An increasing number of foreign enterprises and individuals have filed Chinese patent applications in recent years. However, as the patent laws and regulations of China contain provisions not found in other jurisdictions, it is necessary to adopt an effective strategy when drafting a patent application that aligns with domestic patent practice so as to obtain effective patent protection in China.

Use different degrees of generalization and technical perspectives to describe key technical content. The Patent Law and Examination Guidelines have strict provisions in respect of amendment. Namely, amendments to patent application documents should be documented in the original description and claims, or be capable of being directly and unambiguously determined from the original description and claims.

More specifically, if the original application documents only describe specific technical content, further summation or generalization of the technical content will normally not be permitted once the application has been filed. If the broad scope sought in the original claims is challenged by prior arts, the applicant will have to limit their claims in line with the specific technical content in the original description, resulting in an unduly narrow scope of protection.

Accordingly, it is necessary for the applicant to use different degrees of generalization and technical perspectives in describing the key technical content in the patent application description. For example, if the specific technical content is the formula G=R2+R and R>1, a number of intermediate generalizations can be added in the original description based on the function of the formula in the technical solution, e.g. G increases as R increases; when R increases by a specific quantity, G will increase by a quantity greater than the specific quantity; when R=0, G=0 and the like.

Using different degrees of generalization and technical perspectives to describe key technical features makes it much easier to amend the claims as desired after the application has been submitted so as to avoid having to unduly narrowly narrow down the claims in order to get the patent allowed.

Place important technical features in dependent claims. The examination guidelines stipulate that the specific methods of revising claims once a patent has been granted are generally limited to the deletion and combination of claims and the deletion of technical solutions. Furthermore, in general, technical features not included in granted claims may not be added to claims.

Here it can be seen that once a patent has been granted, a patent holder may not use content in the description to overcome deficiencies, even where the description contains technical content that can overcome deficiencies in the claims. Accordingly, dependent claims may be the only means of remedying a fatal deficiency in an independent claim.

Given these strict limitations on revision once a patent has been granted, important technical content should be included in the dependent claims when drafting the patent application to the greatest extent possible, so that the dependent claims can serve as a sturdy bulwark that makes up for the deficiencies in the independent claims. Dependent claims should address not only challenges posed by prior art, but also possible deficiencies, e.g. a lack of clarity in the independent claims or lack of support for a technical solution from the description, so as to sufficiently fulfil their protective role.

Do not unbendingly pursue the broadest scope of protection. The doctrine of equivalents may be applied in domestic patent infringement actions, while the doctrine of estoppel can constitute a limitation on application of the doctrine of equivalents.

Accordingly, if a claim is granted after amendment and statement of limiting opinions, it is likely to be subject to the doctrine of estoppel in a patent infringement action. If a similar claim has not been subject to substantial amendment or a statement of limiting opinions, it may better be able to enjoy the application of the doctrine of equivalents. Accordingly the unbending pursuit of the broadest scope when drafting a patent application may produce the opposite result, while drafting claims with the appropriate scope of protection may, contrarily, be more beneficial in an infringement action.

A stable right is a key condition to securing effective patent protection. Due to strict limitations on revision once a patent has been granted as mentioned above, carrying out sound revision when responding to an Office Action is conducive to securing a stable right. Putting one’s hopes on remedies that may be available after the granting of a patent, meanwhile, could expose one to numerous significant risks.

Draft several types of independent claims for a computer-related patent application involving computers. Although there has been a large number of computer-related patents granted in China, patent infringement cases have not clearly indicated what kinds of claims can effectively protect computer-related inventions or how the scope of protection of such claims is to be interpreted. To the contrary, these cases serve more to demonstrate that the requirements in respect to the drafting of patent documents are inconsistent between the courts and the patent office.

To most effectively respond to the uncertainty existing in patent infringement judicial procedure, we would recommend that several types of claims be included in applications for computer-related patents. These could include process claims, apparatus claims comprising functional modules and apparatus claims comprising specific hardware + processor/ controller. A detailed description of the hardware environment should also be provided in the description.

Chinese patent laws and regulations may contain provisions not found in those of other countries, but fully understanding and addressing these provisions in drafting patent applications as described above is conducive to securing more effective patent protection in China.