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WESTLAKE CORP

WLK Net buying
CIK 0001262823 #932 in the set updated 17 Sep 2026
Bought (120 mo)
$50.39M
out of their own pocket, the only kind of buying there is
Sold (120 mo)
$128.08M
$0.00 on a plan · $101.18M straight out of an exercise
Sold at will
$26.90M
51 of 154 sales
Net
−$77.69M
+$23.49M against sales at will

By person

30 insiders · 236 transactions
Insider
Role
Bought
Sold
Net
Holding
Of company
Worth
Change
TTWFGP LLC entity
10% owner
$49.98M (37)
—
+$49.98M
47,400,277
37.09%
$3.81B
+3.0%
Chao Albert
Executive Chairman
$258.63K (1)
$49.92M (51) scheduled
−$49.66M
642,880
0.5030%
$51.70M
+140.2%
Bender Mark Steven
EVP & CFO
—
$29.78M (39) scheduled
−$29.78M
35,895
0.0281%
$2.89M
−36.5%
Chao James
Senior Chairman
—
$13.37M (8) scheduled
−$13.37M
49,774
0.0389%
$4.00M
−54.9%
Buesinger Robert F.
EVP, PEM Segment Head
$7.75K (1)
$13.32M (21) scheduled
−$13.32M
34,482
0.0270%
$2.77M
+82,000%
Teel Lawrence E.
EVP and Special Advisor to CEO
—
$5.15M (5) scheduled
−$5.15M
4,903
0.0038%
$394.30K
+463.6%
Kenner Andrew
SVP, Operations
—
$3.86M (3) scheduled
−$3.86M
20,362
0.0159%
$1.64M
+85.5%
Mangieri George J
VP & Chief Accounting Officer
—
$2.82M (7) scheduled
−$2.82M
4,671
0.0037%
$375.64K
−74.3%
Ederington L. Benjamin
EVP, Legal & External Affairs
—
$2.53M (3) scheduled
−$2.53M
80,158
0.0627%
$6.45M
—
Kearns Roger L.
EVP and COO
$149.45K (1)
$2.44M (3) scheduled
−$2.30M
45,785
0.0358%
$3.68M
—
LUKENS MAX L
Director
—
$1.95M (2)
−$1.95M
9,122
0.0071%
$733.59K
−51.7%
Mattina Michael J.
Sr. VP, Polyethylene
—
$982.78K (1) scheduled
−$982.78K
6,506
0.0051%
$523.21K
+7.3%
BLAKELY ROBERT T
Director
—
$851.41K (2)
−$851.41K
10,989
0.0086%
$883.74K
−22.1%
Chao David Tsung-Hung
Director
—
$584.39K (3)
−$584.39K
30,503
0.0239%
$2.45M
+4,571%
Zoeller Johnathan Stevan
VP and CAO
—
$256.55K (3) scheduled
−$256.55K
4,416
0.0035%
$355.13K
—
RILEY H JOHN JR
Director
—
$232.62K (1)
−$232.62K
22,652
0.0177%
$1.82M
+9.5%
Jenkins Dorothy C
Director
—
$30.38K (2) scheduled
−$30.38K
73,778
0.0577%
$5.93M
+87.9%
Chao Catherine T.
Director
—
—
—
27,171
0.0213%
$2.19M
+1,259%
NORTHCUTT R BRUCE
Director
—
—
—
23,351
0.0183%
$1.88M
+658.9%
Graff Michael J
Director
—
—
—
23,310
0.0182%
$1.87M
+657.6%
Janssens Thomas J.
SVP, Ops - PEM & Corp Logistic
—
—
—
17,127
0.0134%
$1.38M
+195.6%
Sheets Jeffrey Wayne
Director
—
—
—
14,927
0.0117%
$1.20M
—
Lubel Kimberly S
Director
—
—
—
13,821
0.0108%
$1.11M
—
Szwejbka Scott Thomas
SVP, HIP Segment Head
—
—
—
13,773
0.0108%
$1.11M
+136.7%
MCCOLLUM MARK A
Director
—
—
—
11,824
0.0093%
$950.89K
—
Haas Marius
Director
—
—
—
11,631
0.0091%
$935.37K
—
Chao John Tsung-chen
Director
—
—
—
7,888
0.0062%
$634.35K
—
Sabat Carolyn Chao
Director
—
—
—
5,748
0.0045%
$462.25K
—
Holy Jeffrey Adam
VP and CAO
—
—
—
5,124
0.0040%
$412.07K
+70.8%
CREGG ROGER A
Director
—
—
—
3,507
0.0027%
$282.03K
—

