Section 5. Each person, before engaging in business as a milk dealer, shall make application to the commissioner for a license hereunder, which the commissioner is hereby authorized to grant. Such application shall state the nature of the business to be conducted, the name and principal business address in the commonwealth of the applicant, and, if a firm or association, the name and address of each member thereof, or if a corporation, the names and addresses of all officers and directors thereof, and the name of each municipality in which business is to be conducted, and such other facts with respect to the business of the applicant as may be required by the commissioner. Licenses issued hereunder shall expire twelve months from the effective date of said license. Any licensee whose application for renewal is made on or before the fifteenth day prior to the expiration date may continue to engage in the milk business pending the action of the commissioner on such application. Every application for a license made by a person other than a licensee shall be acted upon by the commissioner within thirty days after his receipt thereof. Every license issued under any provision of this chapter shall state that it is subject to this chapter and the original license or a certified copy thereof shall be conspicuously displayed by the licensee in each place of business conducted by him in this commonwealth.