The law firm of Finkelstein Thompson LLP is investigating potential claims on behalf of unitholders of Pioneer Southwest Energy Partners, L.P. (NYSE: PSE) ("Pioneer Southwest" or "the Company"), concerning the Company's proposed acquisition by Pioneer Natural Resources Co. (NYSE: PXD) ("Pioneer"). Under the terms of the merger agreement, Pioneer Southwest's public unitholders will receive 0.2325 shares of Pioneer common stock for each of their Pioneer Southwest common units. Based on Pioneer's current trading price at 11:35 AM EST, the offer is worth about $40.18 per share, which is about 0.6% lower than Pioneer Southwest's Friday closing unit price of $40.41. The total deal is worth approximately $1.46 billion.

The investigation is focused on the potential unfairness of the consideration to unitholders, the process by which Pioneer Southwest's Board of Directors considered the transaction, and potential conflicts of interest among the Company's Board members.

If you are interested in discussing your rights as a Pioneer Southwest unitholder, or have information relating to this investigation, please contact Finkelstein Thompson's Washington, DC offices at (877) 337-1050 or by email at contact@finkelsteinthompson.com.

Finkelstein Thompson LLP has spent over three decades delivering outstanding representation to institutional and individual clients in financial litigation, and has been appointed as lead or co-counsel in dozens of shareholder class actions. Indeed, the firm has served in leadership roles in cases that have recovered over $1 billion for investors and consumers.

To learn more about Finkelstein Thompson LLP, please visit our website at www.finkelsteinthompson.com. Attorney advising. Prior results do not guarantee similar outcomes.

Finkelstein Thompson LLP
Elizabeth R. Makris
877-337-1050