Sarissa funds trim Ironwood (NASDAQ: IRWD) stake with 6.7M-share sale

Rhea-AI Filing Summary

IRONWOOD PHARMACEUTICALS INC director-related entities reported major share sales alongside a small equity grant. Investment vehicles advised by Sarissa Capital Management LP sold a total of 6,730,800 shares of Class A Common Stock on March 17, 2026 in open-market transactions at prices between $3.05 and $3.31 per share, leaving 9,188,635 shares held indirectly. Separately, Dr. Alexander J. Denner received a grant of 4,451 shares on March 13, 2026 under the company’s non-employee director compensation policy, bringing his directly held shares to 256,309. Footnotes state Sarissa Capital and its funds directly hold the sold and remaining indirect shares, with each party, including Dr. Denner, disclaiming beneficial ownership beyond their pecuniary interest.

Insights

Equity ownership & governance analyst

Large fund-related stock sales dominate this filing, offset by a small director equity grant.

The disclosure shows entities advised by Sarissa Capital Management executed open-market sales of 6,730,800 shares of IRONWOOD PHARMACEUTICALS INC Class A Common Stock at prices around $3.05–$3.31. These are indirect holdings associated with director Alexander J. Denner, not his personal account.

After these trades, the Sarissa-advised vehicles still hold 9,188,635 shares indirectly, while Dr. Denner directly holds 256,309 shares following a 4,451-share award under the non-employee director compensation policy effective January 1, 2024. Footnotes emphasize that Sarissa Capital, the Sarissa Funds, and Dr. Denner each disclaim beneficial ownership beyond their pecuniary interests.

This pattern combines a sizable net reduction in fund-held shares with continued substantial exposure. The filing does not indicate any trading plan or broader strategic rationale, so the economic significance depends on the scale of Ironwood’s overall share base and future ownership disclosures.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

DENNER ALEXANDER J

(Last) (First) (Middle)

C/O IRONWOOD PHARMACEUTICALS, INC.

100 SUMMER STREET, SUITE 2300

(Street)

BOSTON MA 02110

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
IRONWOOD PHARMACEUTICALS INC [ IRWD ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
	Officer (give title below)		Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
03/13/2026

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Class A Common Stock	03/13/2026		A(1)		4,451	A	$0	256,309	D
Class A Common Stock	03/17/2026		S		6,725,000	D	$3.05	9,194,435	I	See footnote(2)
Class A Common Stock	03/17/2026		S		5,800	D	$3.31	9,188,635	I	See footnote(2)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. Issued pursuant to the Second Amended and Restated Non-employee Director Compensation Policy, effective January 1, 2024.

2. Consists of shares that are held by Sarissa Capital Management LP ("Sarissa Capital") or by the funds and other investment vehicles (the "Sarissa Funds") for which Sarissa Capital serves as investment advisor. Dr. Denner is the Chief Investment Officer of Sarissa Capital and the managing member, general partner or other control party of the Sarissa Funds. By virtue of the foregoing, Dr. Denner may be deemed to indirectly beneficially own the shares that these funds directly beneficially own. Each of SarissaCapital, the Sarissa Funds and Dr. Denner disclaims beneficial ownership of these shares except, in each case, to the extent of their pecuniary interest therein.

Remarks:

Exhibit 24 - Power of Attorney

	/s/ Alexander Denner	03/17/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What insider transactions did IRWD report for Alexander J. Denner and related entities?

IRONWOOD PHARMACEUTICALS INC reported that Sarissa-advised entities sold 6,730,800 shares of Class A Common Stock and that Alexander J. Denner received a 4,451-share equity award. The sales were open-market transactions, while the award came under the non-employee director compensation policy effective January 1, 2024.

How many IRWD shares did Sarissa-related funds sell and at what prices?

Sarissa Capital Management LP–advised funds sold 6,730,800 IRWD Class A Common Stock shares on March 17, 2026. The transactions occurred in open-market sales at prices of $3.05 and $3.31 per share, as disclosed in the Form 4 transaction detail and summary fields.

What are Alexander J. Denner’s direct IRWD holdings after these transactions?

After the reported transactions, Alexander J. Denner directly holds 256,309 IRWD Class A Common Stock shares. This includes a 4,451-share grant received on March 13, 2026 under Ironwood’s Second Amended and Restated Non-employee Director Compensation Policy, which became effective January 1, 2024.

How many IRWD shares do Sarissa-advised entities hold after the reported sales?

Following the March 17, 2026 open-market sales, entities advised by Sarissa Capital Management LP hold 9,188,635 IRWD Class A Common Stock shares indirectly. These holdings are attributed to Sarissa Capital and the Sarissa Funds, with each party, including Dr. Denner, disclaiming beneficial ownership beyond their pecuniary interest.

Are the IRWD share sales attributed directly to Alexander J. Denner personally?

The sales are attributed to Sarissa Capital Management LP and the Sarissa Funds, not Denner’s personal account. Footnotes explain he is Chief Investment Officer and a control party of the funds and may be deemed an indirect beneficial owner, while all parties disclaim ownership except to the extent of pecuniary interest.

What type of acquisition did Alexander J. Denner report for IRWD stock?

Denner reported an acquisition coded “A,” indicating a grant or award of 4,451 IRWD Class A Common Stock shares. The award was issued under Ironwood’s Second Amended and Restated Non-employee Director Compensation Policy for non-employee directors, effective January 1, 2024, and carries no purchase price.