Ironwood PharmaceuticalsIRWD
13F holders, Q1 2026 (March 31)227holders +28
49new positions
24sold out
6famous investors
$3.51avg. 13F price*
At the end of Q1 2026, 227 institutions reported holding Ironwood Pharmaceuticals Inc. (IRWD) in their 13F filings, up 28 from Q4 2025. 49 opened new positions and 24 sold out. The largest holders were Armistice Capital, LLC ($52.7M), BlackRock, Inc. ($46.9M) and Sarissa Capital Management LP ($32.3M). 6 famous investors held it, including Jim Simons / Peter Brown (0.0% of Renaissance Technologies's portfolio), Cliff Asness (0.0% of AQR Capital Management's portfolio) and Israel Englander (0.0% of Millennium Management's portfolio).
- Company
- Ironwood Pharmaceuticals Inc.
- CUSIP
- 46333X108
- Latest filing quarter
- Q2 2026
History
Number of 13F holders
Total Exit/New Position Q4 2025 → Q1 2026
| Institutions | Total Value | |
|---|---|---|
| New Positions | 49 | $18.3M |
| Exits | 24 | $6.9M |
All 13F filers, Q4 2025 → Q1 2026: 29,924,444 shares bought and 18,354,208 shares sold, net +11,570,236 shares. Counts holders who added, trimmed, opened or closed a position; split-adjusted.
Ownership 227 holders
| Armistice Capital, LLC | 1.74% | Reduce -6.2% | 15,028,000 | $52.7M |
| BlackRock, Inc. | 0.00% | Add +4.5% | 13,362,930 | $46.9M |
| Sarissa Capital Management LP | 20.46% | Reduce -42.3% | 9,188,635 | $32.3M |
| Bank of America Corp. | 0.00% | Reduce -24.6% | 8,682,907 | $30.5M |
| Renaissance Technologies | 0.04% | Reduce -1.8% | 8,061,073 | $28.3M |
| AQR Capital Management | 0.01% | Add +59.5% | 7,535,080 | $26.4M |
| State Street Corp. | 0.00% | Add +69.0% | 7,456,944 | $26.2M |
| Vanguard Portfolio Management LLC | 0.00% | — | 6,682,037 | $23.5M |
| Acadian Asset Management LLC | 0.03% | Add +1.9% | 6,577,272 | $23.1M |
| Vanguard Capital Management LLC | 0.00% | — | 6,097,454 | $21.4M |
| Two Sigma Investments, LP | 0.02% | Add +105.0% | 5,848,276 | $20.5M |
| Charles Schwab Investment Management Inc. | 0.00% | Reduce -4.8% | 4,737,857 | $16.6M |
| Geode Capital Management, LLC | 0.00% | Add +25.4% | 4,543,522 | $16.0M |
| Marshall Wace, LLP | 0.02% | Add +2.3% | 4,525,064 | $15.9M |
| Jacobs Levy Equity Management, Inc. | 0.05% | Add +31.6% | 3,632,477 | $12.7M |
| Arrowstreet Capital, Limited Partnership | 0.01% | Add +724.5% | 3,397,242 | $11.9M |
| Federated Hermes, Inc. | 0.02% | Add +0.9% | 3,348,806 | $11.8M |
| Goldman Sachs Group Inc. | 0.00% | Add +111.0% | 2,690,634 | $9.4M |
| Dimensional Fund Advisors LP | 0.00% | Add +529.3% | 2,082,055 | $7.3M |
| Connor, Clark & Lunn Investment Management Ltd. | 0.01% | Reduce -7.8% | 1,835,424 | $6.4M |
| Qube Research & Technologies Ltd | 0.01% | Reduce -5.4% | 1,590,081 | $5.6M |
