Article 30 of the Patent Law stipulates that an applicant who claims priority shall make a written statement at the time of application and submit a copy of the first patent application document within 3 months; Failing to submit a written statement or a copy of the patent application documents within the time limit shall be deemed as not claiming priority. So option a is wrong. Section 6.2.10, Chapter 1, Part I of Patent Examination Guide 20 10 stipulates that the applicant claiming priority in the latter application shall be the same as the applicant recorded in the copy of the earlier application document, or the same as one of the applicants recorded in the copy of the earlier application document. If the applicants are completely inconsistent, if the applicant of the earlier application transfers the priority to the applicant of the later application, it shall submit the certificate of priority transfer signed or sealed by all the applicants of the earlier application within 3 months from the date of filing the later application. So option b is correct. Section 6.2.2. 1 0, Chapter 1, Part I of the Patent Examination Guide stipulates that the earlier application and the later application claiming priority shall meet the following requirements: …… (3) The subject of the earlier application has not been granted a patent right. Although the applicant avoids repeated authorization by giving up the patent right of the earlier application that has been authorized when claiming priority, the abandonment of the patent right is not regarded as abandonment from the beginning, but is terminated from the date of issuing the notice of waiver procedures. This will lead to the patent protection period of the invention from the date of the first application to the expiration date of the next application 10 year (utility model) or noon on the 20th (invention), resulting in unreasonable extension of the patent protection period. Therefore, even if the applicant gives up the patent right of the earlier application that has been authorized, he cannot enjoy the priority, so the statement of option C is wrong. Section 6.2.3 of Chapter 1, Part I of Patent Examination Guide 20 10 stipulates that if an applicant requests to withdraw his priority claim, he shall submit a declaration of withdrawal priority signed or sealed by all the applicants. Section 4.10, Chapter 1, Part I of Patent Examination Guide 20 10 stipulates that the representative can handle other formalities in the patent office on behalf of all applicants, except those directly related to the rights of * * *. Procedures directly related to * * * rights include: filing a patent application, entrusting a patent agent, transferring the right of patent application, priority or patent right, withdrawing the patent application, withdrawing the priority claim, and giving up the patent right. Procedures directly related to the rights of * * * shall be signed or sealed by all rights holders, and shall not be handled by representatives. So option d is wrong. To sum up, the answer to this question is: a, c and d.