Ardelyx (ARDX) CEO exercises options, sells 41,666 shares under plan

Rhea-AI Filing Summary

ARDELYX, INC. President & CEO Michael Raab exercised stock options to acquire 20,833 shares of common stock at $0.99 per share, then sold 41,666 shares at a weighted average price of $5.84 per share under a pre-arranged Rule 10b5-1 trading plan.

After these transactions, he held 1,816,448 common shares directly and 374,168 stock options of this award, plus indirect holdings of 24,364 and 1,000 shares through family trusts for his children.

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

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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).

X

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 MASSACHUSETTS 02451

(City) (State) (Zip)

UNITED STATES

(Country)

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

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
03/16/2026

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

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

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

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	03/16/2026		M(1)		20,833	A	$0.99	1,856,986	D
Common Stock	03/16/2026		S(1)		41,666	D	$5.84(2)	1,816,448(3)	D
Common Stock								24,364	I	Family Trust(4)
Common Stock								1,000	I	Family Trust(5)

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
Stock Option (Right to Buy)	$0.99	03/16/2026		M(1)			20,833	(6)	01/06/2032	Common Stock	20,833	$0	374,168	D

Explanation of Responses:

1. Transaction made pursuant to a 10b5-1 trading plan adopted by the Reporting Person on November 7, 2025.

2. Transaction was executed in multiple trades in prices ranging from $5.79 to $5.92, inclusive. The price reported in Column 4 above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote.

3. Includes 1,128 shares acquired under the Issuer's employee stock purchase plan on February 27, 2026.

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

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

6. The option becomes exercisable as it vests and the shares subject to the option vest in 48 successive, equal monthly installments on each monthly anniversary of January 6, 2022, subject to the Reporting Person's continued employment or service relationship with the Issuer on each such vesting date.

Remarks:

	/s/ Elizabeth Grammer, Attorney-in-Fact for Michael Raab	03/18/2026
	** 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.
* Form 4: SEC 1474 (03-26)

FAQ

What insider transactions did Ardelyx (ARDX) CEO Michael Raab report?

Michael Raab reported exercising options for 20,833 Ardelyx shares at $0.99 each and selling 41,666 common shares at a weighted average price of $5.84 per share. The sale and exercise both occurred on March 16, 2026.

Was the Ardelyx (ARDX) CEO’s stock sale part of a 10b5-1 trading plan?

Yes. The 41,666-share sale by Ardelyx CEO Michael Raab was made under a Rule 10b5-1 trading plan adopted on November 7, 2025. Such plans pre-schedule trades, making the timing more routine rather than a discretionary market-timing decision.

At what prices did Ardelyx (ARDX) CEO Michael Raab sell his shares?

Michael Raab sold 41,666 Ardelyx common shares at a weighted average price of $5.84 per share. Individual trades occurred in a price range from $5.79 to $5.92, according to the detailed price range disclosure provided.

How many Ardelyx (ARDX) shares does the CEO hold after these transactions?

Following the reported transactions, Michael Raab directly held 1,816,448 Ardelyx common shares. He also had indirect holdings of 24,364 and 1,000 shares through family trusts for his children, providing additional exposure beyond his direct personal position.

What happened to Ardelyx (ARDX) stock options held by the CEO in this Form 4?

Michael Raab exercised stock options covering 20,833 Ardelyx shares at an exercise price of $0.99 per share. After this exercise, 374,168 stock options of this award remained outstanding, according to the post-transaction derivative holdings disclosure.

Did Ardelyx (ARDX) CEO acquire any shares through employee plans before this filing?

Yes. The filing notes that Raab’s holdings include 1,128 Ardelyx shares acquired under the company’s employee stock purchase plan on February 27, 2026. These shares form part of his total direct ownership position disclosed after the transactions.