| Susquehanna International Group, LLP | 0.01% | Add +228.0% | 1,472,157 | $5.2M |
| Northern Trust Corp. | 0.00% | Add +2.6% | 1,265,842 | $4.4M |
| Hillsdale Investment Management Inc. | 0.12% | Add +6.9% | 1,236,628 | $4.3M |
| Pacer Advisors, Inc. | 0.01% | New | 1,134,512 | $4.0M |
| Deutsche Bank AG | 0.00% | Add +1.4% | 1,124,989 | $3.9M |
| Vanguard Fiduciary Trust Co. | 0.00% | — | 988,630 | $3.5M |
| UBS Group AG | 0.00% | Add +82.8% | 933,225 | $3.3M |
| Morgan Stanley | 0.00% | Add +11.5% | 824,819 | $2.9M |
| FMR LLC | 0.00% | Add +15.1% | 790,386 | $2.8M |
| Raymond James Financial Inc. | 0.00% | Reduce -12.2% | 763,955 | $2.7M |
| Franklin Resources Inc. | 0.00% | Add +93.1% | 744,638 | $2.6M |
| Ieq Capital, LLC | 0.01% | Add +17.3% | 742,723 | $2.6M |
| Sei Investments Co. | 0.00% | Add +10.2% | 742,548 | $2.6M |
| Victory Capital Management Inc. | 0.00% | Add +3852.9% | 713,187 | $2.5M |
| Gsa Capital Partners LLP | 0.14% | Add +14.5% | 654,445 | $2.3M |
| Jane Street Group, LLC | 0.00% | Reduce -77.9% | 622,247 | $2.2M |
| State of Wisconsin Investment Board | 0.00% | Add +232.2% | 598,159 | $2.1M |
| Vanguard Global Advisers, LLC | 0.00% | — | 591,489 | $2.1M |
| Mackenzie Financial Corp. | 0.00% | Add +4751.3% | 560,034 | $2.0M |
| Integrated Quantitative Investments LLC | 0.35% | Add +437.8% | 552,104 | $1.9M |
| Invesco Ltd. | 0.00% | Add +21.9% | 547,360 | $1.9M |
| Man Group plc | 0.00% | Add +1034.9% | 540,864 | $1.9M |
| Wedge Capital Management L L P | 0.04% | New | 540,492 | $1.9M |
| Inspire Investing, LLC | 0.10% | New | 509,941 | $1.8M |
| Los Angeles Capital Management LLC | 0.01% | Reduce -19.7% | 509,247 | $1.8M |
| Bank of New York Mellon Corp | 0.00% | Reduce -5.1% | 484,036 | $1.7M |
| Millennium Management | 0.00% | Reduce -18.5% | 457,114 | $1.6M |
| Wellington Management Group LLP | 0.00% | Reduce -10.0% | 453,515 | $1.6M |
| Prudential Financial Inc. | 0.00% | Add +218.7% | 449,839 | $1.6M |
| Bridgeway Capital Management, LLC | 0.03% | Reduce -11.2% | 440,493 | $1.5M |
| Range Financial Group LLC | 0.51% | Add +1.7% | 433,256 | $1.5M |
| Amundi | 0.00% | Reduce -37.1% | 404,237 | $1.4M |
| BNP PARIBAS ASSET MANAGEMENT Holding S.A. | 0.00% | New | 375,288 | $1.3M |
| Cerity Partners LLC | 0.00% | Add +8.8% | 368,370 | $1.3M |
| CM Management, LLC | 1.03% | New | 350,000 | $1.2M |
| Robeco Institutional Asset Management B.V. | 0.00% | No change | 342,998 | $1.2M |
| LSV Asset Management | 0.00% | Add +3307.1% | 308,271 | $1.1M |
| Tidal Investments LLC | 0.00% | New | 304,475 | $1.1M |
| Lazard Asset Management LLC | 0.00% | Reduce -71.0% | 290,189 | $1.0M |
| Cwm, LLC | 0.00% | Add +19.4% | 278,217 | $977K |
| Segall Bryant & Hamill, LLC | 0.01% | New | 278,201 | $976K |
