Opus is a decentralized music-sharing platform that tackles the issue of music ownership and sharing at an infrastructure and protocol level. Leveraging the speed and redundancy of a novel Interplanetary FileSystem, IPFS, Opus can scale and deliver thousands of tracks per second in a fully decentralized manner. This throughput is achieved by encrypting music tracks on the fly and storing the encrypted music files permanently on the IPFS swarm. Only the decryption keys, and file hashes, are saved immutably on the Opus smart contract. By only storing the decryption keys and reference hashes, we can facilitate a number of novel features such as file ownership, trade, and full decentralization. With Opus, artists can monetize their content by selling permanent access to their IPFS music files and decryption keys directly to a fan¡¯s Ethereum contract, without any middleman. With additional application layers, Opus music players introduce a novel way for users to maintain ownership of music tracks they played across different players and different continents. As everything is transparently stored in the Opus smart contract, we will also facilitate additional governance mechanisms such as a Opus DAO (Decentralized Autonomous Organization) treasury funded from a small percentage of each sale, and an artist bounty system that allows artists to pay a small amount for people to share their tracks.