Section 174J. The broker, at the time or before an application is taken for the policy, shall deliver a separate written notice to the prospective insured disclosing the relationship between the broker and the controlled insurer; except that if the business is placed through a subbroker who is not a controlling broker, the controlling broker shall retain in his records a signed statement from the subbroker that the subbroker is aware of the relationship between the insurer and the broker and that the subbroker has notified the prospective insured of the relationship by separate written notice at or before the time application was taken.