| Russell Investments Group, Ltd. | 0.00% | Reduce -1.3% | 261,789 | $915K |
| Globeflex Capital L P | 0.14% | New | 259,809 | $912K |
| Harvest Investment Services, LLC | 0.16% | Add +1099.2% | 241,881 | $849K |
| WINTON GROUP Ltd | 0.03% | Add +47.1% | 241,746 | $849K |
| Nuveen, LLC | 0.00% | Add +67.3% | 233,412 | $819K |
| OMERS ADMINISTRATION Corp | 0.01% | Add +5.2% | 226,310 | $794K |
| Walleye Capital LLC | 0.01% | Reduce -57.4% | 225,136 | $790K |
| Rafferty Asset Management, LLC | 0.00% | Add +234.1% | 216,623 | $760K |
| Wealth Enhancement Advisory Services, LLC | 0.00% | Add +45.8% | 226,688 | $741K |
| Mariner, LLC | 0.00% | Add +82.1% | 207,779 | $729K |
| Martingale Asset Management L P | 0.02% | New | 204,991 | $720K |
| Rhumbline Advisers | 0.00% | Reduce -3.5% | 192,934 | $677K |
| Hennion & Walsh Asset Management, Inc. | 0.02% | Reduce -5.9% | 184,485 | $648K |
| Vident Advisory, LLC | 0.01% | New | 184,337 | $647K |
| Creative Planning | 0.00% | Add +9.5% | 177,520 | $623K |
| KLP Kapitalforvaltning As | 0.00% | No change | 174,200 | $611K |
| Fifth Third Bancorp | 0.00% | New | 165,094 | $579K |
| Alliancebernstein L.P. | 0.00% | Reduce -16.9% | 165,790 | $559K |
| Legato Capital Management LLC | 0.05% | New | 156,059 | $548K |
| Voya Investment Management LLC | 0.00% | Add +407.0% | 145,819 | $512K |
| Canada Pension Plan Investment Board | 0.00% | Reduce -28.2% | 135,000 | $474K |
| Quantinno Capital Management LP | 0.00% | Add +9.1% | 129,703 | $455K |
| O'shaughnessy Asset Management, LLC | 0.00% | Reduce -55.8% | 128,243 | $450K |
| State of Wyoming | 0.05% | Reduce -18.5% | 128,175 | $450K |
| T. Rowe Price Associates Inc. | 0.00% | Add +25.1% | 124,314 | $437K |
| Citadel Advisors | 0.00% | Reduce -47.2% | 118,276 | $415K |
| Mercer Global Advisors Inc. | 0.00% | Add +49.5% | 115,080 | $404K |
| SG Americas Securities, LLC | 0.00% | Add +96.8% | 113,630 | $399K |
| JPMorgan Chase & Co. | 0.00% | Reduce -44.9% | 118,191 | $382K |
| Cercano Management LLC | 0.02% | No change | 101,378 | $356K |
| Ameriprise Financial Inc. | 0.00% | Reduce -17.2% | 99,341 | $349K |
| STRS Ohio | 0.00% | Add +27.1% | 97,400 | $342K |
| Profund Advisors LLC | 0.01% | Add +267.3% | 97,281 | $341K |
| Optimist Retirement Group LLC | 0.15% | Add +58.3% | 94,831 | $333K |
| Fuller & Thaler Asset Management, Inc. | 0.00% | New | 91,081 | $320K |
| Barclays PLC | 0.00% | Reduce -77.1% | 89,970 | $316K |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. | 0.00% | Add +15.4% | 90,109 | $312K |
| Allspring Global Investments Holdings, LLC | 0.00% | New | 79,193 | $309K |
"% of holder's portfolio" is IRWD's weight in each manager's 13F, not the share of Ironwood Pharmaceuticals Inc. the manager owns.