Westlake Corporation
DE ˙ DB ˙ US9604131022
74,44 € ↑1,62 (2,22%)
2026-06-05
DEL PRIS
SecurityDE:UEO / Westlake Corporation
InstitutionMorgan Stanley
Latest Disclosed Ownership486,508 shares
Latest Disclosed Value $ 56,834,106
Morgan Stanley reports 35.95% decrease in ownership of UEO / Westlake Corporation

On May 15, 2026 - Morgan Stanley filed a 13F-HR form disclosing ownership of 486,508 shares of Westlake Corporation (DE:UEO) valued at $49,137,308 USD as of March 31, 2026. The entity filed a previous 13F-HR/A on May 27, 2026 disclosing 759,623 shares of Westlake Corporation. This represents a change in shares of -35.95% during the quarter. The current value of the position is $36,215,656 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

Upgrade to unlock premium data and export to Excel .

Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-05-15 2026-03-31 13F WESTLAKE COM 960413102 486,508 -273,115 -35.95 56,834 1.19 0.0034
2026-05-27 2025-12-31 13F/A-1 WESTLAKE COM 960413102 759,623 -56,006 -6.87 56,167 -10.64 0.0034
2026-02-13 2025-12-31 13F WESTLAKE COM 960413102 759,623 -56,006 56,167 0.0034
2026-05-27 2025-09-30 13F/A-1 WESTLAKE COM 960413102 815,629 353,141 76.36 62,853 78.98 0.0038
2025-11-14 2025-09-30 13F WESTLAKE COM 960413102 815,629 353,141 62,853 0.0038
2025-08-15 2025-06-30 13F WESTLAKE COM 960413102 462,488 199,932 76.15 35,117 33.71 0.0023
2025-05-15 2025-03-31 13F WESTLAKE COM 960413102 262,556 -38,994 -12.93 26,264 -24.03 0.0019
2025-05-15 2024-12-31 13F/A-1 WESTLAKE COM 960413102 301,550 -23,912 -7.35 34,573 -29.32 0.0024
2025-02-14 2024-12-31 13F WESTLAKE COM 960413102 301,550 -23,912 34,573 0.0024
2025-05-14 2024-09-30 13F/A-2 WESTLAKE COM 960413102 325,462 1,245 0.38 48,914 4.17 0.0035
2025-02-14 2024-09-30 13F/A-1 WESTLAKE COM 960413102 325,462 1,245 48,914 0.0035
2024-11-14 2024-09-30 13F WESTLAKE COM 960413102 325,462 1,245 48,914 0.0035
2025-05-14 2024-06-30 13F/A-2 WESTLAKE COM 960413102 324,217 6,226 1.96 46,953 -3.37 0.0036
2024-10-17 2024-06-30 13F/A-1 WESTLAKE COM 960413102 324,217 6,226 46,953 0.0036
2024-08-14 2024-06-30 13F WESTLAKE COM 960413102 324,217 6,226 46,953 0.0036
2024-10-17 2024-03-31 13F/A-2 WESTLAKE COM 960413102 317,991 62,094 24.27 48,589 35.67 0.0039
2024-08-16 2024-03-31 13F/A-1 WESTLAKE COM 960413102 317,991 62,094 48,589 0.0005
2024-05-15 2024-03-31 13F WESTLAKE COM 960413102 317,991 62,094 48,589 0.0039
2024-08-16 2023-12-31 13F/A-1 WESTLAKE COM 960413102 255,897 -74,126 -22.46 35,816 -12.95 0.0032
2024-02-13 2023-12-31 13F WESTLAKE COM 960413102 255,897 -74,126 35,816 0.0032
2023-11-15 2023-09-30 13F WESTLAKE COM 960413102 330,023 16,237 5.17 41,144 9.75 0.0042
2023-08-14 2023-06-30 13F WESTLAKE COM 960413102 313,786 -18,112 -5.46 37,488 -2.61 0.0037
2023-05-15 2023-03-31 13F WESTLAKE COM 960413102 331,898 11,923 3.73 38,494 17.32 0.0041
2023-02-14 2022-12-31 13F WESTLAKE COM 960413102 319,975 -276,212 -46.33 32,810 -36.65 0.0037
2022-11-14 2022-09-30 13F WESTLAKE COM 960413102 596,187 -64,389 -9.75 51,795 -20.01 0.0071
2022-10-27 2022-06-30 13F/A-1 WESTLAKE COM 960413102 660,576 200,698 43.64 64,750 14.10 0.0084
2022-08-15 2022-06-30 13F WESTLAKE COM 960413102 660,576 200,698 64,750 0.0084
2022-10-27 2022-03-31 13F/A-1 WESTLAKE COM 960413102 459,878 -199,364 -30.24 56,747 -11.38 0.0077
2022-05-13 2022-03-31 13F WESTLAKE COM 960413102 459,878 -199,364 56,747 0.0077
2022-02-14 2021-12-31 13F WESTLAKE CHEM COM 960413102 659,242 131,553 24.93 64,033 33.14 0.0079
2021-11-15 2021-09-30 13F WESTLAKE CHEM COM 960413102 527,689 -35,521 -6.31 48,094 -5.21 0.0065
2021-08-23 2021-06-30 13F/A-1 WESTLAKE CHEM COM 960413102 563,210 331,277 142.83 50,739 146.38 0.0067
2021-08-16 2021-06-30 13F WESTLAKE CHEM COM 960413102 563,210 331,277 50,739 0.0014
