Blockchain-based e-commerce warranty system using non-fungible tokens (NFTs)

A Smart Contract Framework for Fraud-Resistant and Transferable Product Warranties

Abstract

Traditional e-commerce warranty systems rely on paper receipts or centrally stored digital records that are easily lost, forged, or disputed, and that do not survive a change of ownership when a product is resold. This paper proposes a blockchain-based warranty management system that represents each product warranty as a Non-Fungible Token (NFT) minted to the buyer's wallet at the time of purchase. Built on the ERC-721 token standard and deployed on a low-cost, high-throughput blockchain such as Polygon, the proposed system binds warranty terms, purchase metadata, and claim history to an immutable, publicly verifiable token whose ownership transfers alongside the physical product during resale. A smart contract enforces role-based minting, claim filing and approval, automatic expiry, and revocation, while bulky metadata such as invoices and images is stored off-chain on IPFS and referenced on-chain through a content hash. This paper presents the system architecture, smart contract interface, implementation approach, security analysis, and an evaluation methodology, together with a comparative analysis against conventional warranty systems on fraud-resistance, verification effort, and transferability. The proposed design indicates that an NFT-based warranty layer can substantially reduce warranty fraud and manual verification overhead while introducing a transferable, tamper-evident record that benefits both consumers and manufacturers, particularly in the growing second-hand electronics market.