First, when both parties apply for a marriage certificate, their signatures are not signed by themselves, and they are not formal couples, which is legally invalid. The reason for this is the following：

1. Article 5 of the Marriage Law of the People's Republic of China * * * Marriage must be entirely voluntary, and neither party may force the other party or any third party to interfere in signing.

2. Article 8 of the Marriage Law of the People's Republic of China requires both men and women who are married to register their marriage in person at the marriage registration office. Those who meet the requirements of this law shall be registered and issued a marriage certificate. Getting a marriage certificate is tantamount to establishing a relationship between husband and wife. Those who have not registered for marriage shall re-register.

If both parties don't sign the marriage certificate themselves, it doesn't mean that I am willing to get married. Therefore, the marriage relationship is invalid. Marriage registration shall be attended by both husband and wife in person. If marriage registration is fraudulently obtained, the marriage registration authority may cancel the registration.