No person, association or corporation shall engage in the business of milk hauling or transport in this Commonwealth unless such person holds a milk hauler's license issued by the board. Applications for such license shall be completed and filed by the milk hauler within thirty days after this amending act takes effect, or prior to his engaging in business and annually thereafter, on or before June fifteenth, by mail or otherwise, upon such forms as may be prescribed. The license year shall commence July first and shall end June thirtieth following.

Such milk hauler's licenses may not be transferred or assigned.