2021-05-17 2021-03-31 13F WESTLAKE CHEM COM 960413102 231,933 143,900 163.46 20,594 186.66 0.0030
2021-02-16 2020-12-31 13F WESTLAKE CHEM COM 960413102 88,033 8,415 10.57 7,184 42.71 0.0011
2020-11-13 2020-09-30 13F WESTLAKE CHEM COM 960413102 79,618 -15,002 -15.85 5,034 -0.87 0.0010
2020-08-14 2020-06-30 13F WESTLAKE CHEM COM 960413102 94,620 -30,144 -24.16 5,078 6.64 0.0011
2020-05-26 2020-03-31 13F/A-1 WESTLAKE CHEM COM 960413102 124,764 16,847 15.61 4,762 -37.10 0.0013
2020-05-15 2020-03-31 13F WESTLAKE CHEM COM 960413102 124,764 16,847 4,762 365.8209
2020-02-14 2019-12-31 13F WESTLAKE CHEM COM 960413102 107,917 18,032 20.06 7,571 28.58 0.0018
2019-11-14 2019-09-30 13F WESTLAKE CHEM COM 960413102 89,885 -22,368 -19.93 5,888 -24.48 0.0016
2019-08-14 2019-06-30 13F WESTLAKE CHEM COM 960413102 112,253 -20,592 -15.50 7,797 -13.51 0.0021
2019-05-15 2019-03-31 13F WESTLAKE CHEM COM 960413102 132,845 -22,670 -14.58 9,015 -12.39 0.0026
2019-02-14 2018-12-31 13F WESTLAKE CHEM COM 960413102 155,515 -388,831 -71.43 10,290 -77.25 0.0031
2019-04-23 2018-09-30 13F/A-2 WESTLAKE CHEM COM 960413102 544,346 375,952 223.26 45,240 149.61 0.0113
2018-11-20 2018-09-30 13F/A-1 WESTLAKE CHEM COM 960413102 544,346 0 45,240 0.0113
2018-11-14 2018-09-30 13F WESTLAKE CHEM COM 960413102 544,346 375,952 45,240
2019-04-23 2018-06-30 13F/A-1 WESTLAKE CHEM COM 960413102 168,394 98,268 140.13 18,124 132.57 0.0049
2018-08-14 2018-06-30 13F WESTLAKE CHEM COM 960413102 168,394 98,268 18,124
2019-04-23 2018-03-31 13F/A-1 WESTLAKE CHEM COM 960413102 70,126 20,450 41.17 7,793 47.23 0.0022
2018-05-14 2018-03-31 13F WESTLAKE CHEM COM 960413102 70,126 20,450 7,793
2019-04-23 2017-12-31 13F/A-1 WESTLAKE CHEM COM 960413102 49,676 -40,441 -44.88 5,293 -29.31 0.0014
2018-02-14 2017-12-31 13F WESTLAKE CHEM COM 960413102 49,676 -40,441 5,293
2017-11-14 2017-09-30 13F WESTLAKE CHEM COM 960413102 90,117 55,788 162.51 7,488 229.43 0.0022
2017-08-11 2017-06-30 13F WESTLAKE CHEM COM 960413102 34,329 8,301 31.89 2,273 32.31 0.0007
2017-05-22 2017-03-31 13F/A-1 WESTLAKE CHEM COM 960413102 26,028 3,413 15.09 1,718 35.70 0.0005
2017-05-12 2017-03-31 13F WESTLAKE CHEM COM 960413102 26,028 1,718
2017-02-22 2016-12-31 13F/A-1 WESTLAKE CHEM COM 960413102 22,615 -763 -3.26 1,266 1.20 0.0004
2017-02-13 2016-12-31 13F WESTLAKE CHEM COM 960413102 22,615 1,266
2016-11-10 2016-09-30 13F WESTLAKE CHEM COM 960413102 23,378 -442,141 -94.98 1,251 -93.74 0.0004
2016-08-12 2016-06-30 13F WESTLAKE CHEM COM 960413102 465,519 72,254 18.37 19,981 9.74 0.0072
2016-05-12 2016-03-31 13F WESTLAKE CHEM COM 960413102 393,265 355,210 933.41 18,207 780.84 0.0070
2016-02-09 2015-12-31 13F WESTLAKE CHEM COM 960413102 38,055 12,435 48.54 2,067 55.41 0.0007
2016-02-08 2015-09-30 13F/A-1 WESTLAKE CHEM COM 960413102 25,620 -133,821 -83.93 1,330 -87.84 0.0005
2015-11-09 2015-09-30 13F WESTLAKE CHEM COM 960413102 25,620 1,330
2015-08-12 2015-06-30 13F WESTLAKE CHEM COM 960413102 159,441 58,071 57.29 10,936 49.95 0.0038
2015-05-14 2015-03-31 13F WESTLAKE CHEM COM 960413102 101,370 -232,697 -69.66 7,293 -64.27 0.0027
2015-02-13 2014-12-31 13F WESTLAKE CHEM COM 960413102 334,067 16,550 5.21 20,409 -25.77 0.0075
2014-12-16 2014-09-30 13F/A-1 WESTLAKE CHEM COM 960413102 317,517 -91,483 -22.37 27,494 1.57 0.0106
2014-11-14 2014-09-30 13F WESTLAKE CHEM COM 960413102 317,517 27,494
2014-05-13 2014-03-31 13F WESTLAKE CHEM COM 960413102 409,000 337,484 471.90 27,068 209.99 0.0113
2014-02-13 2013-12-31 13F WESTLAKE CHEM COM 960413102 71,516 34,229 91.80 8,732 123.78 0.0037
2013-11-13 2013-09-30 13F WESTLAKE CHEM COM 960413102 37,287 -92,510 -71.27 3,902 -68.82 0.0018
2013-08-08 2013-06-30 13F WESTLAKE CHEM COM 960413102 129,797 129,797 12,513 0.0063
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.