In the accusation of intellectual property infringement, people often use prior use as a defense. In the field of copyright and patent, if it can be proved that similar works or patents exist before the other party's rights, in the field of trademark, if they can be used before the other party's trademark is registered, then the respondent or defendant will not bear the so-called tort liability. The previous use certificate has the following points:
1. Sales record of online platform
2. Publication records of magazines, newspapers and books
3. Internet publishing records
4. Exhibition records
5. Records of promotional materials