Article L123-1 of the French Code of civil enforcement procedures
Third parties may not hinder proceedings initiated with a view to enforcing or preserving claims. They shall assist in such proceedings when legally required to do so. Any person who, without a legitimate reason, evades these obligations may be forced to comply with them, if necessary under penalty of a fine, without prejudice to damages. Under the same conditions, a third party in whose hands a seizure has been made…