Mar 31, 2026 filings. Quarterly 13F reports arrive up to 45 days after quarter end; this register is filed through May 29, 2026.
374 institutional managers reported holding ALKS for the quarter ended Mar 31, 2026. Reported positions total over 95% of shares outstanding; the top 10 hold 58%. 67 opened new positions; 52 closed out. Complete ranked register from SEC 13F filings.
| manager | shares | % out | value (Mar 31, 2026 close) | change | held since |
|---|---|---|---|---|---|
| BlackRock | 28.31M | 17.04% | $1.00B | unchanged | ≤2013 |
| Vanguard Group | 18.34M | 11.04% | $648.9M | added +1.8% | ≤2013 |
| Baker Bros. Advisors LP | 10.01M | 6.02% | $354.2M | unchanged | 2024 Q2 |
| State Street | 9.47M | 5.70% | $334.9M | unchanged | ≤2013 |
| Renaissance Technologies | 6.16M | 3.71% | $218.0M | trimmed -7.6% | 2018 Q1 |
| American Century Companies INC | 6.07M | 3.65% | $214.8M | added +1.9% | 2021 Q3 |
| T. Rowe Price | 4.66M | 2.81% | $165.0M | trimmed -48.2% | ≤2013 |
| Dimensional Fund Advisors | 4.52M | 2.72% | $160.0M | added +2.5% | ≤2013 |
| Commodore Capital LP (focused) | 4.20M | 2.53% | $148.6M | added +18.3% | 2024 Q2 |
| Geode Capital | 4.18M | 2.52% | $148.0M | added +2.5% | ≤2013 |
| Deep Track Capital, LP | 3.59M | 2.16% | $127.0M | added +79.5% | 2025 Q4 |
| Wellington Management | 2.97M | 1.79% | $105.1M | trimmed -1.7% | ≤2013 |
| First Trust Advisors LP | 2.97M | 1.79% | $105.0M | added +104.2% | 2013 Q3 |
| PRIMECAP Management | 2.54M | 1.53% | $89.9M | trimmed -0.9% | 2016 Q2 |
| Nuveen | 2.46M | 1.48% | $87.1M | added +1.4% | ≤2013 |
| Holocene Advisors | 2.32M | 1.39% | $82.0M | opened | 2024 Q4 |
| Citadel Advisors | 2.24M | 1.35% | $79.3M | added +87.1% | 2018 Q1 |
| Charles Schwab Investment Management | 2.24M | 1.35% | $79.1M | added +3.9% | ≤2013 |
| BVF INC/IL (focused) | 2.00M | 1.20% | $70.8M | opened | 2026 Q1 |
| Soleus Capital Management, L.p. | 1.97M | 1.19% | $69.7M | added +49% | 2025 Q4 |
| Goldman Sachs | 1.88M | 1.13% | $66.6M | trimmed -17% | ≤2013 |
| Loomis Sayles & CO L P | 1.78M | 1.07% | $63.1M | trimmed -6.2% | 2023 Q1 |
| Morgan Stanley | 1.74M | 1.04% | $61.4M | trimmed -8.1% | ≤2013 |
| Northern Trust | 1.70M | 1.02% | $60.0M | added +2.6% | ≤2013 |
| RTW Investments, LP | 1.67M | 1.01% | $59.2M | unchanged | 2023 Q3 |
| Affinity Asset Advisors, LLC | 1.35M | 0.81% | $47.8M | added +35% | 2023 Q3 |
| FMR (Fidelity) | 1.32M | 0.80% | $46.8M | trimmed -2.3% | ≤2013 |
| Bank OF America CORP /DE/ | 1.21M | 0.73% | $42.8M | trimmed -9.2% | ≤2013 |
| Avoro Capital Advisors LLC (focused) | 1.20M | 0.72% | $42.5M | trimmed -14.3% | 2024 Q4 |
| Artisan Partners | 1.11M | 0.67% | $39.3M | trimmed -17.6% | 2020 Q1 |
| BNY Mellon | 1.04M | 0.62% | $36.7M | trimmed -3.5% | ≤2013 |
| Marshall Wace | 999.3k | 0.60% | $35.4M | added +669.3% | 2025 Q2 |
| Principal Financial Group INC | 958.0k | 0.58% | $33.9M | added +1.1% | ≤2013 |
| Pictet Asset Management Holding SA | 942.2k | 0.57% | $33.3M | trimmed -36.2% | 2018 Q3 |
| Panagora Asset Management INC | 932.9k | 0.56% | $33.0M | unchanged | ≤2013 |
| UBS | 898.2k | 0.54% | $31.8M | trimmed -69.4% | ≤2013 |
| T. Rowe Price Investment Management, INC. | 894.3k | 0.54% | $31.6M | added +42504.9% | 2025 Q4 |
| Driehaus Capital Management LLC | 792.0k | 0.48% | $28.0M | trimmed -0.6% | 2025 Q1 |
| Two Sigma | 780.7k | 0.47% | $27.6M | trimmed -35.7% | 2015 Q4 |
| BNP Paribas Financial Markets | 767.6k | 0.46% | $27.2M | added +14.3% | 2014 Q3 |
| Ameriprise Financial INC | 741.1k | 0.45% | $26.2M | added +39.5% | ≤2013 |
| D. E. Shaw | 710.3k | 0.43% | $25.1M | trimmed -22.1% | ≤2013 |
| Frazier Life Sciences Management, L.p. (focused) | 700.6k | 0.42% | $24.8M | unchanged | 2024 Q3 |
| Public Sector Pension Investment Board | 677.4k | 0.41% | $24.0M | added +0.9% | 2023 Q4 |
| Man Group | 625.0k | 0.38% | $22.1M | added +100% | 2018 Q1 |
| Bain Capital Life Sciences Investors, LLC (focused) | 610.0k | 0.37% | $21.6M | opened | 2026 Q1 |
| Segall Bryant & Hamill, LLC | 606.8k | 0.36% | $21.5M | trimmed -1.4% | 2020 Q1 |
| Balyasny Asset Management | 586.8k | 0.35% | $20.8M | trimmed -13.7% | 2025 Q4 |
| Woodline Partners LP | 558.6k | 0.34% | $19.8M | unchanged | 2023 Q3 |
| Invesco | 524.3k | 0.32% | $18.5M | trimmed -2.7% | ≤2013 |
Largest 50 of 374 shown; the full ranked, searchable register is at boothcheck.com/holders/ALKS. 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.