1. There are clear regulations on the service of civil cases. Notices of court openings, court judgments, and mediation letters are all legal documents.

2. Article 77 of the "Civil Procedure Law" stipulates that the service of litigation documents must be accompanied by a service receipt. The recipient shall record the date of receipt and sign on the service receipt. Or stamp it. The date of receipt signed by the recipient on the delivery receipt shall be the date of delivery.

Article 78 stipulates: The service of litigation documents shall be delivered directly to the person to be served. If the person to be served is a citizen, he or she must hand it over to his adult family member who lives with him or her. If the person to be served is a legal person or other organization, the legal representative of the legal person or the principal person in charge of the other organization or the legal person or organization shall be responsible for the receipt. The recipient shall sign for receipt; if the recipient has a litigation agent, the document may be sent to his agent for signature; if the recipient has designated a collector to the people's court, the document shall be submitted to the recipient for signature. The date on which the adult family member living with the recipient, the person responsible for receiving the document from a legal person or other organization, the litigation agent or the recipient signs on the delivery receipt shall be the date of delivery.