G.R. No. 149638 - Moncayo Integrated Small-Scale Miners Association, Inc. vs. Southeast Mindanao Gold Mining Corp.

The dispute centers on the Diwalwal Gold Rush area in Mt. Diwata, Mindanao—a site long embroiled in mining controversies since the mid‑1980s.
At issue is a 729‑hectare portion, which was excluded from respondent Southeast Mindanao Gold Mining Corporation’s (SMGMC) Mineral Production Sharing Agreement (MPSA) application and subsequently declared as a People’s Small‑Scale Mining Area.

Two petitions were filed for review: one by Moncayo Integrated Small‑Scale Miners Association, Inc. (MISSMA) and another by DENR Secretary Antonio H. Cerilles.
The matter was previously addressed before the Mines Adjudication Board (MAB), which in its January 6, 1998 decision vacated an earlier panel decision by dismissing adverse claims against SMGMC’s MPSA application based on DENR Administrative Order No. 66 (DAO No. 66).
The adverse claims, involving various small‑scale mining entities and individuals, were linked to the declaration of certain forestlands for small‑scale mining purposes.
Subsequent decisions by the Court of Appeals—first denying the petition in July 2000 and then, upon motions for reconsideration, amending its decision on August 27, 2001 by annulling the DENR Secretary’s decision for grave abuse of discretion—further complicated the issues.

Initially, Marcopper Mining Corporation was issued a prospecting permit and an exploration permit (EP 133) covering 4,941 hectares in the Agusan‑Davao‑Surigao Forest Reserve.
EP 133 was later transferred to SMGMC, which subsequently became the subject of adverse claims by several groups anchored on the 729‑hectare area designated for small‑scale mining.
The Provincial Mining Regulatory Board (PMRB) declared, after dismissing oppositions, the 729‑hectare area as a People’s Small‑Scale Mining Area through its March 30, 1999 decision.
DENR Secretary Cerilles modified the PMRB decision in his September 20, 1999 ruling by delineating the area into two blocks for different groups of miners, an action that raised questions regarding his statutory authority.

Additional petitions and motions raised issues such as forum shopping and litis pendencia, wherein similar issues appeared before multiple cases, notably G.R. No. 132475 pertaining to SMGMC’s MPSA.
Later, significant developments—including the issuance of Proclamation No. 297 by then President Macapagal‑Arroyo (declaring an area as a mineral reservation and environmentally critical area) and the Supreme Court’s June 23, 2006 decision in Apex Mining v. SMGMC—rendered the disputed matters moot.
There were further developments involving administrative orders, agreements with indigenous communities, and additional public bidding awards in adjoining areas that reinforced the practical mootness of the original issues.

Whether the Court of Appeals should have resolved substantive issues of forum shopping and litis pendencia by addressing the merits, given that identical parties and similar relief were involved in multiple related cases.

Whether the DENR Secretary’s decision to modify the PMRB’s declaration—specifically, his unilateral delineation of the 729‑hectare People’s Small‑Scale Mining Area into two blocks—exceeded his statutory authority and contravened the inherent mandate of the MAB decision and the objectives of Republic Act No. 7076.

Whether the administrative and judicial actions regarding the declaration and segmentation of the 729‑hectare area are valid in light of overlapping authorities among the PMRB, DENR Secretary, and the MAB.

Whether supervening events—including the issuance of Proclamation No. 297 and the apex decisions declaring EP 133 expired and DAO No. 66 illegal—have rendered the disputes moot and academic.