The proliferation of centralized data repositories has precipitated a surge in large-scale security breaches, exposing sensitive personal, institutional, and biomedical records to malicious actors and unauthorized third-party access. Existing encryption paradigms, including Advanced Encryption Standard (AES) and RSA-based schemes, are fundamentally constrained by the necessity of decrypting data prior to computation, thereby creating exploitable attack surfaces during processing. This paper proposes a novel decentralized framework integrating Fully Homomorphic Encryption (FHE), the InterPlanetary File System (IPFS), and Ethereum smart contracts to enable privacy-preserving multi-party authenticated data storage and retrieval. The proposed Multi-Auth Party (MAP) protocol enforces cryptographic consensus among all designated signatories before granting data access, thereby eliminating single points of failure and insider threats. The system architecture comprises four layers: a client-side cryptographic layer implementing CKKS and BFV FHE schemes via OpenFHE-WASM; a content-addressed decentralized storage layer backed by IPFS and Filecoin; a blockchain consensus layer enforcing multi-signature authorization through Solidity smart contracts on the Ethereum EVM; and a threshold key management layer using Shamir’s Secret Sharing for distributed FHE key custody. Two concrete deployment scenarios are examined: (1) fraud-resistant AICTE academic governance form submissions in the Indian educational regulatory context, and (2) privacy-compliant genomic data sharing across distributed medical research consortia compliant with GDPR and India’s Digital Personal Data Protection Act 2023. Experimental analysis indicates that FHE introduces computational overhead of approximately 10–100x relative to plaintext operations depending on the scheme and circuit depth; however, the security guarantees and auditability afforded by the architecture substantiate its applicability in high-assurance institutional environments. Gas consumption analysis for the Solidity-based MAP contract confirms economic viability on Ethereum Layer-2 networks, with complete five-party authorization workflows costing approximately USD 0.15–0.40, demonstrating practical institutional deployability.