(1) The assertion of claims in accordance with section 8 (1) is not permissible if, giving due consideration to all the facts and circumstances, they are abusive.
(2) In case of doubt, an abusive claim is to be assumed where
1. asserting the claims predominantly serves to establish a claim to compensation of expenses or of legal expenses or payment of a contractual penalty against the infringer,
2. a competitor is asserting a considerable number of infringements of the same legal provision by issuing written warning notices if the number of asserted infringements is disproportionate to the extent of the competitor’s own business activity or if it is to be assumed that the competitor does not itself bear the economic risk of its extrajudicial or court action,
3. a competitor sets the value of a written warning notice inappropriately high,
4. manifestly excessive contractual penalties have been set or demanded,
5. a proposed obligation to cease and desist manifestly goes beyond the infringement which has incurred the written warning notice,
6. several infringements which could have incurred a joint written warning notice each incur a separate written warning notice, or
7. on account of an infringement for which several infringers are responsible the claims against the infringers cannot be jointly asserted without material reason.
(3) In the case of abusive claims, the opponent may demand from the claimant compensation for any expenses necessary for its legal defence. Further claims for compensation remain unaffected.