UPDATE 1-Energy Transfer to drop down Southern Union interest
* Unit to also hold assets acquired in ETP's $5.35 bln Sunoco deal
* Drop down to occur when Sunoco deal closes
June 18 (Reuters) - Pipeline operator Energy Transfer Equity will drop down its interest in Southern Union Co into a new unit, which will be controlled by related company Energy Transfer Partners LP.
The unit, which will be called ETP Holdco Corp, will also include assets acquired in Energy Transfer Partners LP 's $5.35 billion buy of Sunoco Inc in April.
The pipeline industry has seen a flurry of activity spurred by development of shale oil and gas fields and master limited partnership (MLP) structures that have provided the industry with rich tax breaks.
In the MLP structure, general partners drop down or transfer suitable assets into the MLP from time to time.
Energy Transfer Equity will hold a 60 percent interest in the new entity while Energy Transfer Partners will own the remaining 40 percent.
"This new entity will increase Energy Transfer Partners' scale of operations and its ability to serve more customers in the rapidly expanding midstream marketplace," Energy Transfer Equity Chairman Kelcy Warren said in a statement.
The drop down is expected to occur when Energy Transfer Partners' deal with Sunoco closes.
The companies said interests in Sunoco Logistics Partners LP will be transferred to Energy Transfer Partners, prior to the drop down.
Energy Transfer Equity, which is the owner of the general partner of Energy Transfer Partners, bought rival Southern Union Co for $5.5 billion after it won a bidding war with Williams Cos Inc.