No sidewalk cafe permit shall be effective unless the licensee has filed with the ABC Administrator evidence of insurance insuring the licensee against liability imposed, by law arising out of the ownership, maintenance or operation of such sidewalk cafe in an amount to be established by the City ABC Administrator. The city shall be named an additional insured in the policy, providing such insurance and such policy shall further provide that it may not be canceled except upon ten (10) day’s written notice (or more) filed with the ABC Administrator.