• Philippines Positions Itself as “Archipelagic Sentinel” — On the 10th anniversary of the 2016 arbitral ruling against China’s claims, Manila is actively asserting its role as a defender of UNCLOS, freedom of navigation, and a rules-based maritime order in the South China Sea.
• Manila Is Considering Further Legal Action — Philippine officials and experts are pushing for additional arbitration cases against China, including one to establish Scarborough Reef as a common fishing ground and another addressing environmental damage and aggressive actions by Chinese vessels.
• Strategic Vision Emphasizes Sovereignty, ASEAN Autonomy, and Partnerships — Defense Secretary Gilberto Teodoro outlined a four-point approach focused on protecting Philippine sovereignty, upholding international law, preserving ASEAN unity, and building deterrence through alliances with like-minded nations.

On the 10th anniversary of an international tribunal’s ruling invalidating China’s expansive sovereignty claims in the South China Sea, Manila is presenting itself as “the archipelagic sentinel — guardian of the freedom of the seas” and as a potential litigant in additional arbitration cases against Beijing under the United Nations Convention on the Law of the Sea (UNCLOS).

The July 12, 2016, ruling, in a case brought by the Philippines three years earlier, found no legal basis supporting China’s contention of historic entitlements to the resource-rich sea, a vital trade route. China, a signatory to UNCLOS, ignores the ruling and continues harassing other nations’ government and civilian vessels operating lawfully in their respective exclusive economic zones (EEZ).

“This landmark ruling affirmed the fundamental principle that maritime entitlements are derived not from ‘historic rights’ but from international law,” Philippine Defense Secretary Gilberto Teodoro Jr. said in May 2026 at the Shangri-La Dialogue in Singapore.

The Philippines is “on the front line of efforts to assert the integrity of UNCLOS as a constitution of the oceans,” Teodoro said, characterizing Manila as a “hub of convergence among those committed to a rules-based order in the maritime domain.” The starting point is geography, he said, noting the Philippines’ “archipelagic waters are at the heart of busy and vital maritime trade routes that link the Indian and Pacific oceans, making them indispensable to Southeast Asia and the Indo-Pacific. Hence, the Philippines is well-placed to safeguard maritime liberty.”

At the defense conference, Teodoro also introduced the Philippines’ four-point vision to serve as the “archipelagic sentinel,” a concept he credited to maritime law scholar Dr. Jay Batongbacal, a professor at the University of the Philippines College of Law. The principles are: maintaining the Philippines’ sovereignty and territorial integrity; abiding by the international rule of law; protecting the autonomy of the 11-nation Association of Southeast Asian Nations, of which Manila is a founding member; and maintaining deterrence through continued partnerships with nations that share the goal of protecting Manila’s rights and interests under UNCLOS.

The Philippines should consider an additional arbitration case and other legal remedies available through UNCLOS to counter China’s continued coercion, Batongbacal told ABS-CBN News in June 2026. Also that month, retired Philippine Supreme Court Associate Justice Antonio Carpio said Manila should file an arbitration case to establish Scarborough Reef as a common fishing ground in the South China Sea, according to the Philippine News Agency.

China essentially has controlled the reef, which is within the Philippines’ 200-nautical-mile EEZ, since the 2012 standoff that prompted the arbitration case.

“Our fishermen cannot go there anymore, we have to establish a fishing ground and remind the world that that is a common fishing ground, and the fisherfolk can go there anytime,” Carpio said. “We cannot rest on this [2016] arbitral award alone, we have to fortify with more arbitral awards, because that’s the only weapon we have.”

China unilaterally proposed a nature preserve on Scarborough Reef in 2025, a move condemned internationally given Beijing’s history of wreaking environmental havoc with its artificial island-building in maritime areas to which it has no valid legal claim.

Carpio and others also advocated for a multilateral arbitration case in 2024, citing China’s environmental damage at Iroquois Reef in the Spratly Islands and damage to Philippine Coast Guard vessels during a violent encounter in June 2024, when China Coast Guard ships rammed and boarded Philippine vessels attempting to resupply a military outpost at Second Thomas Shoal.

Allies and Partners should continue to uphold UNCLOS to deter aggression, protect nations’ sovereignty, and ensure a free, open and prosperous Indo-Pacific.

• This article was published by Indo-Pacific Defense FORUM

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