X0304 4 2012-03-14 1 0000859905 SOUTHWEST OIL & GAS INCOME FUND X-A LP n/a 0000880115 CLAYTON WILLIAMS ENERGY INC /DE SIX DESTA DRIVE STE 6500 MIDLAND TX 79705 0 0 1 0 Limited Partnership Interest 2012-03-14 4 P 0 9650.75 94.49 A 0 I * On March 14, 2012, the Issuer merged into Southwest Royalties, Inc., its general partner and a wholly owned subsidiary of Clayton Williams Energy, Inc. Upon the merger all limited partnerships interest of the Issuer were converted into the right to receive cash consideration and were cancelled in accordance with the Agreement and Plan of Merger between Southwest Royalties, Inc. and the Issuer dated October 28, 2011. /s/ Mel G. Riggs, signed on behalf of Clayton Williams Energy, Inc. by Mel G. Riggs, Executive Vice President and Chief Operating Officer 2012-03-14