Service contracts for the exploration, development, and utilization of petroleum resources with foreign-owned corporations are permissible under paragraph 4, Section 2, Article XII of the 1987 Constitution, provided they adhere to specific safeguards: (1) the contract must be crafted in accordance with a general law setting standard terms; (2) the President must be the signatory for the government; and (3) the President must report the executed agreement to Congress within thirty days. Furthermore, any activity within a protected area under the National Integrated Protected Areas System (NIPAS) Act, such as exploration for energy resources, requires an Environmental Impact Assessment (EIA) and an Environmental Compliance Certificate (ECC), and if exploitation is involved, a specific law passed by Congress.

The Tañon Strait, a critical marine habitat located between Negros and Cebu, was declared a protected seascape in 1998. Despite this status, the Philippine government, through the Department of Energy (DOE), entered into agreements with Japan Petroleum Exploration Co., Ltd. (JAPEX) for oil exploration in the area, culminating in Service Contract No. 46 (SC-46). This led to concerns from environmental groups and local fisherfolk about the project's impact on the marine ecosystem and their livelihoods.

• On June 13, 2002, the Philippine Government, through the DOE, entered into Geophysical Survey and Exploration Contract-102 (GSEC-102) with JAPEX for geological and geophysical studies in Tañon Strait.
• On December 21, 2004, DOE and JAPEX converted GSEC-102 into Service Contract No. 46 (SC-46), allowing exploration, development, and production of petroleum resources in a 2,850 sq. km. area offshore Tañon Strait.
• Tañon Strait was declared a protected seascape in 1998 under Proclamation No. 1234.
• From May 9 to 18, 2005, JAPEX conducted seismic surveys in Tañon Strait.
• On January 31, 2007, the Protected Area Management Board (PAMB) of Tañon Strait issued Resolution No. 2007-001, adopting JAPEX's Initial Environmental Examination (IEE) and recommending approval of its ECC application.
• On March 6, 2007, the Environmental Management Bureau (EMB) of DENR Region VII granted an ECC to DOE and JAPEX for the offshore oil and gas exploration project.
• On November 16, 2007, JAPEX began drilling an exploratory well near Pinamungajan, Cebu, which lasted until February 8, 2008.
• Petitioners in G.R. No. 180771 are "Resident Marine Mammals" (toothed whales, dolphins, etc.) represented by human "Stewards" Gloria Estenzo Ramos and Rose-Liza Eisma-Osorio, and former President Gloria Macapagal-Arroyo as an unwilling co-petitioner.
• Petitioners in G.R. No. 181527 are Central Visayas Fisherfolk Development Center (FIDEC) and individual fisherfolk representatives.
• SC-46 was mutually terminated by the parties thereto effective June 21, 2008.
• JAPEX Philippines, Ltd. (JAPEX PH) was identified as the Philippine branch office of JAPEX Company, Ltd. (Japan) and its resident agent.

• SC-46 violates Article XII, Section 2 of the 1987 Constitution because JAPEX is 100% Japanese-owned and the contract does not qualify as a valid technical or financial assistance agreement (FTAA) as it was not executed under a general law enacted post-1987 Constitution and lacked presidential notification to Congress.
• Presidential Decree No. 87 (Oil Exploration and Development Act of 1972) is deemed repealed by the 1987 Constitution and subsequent environmental laws.
• The exploration and proposed exploitation in Tañon Strait are inconsistent with Philippine commitments to international environmental laws and instruments.
• The ECC issued for SC-46 is invalid due to the lack of genuine public consultations with affected stakeholders, particularly fisherfolk, prior to its issuance.
• The seismic surveys and drilling activities caused a drastic reduction in fish catch (from 15-20 kilos to 1-2 kilos per day), destruction of "payaos" (fish aggregating devices), and fish kills.
• Fisherfolk were barred from fishing within a 7-kilometer radius from the oil rig, exceeding the 1.5-kilometer exclusion zone stated in the IEE.
• SC-46 violates Section 27 of R.A. 9147 (Wildlife Resources Conservation and Protection Act) by allowing marine exploration of oil and gas, and R.A. 8550 (Philippine Fisheries Code) by infringing on fisherfolk's preferential use of municipal waters.
• Exploration in a NIPAS area like Tañon Strait requires a DENR-approved program and, for exploitation, a general law passed by Congress, both of which are absent.
• Respondents failed to provide petitioners with copies of all documents pertaining to the Tañon Strait oil exploration project despite requests.

