How do US and Chinese disclosure practices compare?
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How do US and Chinese disclosure practices compare?


He Zhao and Jing Zhang of CN-KnowHow compare disclosure practices in the US and China, examining different drafting strategies available to applicants

For a period of time, when filing patent applications in China, most US applicants translated US application documents into Chinese and filed the translated documents directly, with simple formality issues amended occasionally, as application documents in China. At the time of writing the US application documents, there was almost no consideration of Chinese Patent Law and examination practice. Similarly, for applicants from other countries, Chinese translations of their domestic or US application documents were usually filed directly as application documents in China for reasons of global patent layout, practical feasibility etc.

With the development of the Chinese economy and the improvement of the patent system in China, in recent years, most international applicants have attached importance to the examination of applications in China and begun studying Chinese Patent Law and prosecution practices. Some of these applicants have taken relevant requirements in Chinese Patent Law into consideration when drafting application documents for entry into China.

Regarding applications which use translations of the text of the US application documents as filing documents in China, there is usually no objection relating to disclosure issues during examination, since China and the US effectively share the same requirements on disclosures of inventions and embodiments. However, in specific fields, such as those involving business methods, computer program products, chemistry and biochemistry, there is the possibility of examiners raising objections based on disclosure issues. Further, due to the drafting practice and disclosure strategies of US applications, the disclosure issue may also have an effect on inventiveness and amendments during examination in China, even if the examiner does not raise disclosure issues. The following sections will compare the requirements in Chinese and US patent law on disclosure and briefly describe disclosure strategies when preparing application documents for China.

Requirements on disclosure in China and the US

According to Article 26.3 of the Chinese Patent Law, "the written description shall contain a clear and comprehensive description of the invention or utility model so that a technician in the field of the relevant technology can carry it out". This corresponds to that in the U.S.C. 35 §112, i.e. "the specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same". Further, it is prescribed by U.S.C. 35 §112 that the best mode for an invention should be disclosed in the specification. There is no requirement relating to the best mode in Chinese Patent Law, but applicants in China always disclose best embodiments in drafting practice.

Although the requirements connected to disclosure are substantially the same in China and the US, several issues should be noted when drafting international applications that are to be filed in China as well.

Drafting strategies for inventions relating to computer programs

One of the issues is drafting algorithm applications. The CNIPA issued a new version of the Patent Examination Guide, which took effect on February 1 2020, wherein more detailed examination principles for examination of applications in areas such as algorithms and business methods are set forth. As China and the US, as well as three other offices, the EPO, JPO and KIPO, have published principles for examination of algorithms applications, applicants and patent attorneys of various countries are facing challenges drafting specifications with appropriate scope to meet applicants' patent strategy.

According to Section 6.3, Chapter 9, Part II of the Patent Examination Guidelines in China, for inventions with features of algorithms or which feature rules and methods for business, there are four requirements when drafting the specification: a) all the features of the algorithms, rules or methods should be disclosed in full; b) the combination of the features above and technical features and the way that the combination solves the corresponding technical problem should be specified clearly; c) the beneficial technical effects of the invention should be recorded in detail and explained as necessary; and d) improvements on objective, not subjective, user experiences can be stated in the specification as well as how the combination of technical features and features of algorithms, rules or methods bring about such objective improvement.

Requirement a) is almost the same as that in the US. When drafting specifications, algorithms solutions should not be recorded as a black-box, and the relationship between each output and each input should be disclosed entirely. For requirement b), it should be disclosed in detail how the algorithms are implemented with technical features, i.e. the hardware etc. This requirement is applied to all product inventions relating to computer programs.

Requirements c) and d) are different from the requirements of the US, and many international applicants may overlook these requirements. They are more a suggestion than a requirement since the examiner in China will not raise an insufficient disclosure issue if there are no beneficial technical effects of features of solutions recorded in the specification. However, when evaluating the inventiveness of the claimed solutions, beneficial technical effects of the solutions beyond that of the prior art will be taken into consideration seriously, as inventiveness as prescribed by the Chinese Patent Law lies in distinctive features and notable progress. When drafting applications in China, technical effects always follow the solutions in each embodiment disclosed in the specification. Since there is no such suggestion in the US, in some of the applications filed in China that come from the US, there is no disclosure in the specification for the technical effects of the additional technical features defined in dependent claims. When such additional technical features have to be combined into the independent claim to solve inventiveness issues, applicants may have to specify the technical effects of the newly added features in the observation. Although the examiner takes the explanation from the applicant into consideration, the validity of such an explanation does not have as good results as disclosure of technical effects originally recorded in the specification. That is one of the reasons that many international applicants may come across a situation where an application receives grant in the US but is granted in China with a narrower scope or even rejected due to inventiveness issues.

