Legal basis: copy of the patent certificate in Chapter 9, Part V of the Patent Examination Guide (1.2.2).
If a patent has more than two patentees, the Patent Office may issue a copy of the patent certificate at the request of the same patentee. The number of patent certificates issued for the same patent right shall not exceed the total number of * * * same obligees. After the termination of the patent right, the patent office will no longer issue a copy of the patent certificate.