According to the Trademark Act, any use of a trademark for the same or similar goods or services dated before the filing date of the registered trademark can be cited as defence of prior use in good faith and will not be subject to civil or criminal liability due to infringement of the registered mark. However, it is questionable whether use in foreign countries or areas outside Taiwan may also be cited as defence of prior use.

In a 2015 appeal case for trademark infringement, the IP Court held that defence of prior use in good faith should limit the use to Taiwan only, including no other use outside Taiwan. The court pointed out that the Trademark Act has jurisdiction over Taiwan only. Accordingly, any exception to the trademark rights, which is not deemed infringement, should also limit the use toTaiwan.