Southwestern Energy Co. saw the largest drop in short interest relative to shares outstanding among SNL-covered midstream and related companies in the second half of November but stayed on top of the list for overall short interest.

The percentage of the company's shares held short relative to shares outstanding declined 113 basis points, to 10.67%, from Nov. 15 to Nov. 30.

Sunoco Logistics Partners LP saw the biggest rise in short interest relative to shares outstanding among the group. The percentage of the company's shares held short relative to shares outstanding climbed 81 basis points, to 1.23%, as of Nov. 30.