Atlas owner discloses 4.53M-share stake in H2O America (HTO)

Rhea-AI Filing Summary

H2O America amendment reports that ATLAS Infrastructure Partners (UK) Ltd. (with GIP Atlas Holdings Limited as its sole owner) beneficially owns 4,532,084 shares of Common Stock, representing 10.83% of the class. The filing discloses shared voting and dispositive power over the 4,532,084 shares. The amendment is signed by Clinton Joyner, Partner and COO, dated 04/08/2026.

Insights

Investor Relations Analyst

Large passive holder reports a 10.83% stake via shared control.

The filing shows 4,532,084 shares beneficially owned by Atlas Infrastructure Partners (UK) Ltd., with shared voting and dispositive power rather than sole control. GIP Atlas Holdings Limited is disclosed as the sole owner of the reporting entity.

Holding size (10.83%) is disclosure-grade for institutional ownership; subsequent filings or transaction reports would show changes. Voting and disposition are shared; timing and intent beyond this ownership percentage are not stated in the excerpt.

Key Figures

Beneficial ownership: 4,532,084 shares Percent of class: 10.83% CUSIP: 784305104 +2 more

5 metrics

Beneficial ownership 4,532,084 shares Beneficially owned amount reported in Item 4

Percent of class 10.83% Percent of class reported in Item 4

CUSIP 784305104 Identifier shown in the header

Header date 03/04/2026 Date appearing in the header block

Signature date 04/08/2026 Filing signed by Clinton Joyner on this date

Key Terms

Schedule 13G/A, beneficially owned, shared dispositive power, shared voting power

4 terms

Schedule 13G/A regulatory

"Amendment No. 1 ) H2O America Common Stock"

A Schedule 13G/A is an amended public filing with the U.S. securities regulator that updates a previous Schedule 13G, disclosing when an individual or group holds a substantial (typically over 5%) stake in a company and is claiming a passive, non‑controlling intent. Investors monitor these updates because rising or falling holdings can signal changing confidence, potential future moves, or shifts in voting power — like watching a public ledger where large shareholders quietly adjust their positions.

beneficially owned financial

"Item 4. | Ownership (a) | Amount beneficially owned: 4,532,084"

Beneficially owned describes securities or assets where a person has the economic rights and control—such as the right to receive dividends and to direct voting—even if legal title is held in another name. Think of it like having the keys and using a car that’s registered to someone else: you get the benefits and make decisions. Investors care because beneficial ownership reveals who truly controls value and voting power, affecting corporate decisions and takeover dynamics.

shared dispositive power financial

"Shared power to dispose or to direct the disposition of: 4,532,084"

shared voting power financial

"Shared power to vote or to direct the vote: 4,532,084"

Shared voting power occurs when two or more parties jointly have the right to vote or decide how a block of company shares is cast, like co-owners who must agree before moving a piece of furniture. Investors care because who controls voting rights affects board elections, major corporate decisions and takeover outcomes, and shared control can alter regulatory disclosures and the practical influence any holder has over a company’s direction and value.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 1)

H2O America

(Name of Issuer)

Common Stock, par value $0.001 per share

(Title of Class of Securities)

784305104

(CUSIP Number)

03/04/2026

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

Rule 13d-1(b)

Rule 13d-1(c)

Rule 13d-1(d)

schemaVersion:

SCHEDULE 13G

CUSIP Number(s): 784305104

1

Names of Reporting Persons

ATLAS Infrastructure Partners (UK) Ltd.

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

UNITED KINGDOM

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 4,532,084.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 4,532,084.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

4,532,084.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

10.83 %

12

Type of Reporting Person (See Instructions)

IA

SCHEDULE 13G

CUSIP Number(s): 784305104

1

Names of Reporting Persons

GIP Atlas Holdings Limited

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

UNITED KINGDOM

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 4,532,084.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 4,532,084.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

4,532,084.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

10.83 %

12

Type of Reporting Person (See Instructions)

IA

Comment for Type of Reporting Person: GIP Atlas Holdings Limited is the sole owner of Atlas Infrastructure Partners (UK) Ltd, holding 100% of its equity interests; however, it does not exercise investment discretion with respect to the entity.

SCHEDULE 13G

Item 1.
(a)	Name of issuer: H2O America
(b)	Address of issuer's principal executive offices: 110 West Taylor Street, San Jose, CA, 95110
Item 2.
(a)	Name of person filing: ATLAS Infrastructure Partners (UK) Ltd. GIP Atlas Holdings Limited
(b)	Address or principal business office or, if none, residence: 1ST Floor West, 1-3 College Hill, London, EC4R 2RA
(c)	Citizenship: United Kingdom
(d)	Title of class of securities: Common Stock, par value $0.001 per share
(e)	CUSIP No.:
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)	Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)	Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)	Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)	Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)	An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)	An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)	A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)	A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)	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)	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)	Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.	Ownership
(a)	Amount beneficially owned: 4,532,084
(b)	Percent of class: 10.83 %
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: 0
	(ii) Shared power to vote or to direct the vote: 4,532,084
	(iii) Sole power to dispose or to direct the disposition of: 0
	(iv) Shared power to dispose or to direct the disposition of: 4,532,084
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.
	Not Applicable
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 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.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

ATLAS Infrastructure Partners (UK) Ltd.

Signature:	/s/ Clinton Joyner
Name/Title:	Partner and COO
Date:	04/08/2026

GIP Atlas Holdings Limited

Signature:	/s/ Clinton Joyner
Name/Title:	Partner and COO
Date:	04/08/2026

FAQ

What stake does ATLAS Infrastructure Partners report in H2O America (HTO)?

ATLAS Infrastructure Partners reports beneficial ownership of 4,532,084 shares, equal to 10.83% of H2O America's common stock. The filing lists shared voting and dispositive power over those 4,532,084 shares.

Who else is named in the Schedule 13G/A for HTO?

GIP Atlas Holdings Limited is named as the sole owner of Atlas Infrastructure Partners (UK) Ltd. The filing states GIP Atlas Holdings Limited does not exercise investment discretion for the entity, per the comment included.

What type of control is reported over the shares in the HTO filing?

The filing reports shared voting power and shared dispositive power for 4,532,084 shares. It reports 0 shares held with sole voting or sole dispositive power in the excerpt.

When was the H2O America Schedule 13G/A signed?

The amendment is signed by Clinton Joyner, Partner and COO, with signature dates shown as 04/08/2026. The cover shows a date of 03/04/2026 in the header context.