William Blair & Company
LYB icon

William Blair & Company’s LyondellBasell Industries LYB Stock Holding History

William Blair & Company’s Portfolio LYB Stock Details LYB Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q1 		$914K Buy
11,340
+3,015
+36% +$179K ﹤0.01% 968
2025
Q4 		$360K Sell
8,325
-2,670
-24% -$121K ﹤0.01% 1246
2025
Q3 		$539K Sell
10,995
-3,985
-27% -$225K ﹤0.01% 1088
2025
Q2 		$867K Sell
14,980
-51,703
-78% -$3.01M ﹤0.01% 937
2025
Q1 		$4.69M Sell
66,683
-2,201
-3% -$166K 0.01% 498
2024
Q4 		$5.12M Buy
68,884
+58,186
+544% +$4.89M 0.01% 493
2024
Q3 		$1.03M Buy
10,698
+1,556
+17% +$149K ﹤0.01% 898
2024
Q2 		$875K Sell
9,142
-64
-0.7% -$6.35K ﹤0.01% 924
2024
Q1 		$942K Sell
9,206
-127
-1% -$12.4K ﹤0.01% 886
2023
Q4 		$887K Buy
9,333
+1,032
+12% +$96.5K ﹤0.01% 893
2023
Q3 		$786K Sell
8,301
-585
-7% -$56.2K ﹤0.01% 914
2023
Q2 		$816K Sell
8,886
-305
-3% -$27.9K ﹤0.01% 911
2023
Q1 		$863K Sell
9,191
-661
-7% -$61.5K ﹤0.01% 876
2022
Q4 		$818K Buy
9,852
+67
+0.7% +$5.49K ﹤0.01% 892
2022
Q3 		$737K Sell
9,785
-1,052
-10% -$88.9K ﹤0.01% 918
2022
Q2 		$948K Buy
10,837
+25
+0.2% +$2.6K ﹤0.01% 864
2022
Q1 		$1.11M Buy
10,812
+107
+1% +$10.7K ﹤0.01% 884
2021
Q4 		$987K Buy
10,705
+412
+4% +$38.2K ﹤0.01% 966
2021
Q3 		$966K Sell
10,293
-918
-8% -$90.1K ﹤0.01% 942
2021
Q2 		$1.15M Sell
11,211
-522
-4% -$56.5K ﹤0.01% 877
2021
Q1 		$1.22M Buy
11,733
+629
+6% +$62.4K ﹤0.01% 838
2020
Q4 		$1.02M Buy
11,104
+4,386
+65% +$357K ﹤0.01% 843
2020
Q3 		$474K Sell
6,718
-328
-5% -$22.7K ﹤0.01% 988
2020
Q2 		$463K Sell
7,046
-806
-10% -$48K ﹤0.01% 963
2020
Q1 		$390K Buy
7,852
+851
+12% +$62.6K ﹤0.01% 938
2019
Q4 		$661K Sell
7,001
-9,207
-57% -$844K ﹤0.01% 899
2019
Q3 		$1.45M Sell
16,208
-785
-5% -$64K 0.01% 660
2019
Q2 		$1.46M Buy
16,993
+2,006
+13% +$171K 0.01% 661
2019
Q1 		$1.26M Buy
14,987
+1,007
+7% +$87K 0.01% 671
2018
Q4 		$1.16M Buy
13,980
+1,389
+11% +$127K 0.01% 654
2018
Q3 		$1.29M Buy
12,591
+141
+1% +$15.4K 0.01% 662
2018
Q2 		$1.37M Buy
12,450
+791
+7% +$86.8K 0.01% 634
2018
Q1 		$1.23M Sell
11,659
-2,931
-20% -$328K 0.01% 651
2017
Q4 		$1.61M Sell
14,590
-92
-0.6% -$9.54K 0.01% 619
2017
Q3 		$1.45M Sell
14,682
-254
-2% -$22.8K 0.01% 621
2017
Q2 		$1.26M Buy
14,936
+6,529
+78% +$542K 0.01% 685
2017
Q1 		$767K Buy
8,407
+91
+1% +$8.3K 0.01% 778
2016
Q4 		$713K Buy
8,316
+2,923
+54% +$245K 0.01% 728
2016
Q3 		$435K Buy
+5,393
New +$417K ﹤0.01% 875

Other funds holding LYB

BlackRock
BlackRock New York $5.72T AUM 30.48% 1-Year Est. Return
Dodge & Cox
Dodge & Cox San Francisco, California $182B AUM 14.68% 1-Year Est. Return
VCM
Vanguard Capital Management Malvern, Pennsylvania $4.04T AUM
State Street
State Street Boston, Massachusetts $2.9T AUM 29.55% 1-Year Est. Return
VPM
Vanguard Portfolio Management Malvern, Pennsylvania $1.91T AUM
Capital World Investors
Capital World Investors Los Angeles, California $733B AUM 35.63% 1-Year Est. Return
Capital Research Global Investors
Capital Research Global Investors Los Angeles, California $645B AUM 30.41% 1-Year Est. Return
Fidelity Investments
Fidelity Investments Boston, Massachusetts $1.9T AUM 41.92% 1-Year Est. Return
Geode Capital Management
Geode Capital Management Boston, Massachusetts $1.61T AUM 30.72% 1-Year Est. Return
Morgan Stanley
Morgan Stanley New York $1.66T AUM 25.57% 1-Year Est. Return

William Blair & Company's LYB Position: Q1 2026 in Review

William Blair & Company increased its LyondellBasell Industries (LYB) stake by 36% in Q1 2026, buying an estimated $179K and bringing the position to 11,340 shares worth $914K. The position accounts for ﹤0.01% of the portfolio, ranked #968.

William Blair & Company first reported a position in LYB in Q3 2016 and has held it in 39 quarters since. The position peaked at $5.12M in Q4 2024. 926 funds tracked by Wall St. Rank hold LYB as of Q1 2026.

  • William Blair & Company held 11,340 shares of LyondellBasell Industries worth $914K as of Q1 2026.
  • William Blair & Company bought 3,015 LyondellBasell Industries shares in Q1 2026, an estimated $179K.
  • LyondellBasell Industries made up ﹤0.01% of William Blair & Company's portfolio in Q1 2026, its #968 holding.
  • William Blair & Company first reported a position in LyondellBasell Industries in Q3 2016 and has held it in 39 quarters since.
  • William Blair & Company's LyondellBasell Industries position peaked at $5.12M in Q4 2024.
  • 926 funds tracked by Wall St. Rank held LyondellBasell Industries as of Q1 2026.

Based on William Blair & Company's 13F filing for Q1 2026, filed 8 May 2026.