PLAINS EXPL& PRODTN CO

CUSIP: 726505100 Class: COM

OCONNOR, A Distinct Business Unit of UBS ASSET MANAGEMENT AM's Holding History (CIK: 0001132716)

Note: Option positions (PUT/CALL) are excluded.

Q1 2013
Shares 479,211 Value ($000) $22,748,000 Avg Close — Range —
Q4 2012
Shares 618,400 Value ($000) $29,028,000 Avg Close — Range —