Every insurance policy shall be executed in the name of and on behalf of the insurer by its officer, attorney-in-fact, employee, or representative duly authorized by the insurer. A facsimile signature of any such executing individual may be used in lieu of an original signature, except that in all policies other than those approved for machine vending the countersignature shall be in original handwriting. No insurance contract heretofore or hereafter issued and which is otherwise valid shall be rendered invalid by reason of the apparent execution thereof on behalf of the insurer by the imprinted facsimile signature of an individual not authorized so to execute as of the date of the policy.