As of November 7, 2026, 4 holders' latest Schedule 13D or 13G filings report owning 5% or more of Ironwood Pharmaceuticals Inc. The largest reported stake is Armistice Capital, LLC's, at 8.43%. 15 filings are on record since July 7, 2025 (Schedule 13G/A, August 14, 2026).
Sell to companies like Ironwood Pharmaceuticals Inc? Enter your website and see 10 with a filed reason to buy from you this month. Free.
Opens in a new tab. No signup.
Key facts
- · Reporting person: Bank Of America Corp · Sole voting: 0 · Shared voting: 5,219,315 · Sole dispositive: 0 · Shared dispositive: 5,219,315 · SCHEDULE 13G/A, 2026-10-28
- · Reporting person: Armistice Capital, LLC · Sole voting: 0 · Shared voting: 13,932,000 · Sole dispositive: 0 · Shared dispositive: 13,932,000 · SCHEDULE 13G/A, 2026-08-14
- · Reporting person: State Street Corporation · Sole voting: 0 · Shared voting: 8,588,456 · Sole dispositive: 0 · Shared dispositive: 8,809,601 · SCHEDULE 13G, 2026-08-07
- · Reporting person: BlackRock, Inc. · Sole voting: 13,195,313 · Shared voting: 0 · Sole dispositive: 13,373,568 · Shared dispositive: 0 · SCHEDULE 13G/A, 2026-07-28
- · Holder: Armistice Capital, LLC · Percent: 9.22% · SCHEDULE 13G/A
Ironwood Pharmaceuticals Inc has 15 Schedule 13D or 13G filings on record since 2025-07-07. 4 holders' latest filing reports 5% or more of class a common stock. Each figure below is the holder's own, as filed, with the filing linked.
Holders
| Holder | Percent | Shares | Latest | Event date |
|---|---|---|---|---|
| Armistice Capital, LLC | 8.43% | 13,932,000 | SCHEDULE 13G/A, 2026-08-14 | 2026-06-30 |
| BlackRock, Inc. | 8.1% | 13,373,568 | SCHEDULE 13G/A, 2026-07-28 | 2026-06-30 |
| Sarissa Capital Management LP | 5.8% | 9,188,635 | SCHEDULE 13D/A, 2026-03-19 | 2026-03-17 |
| State Street Corporation | 5.4% | 8,809,601 | SCHEDULE 13G, 2026-08-07 | 2026-06-30 |
| Renaissance Technologies LLC | 4.9% | 8,061,073 | SCHEDULE 13G/A, 2026-05-14 | 2026-03-31 |
| Bank Of America Corp | 3.2% | 5,219,315 | SCHEDULE 13G/A, 2026-10-28 | 2026-09-30 |
| Barclays PLC | 1.95% | 3,167,713 | SCHEDULE 13G/A, 2025-11-12 | 2025-09-30 |
| The Vanguard Group | 0% | 0 | SCHEDULE 13G/A, 2026-03-27 | 2026-03-13 |
Holding shares or following this stake? See who's behind Ironwood Pharmaceuticals Inc and the warning signs.
Free to see. No signup.
Keep reading
More on Ironwood Pharmaceuticals Inc and the records around it.
Ironwood Pharmaceuticals Inc elsewhere on the record
- Leadership changes Jun 2026
- Who owns it
Companies that share a holder
- Renaissance Technologies LLC also filed stake reports on 46 other companies: AMERICAN PUBLIC EDUCATION INC (Aug 2026), Bolt Biotherapeutics, Inc. (Aug 2026), Commercial Vehicle Group, Inc. (Aug 2026)
- BANK OF AMERICA CORP /DE/ also filed stake reports on 74 other companies: BlackRock 2037 Municipal Target Term Trust (Nov 2026), TRIMAS CORP (Nov 2026), PIMCO CALIFORNIA MUNICIPAL INCOME FUND (Nov 2026)
- Barclays PLC also filed stake reports on 116 other companies: BIGLARI HOLDINGS INC-B (Nov 2026), CABLE ONE INC (Nov 2026), CALISA ACQUISITION CORP (Nov 2026)
Watch Ironwood Pharmaceuticals Inc
Get an email when Ironwood Pharmaceuticals Inc files again: a new raise, a leadership change, a layoff or an IPO filing. One email first to confirm; nothing else until you click it. At most one a day, one click to stop. Free for up to 3 companies.
Want the whole picture on Ironwood Pharmaceuticals Inc?
Example from a real report (our sample on Target): “Target eliminated approximately 1,800 corporate positions, with around 1,000 employees receiving layoff notices and the remainder accounted for by eliminating open roles.” Source: NBC News
A Full Report on Ironwood Pharmaceuticals Inc: verified, sourced, every claim cited, ready in a few minutes. See pricing.
What the Full Report on Ironwood Pharmaceuticals Inc covers
The Short Answer
Which Company This Is
What They Do, And How The Money Works
Who Runs It, And How To Reach Them
The Money: Funding, Valuation, Runway
Who Pays Them, And Who They Are Up Against
Warning Bells
Sources
17 cited sources found
Plus the sections for what you are deciding, which you pick after ordering.
A real finished report, first screen. Opens in a new tab.
Not ready to order yet? Keep this snapshot.
