Tracing objects owned by anonymous entities

This paper proposes mechanisms for tracing objects (consumer products) without disclosing identities of their owners, while enabling exact owner detections when required. The mechanisms enhance reliability of product-recycling systems while forcing anonymous entities to execute appropriate procedures for maintaining and discarding their owning products. Together with remote monitoring systems, it becomes possible to maintain conditions of products so that safe and efficient uses of them are ensured while protecting privacies of their owners.