The authentication institutions that authenticate the authenticity of official seals are usually the services provided by relevant institutions, authentication centers, notary offices and other authoritative institutions. In China, the identification of official seals can usually be carried out by the following institutions:

1. Judicial Appraisal Institute: For example, Guangdong Mingjian Document Judicial Appraisal Institute: as the registered unit of Guangdong Provincial High Court, it is also the document appraisal institution with the largest number of document appraisal cases in Guangdong Province. They provide seal identification services with rich experience and professionalism.

2. China Financial Certification Center (CFCA) is one of the important financial information security infrastructures in China. After the promulgation of "People's Republic of China (PRC) Electronic Signature Law", CFCA became the first electronic authentication service organization to obtain an electronic authentication service license.

3. Market Supervision Administration: The Market Supervision Administration has the legal authority to authenticate the official seal, especially the trademark and registration information.

In addition to the above institutions, some professional law firms, intellectual property appraisal institutions and appraisal institutes can also provide official seal appraisal services. It should be noted that authoritative, impartial and professional institutions should be selected when selecting institutions for official seal appraisal to ensure the reliability of appraisal results.