X0306 4 2015-02-18 0 0001262823 WESTLAKE CHEMICAL CORP WLK 0001439749 Kenner Andrew 2801 POST OAK BOULEVARD, SUITE 600 HOUSTON TX 77056 0 1 0 0 VP - Manufacturing Common Stock 2015-02-18 4 F 0 1017 66.7869 D 12181 D In accordance with the Securities and Exchange Commission's No Action Letter dated June 25, 2008, we have aggregated the sales that occurred on February 18, 2014 for ease of reporting. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions ranging from $66.17 to $66.79, inclusive. The reporting person undertakes to provide to Westlake Chemical Corp., any security holder of Westlake Chemical Corp. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote (1) to this Form 4. Amounts reflect the results of a two-for-one stock split on March 18, 2014 Andrew Kenner by J. Iglesias PoA 2015-02-20