The South China Sea Code of Conduct (CoC) being hammered out between the Association of Southeast Asian Nations and Beijing, if signed without the Philippines’ arbitral victory over China written into it, would legitimize Beijing’s artificial islands and military structures located within the country’s exclusive economic zone (EEZ).

Retired Supreme Court senior associate justice Antonio Carpio, the country’s foremost authority on the maritime dispute, warned in a recent Daily Tribune’s Straight Talk interview that a code that is silent on the 2016 arbitral ruling would in effect freeze the map in China’s favor, allowing Beijing to keep what it has already built on Mischief Reef, which is inside the Philippines’ EEZ.

This would also clear the way for China to build a military base on Scarborough Shoal.

“That will legitimize what they have done,” Carpio said. “And what they will build on Scarborough Shoal, that will legitimize it.”

His warning comes as the Philippines, chairing the Association of Southeast Asian Nations (ASEAN) this year, pushes to close out the long-stalled CoC negotiations with China by the end of 2026 — a deadline ASEAN foreign ministers set in 2023 after the talks had already dragged on too long.

Building stalls code

Carpio traced the impasse to the 2002 Declaration on the Conduct of Parties in the South China Sea, the nonbinding pact under which China first promised to negotiate a binding code “when the time is right.” Twenty-two years later, he said, that time has not come because China is still building.

“They have to build on Scarborough Shoal,” Carpio said. “They want to put an air and naval base on Scarborough Shoal. And after they have done that, they will say: okay, no more island-building, no more reclamation. Everybody stops.”

That sequence, he said, is the core of the problem. A code that preserves the status quo, no new construction, but no rollback of what already exists, would ratify seven years of Chinese reclamation in the Spratlys and any future construction on Scarborough Shoal, a reef that lies well within Philippine waters and figured prominently in the 2016 arbitral ruling.

Carpio recalled that under then foreign secretary Teodoro Locsin Jr., Manila’s position was that it would sign a CoC only if the arbitral award were incorporated into it, and only if Scarborough Shoal and the Spratly Islands were explicitly covered.

Vietnam, he noted, has staked out a parallel red line, insisting that the Paracel Islands, which it disputes with China, be included as well, resisting Beijing’s preference to confine the code to the Spratlys alone.

Those unresolved questions track closely with what Philippine diplomats have publicly called the code’s remaining milestone issues: its geographic scope, whether it will be legally binding, how it relates to the 2002 declaration, and its terms of reference.

Foreign Affairs Secretary Ma. Theresa Lazaro said that this year the negotiators have moved from quarterly to monthly meetings to resolve the issues before the end of 2026, although she has not committed to a firm date and analysts have cautioned that a full agreement is unlikely to be finalized on the current timeline.