The Philippine Coast Guard has accused a Chinese-flagged seabed survey vessel of broadcasting false AIS positions while holding position roughly 38 nautical miles northwest of Itbayat, in the Batanes island group that sits about 160 km from Taiwan.

In a statement issued Monday, the PCG named the vessel as JIA HAI KE 7 and said its movements were consistent with unauthorised marine scientific research. The vessel ignored repeated radio challenges to identify its intentions and cease any unauthorised activity, according to the coast guard.

The tracking record, as reconstructed by the PCG, exposes the spoofing claim's core. Data showed the ship appearing to move from the coast of Xiamen in southeast China to a position off Papua New Guinea on the same day. It later appeared northwest of Itbayat — a sequence of positions the agency said would have been physically impossible for any real transit. A genuine passage, the PCG noted, would have shown a steady course consistent with innocent passage. Instead, the vessel loitered and held its position.

Open-source information cited by the coast guard identifies JIA HAI KE 7 as a 2,000-ton, 70-metre survey ship designed for marine geological surveys and capable of precise station-keeping. That capability matters. A vessel built to hold a fixed position over the seabed, while concealing its true whereabouts, is not transiting — it is working.

Cables at stake

The commercial stakes extend beyond sovereignty posturing. Waters off Batanes and the Luzon Strait host key submarine cable corridors linking the Philippines with Northeast Asia and the wider Indo-Pacific. The PCG said a survey vessel concealing its position in those waters raises "serious concerns about the security of the country's undersea communications infrastructure and the potential use of any data collected" — including, the agency warned, potential military use.

For shippers, carriers and forwarders with dependence on digital connectivity through the region, the incident is a reminder that subsea infrastructure has become an active theatre of maritime security friction. Cable corridors through the Luzon Strait carry a share of the Philippines' international data traffic, and any physical threat to that infrastructure carries operational and commercial consequences far beyond the naval domain.

The location compounds the sensitivity. Batanes lies on the approaches to the Bashi Channel, the narrow Pacific waterway that the Reuters investigation linked to US contingency planning for countering China's navy. Chinese scholars at Jinan University have previously argued that Batanes belonged to China — a claim Manila rejects but one that underscores why the northern approaches have become a recurring flashpoint in the bilateral relationship.

The Chinese Embassy in Manila did not immediately respond to a request for comment.

AIS spoofing moves to the foreground

The allegation fits a broader pattern of concern across the industry over AIS manipulation. When a 2,000-ton survey ship can broadcast a position off Papua New Guinea while physically loitering northwest of Itbayat, the tracking data that underpins fleet monitoring, risk assessment and compliance screening loses reliability. Vessel-tracking providers, marine insurers and port authorities all depend on AIS integrity; incidents of this kind push verification and cross-referencing of position data up the risk agenda for anyone managing tonnage or cargo flows in contested waters.

The PCG said it would continue monitoring the vessel. With undersea cable corridors, contested maritime claims and great-power naval planning all converging on the strait between Batanes and Taiwan, further incidents of this kind — and sharper responses to them — look increasingly likely as monitoring capability and geopolitical pressure both build.