The signature stamp of a notary public cannot be changed. A notary refers to a practitioner who meets the statutory requirements and engages in notarization business in a notary office. The requirements for being a notary are: 1, China nationality; 2. Be over 25 years old and under 65 years old; 3, fair and decent, law-abiding, good conduct; 4. Pass the national legal professional qualification examination; 5. Internship in the notary office for more than 2 years or 3 years and internship in the notary office 1 year or more, and passed the examination. To become a notary, an application shall be made by a person who meets the requirements of a notary. On the recommendation of a notary, the local judicial administrative department shall report to the judicial administrative department of the people's government of a province, autonomous region or municipality directly under the Central Government for examination and approval, and then report to the judicial administrative department of the State Council for appointment. The judicial administrative departments of the people's governments of provinces, autonomous regions and municipalities directly under the Central Government shall issue notaries' practice certificates.

Article 20 of the Trial Regulations on Notarization Duties shall not be a notary under any of the following circumstances: (1) Having no capacity for civil conduct or having limited capacity for civil conduct; (2) Having received criminal punishment for intentional crime or duty negligence crime; (3) Being expelled from public office; (4) The practicing certificates of notaries and lawyers have been revoked.