Change of patent agent: the patent agency can handle it.
Change of inventor: a certificate signed by all inventors is required. Proof content: if the number of people decreases, it proves that the reduced person did not participate in the invention and creation, and was not an inventor; If it is to increase the number of people, it proves that the increased people participated in the process of invention and creation and paid creative labor for invention and creation.
The change of the applicant: it belongs to the transfer of the patent application right, that is, he was once one of the obligees. Now he wants to transfer his rights to others, and he needs to produce materials signed by the transferor and the transferee to prove his right to transfer.