Article 20

A trade mark shall be liable to revocation if, after the date on which it was registered:
(a) as a result of acts or inactivity of the proprietor, it has become the common name in the trade for a product or service in respect of which it is registered;
(b) as a result of the use made of it by the proprietor of the trade mark or with the proprietor's consent in respect of the goods or services for which it is registered, it is liable to mislead the public, particularly as to the nature, quality or geographical origin of those goods or services.