(1) An aggravation of the risk insured is only deemed to be such change in the risk factors regarded as constituting an aggravation of the risk insured by explicit agreement; the agreement must be made in writing.
(2) An insurer may no longer assert an aggravation of the risk insured once five years have elapsed since the increase. If the policyholder has intentionally or fraudulently breached his or her obligation under section 23, this time limit is ten years.
(3) Section 41 applies with the proviso that a reduction of the premium may only be demanded on account of such a reduction of risk factors deemed to be so by explicit agreement.