Case on insufficient disclosure

Let us look at a decision on rejection for example. Decision No. 201334 was issued on Jan 10 2020, rejecting patent application No. 201511017848.6 on the grounds of insufficient disclosure of the specification. The application discloses and claims an internet online voting system. The Patent Reexamination Board objected to the specification due to insufficient disclosure of the invention in the Notification of Reexamination. It stated that the specification records that the internet online voting system includes various components, such as terminal collection, access router, voting subsystem, firewall subsystem, database server, identity authentication server, first, second, third, and fourth servers, etc. as well as the connection between them and the preparation steps for each component before voting, that is, generating, sending, receiving, and saving public and private key pairs respectively. However, there is no clear and complete description of how the various components of the internet online voting system work together to achieve a complete online voting process that requires voters to enter user passwords without carrying a USB shield. Therefore, those skilled in the art will not understand how to implement the information interaction process between the various components, and when and how each component applies a public or private key to which information.

Due to space limitations, the specific content disclosed in the specification cannot be described in detail, but the main technical solution of the application lies in the security authentication method based on the internet online voting system. For the drafting of the description, the disclosed embodiments are directed relatively to the method flow, and the technical features of the product, that is, the hardware device, are not described in detail. Although the technical solution disclosed by the application may just apply the method to an existing system, and the operation of the components in the existing system may be easily conceived by those skilled in the art, the incomplete disclosure of the hardware and the interaction between components results in a non-effective combination of method features with product features. As the applicant intends to claim the product solution, such defects in the description lead to the issue of insufficient disclosure.

In response to the Notification of Reexamination, the applicant further defined the subject to be claimed as a security authentication system based on an internet online voting system, and explained that the claimed technical solution is to achieve authentication without carrying the corresponding USB shield, and the interaction of data between the first server and the second and third servers, as well as if such data should be encrypted or signed, can be set based on actual needs which are not necessary features of the claimed solution.

However, the Board did not accept the amendment and arguments from the applicant, and specifically stated that this specification failed to disclose how the certification is downloaded from the server by a voting terminal and then used to protect transaction information. Thus, the application was finally rejected.

Based on the case above, for inventions involving computer program products such as algorithms and business methods, examination practice in China on disclosure is substantially the same as that in the US. In view of requirements on sufficient disclosure as well as subsequent examination on inventiveness, the embodiments referring to product solutions in specifications should be disclosed with algorithm steps or computer program steps sufficiently combined with corresponding components in hardware. When drafting application documents, sufficient disclosure should always be given, even for the features regarded as prior art or common knowledge in the art.

This case was chosen because the application was reexamined recently, as the proposed amendment of examination guidelines was published in last November. The Reexamination Board might refer to the examination principles in the proposal when making the final rejection.

Practice issues in Chinese patent examination

One of the issues is the disclosure of drawings. According to patent drafting practice in China, all the features defined in the claims should be recorded in the description, and all the features in the drawings that are believed to contribute to the invention should also be recorded in the description correspondingly, since features disclosed in drawings only but not recorded in the description will not be deemed as supporting the claimed inventions and also cannot be added into claims after the application has been filed. However, in the US, such disclosures are more easily accepted and claimed during examination.

Another issue is the strict limitation on amendments. Since the examiners in China accept only amendments with expressions originally disclosed in the description, which may correspond to a literal approach to "new matter" issue in the US, international applicants may often come across a situation where an amendment accepted in the US receives an objection in China. Therefore, before filing an application in China, it is advisable to add any contributing disclosures that have arisen after the original application was filed into the specification of the application in China to minimise amendments issues in China.

As a result the examination principles for inventions with features of algorithms or rules and methods for business published in China, many such applications that might be objected to due to subject matter issues (A.25 of the Chinese Patent Law) and non-technical feature issues (A.2 of the Chinese Patent Law), will no longer be blocked by the two articles above, and thus it is believed that the examination on A26.3 and A26.4 will be stricter in practice. Thus for international applicants, it is advisable to take the corresponding requirement in China into consideration when drafting application documents in order to obtain stable protection for applications in China.


He Zhao

He Zhao is the head of the foreign-related mechanical and electrical department at CN-Knowhow. He has a degree in microelectronic system design from the University of Southampton. Mr Zhao has 11 years of experience in the IP field and is experienced in drafting patent application documents, particularly in the fields of telecommunications, integrated circuit, semiconductors, automatic controls and mechanical engineering. He is adept at preparing responses to office actions and handling reexamination and invalidation matters. His languages include Chinese and English. He has handled many cases for DT Mobile, PSA, Boeing and Texas Instruments.


Jing Zhang (Crystal)

Jing Zhang is the vice president of CN-Knowhow. She has 18 years of experience in the IP field, with two years as a patent examiner at the CNIPA and 16 years working in a firm. She specialises in drafting patent application documents, especially in the fields of biotechnology and landscape engineering and is proficient in preparing responses to office actions and handling reexamination and invalidation cases. She is the trainer designated by the CNIPA, and also the lead author of a number of IP-related teaching materials and industry guiding standards. Her languages include Chinese, Japanese and English.

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