Article 31 of the Patent Law stipulates that an application for a patent for an invention or utility model shall be limited to one invention or utility model. Two or more inventions or utility models belonging to a general inventive concept may be filed as one application. Where an application for a patent includes more than two inventions, the applicant may file a divisional application on his own initiative or according to the examination opinions of the examiner. The difference between divisional application and ordinary patent application is that divisional application enjoys the filing date of the original application, and the filing date of divisional application is only the filing date of divisional application; All statutory time limits for divisional applications are calculated according to the filing date of the original application; The divisional application has its prescribed submission time. Once the applicant misses the filing time stipulated by the Patent Office, the applicant or the patentee cannot submit the divisional application again. Despite the above differences between the divisional application and the ordinary application, the divisional application is the same as the ordinary application in terms of patent fees and examination procedures.