SECURITIES AND EXCHANGE COMMISSIONSEC FORM 17-C

CURRENT REPORT UNDER SECTION 17
OF THE SECURITIES REGULATION CODE
AND SRC RULE 17.2(c) THEREUNDER

1. Date of Report (Date of earliest event reported)

Jan 6, 2026

2. SEC Identification Number

A1996-11593

3. BIR Tax Identification No.

005-038-428-000

4. Exact name of issuer as specified in its charter

Manila Water Company, Inc.

5. Province, country or other jurisdiction of incorporation

Quezon City, Philippines

6. Industry Classification Code(SEC Use Only)

7. Address of principal office

MWSS Administration Building, No. 489 Katipunan Road, Balara, Quezon City Postal Code 1105

8. Issuer's telephone number, including area code

09171547921

9. Former name or former address, if changed since last report

n/a

10. Securities registered pursuant to Sections 8 and 12 of the SRC or Sections 4 and 8 of the RSA

Title of Each Class	Number of Shares of Common Stock Outstanding and Amount of Debt Outstanding
Common	2,603,687,141
Preferred (Unlisted)	3,563,756,068

11. Indicate the item numbers reported herein

-

The Exchange does not warrant and holds no responsibility for the veracity of the facts and representations contained in all corporate disclosures, including financial reports. All data contained herein are prepared and submitted by the disclosing party to the Exchange, and are disseminated solely for purposes of information. Any questions on the data contained herein should be addressed directly to the Corporate Information Officer of the disclosing party.

Manila Water Company, Inc.MWC

PSE Disclosure Form 9-2 - Sale of Treasury Shares References: Section 9 of the Revised Disclosure Rules

Subject of the Disclosure
Vesting of Shares Under the Stock Incentive Plan (SIP)
Background/Description of the Disclosure
On January 6, 2026, the Office of the Corporate Secretary of Manila Water Company, Inc. (MWC) was informed that 2,187,869 common shares which were granted under the MWC Stock Incentive Plan have vested in Mr. Jose Victor Emmanuel A. de Dios’ favor pursuant to the SIP.

Type of Securities

• Common
• Preferredn/a
• Othersn/a

Details of Sale of Treasury Shares

Date of Transaction	Number of Shares Sold	Price Per Share
Jan 2, 2026	2,187,869	Grant under the Company

Effects on Number of Shares

	Before	After
Outstanding Shares	2,601,499,272	2,603,687,141
Treasury Shares	284,296,625	282,108,756

Cumulative Number of Shares Sold to Date 1	10,089,978
Number of Shares Authorized for Sale	282,108,756

Other Relevant Information
Please note that the transaction covered herein is not a sale of treasury shares but a grant and transfer of SIP shares sources from treasury shares to the grantee participant, pursuant to the SIP for employees, officers, and directors of MWC and its operating subsidiaries.

¹ From the date when the sale of treasury shares program commenced.