X0306 4/A 2013-02-28 2013-03-04 0 0001262823 WESTLAKE CHEMICAL CORP WLK 0001551480 Teel Lawrence E. 2901 POST OAK BLVD. HOUSTON TX 77056 0 1 0 0 Vice President, Olefins Common Stock 2013-02-28 4 F 0 2 84.7 D 1419 D Common Stock 2013-02-28 4 F 0 194 84.09 D 1225 D The number of shares of common stock held by the reporting person was incorrectly reported on the first transaction shown on the reporting person's original Form 4 filed February 28, 2013 (and correspondingly on the subsequent transaction shown on such Form 4). Lawrence E. Teel by Richard C. Kroger PoA 2013-03-14