(1) The proprietor of a trade mark or of a commercial designation shall not be entitled to prohibit the use of a later registered trade mark for the goods or services for which it has been registered if a request for cancellation of the later trade mark has been refused or would have to be refused
1. because the earlier trade mark or commercial designation did not yet have a reputation within the meaning of section 9 (1) no. 3, of section 14 (2) sentence 1 no. 3 or of section 15 (3) on the date relevant for the seniority of the registration of the later trade mark (section 51 (3)),
2. because the registration of the earlier trade mark could have been revoked or declared invalid and cancelled because of revocation or because of absolute grounds for refusal on the date of the publication of the registration of the later trade mark (section 51 (4)),
3. because there was no likelihood of confusion within the meaning of section 9 (1) no. 2, of section 14 (2) sentence 1 no. 2 or of section 15 (2) on the date relevant for the seniority of the registration of the later mark.
(2) In cases falling under subsection (1), the proprietor of the later registered trade mark may not prohibit the use of the earlier trade mark or commercial designation.