Insider at

04

Insider transactions

05
0 buys (P) 2 sells (S) Net: $-3,120,774 + 78 non-open-market transactions below last 12 months, based on the transactions shown below

Price change vs current quote, split-adjusted for corporate actions since the filing — not benchmarked, not annualized, not size-weighted

78 other filings hidden
DateTickerCodeSharesPriceValue Owned afterΔ ownA/Dvs now
Aug. 11, 2026 WLK S 7,489 $79.70 $596,873 674,264 Direct -1.10% Disposed -20.5% (price as of 2026-10-06)
Aug. 11, 2026 WLK S 31,384 $80.42 $2,523,901 642,880 Direct -4.65% Disposed -21.2% (price as of 2026-10-06)
May 19, 2022 WLK S 12,016 $131.11 $1,575,418 498,843 Direct -2.35% Disposed -51.7% (price as of 2026-10-06)
May 19, 2022 WLK S 20,815 $130.20 $2,710,113 478,028 Direct -4.17% Disposed -51.3% (price as of 2026-10-06)
May 19, 2022 WLK S 5,045 $129.38 $652,722 472,983 Direct -1.06% Disposed -51.0% (price as of 2026-10-06)
Dec. 2, 2021 WLK S 1,700 $89.25 $151,725 471,026 Direct -0.36% Disposed -29.0% (price as of 2026-10-06)
Dec. 2, 2021 WLK S 1,175 $90.12 $105,891 469,851 Direct -0.25% Disposed -29.7% (price as of 2026-10-06)
Dec. 2, 2021 WLK S 7,585 $91.52 $694,179 462,266 Direct -1.61% Disposed -30.7% (price as of 2026-10-06)
Dec. 2, 2021 WLK S 20,327 $92.29 $1,875,979 441,939 Direct -4.40% Disposed -31.3% (price as of 2026-10-06)
Dec. 1, 2021 WLK S 9,656 $89.47 $863,922 463,070 Direct -2.04% Disposed -29.1% (price as of 2026-10-06)
Dec. 1, 2021 WLK S 3,000 $90.47 $271,410 460,070 Direct -0.65% Disposed -29.9% (price as of 2026-10-06)
Dec. 1, 2021 WLK S 5,842 $91.83 $536,471 454,228 Direct -1.27% Disposed -31.0% (price as of 2026-10-06)
Dec. 1, 2021 WLK S 4,200 $92.78 $389,676 450,028 Direct -0.92% Disposed -31.7% (price as of 2026-10-06)
Dec. 1, 2021 WLK S 4,300 $93.98 $404,114 445,728 Direct -0.96% Disposed -32.5% (price as of 2026-10-06)
Dec. 1, 2021 WLK S 3,789 $94.80 $359,197 441,939 Direct -0.85% Disposed -33.1% (price as of 2026-10-06)
Aug. 11, 2021 WLK P 3,000 $86.21 $258,630 441,939 Direct +0.68% Acquired -26.5% (price as of 2026-10-06)
Nov. 6, 2020 WLK S 28,638 $72.08 $2,064,227 454,166 Direct -5.93% Disposed -12.1% (price as of 2026-10-06)
Nov. 6, 2020 WLK S 11,978 $73.30 $877,987 442,188 Direct -2.64% Disposed -13.5% (price as of 2026-10-06)
Nov. 6, 2020 WLK S 10,334 $74.29 $767,713 431,854 Direct -2.34% Disposed -14.7% (price as of 2026-10-06)
Nov. 6, 2020 WLK S 4,198 $75.12 $315,354 427,656 Direct -0.97% Disposed -15.6% (price as of 2026-10-06)
March 24, 2020 WLKP P 3,200 $13.46 $43,072 164,856 Direct +1.98% Acquired 60.4% (price as of 2026-10-06)
March 24, 2020 WLKP P 1,579 $14.18 $22,390 166,435 Direct +0.96% Acquired 52.3% (price as of 2026-10-06)

Showing latest 100 of 366 transactions

P = Open-market purchase · S = Sale · A = Grant/award · M = Option exercise · G = Gift · F = Tax withholding

Insider transactions are not a recommendation; sales are often driven by liquidity or tax reasons.

Derivative holdings (Form 4 Table II) Options, RSUs and convertible securities reported on Form 4 Table II.

