page 10  Section 2: Unity of the invention, and modification and division of the application Article 28: The application shall be limited to a single main subject matter with the detailed objects that compose it and the applications indicated. It may not contain restrictions, conditions or reservations. It shall indicate a title designating the subject matter of the invention in a concise and accurate manner. Article 29: The applicant may modify the application up until the time it is noted that the application meets the necessary conditions for the grant of the patent. However, the modification may not go beyond the subject matter set out in the initial application. Article 30: The applicant may divide the application into several applications known as divisional applications up until the time it is noted that the application meets the necessary conditions for the grant of the patent. However, no divisional application may go beyond the subject matter set out in the initial application. Each divisional application shall bear the date of filing and, as the case may be, the date of priority of the initial application. Section 3: Priority claims Article 31: Anyone wishing to claim the priority of a prior filing must attach the following to his patent application, at the latest within 12 months following the filing of his application, and send to the Industrial Property Director: 1. a written statement indicating the date and number of this prior filing, the country in which it was made and the name of the applicant; 2. a certified true copy of said prior application; 3. written authorization from the applicant or his successors in title empowering him to claim the priority in question if he is not the author of this application. Article 32: An applicant wishing to claim several rights of priority for an application must, for each of them, comply with the same requirements set out in Article 31. He must further pay a fee by right of priority claimed and produce proof of payment of said fee within the same period of 12 months provided for in that same Article. Article 33: Failure to furnish any of the above-mentioned items in due time shall automatically lead, for the sole application considered, to the loss of benefit of the claimed right of priority. Any item which reaches the Industrial Property Director later than 12 months after the filing of the application for registration shall be deemed inadmissible. Article 34: The filing in Burundi of this application for the claiming of priority before the expiration of the set time limit of 12 months may not be invalidated by any act