• Petitioners Resident Marine Mammals and Stewards lack locus standi as animals cannot be parties to an action, and the Stewards are not real parties-in-interest.
• The issues are moot and academic because SC-46 was mutually terminated effective June 21, 2008.
• SC-46 does not violate the 1987 Constitution as it falls under paragraph 4, Section 2, Article XII (FTAAs), not paragraph 1.
• Presidential Decree No. 87 remains a valid general law for oil exploration service contracts.
• The ECC was issued in accordance with existing laws and regulations.
• Public respondents cannot be compelled by mandamus to furnish petitioners copies of all documents relating to SC-46.
• Petitioners failed to show entitlement to injunctive relief.
• SC-46 does not grant exclusive fishing rights to JAPEX nor impinge on FIDEC's right to preferential use of communal marine and fishing resources; JAPEX did not ban fishing in the project area.
• The declining fish catch is attributable to destructive fishing practices since the 1970s, not the seismic surveys.
• Section 14 of the NIPAS Act, allowing exploration for information-gathering in protected areas (except strict nature reserves and natural parks), is applicable and SC-46 falls under this exception.
• Section 27 of R.A. 9147 (Wildlife Act) prohibits exploration of "minerals," which, as defined in the Mining Act, excludes energy materials like petroleum; thus, it does not apply to SC-46.

• Whether petitioners Resident Marine Mammals and Stewards have locus standi to file the petition.
• Whether former President Gloria Macapagal-Arroyo can be impleaded as an unwilling co-petitioner.
• Whether Service Contract No. 46 is null and void for violating Section 2, Article XII of the 1987 Constitution.
• Whether Service Contract No. 46 is null and void for violating environmental laws, particularly the NIPAS Act (R.A. 7586) and P.D. 1586 (EISS).
• Whether respondents may be compelled by mandamus to furnish petitioners with copies of documents related to the Tañon Strait oil exploration project.

• The Stewards (Gloria Estenzo Ramos and Rose-Liza Eisma-Osorio) have legal standing to file the petition as Filipino citizens under the citizen suit provision of the Rules of Procedure for Environmental Cases, which liberalizes standing for environmental cases, effectively eliminating the need to grant standing to the marine mammals themselves.
• Former President Gloria Macapagal-Arroyo cannot be impleaded as an unwilling co-petitioner; her name was ordered stricken from the title of the case as impleading the President is contrary to public policy and the proper procedure for an unwilling co-plaintiff was not followed.
• Service Contract No. 46 is null and void for violating Section 2, Article XII of the 1987 Constitution. While P.D. 87 can serve as the general law for oil exploration, SC-46 failed to meet two other constitutional requirements for FTAAs: (1) it was not signed by the President of the Philippines but only by the DOE Secretary, and the alter ego principle does not apply when the Constitution requires personal action by the President; and (2) there was no showing that Congress was subsequently notified of the contract.
• Service Contract No. 46 is null and void for violating R.A. 7586 (NIPAS Act) and P.D. 1586. Tañon Strait is a protected area. The seismic surveys conducted under SC-46 were done without a prior Environmental Impact Assessment (EIA) and Environmental Compliance Certificate (ECC) as required by Section 12 of the NIPAS Act and P.D. 1586. While exploration for energy resources is allowed in protected areas (except strict nature reserves/natural parks) under Section 14 of the NIPAS Act, it still requires an EIA and ECC. Moreover, Section 14 requires that any exploitation and utilization of energy resources found within NIPAS areas shall be allowed only through a law passed by Congress; no such law was passed for Tañon Strait.
• The Court did not explicitly rule on the mandamus issue regarding document access, as the primary relief of nullifying SC-46 was granted, rendering other issues unnecessary to discuss. The Court found the petitions meritorious based on the constitutional and environmental law violations.