06
DateTickerSecurityUnderlying Exercise priceExpirationSharesA/D
Aug. 11, 2026 WLK Employee Option (right to buy) Common Stock (38,873) $61.86 Feb. 17, 2027 38,873 Disposed
Feb. 20, 2026 WLK Restricted Stock Units Common Stock (14,945) · · 14,945 Acquired
Feb. 20, 2026 WLK Employee Option (right to buy) Common Stock (54,763) $94.48 Feb. 20, 2036 54,763 Acquired
Feb. 17, 2026 WLK Restricted Stock Units Common Stock (16,555) · · 16,555 Disposed
Feb. 21, 2025 WLK Restricted Stock Units Common Stock (12,322) · · 12,322 Acquired
Feb. 21, 2025 WLK Employee Option (right to buy) Common Stock (37,172) $110.15 Feb. 21, 2035 37,172 Acquired
Feb. 18, 2025 WLK Restricted Stock Units Common Stock (17,972) · · 17,972 Disposed
Aug. 16, 2024 WLK Employee Option (right to buy) Common Stock (45,298) $68.09 Aug. 20, 2025 45,298 Disposed
Feb. 19, 2024 WLK Restricted Stock Units Common Stock (19,810) · · 19,810 Disposed
Feb. 16, 2024 WLK Employee Option (right to buy) Common Stock (44,324) $144.49 Feb. 16, 2034 44,324 Acquired
Feb. 16, 2024 WLK Restricted Stock Units Common Stock (16,010) · · 16,010 Acquired
Aug. 31, 2023 WLK Employee Option (right to buy) Common Stock (19,988) $63.98 Feb. 14, 2024 19,988 Acquired
Aug. 30, 2023 WLK Employee Option (right to buy) Common Stock (20,000) $63.98 Feb. 14, 2024 20,000 Acquired
Feb. 17, 2023 WLK Employee Option (right to buy) Common Stock (45,196) $122.65 Feb. 17, 2033 45,196 Acquired
Feb. 17, 2023 WLK Restricted Stock Units Common Stock (16,555) · · 16,555 Acquired
Feb. 14, 2023 WLK Restricted Stock Units Common Stock (26,048) · · 26,048 Disposed
May 19, 2022 WLK Employee Option (right to buy) Common Stock (37,876) $45.70 Feb. 15, 2023 37,876 Disposed
Feb. 18, 2022 WLK Employee Option (right to buy) Common Stock (56,819) $108.12 Feb. 18, 2032 56,819 Acquired
Feb. 18, 2022 WLK Restricted Stock Units Common Stock (17,972) · · 17,972 Acquired
Feb. 15, 2022 WLK Restricted Stock Units Common Stock (18,354) · · 18,354 Disposed
Dec. 2, 2021 WLK Employee Option (right to buy) Common Stock (30,787) $30.05 Feb. 17, 2022 30,787 Disposed
Dec. 1, 2021 WLK Employee Option (right to buy) Common Stock (30,787) $30.05 Feb. 17, 2022 30,787 Disposed
Feb. 19, 2021 WLK Employee Option (right to buy) Common Stock (68,074) $86.54 Feb. 19, 2031 68,074 Acquired
Feb. 19, 2021 WLK Restricted Stock Units Common Stock (19,810) · · 19,810 Acquired
Feb. 16, 2021 WLK Restricted Stock Units Common Stock (11,983) · · 11,983 Disposed
Feb. 14, 2021 WLK Restricted Stock Units Common Stock (3,966) · · 3,966 Disposed
Feb. 14, 2021 WLK Restricted Stock Units Common Stock (3,966) · · 3,966 Disposed
Nov. 6, 2020 WLK Employee Option (right to buy) Common Stock (55,148) $22.92 Feb. 18, 2021 55,148 Disposed
Feb. 26, 2020 WLK Employee Option (right to buy) Common Stock (57,800) $10.26 Feb. 26, 2020 57,800 Disposed
Feb. 21, 2020 WLK Employee Option (right to buy) Common Stock (68,698) $10.26 Feb. 26, 2020 68,698 Disposed
Feb. 17, 2020 WLK Restricted Stock Units Common Stock (19,902) · · 19,902 Disposed
Feb. 14, 2020 WLK Employee Option (right to buy) Common Stock (110,186) $65.81 Feb. 14, 2030 110,186 Acquired
Feb. 14, 2020 WLK Restricted Stock Units Common Stock (26,048) · · 26,048 Acquired
Feb. 14, 2020 WLK Restricted Stock Units Common Stock (3,966) · · 3,966 Acquired
Feb. 18, 2019 WLK Restricted Stock Units Common Stock (21,454) · · 21,454 Disposed
