Except for the types of contracts whose entry requirement is filing and registration as stipulated by laws and regulations, general contracts (including trademark use contracts) will take effect after both parties sign and seal them, provided that both parties agree on their intentions and the form and content are not illegal. However, according to the laws of our country, if the trademark license contract is not filed in the Trademark Office, it shall not be opposed to a bona fide third party, that is to say, the licensing parties shall not oppose the bona fide third party to claim the validity of the trademark license without filing, provided that the third party should be bona fide. A trademark license contract is legal and valid as long as both parties reach an agreement without filing.
Reference Law: Interpretation of the Supreme People's Court on Several Issues Concerning the Application of Law in the Trial of Trademark Civil Disputes Article 19 If a trademark license contract is not filed, it will not affect the validity of the license contract, unless otherwise agreed by the parties. If the trademark license contract is not filed with the Trademark Office, it shall not be opposed to a bona fide third party.