; (II) the multiple start dates share a common end date; (III) no more than 120 days separate the first start date and the final start date listed in the petition; and (IV) the need for multiple start dates arises from variations in labor needs associated with the job opportunity identified in the petition. (ii) Labor contractors A labor contractor may not file a petition described in clause (i) unless the labor contractor— (I) is filing as a joint employer with its contractees, or is operating in a State in which joint employment and liability between the labor contractor and its contractees is otherwise established