The first part of Article 3 of the Trademark Law provides that when two or more trademark owners respectively register the same or similar trademark for an identical product, the registration will only be granted to the mark which is the first in actual and continuous use within the territory of the Republic of China. The trademark registration is a substantive review of the trademark. Within six months after the approved trademark is published in the Official Gazette of the Trademark Office pursuant to Article 26 of the Trademark Law, an interested trademark owner may challenge the validity of a prior registrant’s trademark by filing an opposition proceeding on the ground of prior actual and continuous use. The opposition proceeding shall be adjudicated pursuant to the opposition procedures and the provisions set forth in Article 3 of the Trademark Law.