LyondellBasell Industries N.V.
US ˙ NYSE

SecurityLYB / LyondellBasell Industries N.V.
InstitutionSei Investments Co
Latest Disclosed Ownership88,267 shares
Latest Disclosed Value $ 3,822,045
Sei Investments Co reports 21.86% decrease in ownership of LYB / LyondellBasell Industries N.V.

On February 13, 2026 - Sei Investments Co filed a 13F-HR form disclosing ownership of 88,267 shares of LyondellBasell Industries N.V. (US:LYB) valued at $3,821,961 USD as of December 31, 2025. The entity filed a previous 13F-HR on November 13, 2025 disclosing 112,962 shares of LyondellBasell Industries N.V.. This represents a change in shares of -21.86% during the quarter. The current value of the position is $5,940,369 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.

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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)
2026-02-13 2025-12-31 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 88,267 -24,695 -21.86 3,822 -31.01 0.0038
2025-11-13 2025-09-30 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 112,962 -8,013 -6.62 5,540 -20.86 0.0060
2025-08-14 2025-06-30 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 120,975 5,772 5.01 7,001 -13.67 0.0081
2025-05-14 2025-03-31 13F/A-1 LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 115,203 -5,872 -4.85 8,108 -9.83 0.0104
2025-05-13 2025-03-31 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 113,820 -7,255 8,341 0.0091
2025-02-11 2024-12-31 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 121,075 10,833 9.83 8,993 -14.95 0.0115
2024-11-12 2024-09-30 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 110,242 923 0.84 10,572 1.10 0.0137
2024-08-13 2024-06-30 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 109,319 -12,611 -10.34 10,457 -16.15 0.0148
2024-05-07 2024-03-31 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 121,930 -8,103 -6.23 12,471 0.86 0.0183
2024-02-14 2023-12-31 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 130,033 9,695 8.06 12,366 8.51 0.0199
2023-11-14 2023-09-30 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 120,338 754 0.63 11,396 3.78 0.0205
2023-08-11 2023-06-30 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 119,584 -10,730 -8.23 10,981 -10.26 0.0192
2023-05-12 2023-03-31 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 130,314 30,470 30.52 12,236 47.59 0.0227
2023-02-10 2022-12-31 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 99,844 -13,380 -11.82 8,291 -2.75 0.0184
2022-11-14 2022-09-30 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 113,224 50,840 81.50 8,524 54.93 0.0190
2022-08-15 2022-06-30 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 62,384 21,022 50.82 5,502 26.51 0.0119
2022-05-13 2022-03-31 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 41,362 8,596 26.23 4,349 42.50 0.0087
2022-02-14 2021-12-31 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 32,766 -5,087 -13.44 3,052 -15.22 0.0057
2021-11-12 2021-09-30 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 37,853 -17,991 -32.22 3,600 -37.76 0.0076
2021-08-06 2021-06-30 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 55,844 13,131 30.74 5,784 34.79 0.0128
2021-05-12 2021-03-31 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 42,713 -21,425 -33.40 4,291 -27.33 0.0108
2021-02-08 2020-12-31 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 64,138 -8,661 -11.90 5,905 14.84 0.0153
2020-12-04 2020-09-30 13F/A-1 LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 72,799 3,474 5.01 5,142 11.76 0.0149
2020-11-06 2020-09-30 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 88,963 19,638 6,281 15,123.2515
2020-08-17 2020-06-30 13F/A-1 LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 69,325 26,793 62.99 4,601 115.50 0.0143
2020-08-11 2020-06-30 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 49,143 6,611 3,820 10,361.9533
2020-05-14 2020-03-31 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 42,532 -532 -1.24 2,135 -47.61 0.0078
2020-02-06 2019-12-31 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 43,064 -118 -0.27 4,075 4.73 0.0122
2019-11-12 2019-09-30 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 43,182 -14,235 -24.79 3,891 -21.90 0.0100
2019-08-14 2019-06-30 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 57,417 -5,606 -8.90 4,982 -7.43 0.0163
2019-05-15 2019-03-31 13F LYONDELLBASELL INDUSTRIES N S3 - A - N53745100 63,023 11,094 21.36 5,382 8.20 0.0181
2019-02-13 2018-12-31 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 51,929 5,544 11.95 4,974 4.52 0.0177
2018-11-08 2018-09-30 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 46,385 -39,097 -45.74 4,759 -49.33 0.0172
2018-08-03 2018-06-30 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 85,482 -66,035 -43.58 9,393 -41.34 0.0319
2018-05-11 2018-03-31 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 151,517 -25,639 -14.47 16,013 -18.06 0.0614
2018-02-08 2017-12-31 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 177,156 33,090 22.97 19,543 36.96 0.0679
2017-11-06 2017-09-30 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 144,066 43,878 43.80 14,269 68.76 0.0507
2017-07-31 2017-06-30 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 100,188 -13,756 -12.07 8,455 -18.62 0.0337
2017-05-05 2017-03-31 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 113,944 -29,902 -20.79 10,390 -15.80 0.0455
2017-02-02 2016-12-31 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 143,846 -11,545 -7.43 12,340 -1.54 0.0598
2016-11-04 2016-09-30 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 155,391 -82,402 -34.65 12,533 -29.18 0.0637
2016-08-11 2016-06-30 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 237,793 -687 -0.29 17,697 -13.29 0.1061
2016-05-10 2016-03-31 13F/A-1 LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 238,480 52,333 28.11 20,409 26.17 0.1270
2016-02-03 2015-12-31 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 186,147 43,687 30.67 16,176 36.22 0.0986
2015-11-02 2015-09-30 13F/A-1 LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 142,460 -28,604 -16.72 11,875 -32.94 0.1090
2015-10-30 2015-09-30 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 142,460 11,877
2015-08-07 2015-06-30 13F/A-1 LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 171,064 71,321 71.50 17,709 102.25 0.1601
2015-08-04 2015-06-30 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 171,064 71,321 17,709 0.1601
2015-05-14 2015-03-31 13F/A-1 LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 99,743 -127,985 -56.20 8,756 -51.57 0.0760
2015-05-01 2015-03-31 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 99,743 8,756
2015-02-10 2014-12-31 13F LYONDELLBASELL INDUSTRIES N SHS - A - N53745100 227,728 227,728 18,078 0.1598
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.