This article examines the accessibility, transparency, and interconnectivity of provenance research in museum collections. While the field originated in efforts to document Nazi-era looting, it now also addresses colonial contexts, state succession, and broader cultural heritage claims. Drawing on web-harvested data from 42 departments across 14 institutions in Germany and the United States, the article proposes a systematic framework for evaluating provenance information. The findings reveal differences in data quality, completeness, and standardization, alongside structural constraints shaped by institutional workflows, technology, and resources. Although digitization has expanded public access to provenance information, we still observe significant gaps between professional guidelines and institutional practices. The article therefore calls for standardized data models, interoperable infrastructures, and sustainable strategies for provenance documentation. By identifying both persistent barriers and emerging opportunities, it underscores the importance of interdisciplinary collaboration, shared standards, and wider public accessibility to strengthen equitable and trustworthy stewardship of cultural heritage.