• Locus Standi (Legal Standing) — The right of a party to appear and be heard before a court. In environmental cases, this has been liberalized by the Rules of Procedure for Environmental Cases, allowing any Filipino citizen to file a "citizen suit" in representation of others, including minors or generations yet unborn, to enforce environmental laws, based on the principle that humans are stewards of nature. Applied here to grant standing to the human petitioners (Stewards) to sue on behalf of the environment, thereby circumventing the issue of whether animals can be petitioners.
• Citizen Suit (Environmental Law) — A suit filed by any Filipino citizen in representation of others, including minors or generations yet unborn, to enforce rights or obligations under environmental laws. This provision liberalizes standing. The Court applied this to recognize the standing of the Stewards.
• Retroactive Application of Procedural Rules — Rules of procedure may be applied retroactively to actions pending and undetermined at the time of their passage, as there are no vested rights in rules of procedure. Applied to allow the Rules of Procedure for Environmental Cases (effective 2010) to benefit the petitioners whose case was filed in 2007.
• Unwilling Co-Plaintiff (Rule 3, Section 10, Rules of Court) — If the consent of a party who should be joined as plaintiff cannot be obtained, they may be made a defendant, and the reason stated in the complaint. This rule was invoked to show the impropriety of simply naming former President Arroyo as an unwilling co-petitioner without her consent and without making her a defendant.
• Presidential Immunity from Suit (and related public policy) — Public policy dictates against embroiling the President in suits to ensure the exercise of Presidential duties free from hindrance. This was a consideration in striking out former President Arroyo's name.
• Jura Regalia — The principle that all natural resources are owned by the State. This is enshrined in Article XII, Section 2 of the 1987 Constitution and forms the basis for state control over their exploration, development, and utilization. The case revolves around the proper exercise of this state ownership and control.
• Financial or Technical Assistance Agreements (FTAAs) (Article XII, Section 2, 1987 Constitution) — Agreements the President may enter into with foreign-owned corporations for large-scale exploration, development, and utilization of minerals, petroleum, and other mineral oils, subject to a general law and other conditions. The Court affirmed that these are the "service contracts" referred to in the 1973 Constitution, but with added safeguards. SC-46 was evaluated against these FTAA requirements.
• Alter Ego Principle / Doctrine of Qualified Political Agency — Acts of department secretaries, performed in the regular course of business, are presumptively acts of the Chief Executive, unless disapproved or reprobated by the latter. This principle was held inapplicable where the Constitution or law requires the President to act in person, as in the signing of FTAAs for natural resource exploration.
• Constitutional Supremacy — If a law or contract violates any norm of the constitution, that law or contract is null and void. This was applied to nullify SC-46 for failing to meet constitutional requirements.
• Statutory Construction (Harmonization of Laws) — Statutes must be interpreted and brought into accord with other laws to form a uniform system of jurisprudence. Efforts should be exerted to harmonize laws, and implied repeals are not favored. Applied in determining that P.D. 87 was not impliedly repealed by the Constitution but must be read in conjunction with it and other laws like the NIPAS Act.
• Statutory Construction (Statute Construed as a Whole) — A statute is passed as a whole, and each part or section should be construed in connection with every other part or section to produce a harmonious whole. Applied to interpret Sections 12 and 14 of the NIPAS Act, concluding that Section 14 (survey for energy resources) does not exempt proponents from the EIA requirement in Section 12.
• Environmental Impact Statement (EIS) System (P.D. 1586) — A system requiring projects in environmentally critical areas or projects deemed environmentally critical to secure an Environmental Compliance Certificate (ECC) prior to commencement, after undergoing an Environmental Impact Assessment (EIA). Tañon Strait, being a protected area, is an environmentally critical area. SC-46 activities (seismic surveys) were found to have violated this by proceeding without a prior ECC.
• National Integrated Protected Areas System (NIPAS) Act (R.A. 7586) — Law establishing a comprehensive system of integrated protected areas to preserve biodiversity. It imposes requirements for activities within protected areas, including EIA, ECC, and for energy exploitation, a specific law from Congress. Violated by SC-46 operations in Tañon Strait.
• Moot and Academic Principle (Exceptions) — General rule that courts will not decide moot cases. Exceptions include: grave violation of the Constitution, paramount public interest, need to formulate controlling principles, and cases capable of repetition yet evading review. The Court found these exceptions present to proceed with the case despite SC-46's termination.