Sends this preview to you once; we won't add you to any list
Voting and dispositive power, as filed
| Reporting person | Sole voting | Shared voting | Sole dispositive | Shared dispositive | Filing |
|---|---|---|---|---|---|
| Armistice Capital, LLC | 0 | 13,932,000 | 0 | 13,932,000 | SCHEDULE 13G/A, 2026-08-14 |
| Steven Boyd | 0 | 13,932,000 | 0 | 13,932,000 | SCHEDULE 13G/A, 2026-08-14 |
| BlackRock, Inc. | 13,195,313 | 0 | 13,373,568 | 0 | SCHEDULE 13G/A, 2026-07-28 |
| State Street Corporation | 0 | 8,588,456 | 0 | 8,809,601 | SCHEDULE 13G, 2026-08-07 |
| Bank Of America Corp | 0 | 5,219,315 | 0 | 5,219,315 | SCHEDULE 13G/A, 2026-10-28 |
The latest filing identifies Ironwood Pharmaceuticals Inc by CUSIP 46333X108 and gives its principal executive office as 100 SUMMER STREET, SUITE 2300, BOSTON, MA 02110 (SCHEDULE 13G/A, 2026-10-28).
Timeline
| Filed | Holder | Percent | Filing |
|---|---|---|---|
| 2025-07-07 | The Vanguard Group | 10.01% | SCHEDULE 13G/A |
| 2025-08-12 | Barclays PLC | 6.88% | SCHEDULE 13G |
| 2025-08-15 | Armistice Capital, LLC | 9.94% | SCHEDULE 13G/A |
| 2025-11-12 | Barclays PLC | 1.95% | SCHEDULE 13G/A |
| 2025-11-14 | Bank Of America Corp | 7.4% | SCHEDULE 13G |
| 2026-02-17 | Armistice Capital, LLC | 9.85% | SCHEDULE 13G/A |
| 2026-03-19 | Sarissa Capital Management LP | 5.8% | SCHEDULE 13D/A |
| 2026-03-27 | The Vanguard Group | 0% | SCHEDULE 13G/A |
| 2026-04-27 | Bank Of America Corp | 6.1% | SCHEDULE 13G/A |
| 2026-05-14 | Renaissance Technologies LLC | 4.9% | SCHEDULE 13G/A |
| 2026-05-15 | Armistice Capital, LLC | 9.22% | SCHEDULE 13G/A |
| 2026-07-28 | BlackRock, Inc. | 8.1% | SCHEDULE 13G/A |
| 2026-08-07 | State Street Corporation | 5.4% | SCHEDULE 13G |
| 2026-08-14 | Armistice Capital, LLC | 8.43% | SCHEDULE 13G/A |
| 2026-10-28 | Bank Of America Corp | 3.2% | SCHEDULE 13G/A |
Questions about who owns Ironwood Pharmaceuticals Inc
Who owns Ironwood Pharmaceuticals Inc?
On this page, 4 holders' latest ownership filings report 5% or more of Ironwood Pharmaceuticals Inc: Armistice Capital, LLC (8.43%, Schedule 13G/A, filed 2026-08-14), BlackRock, Inc. (8.1%, Schedule 13G/A, filed 2026-07-28), Sarissa Capital Management LP (5.8%, Schedule 13D/A, filed 2026-03-19) and State Street Corporation (5.4%, Schedule 13G, filed 2026-08-07).
Who are the largest shareholders of Ironwood Pharmaceuticals Inc?
By the share each holder's latest filing reports, the largest holders of Ironwood Pharmaceuticals Inc on this page are Armistice Capital, LLC (8.43%), BlackRock, Inc. (8.1%) and Sarissa Capital Management LP (5.8%).
When did Armistice Capital, LLC buy into Ironwood Pharmaceuticals Inc?
The filings give report dates, not purchase dates. The earliest filing from Armistice Capital, LLC on this page is the Schedule 13G/A, filed 2025-08-15, reporting 9.94%; its latest, Schedule 13G/A filed 2026-08-14, reports 8.43%. That earliest filing is itself an amendment, which updates an earlier report.
Is this an audit or a full list?
Neither. The ownership list on this page covers only Schedule 13D and 13G filings, which holders make once they own 5% or more of a class of shares (an amendment can report a stake that has since fallen below 5%); 15 such filings are shown here. It is not an audit and not a full cap table: holders who never reached 5% are not listed, and a stake can change after its latest filing.
Also on the record for Ironwood Pharmaceuticals Inc
| Date | Record | Figure | Our page | Source |
|---|---|---|---|---|
| October 16, 2026 | Leadership change: Tammi Gaskins appointed, Chief Executive Officer, and 2 more | — | Leadership changes | Source |
| May 13, 2026 | Leadership change: Gregory Martini departs, Chief Financial Officer | — | Leadership changes | Source |
Tools for this story
Each opens in a new tab, filled in for Ironwood Pharmaceuticals Inc. With no account yet, you sign up free and land on the result.
Where this comes from
Anyone who comes to own more than 5% of a class of a listed company's voting shares has to tell the SEC. A holder who may seek to change or influence the company files Schedule 13D, and has to say in Item 4, "Purpose of Transaction", what it intends to do. A holder with no such intent, such as many index and passive funds, may file the shorter Schedule 13G. Both are amended when the stake changes, including when it falls below 5%.
Every row here is one of those filings, linked to the filing itself. Percentages and share counts are exactly as the holder filed them, for the holder the filing names; an amendment showing a lower figure is shown as filed. Item 4 text is quoted word for word. Where a 13D's Item 4 contains a sentence stating a definite intent to influence the company, that sentence is marked and quoted; the page does not describe the holder or its motives beyond the words it filed. Nothing here is investment advice.