WESTLAKE CORP — Director's Dealing 2015

May 8, 2015

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: WESTLAKE CHEMICAL CORP (WLK)
CIK: 0001262823
Period of Report: 2015-05-08

Reporting Person: Kenner Andrew (VP - Manufacturing)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2015-05-06	Common Stock	M	6092	$30.0525	Acquired	18273	Direct
2015-05-06	Common Stock	M	2526	$22.915	Acquired	20799	Direct
2015-05-06	Common Stock	S	8618	$72.269	Disposed	12181	Direct
2015-05-06	Common Stock	S	2161	$72.3169	Disposed	10020	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2015-05-06	Employee Option (right to buy)	$30.0525	M	6092	Disposed	2022-02-17	Common Stock (6092)	Direct
2015-05-06	Employee Option (right to buy)	$22.915	M	2526	Disposed	2021-02-18	Common Stock (2526)	Direct

Footnotes

F1: In accordance with the Securities and Exchange Commission's No Action Letter dated June 25, 2008, we have aggregated the sales that occurred on May 6, 2015 for ease of reporting. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions ranging from $72.25 to $72.34, 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.

F2: In accordance with the Securities and Exchange Commission's No Action Letter dated June 25, 2008, we have aggregated the sales that occurred on May 6, 2015 for ease of reporting. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions ranging from $72.31 to $72.34, 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.

F3: The stock options are exercisable in three installments of 33%, 33% and 34% on February 17, 2013, 2014 and 2015, respectively.

F4: The stock options are exercisable in three installments of 33%, 33% and 34% on February 18, 2012, 2013 and 2014, respectively.