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)

Dec 17, 2025

2. SEC Identification Number

0000091447

3. BIR Tax Identification No.

000190324000

4. Exact name of issuer as specified in its charter

SEMIRARA MINING AND POWER CORPORATION

5. Province, country or other jurisdiction of incorporation

Philippines

6. Industry Classification Code(SEC Use Only)

7. Address of principal office

2/F DMCI Plaza, 2281 Don Chino Roces Avenue, Makati City Postal Code 1231

8. Issuer's telephone number, including area code

632-88883000

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

-

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	4,250,547,620

11. Indicate the item numbers reported herein

5

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.

Semirara Mining and Power CorporationSCC

PSE Disclosure Form 4-26 - Legal Proceedings References: SRC Rule 17 (SEC Form 17-C) and
Section 4.4 of the Revised Disclosure Rules

Subject of the Disclosure
Petition for Certiorari filed by Commissioner of Internal Revenue
Background/Description of the Disclosure
Relative to Civil Case No. 25-011180 CV pending between Semirara Mining and Power Corporation (“SMPC”) versus the Department of Finance, Bureau of Internal Revenue, and Bureau of Customs before the RTC Makati, Branch 234 (“RTC”), we disclosed that we received today through external counsel, the Commissioner of Internal Revenue’s filed Petition for Certiorari and Prohibition under Rule 65 (with urgent prayer for issuance of Temporary Restraining Order and/or Writ of Preliminary Injunction) with the Court of Tax Appeals (“CTA”) against the RTC and SMPC seeking to annul and set aside the RTC’s Order and Resolution granting SMPC’s application for a writ of preliminary injunction and denying the BIR’s motion for reconsideration. The said petition also seeks to prohibit the RTC from continuing the trial of our case and to enjoin the RTC from enforcing its writ of preliminary injunction. To date, the CTA has taken no action on this Petition. In the hearing on December 16, 2025, the Commissioner of Internal Revenue filed a Motion to Suspend Proceedings with the RTC, praying for a suspension of the proceedings pending resolution of their Petition with the CTA. The RTC gave the SMPC and the BIR five days to file their respective comments and replies.

Name of the court or agency in which the proceedings are pending	Court of Tax Appeals
Date Instituted	Dec 12, 2025
Docket Number	SCA Case No. 0043 (Civil Case No. R-MKT-25-01180-CV)

Principal Parties
Commissioner of Internal Revenue (Petitioner) vs. Branch 234, RTC Makati and Semirara Mining and Power Corporation (Respondents)
Nature and description of the legal proceedings
Petition for Certiorari and Prohibition Under Rule 65 (with TRO and/or Writ of Preliminary Injunction
The effect(s) on the Issuer's business or operations, if any
No effect on the its business operations
Other Relevant Information
Update on the Legal Proceedings. Please see attached SEC Form 17-C.