1. Without prejudice to any information requested pursuant to Article 20 and information and reporting obligations under national law other than the general authorisation, national regulatory and other competent authorities may require undertakings to provide information with regard to the general authorisation, the rights of use or the specific obligations referred to in Article 13(2), which is proportionate and objectively justified in particular for the purposes of:

(a) verifying, on a systematic or case-by-case basis, compliance with condition 1 of Part A, conditions 2 and 6 of Part D, and conditions 2 and 7 of Part E, of Annex I and of compliance with obligations as referred to in Article 13(2);

(b) verifying, on a case-by-case basis, compliance with conditions as set out in Annex I where a complaint has been received or where the competent authority has other reasons to believe that a condition is not complied with or in the case of an investigation by the competent authority on its own initiative;

(c) carrying out procedures for and the assessment of requests for granting rights of use;