[Form 4] CALIFORNIA WATER SERVICE GROUP Insider Trading Activity

Rhea-AI Filing Summary

California Water Service Group executive Kenneth G. Jenkins, VP Water Resources Planning & Sustainability, reported routine share-withholding transactions related to restricted stock awards. On December 5, 2025, 38 shares of common stock were withheld at $44.88 per share to cover tax obligations from the vesting of a Restricted Stock (RSA) award granted on June 5, 2024, leaving him with 3,785 shares beneficially owned. On December 7, 2025, an additional 29 shares were withheld at $44.88 from the vesting of an RSA granted on March 7, 2023, after which he beneficially owned 3,756 shares. These transactions reflect tax withholding on equity compensation rather than open‑market buying or selling.

Insider Trade Summary

2 transactions reported

Mixed 2 txns

Insider Jenkins Kenneth G

Role VP Water Res Plan & Sustain

Type	Security	Shares	Price	Value
Tax Withholding	Common Stock	29	$44.88	$1K
Tax Withholding	Common Stock	38	$44.88	$2K

Holdings After Transaction: Common Stock — 3,756 shares (Direct)

Footnotes (1)

1. Represents the number of shares withheld and surrendered to the issuer to satisfy the tax withholding obligations that arose in connection with the vesting of Restricted Stock (RSA) Award granted on June 5, 2024. Represents the number of shares withheld and surrendered to the issuer to satisfy the tax withholding obligations that arose in connection with the vesting of Restricted Stock (RSA) Award granted on March 7, 2023.

Form 4 Insider Transactions: What Each Field Means →

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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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^*

Jenkins Kenneth G

(Last) (First) (Middle)

1720 NORTH FIRST STREET

(Street)

SAN JOSE CA 95112

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
CALIFORNIA WATER SERVICE GROUP [ CWT ]

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

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	VP Water Res Plan & Sustain

3. Date of Earliest Transaction (Month/Day/Year)
12/05/2025

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	12/05/2025		F		38(1)	D	$44.88	3,785	D
Common Stock	12/07/2025		F		29(2)	D	$44.88	3,756	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:

1. Represents the number of shares withheld and surrendered to the issuer to satisfy the tax withholding obligations that arose in connection with the vesting of Restricted Stock (RSA) Award granted on June 5, 2024.

2. Represents the number of shares withheld and surrendered to the issuer to satisfy the tax withholding obligations that arose in connection with the vesting of Restricted Stock (RSA) Award granted on March 7, 2023.

	By: /s/ Michelle R. Mortensen For: Kenneth G. Jenkins	12/09/2025
	** 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).
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