Break the law. Forging someone else's signature constitutes fraud. If it is used to make perjury, it constitutes perjury. If it is used to forge government documents, the circumstances are even more serious. Signature has legal effect, and forged signature bears legal responsibility. However, just forging a signature does not constitute a criminal offence, and it is necessary to comprehensively judge whether it constitutes a crime and what kind of crime it constitutes by combining the specific behavior, social harm and harmful consequences after forgery.

According to the authorization of the transferor, it is legal to sign on behalf of the transferor, and it is illegal to sign on behalf of others without the authorization of the principal.

1. Signing on behalf of the authorized person is a legal act. This phenomenon is very common in real life. Some are trivial matters of life, others are important economic activities and important matters, and the client authorizes others to sign them. For example, it is normal for customers to give their ID cards and power of attorney to customers to pick up express mail or even sign contracts.

It is illegal to sign on behalf of others without the entrustment or authorization of the client. Seriously, you should bear criminal responsibility. For example, if a national civil servant signs an important request without the consent, approval or authorization of the person who has the right to deal with it, causing heavy economic losses or casualties, he will bear criminal responsibility.

Legal basis:

People's Republic of China (PRC) Civil Code

Article 171 Where an actor has no agency, exceeds the agency or remains an agent after the agency is terminated, it shall not be effective to the principal without ratification by the principal.

The counterpart may urge the principal to ratify it within 30 days from the date of receiving the notice. If the trustor fails to declare it, it shall be deemed as refusal to ratify it. Before the act committed by the actor is ratified, the bona fide counterpart has the right to revoke it. Revocation shall be made by notice.

If the act committed by the actor is not ratified, the bona fide counterpart has the right to demand the actor to perform the debt or demand the actor to compensate for the damage he has suffered. However, the scope of compensation shall not exceed the benefits that the counterpart can obtain when the principal ratifies.

If the counterpart knows or should know that the actor has no right to act as an agent, the counterpart and the actor shall bear the responsibility according to their respective faults.