As in many other jurisdictions, China does not allow computer programs as such to be patented, but does not rule out patentability for inventions related to computer programs.
A number of exceptions to patentability are set out by Article 25(2) of the Chinese Patent Law, one of which relates to rules and methods for performing mental activities. This is the exception that is often cited by Chinese examiners to raise non-patentable subject matter objections against inventions related to computer programs.
Claims essentially relating to one of the following, even if presented in the form of a solution to a problem, are normally regarded by Chinese examiners as defining rules and methods for performing mental activities:
methods of calculation or rules of mathematical calculation;
computer programs as such or computer programs recorded on computer-readable media; and
rules and methods for playing games.
However, if a claim recites technical features apart from content relating to methods for performing mental activities, patentability cannot be ruled out for the claimed subject matter under Article 25(2) of the Chinese Patent Law.
Software patent applications may also be rejected under Article 2.2 of the Chinese Patent Law for lack of a technical solution.
A 3-step test is normally applied to decide whether an Article 2.2 objection should be raised:
whether the claimed subject matter involves execution of computer programs in order to solve a technical problem;
whether the computer programs are executed by a computer so as to control or process internal or external objects of the computer in accordance with the laws of nature;
whether any technical effect is achieved in accordance with the laws of nature by execution of the computer programs.
Failing any one of the three steps, the claimed subject matter will not be regarded as a technical solution in the sense of Article 2.2 of the Chinese Patent Law.
In order to obtain appropriate patent protection for software inventions, certain rules need to be respected when drafting applications for such inventions.
If means-plus-function language is used for a product claims, it is important to ensure strict one-to-one correspondence between recited means and steps recited in the corresponding method claim. Although the Guidelines allow means-plus-function language to be used for product claims, in practice, it is not uncommon for Chinese examiners to raise objections against means-plus-function claims on grounds of lack of support by the description.
Chinese practice still does not allow certain types of claims. For example, claims to data structures are not patentable, but such claims can be amended to methods for generating the relevant data structures which are potentially allowable. Claims to computer-readable medium storing instructions and computer program products are not allowable either. Therefore, terms such as “data structure”, “signal”, “computer-readable medium”, “computer program product” etc. should not be used as definition of inventions in claims if fast grant is desired. However, for Chinese patent applications based on earlier foreign applications (e.g., Chinese national phase entry of PCT applications, or direct Chinese filing and claiming priority from earlier foreign applications), it is advisable to keep such claims at the time of entry/filing in the event that the Chinese practice changes later. Often, amendments or new claims (e.g., in divisional applications) based on originally filed claims are more likely to be accepted by Chinese examiners than those made based on the description.
The description of a Chinese patent application also needs to be carefully crafted to support amendments to the claims. Chinese examiners are often reluctant to allow claim amendments unless there is almost verbatim support in the specification. This is particularly relevant if the patent application originates from a jurisdiction which adopts less strict policies on added matter issues than China.
Apart from describing the solution as a whole, the description needs to clearly and completely describe the design and technical features involved in the computer programs that are necessary for achieve desired technical effects. It is advisable to include in the description technical problems that the prior art fails to solve and how the invention solves such problems. Where appropriate, it is also advisable to include some description of technical effects achieved by each technical feature or group of technical features. Chinese examiners tend to be more prepared to accept that the invention is technical if they see such description. Arguments for technical effect not based on the description, even if presented with supporting evidence, often are not accepted by the Chinese examiners.
Normally at least a main flow chart or process flow diagram needs to be included in the description of a software invention. Where specific functions or branches of a computer program involve multiple steps, it is advisable to also include flow charts corresponding to the specific functions or branches. The description needs to clearly and completely describe each and every step shown in the flow charts. If particular steps are not essential, it is important that the description explicitly says so. Otherwise, the Applicant may be forced to include corresponding steps and means in the independent claims.
Where execution of computer programs involves changes to the hardware of a computer, a diagram showing the structure of the computer should be included, and the description should describe the relevant hardware components and connections therebetween in a way clear and sufficient for a skilled reader to implement the invention.
The above is only a brief discussion of the particulars that one needs to be aware of if he wishes to patent his software invention in China. For more detailed information, please contact Handong Ran at firstname.lastname@example.org.
 Computer programs are defined in the Guidelines for Patent Examination of the Chinese Patent Office (Guidelines) as “coded instruction sequences executable by an information processing device, e.g., a computer, to obtain certain results”, or “symbolized instruction sequences or symbolized statement sequences that can be automatically transformed into coded instruction sequences”; a software invention is defined as “a solution to an identified problem, which is wholly or partly based on processes of computer programs, for controlling or processing external or internal objects of a computer via execution of the computer programs by a computer”.
 Computer games that involve performance improvements for the computer running the games or technical changes to the structure or function of the computer running the games may potentially be patentable.
 A “technical solution” is defined in the Guidelines as “aggregation of technical means applying the laws of nature to solve a technical problem”.