IRONWOOD PHARMACEUTICALS INC (IRWD) Top Institutional Shareholders
IRONWOOD PHARMACEUTICALS INC (IRWD) is currently reported in institutional portfolios tracked by InsiderSet based on the latest available SEC Form 13F filings for the quarter ended March 31, 2026. The institutional investors covered on this page collectively reported approximately $533.16M in IRWD holdings during the latest filing period.
Armistice Capital, Llc is currently the largest disclosed institutional shareholder of IRWD tracked by InsiderSet, reporting ownership valued at approximately $52.75M in its March 31, 2026 SEC Form 13F filing. Based on current market prices and the latest disclosed share count, the position is now estimated to be worth approximately $52.90M, representing an estimated gain of +0.28% since the filing period.
The top 10 institutional shareholders tracked on this page collectively account for approximately 58% of the total disclosed IRWD value among the investors covered in this analysis. Major shareholders include Armistice Capital, Llc, Blackrock, Inc., Sarissa Capital Management Lp, and several other long-term asset managers with concentrated positions in IRONWOOD PHARMACEUTICALS INC (IRWD).
This page ranks the largest institutional IRWD shareholders using publicly disclosed SEC Form 13F data, including reported values, estimated current holding values, portfolio allocation percentages, ownership concentration metrics, and historical holding changes across major hedge funds and investment firms.
Institutional Holders
219
Total Reported Value
$533.16M
Largest Holder
Armistice Capital, Llc
Largest Position
$52.75M
Insider Transactions (90d)
0
Latest Filing Quarter
Q1 2026
New Institutional Positions
157
Funds Exiting Positions
0
| Name | Investor/Manager | Portfolio % | Quantity | Reported Balance | Current Estimated Value | Gain/loss Since Filing | Estimated Portfolio Performance |
|---|---|---|---|---|---|---|---|
| Armistice Capital, Llc | 1.74% | 15,028,000 | $52,748,280 | $52,898,560 | +$150,280 | +0.28% | |
| Blackrock, Inc. | 0.00% | 13,362,930 | $46,903,884 | $47,037,514 | +$133,630 | +0.28% | |
| Sarissa Capital Management Lp | 20.46% | 9,188,635 | $32,252,109 | $32,343,995 | +$91,886 | +0.28% | |
| Bank Of America Corp | 0.00% | 8,682,907 | $30,477,004 | $30,563,833 | +$86,829 | +0.28% | |
| Renaissance Technologies LLC | Jim Simons | 0.04% | 8,061,073 | $28,294,366 | $28,374,977 | +$80,611 | +0.28% |
| Aqr Capital Management Llc | 0.01% | 7,535,080 | $26,448,131 | $26,523,482 | +$75,351 | +0.28% | |
| State Street Corp | 0.00% | 7,456,944 | $26,173,873 | $26,248,443 | +$74,570 | +0.28% | |
| Vanguard Portfolio Management Llc | 0.00% | 6,682,037 | $23,453,950 | $23,520,770 | +$66,820 | +0.28% | |
| Vanguard Capital Management Llc | 0.00% | 6,097,454 | $21,402,064 | $21,463,038 | +$60,974 | +0.28% | |
| Two Sigma Investments, Lp | 0.02% | 5,848,276 | $20,527,449 | $20,585,932 | +$58,483 | +0.28% | |
| Charles Schwab Investment Management Inc | 0.00% | 4,737,857 | $16,629,878 | $16,677,257 | +$47,379 | +0.28% | |
| Geode Capital Management, Llc | 0.00% | 4,543,522 | $15,950,694 | $15,993,197 | +$42,503 | +0.27% | |
| Marshall Wace, Llp | 0.02% | 4,525,064 | $15,882,975 | $15,928,225 | +$45,250 | +0.28% | |
| Jacobs Levy Equity Management, Inc | 0.05% | 3,632,477 | $12,749,994 | $12,786,319 | +$36,325 | +0.28% | |
| Arrowstreet Capital, Limited Partnership | 0.01% | 3,397,242 | $11,924,319 | $11,958,292 | +$33,973 | +0.28% | |
| Federated Hermes, Inc. | 0.02% | 3,348,806 | $11,754,309 | $11,787,797 | +$33,488 | +0.28% | |
| Goldman Sachs Group Inc | 0.00% | 2,690,634 | $9,444,125 | $9,471,032 | +$26,907 | +0.28% | |
| Dimensional Fund Advisors Lp | 0.00% | 2,082,055 | $7,306,566 | $7,328,834 | +$22,268 | +0.30% | |
| Connor, Clark & Lunn Investment Management Ltd. | 0.01% | 1,835,424 | $6,442,338 | $6,460,692 | +$18,354 | +0.28% | |
| Qube Research & Technologies Ltd | 0.01% | 1,590,081 | $5,581,184 | $5,597,085 | +$15,901 | +0.28% | |
