ARDX Form 4: Michael Raab sell-to-cover 45,687 shares; retains 1.5M+

Rhea-AI Filing Summary

Michael G. Raab, President & CEO and Director of Ardelyx, Inc. (ARDX), reported a sale of 45,687 shares of common stock on 08/21/2025 at a price of $5.9317 per share. The filing states the sale was an automatic sell-to-cover to satisfy tax withholding upon vesting of restricted stock units. After the transaction, Mr. Raab beneficially owns 1,502,250 shares directly, plus 24,364 shares held in his living trust and 1,000 shares held in trusts for his children. No derivative transactions are reported in this Form 4. The form is signed by an attorney-in-fact and dated 08/25/2025.

Positive

• Sale was disclosed as a sell-to-cover tied to RSU vesting, clarifying the reason for the transaction
• High retained insider ownership: 1,502,250 shares directly held plus family trust holdings, indicating continued alignment with shareholders

Negative

• None.

Insights

Securities Analyst

TL;DR: Routine sell-to-cover on RSU vesting; substantial insider ownership remains.

The reported transaction is a non-derivative sale of 45,687 shares executed solely to cover tax obligations arising from RSU vesting, a common and non-material liquidity event for executives. The filing shows continued concentrated insider ownership with 1,502,250 shares directly held by the reporting person plus additional family trust holdings, which maintains alignment with long-term shareholder interests. No options, warrants, or other derivative activity are disclosed.

Corporate Governance Expert

TL;DR: Disclosure is consistent with Section 16 requirements; transaction explained as tax withholding.

The Form 4 includes the required narrative explaining the sell-to-cover mechanism tied to RSU vesting, which supports transparency and compliance. The reporting person is both CEO and a director, and the filing delineates direct and indirect holdings including trusts for beneficiaries. The signature by an attorney-in-fact is documented, and no amendments or derivative positions are indicated, suggesting no apparent governance red flags within this filing.

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
Estimated average burden
hours per response:			0.5

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^*

RAAB MICHAEL

(Last) (First) (Middle)

C/O ARDELYX, INC.

400 FIFTH AVENUE, SUITE 210

(Street)

WALTHAM MA 02451

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
ARDELYX, INC. [ ARDX ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
08/21/2025

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
Common Stock	08/21/2025		S(1)		45,687	D	$5.9317	1,502,250	D
Common Stock								24,364	I	Family Trust(2)
Common Stock								1,000	I	Family Trust(3)

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. Pursuant to an automatic sell-to-cover imposed by the terms of the initial grant of the restricted stock units ("RSUs") awards, the shares were sold upon the vesting of the RSUs solely to cover applicable withholding taxes.

2. The shares are directly held by Michael G. Raab, Trustee of the Michael G. Raab Living Trust dated July 25, 2012.

3. The shares are owned directly by trusts for the benefit of the Reporting Person's children.

Remarks:

	/s/ Elizabeth Grammer, Attorney-in-Fact for Michael Raab	08/25/2025
	** 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 did ARDX insider Michael Raab report on Form 4?

He reported a sale of 45,687 common shares on 08/21/2025 at $5.9317 per share, disclosed as a sell-to-cover for RSU tax withholding.

How many ARDX shares does Michael Raab beneficially own after the reported transaction?

He beneficially owns 1,502,250 shares directly, plus 24,364 shares in his living trust and 1,000 shares in trusts for his children.

Was the Form 4 transaction related to options or other derivatives?

No. The Form 4 reports a non-derivative stock sale for tax withholding; no derivative securities are listed.

What position does the reporting person hold at Ardelyx (ARDX)?

The reporting person, Michael G. Raab, is listed as President & CEO and a Director of Ardelyx, Inc.

Who signed the Form 4 filing for Michael Raab and when?

The Form 4 bears the signature of Elizabeth Grammer, Attorney-in-Fact for Michael Raab and is dated 08/25/2025.