Under Article 95, the IP Law of Vietnam, the validity of a patent shall be terminated in the following cases:
· The patent owner fails to pay the stipulated validity maintenance fee;
· The owner declares relinquishment of the patent rights;
· The owner no longer exists and does not have a lawful heir.
Where the patent owner fails to pay the validity maintenance fee before the stipulated time-limit, the validity of such patent shall, upon the expiration of such time-limit, automatically terminate as from the first day of the first valid year for which the validity maintenance fee has not been paid.