WESTLAKE CORP — Director's Dealing 2017

Feb 28, 2017

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: WESTLAKE CHEMICAL CORP (WLK)
CIK: 0001262823
Period of Report: 2017-02-23

Reporting Person: Chao Albert (Director, President & CEO, 10% Owner)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2017-02-23	Common Stock	M	42180	$15.805	Acquired	316198	Direct
2017-02-23	Common Stock	S	42180	$63.3505	Disposed	274018	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2017-02-23	Employee Option (right to buy)	$15.805	M	42180	Disposed	2017-02-23	Common Stock (42180)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	92010554	Indirect

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 February 23, 2017 for ease of reporting. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions ranging from $63.28 to 63.49, 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: The stock options are exercisable in three equal installments on February 23, 2008, 2009 and 2010.

F3: 92,010,554 shares of Issuer are held through TTWF LP, a Delaware limited partnership. Two trusts for the benefit of members of the Chao family, including the reporting person, are the managers of TTWFGP LLC, a Delaware limited liability company that is the general partner of TTWF LP. The limited partners of TTWF LP are five trusts, principally for the benefit of members of the Chao family, including the reporting person, and two corporations owned, indirectly or directly, by certain of these trusts and by other entities owned by members of the Chao family, including the reporting person. The reporting person shares investment and voting power with respect to the shares beneficially owned by TTWF LP. The reporting person disclaims beneficial ownership of the shares except to the extent of her pecuniary interest therein.