There is no limit on the number of people. According to the query on Hualv.com. There is no prohibition under the law. There is no limit on the number of people who can pay patent application fees. It is legal to entrust a third party to pay patent fees. You only need to pay attention to whether the payer has relevant supporting documents for paying patent fees. The payer needs to provide the applicant's power of attorney, national patent agency registration certificate or patent certificate.