data and opined that although the supplementary data was generated at an application rate of 10 ppm as opposed to 1,000 ppm as described in the original description, the purpose of lowering its application rate was to distinguish the insecticidal activity of the invention from that of D1 without introducing any new content for comparison.

Meanwhile, as the mortality rate was tested at the same interval (seven days) and toward the same pest, the comparative data should be accepted for evaluation. The panel thus concluded that the claimed compounds were inventive over D1 and the application was granted after further examination.

Case 2 Case 2 relates to a patent application claiming a group of pharmaceutical compounds specifically illustrated as compound 14b and its pharmaceutically acceptable salts:

In order to prove the better pharmaceutical effects of the above compound as compared with the cited prior art, the applicant submitted test results of activities of compound 15b (a hydrochloride of compound 14b) as a receptor to dopamine D2S, serotonin-5HT1A and serotonin-5HT2A, respectively. Due to a change in experimental conditions, the test results of IC50 and Ki values varied from those recited in the original description. For example, the three Ki values corresponded to less than one-half, more than two-fold and less than one-twentieth of those values in the original description. In this respect, the court opined in Administrative Judgment of First Instance 2414: "As the direction of changes and amplitude of the Ki values are inconsistent with those in the original description, it would be difficult to deem such supplementary data convincible." The court did not find in the applicant's favour.

Conclusion

As the above two cases demonstrate, post-filing data collected with modified experimental conditions can be accepted for the purpose of comparison of the technical effects between the claimed invention and the prior art, provided that the modified conditions do not result in inconsistencies with the effects disclosed in the original description.

Another issue in relation to the acceptance of supplementary data focuses on the basis for submission. If there were no examples or the examples provided only a qualitative result in the original description, there might be no basis for submitting supplementary data to prove the benefits of the claimed invention. This principle is specified in the Administrative Judgment of Final Instance 2470 (2017):

If the applicant or patentee wishes to prove the inventiveness of his/its invention over the prior art by filing comparative experimental data, there is a premise that the data should be directed at the technical effects clearly described in the original specification. The so-called 'technical effects clearly described' is to be construed as the technical effects which are clear, specific, verifiable and, generally, supported by objective data, but not those general, assertive or declarative. The description should enable those skilled in the art to clearly know the advantageous technical effects. In this particular case, the description of the patent in issue only describes the technical effects as 'being not only extremely potent but also having a high selectivity for β2 adrenergic receptors'. Such technical effect is general and assertive, not specific. Under the circumstances, the supplementary data shall not be accepted, otherwise it will run counter to the system of "first-to-file" for an invention.

The Administrative Judgment of Final Instance 00309 (2015) of the Beijing Higher People's Court also specifies that:

Regarding the technical effect of the invention, the original description only describes that 'the compound of formula I is used to inhibit the undesired action of TNFα' and that 'these compounds can also be used in veterinary treatment of mammal other than human in need of tissue or inhibition of TNFα production', without giving any experimental data of activities. After reading the description, those skilled in the art can only recognize that the compounds of the patent application have a general TNFα inhibition effect, without being convinced of their activities above normal level or any other unexpected technical effect. The applicant alleges that according to counter evidence 5 [a technical document describing the relevant data], the specific inventive compound (of formula I) lenalidomide has a TNFα inhibition activity about 2000 times that of thalidomide and EM-12 and thus has unexpected technical effect. However, the indicated effect and usage are neither implied in the original specification nor directly deduced from the prior art.

Further, it is worth mentioning in relation to the acceptance of supplementary data that the specific compound in the closest prior art is generally required as the comparative object. For example, for a compound claim, the compounds used as a comparative example will be the most similar compound in the closest prior art. That said, other types of comparative examples would not be completely ruled out – but they may need quite detailed analysis or explanation to convince the examiner to accept it for evaluation of the inventiveness.

Comment

The Guidelines for Examination (amended in April 2017) relax to some extent the standard for the applicant to file supplementary data in the issue of insufficient disclosure, although the judgment for the acceptance of such data in substance still depends on the corresponding content in the original disclosure. In the recent practice of patent prosecution, the examiner has tended to focus more on the issue of inventiveness of the claimed invention than on other substantive issues (eg, claim support or sufficient disclosure), especially if the examiner intends to reject the patent application.

In a nutshell, to obtain better patent protection in China, it is highly recommended that representaive data in relation to the technical results achieved by the claimed invention (available at the time of filing) be included in the original application. In case the patentability of the claimed invention is questioned or challenged, the applicant or patentee may increase their chance of success by providing supplementary data as evidence to demonstrate advantageous technical effects. In terms of timing, it is best to file supplementary data at the substantive examination or re-examination stage (ie, as long as possible before the grant of the patent).

For further information on this topic please contact Xiaoling Duan or Jing Hou at Wanhuida Peksung by telephone (+86 10 6892 1000) or email ([email protected] or [email protected]). The Wanhuida Peksung website can be accessed at www.wanhuida.com and www.peksung.com.

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