Legal analysis: citizens and legal persons can carry out civil legal acts through agents. An agent carries out civil legal acts in the name of the principal within the scope of agency authority. The principal shall bear civil liability for the agent's agency behavior. In other words, a civil appeal must be implemented by an agent in the name of the principal. Without the official seal of the appeal company, only the signature of the entrusted agent is valid.

Legal basis: Civil Code of People's Republic of China (PRC).

Article 161 A civil subject may carry out a civil juristic act through an agent. In accordance with the provisions of the law, the agreement of the parties or the nature of civil legal acts, civil legal acts that should be implemented by themselves shall not be represented.

Article 162 A civil juristic act carried out by an agent in the name of the principal within the scope of his agency authority is effective for the principal.