[Form 4] California Water Service Insider Trading Activity

Rhea-AI Filing Summary

Michelle R. Mortensen, Vice President, Corporate Secretary and Chief of Staff of California Water Service Group (CWT), reported two non-derivative transactions in common stock related to tax-withholding on vested restricted stock awards. On 09/05/2025, 73 shares were withheld and surrendered at an indicated price of $47.09 to satisfy tax withholding from a Restricted Stock Award granted 06/05/2024. On 09/07/2025, 57 shares were withheld and surrendered at $47.09 to satisfy tax withholding from a Restricted Stock Award granted 03/07/2023. The Form 4 is signed 09/09/2025 and shows adjusted beneficial ownership levels following these withholdings.

Positive

• Compliance: Reporting person properly disclosed tax-withholding transactions, showing adherence to Section 16 filing requirements

Negative

• None.

Insights

Financial Analyst

TL;DR: Routine insider withholding to satisfy taxes on vested restricted stock; immaterial to company fundamentals.

The reported transactions are tax-withholding events tied to RSA vesting, not open-market sales or purchases. Total shares withheld (130 shares) are small relative to typical public-company float and do not change control or materially affect outstanding share count. From an investor perspective, this is a compliance reporting item rather than a signal of a change in insider conviction.

Corporate Governance Expert

TL;DR: Proper Section 16 reporting of withholding for vested awards; demonstrates routine compliance with equity compensation processes.

The Form 4 discloses that shares were surrendered to cover tax obligations from restricted stock vesting on two grant dates. The filing indicates internal governance and payroll processes functioning as expected. No additional derivative transactions, option exercises, or discretionary sales were reported. Documentation appears complete with signature dated 09/09/2025.

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^*

Mortensen Michelle R

(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 Corp Sect & Chief of Staff

3. Date of Earliest Transaction (Month/Day/Year)
09/05/2025

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	09/05/2025		F		73(1)	D	$47.09	12,622.8	D
Common Stock	09/07/2025		F		57(2)	D	$47.09	12,565.8	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.

	/s/ Michelle R. Mortensen	09/09/2025
	** 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).
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 transactions did Michelle R. Mortensen report on Form 4 for CWT?

She reported two non-derivative transactions where 73 shares (09/05/2025) and 57 shares (09/07/2025) were withheld and surrendered to satisfy tax withholding on vested restricted stock awards.

Were these transactions open-market sales for CWT (ticker CWT)?

No. The Form 4 shows the shares were withheld and surrendered to the issuer to satisfy tax withholding obligations from RSA vesting, not open-market sales.

Which restricted stock awards triggered the withholding reported in the CWT Form 4?

The 73 shares relate to an RSA granted on 06/05/2024 and the 57 shares relate to an RSA granted on 03/07/2023.

What price is shown on the Form 4 for the withheld shares?

The Form 4 lists a price of $47.09 for both withholding transactions.

When was the Form 4 signed and filed for these CWT transactions?

The Form 4 is signed by Michelle R. Mortensen on 09/09/2025.