Feb. 15, 2019 WLK Employee Option (right to buy) Common Stock (69,708) $79.83 Feb. 15, 2029 69,708 Acquired
Feb. 15, 2019 WLK Restricted Stock Units Common Stock (18,354) · · 18,354 Acquired
Nov. 16, 2018 WLK Employee Option (right to buy) Common Stock (30,640) $7.12 Feb. 13, 2019 30,640 Disposed
Nov. 15, 2018 WLK Employee Option (right to buy) Common Stock (30,640) $7.12 Feb. 13, 2019 30,640 Disposed
Nov. 14, 2018 WLK Employee Option (right to buy) Common Stock (30,639) $7.12 Feb. 13, 2019 30,639 Disposed
Nov. 13, 2018 WLK Employee Option (right to buy) Common Stock (25,000) $7.12 Feb. 13, 2019 25,000 Disposed
Nov. 12, 2018 WLK Employee Option (right to buy) Common Stock (38,973) $7.12 Feb. 13, 2019 38,973 Disposed
Feb. 20, 2018 WLK Restricted Stock Units Common Stock (13,585) · · 13,585 Disposed
Feb. 16, 2018 WLK Restricted Stock Units Common Stock (11,983) · · 11,983 Acquired
Feb. 16, 2018 WLK Employee Option (right to buy) Common Stock (44,647) $107.75 Feb. 16, 2028 44,647 Acquired
Nov. 29, 2017 WLK Employee Option (right to buy) Common Stock (16,844) $9.64 Feb. 15, 2018 16,844 Disposed
Nov. 28, 2017 WLK Employee Option (right to buy) Common Stock (25,000) $9.64 Feb. 15, 2018 25,000 Disposed
Nov. 27, 2017 WLK Employee Option (right to buy) Common Stock (25,000) $9.64 Feb. 15, 2018 25,000 Disposed
Nov. 24, 2017 WLK Employee Option (right to buy) Common Stock (20,000) $9.64 Feb. 15, 2018 20,000 Disposed
Nov. 22, 2017 WLK Employee Option (right to buy) Common Stock (25,000) $9.64 Feb. 15, 2018 25,000 Disposed
Nov. 21, 2017 WLK Employee Option (right to buy) Common Stock (25,000) $9.64 Feb. 15, 2018 25,000 Disposed
Feb. 23, 2017 WLK Employee Option (right to buy) Common Stock (42,180) $15.80 Feb. 23, 2017 42,180 Disposed
Feb. 17, 2017 WLK Restricted Stock Units Common Stock (19,902) · · 19,902 Acquired
Feb. 17, 2017 WLK Employee Option (right to buy) Common Stock (77,746) $61.86 Feb. 17, 2027 77,746 Acquired
Feb. 14, 2017 WLK Restricted Stock Units Common Stock (12,838) · · 12,838 Disposed
Feb. 18, 2016 WLK Restricted Stock Units Common Stock (21,454) · · 21,454 Acquired
Feb. 18, 2016 WLK Employee Option (right to buy) Common Stock (81,673) $44.42 Feb. 18, 2026 81,673 Acquired
Feb. 15, 2016 WLK Restricted Stock Units Common Stock (14,246) · · 14,246 Disposed
Feb. 20, 2015 WLK Restricted Stock Units Common Stock (13,585) · · 13,585 Acquired
Feb. 20, 2015 WLK Employee Option (right to buy) Common Stock (45,298) $68.09 Feb. 20, 2025 45,298 Acquired
Feb. 14, 2014 WLK Restricted Stock Units Common Stock (6,419) · · 6,419 Acquired
Feb. 14, 2014 WLK Employee Option (right to buy) Common Stock (19,994) $127.96 Feb. 14, 2024 19,994 Acquired
Feb. 15, 2013 WLK Restricted Stock Units Common Stock (7,123) · · 7,123 Acquired
Feb. 15, 2013 WLK Employee Option (right to buy) Common Stock (18,938) $91.40 Feb. 15, 2023 18,938 Acquired
Nov. 26, 2012 WLK Employee Option (right to buy) Common Stock (42,579) $14.24 Feb. 13, 2019 42,579 Acquired
Nov. 26, 2012 WLK Employee Option (right to buy) Common Stock (4,514) $36.10 March 15, 2016 4,514 Acquired
Nov. 26, 2012 WLK Employee Option (right to buy) Common Stock (8,547) $27.22 Aug. 31, 2015 8,547 Acquired
Nov. 26, 2012 WLK Employee Option (right to buy) Common Stock (35,400) $14.50 Aug. 16, 2014 35,400 Acquired
