13U.K.Apart from the grounds of revocation provided for in section 46, the registration of a collective mark may be revoked on the ground—
(a)that the manner in which the mark has been used by the proprietor has caused it to become liable to mislead the public in the manner referred to in paragraph 4(1), or
(b)that the proprietor has failed to observe, or to secure the observance of, the regulations governing the use of the mark, or
(c)that an amendment of the regulations has been made so that the regulations—
(i)no longer comply with paragraph 5(2) and any further conditions imposed by rules, or
(ii)are contrary to public policy or to accepted principles of morality.