BlockShare: A Privacy-Preserving Blockchain System for Secure Data Sharing

In this paper, we presented BlockShare, a blockchain-basedsystem developed to facilitate privacy-preserving data sharing across de-centralized networks. The proposed system enables users to retain controlover their sensitive data while enabling secure, verifiable sharing with au-thorized parties. We implemented an authenticated data structure (ADS)to support decentralized verification and utilized zero-knowledge proofmechanisms to validate conditions without exposing the underlying data.Experimental analysis demonstrated that BlockShare performs efficientlyin constructing data structures, generating proofs, and verifying themwith minimal computational overhead. The platform successfully reducedprivacy risks and enhanced trust in cross-organization data exchanges.