Nov. 23, 2012 WLK Employee Option (right to buy) Common Stock (20,000) $14.24 Feb. 13, 2019 20,000 Acquired
Nov. 23, 2012 WLK Employee Option (right to buy) Common Stock (5,000) $36.10 March 15, 2016 5,000 Acquired
Nov. 23, 2012 WLK Employee Option (right to buy) Common Stock (5,000) $27.22 Aug. 31, 2015 5,000 Acquired
Nov. 23, 2012 WLK Employee Option (right to buy) Common Stock (9,000) $14.50 Aug. 16, 2014 9,000 Acquired
Feb. 17, 2012 WLK Employee Option (right to buy) Common Stock (24,629) $60.10 Feb. 17, 2022 24,629 Acquired
Feb. 17, 2012 WLK Employee Option (right to buy) Common Stock (30,787) $60.10 Feb. 17, 2022 30,787 Acquired
Feb. 18, 2011 WLK Employee Option (right to buy) Common Stock (20,672) $45.83 Feb. 18, 2021 20,672 Acquired
Feb. 18, 2011 WLK Employee Option (right to buy) Common Stock (27,574) $45.83 Feb. 18, 2021 27,574 Acquired
Feb. 26, 2010 WLK Employee Option (right to buy) Common Stock (47,390) $20.52 Feb. 26, 2020 47,390 Acquired
Feb. 26, 2010 WLK Employee Option (right to buy) Common Stock (63,249) $20.52 Feb. 26, 2020 63,249 Acquired
Feb. 13, 2009 WLK Employee Option (right to buy) Common Stock (140,525) $14.24 Feb. 13, 2019 140,525 Acquired
Feb. 13, 2009 WLK Employee Option (right to buy) Common Stock (105,291) $14.24 Feb. 13, 2019 105,291 Acquired
Feb. 19, 2008 WLK Employee Option (right to buy) Common Stock (49,007) $19.29 Feb. 15, 2018 49,007 Acquired
Feb. 19, 2008 WLK Employee Option (right to buy) Common Stock (68,422) $19.29 Feb. 15, 2018 68,422 Acquired
March 2, 2007 WLK Employee Option (right to buy) Common Stock (15,488) $31.61 Feb. 23, 2017 15,488 Acquired
March 2, 2007 WLK Employee Option (right to buy) Common Stock (21,090) $31.61 Feb. 23, 2017 21,090 Acquired
March 20, 2006 WLK Employee Option (right to buy) Common Stock (6,977) $36.10 March 15, 2016 6,977 Acquired
March 20, 2006 WLK Employee Option (right to buy) Common Stock (9,514) $36.10 March 15, 2016 9,514 Acquired
Sept. 9, 2005 WLK Employee Option (right to buy) Common Stock (9,934) $27.22 Aug. 31, 2015 9,934 Acquired
Sept. 9, 2005 WLK Employee Option (right to buy) Common Stock (13,547) $27.22 Aug. 31, 2015 13,547 Acquired
Aug. 16, 2004 WLK Incentive Stock Option Common Stock (35,300) $14.50 Aug. 16, 2014 35,300 Acquired
Aug. 16, 2004 WLK Incentive Stock Option Common Stock (44,400) $14.50 Aug. 16, 2014 44,400 Acquired

Exercise/conversion price is blank when not applicable (e.g. RSUs).

Initial ownership (Form 3) 2 holdings

07

Securities held when first becoming an insider, per SEC Form 3.

DateTickerSecuritySharesOwnership
July 29, 2014 WLKP Common Units (Limited Partner Interests) 1,436,115 Indirect
July 29, 2014 WLKP Subordinated Units (Limited Partner Interests)→ Common Units (12,686,115) 12,686,115 Indirect

Compensation (DEF 14A)

08

Matched by name from proxy statements (DEF 14A) — verify against the filing.

WLK

Fiscal yearSalaryBonusStock awards Option awardsNon-equity incentivePension changeOtherTotal
2013 $891,333 · $651,000 $651,000 $3,508,239 · $51,993 $5,753,566
2012 $862,500 · · · $3,121,587 · $233,583 $5,658,046
2011 $828,333 · · · $1,602,793 · $50,477 $3,541,603

WLKP

CEO
Fiscal yearSalaryBonusStock awards Option awardsNon-equity incentivePension changeOtherTotal
2023 $1,256,000 · · · · · · $125,600

Figures from the Summary Compensation Table of the company's proxy statement (DEF 14A). Compensation is not a recommendation.