• "In light of the foregoing, the need to give the Resident Marine Mammals legal standing has been eliminated by our Rules, which allow any Filipino citizen, as a steward of nature, to bring a suit to enforce our environmental laws."
• "Under the doctrine of constitutional supremacy, if a law or contract violates any norm of the constitution that law or contract whether promulgated by the legislative or by the executive branch or entered into by private persons for private purposes is null and void and without any force and effect."
• "While Presidential Decree No. 87 may serve as the general law upon which a service contract for petroleum exploration and extraction may be authorized, the exploitation and utilization of this energy resource in the present case may be allowed only through a law passed by Congress, since the Tañon Strait is a NIPAS area."
• "Surveying for energy resources under Section 14 [of NIPAS Act] is not an exemption from complying with the EIA requirement in Section 12; instead, Section 14 provides for additional requisites before any exploration for energy resources may be done in protected areas."

• Oposa v. Factoran, Jr. — Cited by petitioners for the concept of intergenerational responsibility and the right to a balanced and healthful ecology. The Court noted its permissive stance on locus standi in environmental cases even before the Rules of Procedure for Environmental Cases.
• La Bugal-B'laan Tribal Association, Inc. v. Ramos — Heavily relied upon by the Court for its detailed discussion on Article XII, Section 2 of the 1987 Constitution, clarifying that "agreements involving either technical or financial assistance" are service contracts with safeguards. The three safeguards enumerated in La Bugal (general law, President as signatory, Congressional notification) were key to finding SC-46 unconstitutional.
• Sierra Club v. Rogers C.B. Morton — Cited by petitioners in relation to Justice Douglas's dissenting opinion advocating for legal standing for inanimate objects (like the environment). The Court acknowledged this view but resolved standing based on its own Rules.
• Systems Factors Corporation v. National Labor Relations Commission — Cited to support the retroactive application of procedural rules (like the Rules of Procedure for Environmental Cases) to pending actions.
• Heirs of San Miguel v. Court of Appeals — Cited for the principle that law is deemed written into every contract and provisions of positive law regulate and limit contractual relations.
• Joson v. Torres — Cited to explain the alter ego principle and its limitations, particularly that it does not apply when the Constitution or law requires the Chief Executive to act in person.
• Manila Prince Hotel v. Government Service Insurance System — Cited for the definition of a constitution and the doctrine of constitutional supremacy, emphasizing that unconstitutional contracts are null and void.
• Villareña v. The Commission on Audit and Republic of the Philippines v. Marcopper Mining Corporation — Cited for the principle that implied repeals are not lightly presumed and laws should be harmonized.
• Pangandaman v. Commission on Elections — Cited for the precept that statutes should be interpreted in harmony with the Constitution.
• Sotto v. Sotto — Cited for the rule of statutory construction that a statute should be construed as a whole, not in parts, to ascertain its general purpose and intent.

