[Form 4] Cytokinetics Inc. Insider Trading Activity

Rhea-AI Filing Summary

Insider sale reported: Director Robert A. Harrington sold 2,150 shares of Cytokinetics, Inc. (CYTK) on 09/02/2025 at $48.67 per share, reducing his direct holdings to 20,493 shares. The Form 4 indicates the sale was reported under a transaction code for a sale and the filing was signed by an attorney-in-fact. The form also marks a box indicating the transaction may have been made pursuant to a written plan.

Positive

• Transaction appears to reference a written plan (10b5-1), indicating the sale may have been pre-scheduled rather than opportunistic
• Form 4 was properly executed and signed by an attorney-in-fact, meeting reporting formalities

Negative

• Director sold 2,150 shares, which reduced his direct holdings to 20,493 shares; insider sales can be interpreted negatively absent more context

Insights

Securities Analyst

TL;DR: A routine director sale of 2,150 CYTK shares was reported; likely non-material absent other context.

The filing documents a sale by a company director that reduced direct ownership to 20,493 shares. The reported price was $48.67 and the form indicates the transaction may have been executed under a written plan, which often signals pre-arranged trading rather than opportunistic insider selling. Without additional context on total outstanding shares or other insider activity, this single sale appears routine and not immediately material to valuation.

Corporate Governance Expert

TL;DR: Director sale documented and attested by attorney-in-fact; 10b5-1 plan indication reduces governance concerns.

The Form 4 shows appropriate reporting and a signature by an attorney-in-fact, meeting procedural requirements. The marked box suggesting a transaction pursuant to a written plan (10b5-1) reduces the likelihood the sale reflects undisclosed company-specific information. From a governance perspective, the filing follows disclosure norms for Section 16 insiders.

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).

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^*

Harrington Robert Arthur

(Last) (First) (Middle)

350 OYSTER POINT BLVD

(Street)

SOUTH SAN FRANCISCO CA 94080

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
CYTOKINETICS INC [ CYTK ]

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)
09/02/2025

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	09/02/2025		S		2,150	D	$48.67	20,493	D

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:

	/s/ John Faurescu, attorney-in-fact for Dr. Harrington	09/02/2025
	** 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 insider transaction was reported for CYTK?

Director Robert A. Harrington sold 2,150 shares of Cytokinetics (CYTK) on 09/02/2025 at $48.67 per share.

How many CYTK shares does the reporting person own after the sale?

The Form 4 states the reporting person beneficially owns 20,493 shares following the transaction.

Was the transaction indicated as part of a 10b5-1 plan?

Yes, the filing includes a checked box indicating the transaction was made pursuant to a contract, instruction, or written plan intended to satisfy the 10b5-1 affirmative defense.

Who signed the Form 4 for the reporting person?

The form was signed by John Faurescu, attorney-in-fact for Dr. Harrington on 09/02/2025.

Does the Form 4 show any derivative transactions?

No. Table II for derivative securities contains no reported transactions or holdings in this filing.