| Susquehanna International Group, Llp | 0.01% | 1,472,157 | $5,167,271 | $5,181,993 | +$14,722 | +0.28% | |
| Northern Trust Corp | 0.00% | 1,265,842 | $4,443,105 | $4,455,764 | +$12,659 | +0.28% | |
| Hillsdale Investment Management Inc. | 0.12% | 1,236,628 | $4,340,565 | $4,352,931 | +$12,366 | +0.28% | |
| Deutsche Bank Ag\ | 0.00% | 1,124,989 | $3,948,711 | $3,959,961 | +$11,250 | +0.28% | |
| Vanguard Fiduciary Trust Co | 0.00% | 988,630 | $3,470,091 | $3,479,978 | +$9,887 | +0.28% | |
| Ubs Group Ag | 0.00% | 933,225 | $3,275,620 | $3,284,952 | +$9,332 | +0.28% | |
| Morgan Stanley | 0.00% | 824,819 | $2,895,115 | $2,903,363 | +$8,248 | +0.28% | |
| Fmr Llc | 0.00% | 790,386 | $2,774,254 | $2,782,159 | +$7,905 | +0.28% | |
| Raymond James Financial Inc | 0.00% | 763,955 | $2,681,482 | $2,689,122 | +$7,640 | +0.28% | |
| Franklin Resources Inc | 0.00% | 744,638 | $2,613,680 | $2,621,126 | +$7,446 | +0.28% | |
| Ieq Capital, Llc | 0.01% | 742,723 | $2,606,958 | $2,614,385 | +$7,427 | +0.28% | |
| Sei Investments Co | 0.00% | 742,548 | $2,606,340 | $2,613,769 | +$7,429 | +0.29% | |
| Victory Capital Management Inc | 0.00% | 713,187 | $2,503,286 | $2,510,418 | +$7,132 | +0.28% | |
| Jane Street Group, Llc | 0.00% | 622,247 | $2,184,086 | $2,190,309 | +$6,223 | +0.28% | |
| State Of Wisconsin Investment Board | 0.00% | 598,159 | $2,099,538 | $2,105,520 | +$5,982 | +0.28% | |
| Vanguard Global Advisers, Llc | 0.00% | 591,489 | $2,076,126 | $2,082,041 | +$5,915 | +0.28% | |
| Mackenzie Financial Corp | 0.00% | 560,034 | $1,965,719 | $1,971,320 | +$5,601 | +0.28% | |
| Integrated Quantitative Investments Llc | 0.35% | 552,104 | $1,937,885 | $1,943,406 | +$5,521 | +0.28% | |
| Invesco Ltd. | 0.00% | 547,360 | $1,921,234 | $1,926,707 | +$5,473 | +0.28% | |
| Man Group Plc | 0.00% | 540,864 | $1,898,433 | $1,903,841 | +$5,408 | +0.28% | |
| Wedge Capital Management L L P/Nc | 0.04% | 540,492 | $1,897,127 | $1,902,532 | +$5,405 | +0.28% | |
| Inspire Investing, Llc | 0.15% | 509,941 | $1,789,893 | $1,794,992 | +$5,099 | +0.28% | |
| Los Angeles Capital Management Llc | 0.01% | 509,247 | $1,787,457 | $1,792,549 | +$5,092 | +0.28% | |
| Bank Of New York Mellon Corp | 0.00% | 484,036 | $1,698,966 | $1,703,807 | +$4,841 | +0.28% | |
| Millennium Management Llc | 0.00% | 457,114 | $1,604,470 | $1,609,041 | +$4,571 | +0.28% | |
| Wellington Management Group Llp | 0.00% | 453,515 | $1,591,838 | $1,596,373 | +$4,535 | +0.28% | |
| Prudential Financial Inc | 0.00% | 449,839 | $1,578,935 | $1,583,433 | +$4,498 | +0.28% | |
| Bridgeway Capital Management, Llc | 0.03% | 440,493 | $1,546,130 | $1,550,535 | +$4,405 | +0.28% | |
| Range Financial Group Llc | 0.51% | 433,256 | $1,520,729 | $1,525,061 | +$4,332 | +0.28% | |
| Amundi | 0.00% | 404,237 | $1,418,872 | $1,422,914 | +$4,042 | +0.28% |
Frequently asked questions about IRWD
Who owns the most IRWD stock?
The largest holders of IRWD are typically major institutional investors such as asset managers and hedge funds reporting on Form 13F. The table above ranks tracked superinvestors by reported position size using the latest available filings for IRONWOOD PHARMACEUTICALS INC (IRWD).
Is IRWD widely held by superinvestors?
Many widely followed stocks like IRWD appear across numerous superinvestor portfolios because of liquidity, index inclusion, and fundamentals. The holder count and table above show how broadly IRWD is represented among the institutional managers we track.
What do “Current Estimated Value”, “Gain/loss Since Filing”, and “Estimated Portfolio Performance” mean?
Current Estimated Value is reported share quantity from the latest 13F times our most recent split-adjusted U.S. session close. Gain/loss Since Filing is that estimate minus the reported 13F dollar value; Estimated Portfolio Performance is that difference as a percent of the reported value. Green means the estimate is above the filing value; red means below (not purchase cost). If many filers share the same implied filing price per share, the performance % may match across rows. These are not official fund marks or live quotes.