• 1987 Constitution, Article XII, Section 2 — The central constitutional provision regarding State ownership of natural resources, State control over their exploration, development, and utilization, and the requirements for agreements with foreign corporations (FTAAs). SC-46 was found to violate its requirements (President as signatory, Congressional notification).
• 1987 Constitution, Article XVIII, Section 3 (Transitory Provisions) — States that existing laws not inconsistent with the Constitution remain operative. Used to argue P.D. 87 remains valid.
• 1987 Constitution, Article II, Section 16 — The State's policy to protect and advance the right of the people to a balanced and healthful ecology. Underpins the NIPAS Act and environmental protection measures.
• Rules of Court, Rule 3, Section 1 — Defines who may be parties to a civil action (natural or juridical persons, or entities authorized by law). Discussed in relation to the standing of marine mammals.
• Rules of Court, Rule 3, Section 2 — Defines real party-in-interest.
• Rules of Court, Rule 3, Section 10 — On unwilling co-plaintiffs. Used to rule against impleading former President Arroyo as an unwilling co-petitioner.
• Rules of Procedure for Environmental Cases, A.M. No. 09-6-8-SC, Rule 2, Section 5 (Citizen Suit) — Allows any Filipino citizen to file an action to enforce environmental laws. Crucial for granting standing to the human petitioners (Stewards).
• Presidential Decree No. 87 (Oil Exploration and Development Act of 1972) — Considered the general law governing oil exploration. The Court held it remains valid but SC-46 failed to comply with constitutional requirements that overlay it. Its Section 5 requires Presidential approval for contracts.
• Presidential Decree No. 1586 (Establishing an Environmental Impact Statement System) — Requires ECC for projects in environmentally critical areas. Section 4 requires ECC before undertaking projects in declared environmentally critical areas. Section 9 provides penalties for violation. SC-46 operations violated this.
• Republic Act No. 7586 (National Integrated Protected Areas System Act of 1992 - NIPAS Act) — Governs protected areas like Tañon Strait. Section 12 requires EIA and ECC for activities outside the management plan. Section 14 provides additional requirements for energy resource surveys and mandates a law by Congress for exploitation. Section 21 provides penalties. SC-46 operations violated this.
• Proclamation No. 1234 (Declaring Tañon Strait a Protected Seascape) — Established Tañon Strait's status, making it subject to the NIPAS Act.
• Proclamation No. 2146 (Proclaiming Certain Areas and Types of Projects as Environmentally Critical) — Identifies environmentally critical areas, making Tañon Strait (as a protected area) fall under the EISS.
• Civil Code, Article 1306 — Stipulates that contracting parties may establish terms provided they are not contrary to law, morals, good customs, public order, or public policy. Used to state that SC-46 terms must conform to the 1987 Constitution.
• Republic Act No. 9147 (Wildlife Resources Conservation and Protection Act), Section 27 — Argued by petitioners to ban oil exploration. The Court did not extensively rule on this specific claim, focusing on NIPAS and PD 1586.
• Republic Act No. 8550 (Philippine Fisheries Code of 1998) — Argued by petitioners as violated by SC-46 by infringing on fisherfolk rights. The Court's nullification of SC-46 addressed this concern indirectly.
• DENR Administrative Order No. 2003-30 (IRR of PD 1586) — Defines "environmentally critical area" and "project" requiring EIA.

• Justice Marvic M.V.F. Leonen — Concurred in the result. Argued that human petitioners in G.R. No. 180771 (Stewards) lack standing to represent marine mammals, as animals cannot be parties and feigned representation should not be allowed; however, petitioners in G.R. No. 181527 (FIDEC et al.) have standing as real parties in interest due to direct injury to their livelihood. Stressed that the Rules on standing are sufficient and further relaxation by allowing animals as parties is unnecessary and could lead to abuse. Maintained that former President Arroyo cannot be an "unwilling co-petitioner." Agreed SC-46 is unconstitutional because it is neither a financial nor technical assistance agreement as contemplated by the Constitution, and P.D. 87 is unconstitutional for allowing service contracts inconsistent with the 1987 Constitution's framework. Emphasized that SC-46 also violated the NIPAS Act as Tañon Strait is a protected seascape, requiring an EIA, ECC, and a specific law from Congress for exploitation, none of which were fully complied with, particularly the lack of an EIA for the initial seismic surveys.