ABSTRACT In 1874, the French colonial state introduced an extensive regime of ethnic surveillance in the port cities of Sài Gòn-Chợ Lớn. This pioneering system in Vietnam relied on an innovative anthropometric science to target Chinese migrants, whose mobile networks posed ongoing concerns for the imperial authority. This article explores the strategies employed by Chinese migrants to navigate the enforced ethnic classifications and regulations imposed by the colonial administration, exploiting the uncertain boundaries between subjects, foreigners, and citizens. It argues that Chinese subversions emerged through a dynamic interplay with the evolving French bureaucratic practices, shaped by the coexistence of two overlapping imperial systems: a decentralized Chinese empire and a French colonial state aiming to consolidate its rule in Cochinchina. The article reveals that French colonial surveillance was not a one-sided, rigid process of panoptic imperial dominance, but rather a complex landscape characterized by negotiated coexistence, mutual collaborations, and acts of resistance.