More partners filed, less network seen: supply chain visibility quality in mandatory reporting regimes

Supply chain visibility depends not only on how many partner relationships are declared but also on whether those partners can be identified in the public record. Using a panel comprising 24,515 firm-year observations from 4524 Chinese listed firms for 2017–2024, together with an archive covering 2010–2024 for structural-break analysis, we construct naming rates and undisclosed shares based on from declared supplier and customer relationships. A structural shift emerges around 2017: participation in relationship declarations expands, but naming rates fall by seven percentage points for both suppliers and customers, while the shares of undisclosed relationships rise. Cross-industry, within-firm and balanced-endpoint tests confirm the pattern, and state-owned firms show steeper deterioration than private firms. The main contribution is to show that broader partner declarations can coincide with weaker operationally usable network visibility: traceability is a distinct quality dimension of supply chain information, not a by-product of broader reporting coverage.