Determining ‘same subject matter’ for Chinese patent priority

The principle of priority is one of the important principles in China’s patent regime. Pursuant to article 29 of the Patent Law, if, within 12 months from the date of first filing a patent application for an invention or utility model in China or a qualified foreign country, an applicant further files a patent application with China’s Patent Office in respect of the same subject matter, the applicant will enjoy domestic or foreign priority.

From the above it can be seen that “same subject matter” is a major condition for priority, whether for domestic or foreign priority. If the subject matter of the subsequent filing is different from that of the previous filing, the applicant is not eligible for priority. Accordingly, determining whether the subject matter of two filings is the same is an important issue.

Judgment principles

The Patent Examination Guidelines provide as follows in respect of determining whether the subject matter of a subsequent filing is the same as that of a previous filing: determine whether the technical solutions described in the claims of the subsequent application are clearly recorded in the documents for the previous filing.