Atlas Energy, L.P. and its midstream oil and gas subsidiary, Atlas Pipeline Partners, L.P. , have announced the completion of the merger transactions of Atlas Energy with a subsidiary of Targa Resources Corp. and Atlas Pipeline with a subsidiary of Targa Resources Partners LP . The consummation of the mergers follows the approval of the merger by ATLS and APL unitholders as well as TRC stockholders at special meetings which occurred on Friday, February 20, 2015.