Mar 31, 2026 filings. Quarterly 13F reports arrive up to 45 days after quarter end; this register is filed through May 29, 2026.
400 institutional managers reported holding OLN for the quarter ended Mar 31, 2026. Reported positions total over 95% of shares outstanding; the top 10 hold 59%. 99 opened new positions; 69 closed out. Complete ranked register from SEC 13F filings.
| manager | shares | % out | value (Mar 31, 2026 close) | change | held since |
|---|---|---|---|---|---|
| Hotchkis & Wiley Capital Management LLC | 15.08M | 13.26% | $448.6M | trimmed -1.3% | 2022 Q2 |
| BlackRock | 11.49M | 10.09% | $341.6M | trimmed -3.9% | ≤2013 |
| Vanguard Group | 11.37M | 9.99% | $338.2M | unchanged | ≤2013 |
| Dimensional Fund Advisors | 5.63M | 4.95% | $167.4M | added +22.4% | ≤2013 |
| Fuller & Thaler Asset Management, INC. | 5.02M | 4.41% | $149.2M | trimmed -14.7% | 2020 Q3 |
| State Street | 4.80M | 4.22% | $142.8M | added +1.3% | ≤2013 |
| Pzena Investment Management | 4.43M | 3.89% | $131.8M | trimmed -1.7% | 2019 Q4 |
| Yacktman Asset Management | 4.09M | 3.60% | $121.7M | added +4.3% | 2023 Q2 |
| Goldman Sachs | 2.84M | 2.49% | $84.3M | added +534.3% | ≤2013 |
| Geode Capital | 2.11M | 1.86% | $62.8M | added +4% | ≤2013 |
| Semper Augustus Investments Group LLC (focused) | 2.03M | 1.78% | $60.4M | added +4.4% | 2019 Q3 |
| Bank OF America CORP /DE/ | 1.77M | 1.56% | $52.8M | trimmed -1.1% | ≤2013 |
| Morgan Stanley | 1.65M | 1.45% | $49.1M | trimmed -9.3% | ≤2013 |
| Citadel Advisors | 1.64M | 1.44% | $48.8M | added +98.3% | ≤2013 |
| Charles Schwab Investment Management | 1.56M | 1.37% | $46.3M | added +4.5% | ≤2013 |
| UBS | 1.42M | 1.25% | $42.3M | added +1.5% | ≤2013 |
| BNY Mellon | 1.23M | 1.08% | $36.7M | added +1% | ≤2013 |
| Two Sigma | 1.20M | 1.05% | $35.6M | opened | 2022 Q4 |
| AQR Capital | 1.17M | 1.02% | $34.7M | added +89.2% | 2020 Q3 |
| Millennium Management | 1.07M | 0.94% | $31.7M | added +2933% | ≤2013 |
| Northern Trust | 989.3k | 0.87% | $29.4M | added +2.8% | ≤2013 |
| Invesco | 796.0k | 0.70% | $23.7M | trimmed -1.1% | ≤2013 |
| Gotham Asset Management | 791.1k | 0.69% | $23.5M | added +138.2% | 2021 Q2 |
| Victory Capital Management INC | 782.2k | 0.69% | $23.3M | trimmed -3.6% | 2019 Q3 |
| Raymond James Financial INC | 721.8k | 0.63% | $21.5M | added +322.4% | ≤2013 |
| FMR (Fidelity) | 719.7k | 0.63% | $21.4M | trimmed -14.4% | 2015 Q1 |
| First Trust Advisors LP | 713.0k | 0.63% | $21.2M | added +80.8% | ≤2013 |
| Amundi | 684.0k | 0.60% | $20.3M | added +337.2% | 2025 Q1 |
| Bridgeway Capital Management, LLC | 664.8k | 0.58% | $19.8M | opened | 2026 Q1 |
| Tudor Investment | 660.5k | 0.58% | $19.6M | added +302.4% | 2025 Q4 |
| Wolf Hill Capital Management, LP (focused) | 633.5k | 0.56% | $18.8M | opened | 2026 Q1 |
| MetLife Investment Management, LLC | 627.6k | 0.55% | $18.7M | added +1025.2% | 2017 Q4 |
| Merewether Investment Management, LP | 623.4k | 0.55% | $18.5M | opened | 2026 Q1 |
| Nuveen | 576.9k | 0.51% | $17.2M | added +258% | ≤2013 |
| D. E. Shaw | 574.0k | 0.50% | $17.1M | added +151% | 2025 Q4 |
| PDT Partners | 507.4k | 0.45% | $15.1M | opened | 2025 Q3 |
| Klcm Advisors, INC. | 473.1k | 0.42% | $14.1M | added +1.3% | 2025 Q3 |
| Allianz Asset Management GmbH | 470.9k | 0.41% | $14.0M | added +39.2% | 2024 Q2 |
| Retirement Systems of Alabama | 452.6k | 0.40% | $13.5M | added +230.4% | ≤2013 |
| Grizzlyrock Capital, LLC (focused) | 445.1k | 0.39% | $13.2M | added +164.9% | 2025 Q3 |
| Connor, Clark & Lunn Investment Management LTD. | 435.8k | 0.38% | $13.0M | trimmed -12.8% | 2024 Q4 |
| Empowered Funds, LLC | 435.6k | 0.38% | $13.0M | added +1946% | 2021 Q2 |
| Citigroup INC | 407.2k | 0.36% | $12.1M | added +122.3% | ≤2013 |
| Quantinno Capital Management LP | 405.8k | 0.36% | $12.1M | trimmed -2.2% | 2021 Q4 |
| Mackenzie Financial CORP | 396.2k | 0.35% | $11.8M | opened | 2026 Q1 |
| SG Americas Securities, LLC | 353.9k | 0.31% | $10.5M | trimmed -22.3% | ≤2013 |
| Readystate Asset Management LP | 350.8k | 0.31% | $10.4M | opened | 2026 Q1 |
| Susquehanna Portfolio Strategies, LLC | 328.9k | 0.29% | $9.8M | added +6.2% | 2025 Q4 |
| American Century Companies INC | 318.1k | 0.28% | $9.5M | added +0.8% | 2020 Q4 |
| Jane Street | 313.9k | 0.28% | $9.3M | trimmed -3.9% | 2016 Q4 |
Largest 50 of 400 shown; the full ranked, searchable register is at boothcheck.com/holders/OLN. Related filers are grouped using the filings' own included-manager declarations. Historically, several managers opening new positions in the same quarter said almost nothing about the quarter that followed (59,118 cases since 2013). A filed record, not a forecast. Nothing here is investment advice.