Form: SCHEDULE 13G

Statement of Beneficial Ownership by Certain Investors

April 29, 2026






Check the appropriate box to designate the rule pursuant to which this Schedule is filed:
Checkbox checked   Rule 13d-1(b)
Checkbox not checked   Rule 13d-1(c)
Checkbox not checked   Rule 13d-1(d)




schemaVersion:


SCHEDULE 13G



1Names of Reporting Persons

Vanguard Portfolio Management
2Check the appropriate box if a member of a Group (see instructions)

Checkbox not checked  (a)
Checkbox not checked  (b)
3Sec Use Only
4Citizenship or Place of Organization

PENNSYLVANIA
Number of Shares Beneficially Owned by Each Reporting Person With:
9Aggregate Amount Beneficially Owned by Each Reporting Person

4,312,668.00
10Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

Checkbox not checked
11Percent of class represented by amount in row (9)

7.23 %
12Type of Reporting Person (See Instructions)

IA

Comment for Type of Reporting Person:   In accordance with SEC Release No. 34-39538 (January 12, 1998), this Schedule 13G reflects the securities beneficially owned, or deemed to be beneficially owned, by Vanguard Portfolio Management LLC and the following affiliates of Vanguard Portfolio Management LLC or business divisions of such affiliates: Vanguard Fiduciary Trust Company and Vanguard Global Advisers, LLC. This Schedule 13G includes securities held by Vanguard funds, or sleeves thereof, over which Vanguard Portfolio Management LLC exercises dispositive power, in addition to securities held by clients over which the affiliates or business divisions of such affiliates indicated above exercise dispositive and/or voting power. This Schedule 13G does not include securities, if any, beneficially owned by other subsidiaries or affiliates of Vanguard Portfolio Management LLC, or business divisions of such subsidiaries whose ownership of securities is disaggregated from that of the reporting business unit in accordance with such release.


SCHEDULE 13G

Item 1. 
(a)Name of issuer:

California Water Service Group
(b)Address of issuer's principal executive offices:

1720 North First Street, San Jose, CA, 95112
Item 2. 
(a)Name of person filing:

Vanguard Portfolio Management
(b)Address or principal business office or, if none, residence:

100 Vanguard Blvd,, Malvern, PA, 19355
(c)Citizenship:

PA
(d)Title of class of securities:

Common Stock
(e)CUSIP Number(s):

130788102
Item 3.If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)Checkbox not checked   Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)Checkbox not checked   Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)Checkbox not checked   Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)Checkbox not checked   Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)Checkbox checked   An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)Checkbox not checked   An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)Checkbox not checked   A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)Checkbox not checked   A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)Checkbox not checked   A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)Checkbox not checked   A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J),
       please specify the type of institution:
(k)Checkbox not checked   Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
 
Item 4.Ownership
(a)Amount beneficially owned:

4312668
(b)Percent of class:

7.23  %
(c)Number of shares as to which the person has:
 (i) Sole power to vote or to direct the vote:

22995

 (ii) Shared power to vote or to direct the vote:

0

 (iii) Sole power to dispose or to direct the disposition of:

4312668

 (iv) Shared power to dispose or to direct the disposition of:

0

Item 5.Ownership of 5 Percent or Less of a Class.
 
Not Applicable
Item 6.Ownership of more than 5 Percent on Behalf of Another Person.
 
If any other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, such securities, a statement to that effect should be included in response to this item and, if such interest relates to more than 5 percent of the class, such person should be identified. A listing of the shareholders of an investment company registered under the Investment Company Act of 1940 or the beneficiaries of employee benefit plan, pension fund or endowment fund is not required.


Vanguard Portfolio Management, including investment companies registered under the Investment Company Act of 1940 and other managed accounts, have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the securities reported herein.No one other person's interest in the securities reported herein is more than 5%.
Item 7.Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
 
Not Applicable
Item 8.Identification and Classification of Members of the Group.
 
Not Applicable
Item 9.Notice of Dissolution of Group.
 
Not Applicable

Item 10.Certifications:
 
By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under § 240.14a-11.

 
Vanguard Portfolio Management
 
Signature:Ashley Grim
Name/Title:Head of Global Fund Administration
Date:04/29/2026