Gray Zone Tactics Playbook: Intrusive Patrolling

China Coast Guard vessels regularly and visibly conduct intrusive patrols deep within the exclusive economic zones of neighboring countries, an activity meant to establish a continuous presence and gradually normalize Chinese jurisdiction over areas granted to its neighbors under international law.
Gaute Friis | NOVEMBER 22, 2023
Gray Zone Tactics Playbook: Intrusive Patrolling
CCG 2502 and CCG 2901 (Credits: China state media)

Gaute Friis




Intrusive patrolling describes how the China Coast Guard (CCG) routinely patrols within the exclusive economic zones (EEZ) of other states. These patrols are a key component of China's strategy to reinforce its expansive maritime claims in disputed waters. By doing so, China aims to establish a continuous presence and gradually normalize its maritime activities in these areas.

These patrols demonstrate Beijing's resolve to create de facto jurisdiction over areas clearly granted to other nations under the 1982 U.N. Convention on the Law of the Sea (UNCLOS)

China signed UNCLOS in 1996, but claims it is subordinate to the PRC's "historic rights" over the South China Sea.

The persistent presence of CCG vessels can intimidate other claimant states and discourage them from challenging China's maritime assertions. Through such patrolling activities, China effectively employs a strategy of incremental encroachment to strengthen its territorial claims in the South China Sea, gradually altering the status quo in its favor.

As mentioned in our playbook entry for the "going dark" tactic, CCG cutters conducting intrusive patrols often ensure their presence is noticed by engaging in "strategic illumination"—that is, switching their automatic information system (AIS) transponders on as they arrive in the area they will patrol, even if they were previously AIS-dark.


The Asia Maritime Transparency Initiative (AMTI) has extensively covered intrusive patrols for several years, including this March 2023 report on patrols within the Philippines' and Malaysia's EEZs. 

From AMTI report, "Perilous Propects: Tensions Flare at Malaysian, Vietnamese Oil and Gas Fields."

Early this year AMTI provided a rollup of the CCG's intrusive patrols covering all of 2022 with some astonishing numbers:

From AMTI report, "Flooding the Zone: China Coast Guard Patrols in 2022"

Gaute Friis

Gaute is a Defense Innovation Scholar at Stanford's Gordian Knot Center for National Security Innovation.

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