Individual transactions

51
Insider
Date
Role
Action
Shares
Price
Amount
Bender Mark Steven
27 Mar 2026
EVP & CFO
Sell
16,413
$112.54
$1.85M
Buesinger Robert F.
27 Mar 2026
EVP, PEM Segment Head
Sell
4,000
$115.25
$461.00K
Buesinger Robert F.
27 May 2025
EVP, PEM Segment Head
Sell indirect
83
$72.70
$6.03K
Chao David Tsung-Hung
29 Nov 2024
Director
Sell
1,750
$129.08
$225.89K
Chao David Tsung-Hung
22 Nov 2024
Director
Sell
1,750
$130.00
$227.50K
Buesinger Robert F.
9 May 2024
EVP, HIP, IT & Digital
Sell
3,500
$158.50
$554.75K
Bender Mark Steven
3 May 2024
EVP & CFO
Sell
4,950
$152.19
$753.34K
Buesinger Robert F.
15 Mar 2024
EVP, HIP, IT & Digital
Sell
3,878
$144.50
$560.37K
Buesinger Robert F.
13 Mar 2024
EVP, HIP, IT & Digital
Sell
122
$144.50
$17.63K
Bender Mark Steven
6 Mar 2024
EVP & CFO
Sell
4,804
$141.02
$677.46K
Bender Mark Steven
26 Feb 2024
EVP & CFO
Sell
4,854
$137.57
$667.76K
Buesinger Robert F.
15 Nov 2023
EVP, HIP, IT & Digital
Sell
4,215
$130.50
$550.06K
Chao David Tsung-Hung
23 Aug 2023
Director
Sell
1,000
$131.00
$131.00K
Buesinger Robert F.
31 Aug 2022
EVP, HIP, IT & Digital
Sell
1,000
$98.94
$98.94K
Zoeller Johnathan Stevan
26 Aug 2022
VP & Chief Accounting Officer
Sell
542
$107.08
$58.04K
Buesinger Robert F.
9 Mar 2022
EVP, HIP, IT & Digital
Sell
2,730
$115.55
$315.45K
Bender Mark Steven
11 Nov 2021
EVP and CFO
Sell
2,369
$101.57
$240.62K
Bender Mark Steven
8 Nov 2021
EVP and CFO
Sell
631
$100.77
$63.59K
Bender Mark Steven
5 Nov 2021
EVP and CFO
Sell
6,356
$98.80
$627.95K
Buesinger Robert F.
10 May 2021
EVP, Vinyl Products
Sell
5,000
$105.00
$525.00K
Kenner Andrew
23 Nov 2020
SVP - Chemical Manufacturing
Sell
5,924
$74.75
$442.82K
Bender Mark Steven
6 Nov 2020
EVP and CFO
Sell
1,600
$74.79
$119.67K
Mangieri George J
8 Nov 2019
SVP & Chief Accounting Officer
Sell
1,583
$75.05
$118.80K
RILEY H JOHN JR
19 Mar 2019
Director
Sell
3,327
$69.92
$232.62K
Chao James
24 May 2018
Chairman
Sell
33,305
$120.69
$4.02M
Buesinger Robert F.
15 May 2018
EVP, Vinyl Products
Sell
1,447
$118.88
$172.01K
Mangieri George J
5 Mar 2018
SVP & Chief Accounting Officer
Sell
2,161
$113.41
$245.08K
BLAKELY ROBERT T
27 Feb 2018
Director
Sell
4,038
$111.00
$448.22K
Bender Mark Steven
26 Feb 2018
EVP and CFO
Sell
3,500
$112.06
$392.21K
Bender Mark Steven
26 Feb 2018
EVP and CFO
Sell
1,500
$110.84
$166.26K
Bender Mark Steven
22 Feb 2018
EVP and CFO
Sell
4,000
$110.97
$443.88K
LUKENS MAX L
22 Feb 2018
Director
Sell
100
$111.41
$11.14K
LUKENS MAX L
22 Feb 2018
Director
Sell
17,458
$110.93
$1.94M
Bender Mark Steven
22 Feb 2018
EVP and CFO
Sell
2,000
$110.64
$221.27K
Buesinger Robert F.
1 Dec 2017
EVP, Vinyls Products
Sell
2,674
$98.50
$263.39K
Bender Mark Steven
21 Nov 2017
EVP and CFO
Sell
20,382
$94.27
$1.92M
BLAKELY ROBERT T
14 Nov 2017
Director
Sell
4,367
$92.33
$403.19K
Bender Mark Steven
15 Aug 2017
Executive VP & CFO
Sell
13,794
$70.22
$968.62K
Mangieri George J
17 May 2017
VP & Chief Accounting Officer
Sell
6,578
$62.21
$409.20K
Bender Mark Steven
10 Mar 2017
Sr VP, CFO and Treasurer
Sell
12,000
$64.32
$771.78K
Chao Albert
17 Nov 2016
President & CEO
Sell indirect
300
$54.57
$16.37K
Chao Albert
17 Nov 2016
President & CEO
Sell indirect
9,700
$53.82
$522.09K
Chao James
17 Nov 2016
Chairman
Sell indirect
300
$54.57
$16.37K
Chao James
17 Nov 2016
Chairman
Sell indirect
9,700
$53.82
$522.09K
Chao Albert
16 Nov 2016
President & CEO
Sell indirect
10,000
$54.45
$544.45K
Chao James
16 Nov 2016
Chairman
Sell indirect
10,000
$54.45
$544.45K
Chao Albert
15 Nov 2016
President & CEO
Sell indirect
10,000
$53.06
$530.60K
Chao James
15 Nov 2016
Chairman
Sell indirect
10,000
$53.06
$530.60K
Chao Albert
14 Nov 2016
President & CEO
Sell indirect
10,000
$52.84
$528.44K
Chao James
14 Nov 2016
Chairman
Sell indirect
10,000
$52.84
$528.44K
Mangieri George J
11 Nov 2016
VP & Chief Accounting Officer
Sell
5,696
$52.91
$301.37K
Show all 236 transactions →

What was left out

Form 4 filings counted 527
Amendments (4/A) skipped 24
Filings about a different issuer 1
Unreadable filings 0
Joint filings 0
Sales on a Rule 10b5-1 plan 0
Sales straight out of an exercise 103
Sales at will 51
Transactions with no price 0
Shares from compensation/vesting 4,040,969
Sales filed before the plan box existed 38
History held since 6 Sep 2016