CSIS Beyond Parallel and Asia Maritime Transparency Initiative commercial satellite imagery and automatic identification system (AIS) data analysis provide the first comprehensive timeline of the development, deployment, and current status of the publicly known Chinese steel structures in the PMZ. What do we know about the three Chinese maritime structures—one integrated management platform and two aquaculture cages—that have been deployed inside the South Korea-China Provisional Measures Zone (PMZ)? What does this mean for Korea-China relations?