If a contract is made in such a manner that, at the time when the contract is concluded, only the class of insured interest is designated, and it is only specified to the insurer in detail once the contract has been concluded (open policy), the policyholder is obliged either to give notice of the individual insured risks without undue delay or, if the insurer has waived that right, of the agreed basis on which the insurance premium is to be calculated or, if this has been agreed, to apply for a cover note in each respective case.