X0306 4 2018-02-27 0 0001604665 Westlake Chemical Partners LP WLKP 0001330417 Bender Mark Steven 2801 POST OAK BOULEVARD, SUITE 600 HOUSTON TX 77056 1 1 0 0 SVP, CFO and Treasurer Common Units (Limited Partner Interests) 2018-02-27 4 P 0 2000 23.7675 A 12000 D The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions ranging from $23.725 to $23.795, inclusive. The reporting person undertakes to provide to Westlake Chemical Partners LP, any security holder of Westlake Chemical Partners LP 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. M. Steven Bender by J. Feng POA 2018-02-27