It is OK to cover two seals on the perforation. In fact, one party can seal it. However, in order to show that both sides are equal, you can cover them twice. The seal on the perforation is a rigorous operating procedure, that is, by affixing the seal on the perforation, it means that all pages of the contract have certain traces, and it is not easy to add the number of pages at random, which will change the contents of the contract and increase the trouble of identifying the authenticity of the contract for the contracting parties. The law does not require that the contract must be sealed with a seal on the perforation, which means that the contract is also valid without a seal on the perforation, but the role of the seal on the perforation is to prevent risks.
 Legal basis
 Article 502 of the Civil Code of the People's Republic of China [Effective time of the contract] A legally formed contract shall become effective from the time of its formation, unless otherwise provided by law or agreed by the parties.
 Where, in accordance with the provisions of laws and administrative regulations, a contract shall go through the formalities of approval, etc., such provisions shall apply. Failure to go through approval and other procedures that affect the effectiveness of the contract shall not affect the effectiveness of the obligation clauses in the contract such as performance of approval and relevant clauses. If the party who should go through the formalities of application for approval fails to perform its obligations, the other party may request it to bear the responsibility for breach of such obligations.
 In accordance with the provisions of laws and administrative regulations, the provisions of the preceding paragraph shall apply to the modification, transfer, dissolution and other circumstances of a contract where approval and other formalities shall be handled.