Ink Protocol is developed by Listia, a P2P marketplace for buying and selling used goods online. Launched in 2009, the marketplace now has over 10 million registered users who have exchanged 100 million items. The company has raised $11MM in venture capital from prominent investors. Listia is introducing a new decentralized reputation and payment system called Ink Protocol, which is powered by the Ethereum blockchain and XNK, an ERC20 compatible token. Ink Protocol helps users safely send and receive payments in P2P marketplaces while earning public reputation for every completed transaction. It greatly enhances the buying/selling process with decentralized reputation and feedback ratings, decentralized escrow for secure payments, third party dispute resolution, and very low transaction costs. Ink Protocol can be integrated into new or existing marketplaces and can also be used in marketplaces that don't directly handle payments (eg, Craigslist and Facebook Marketplace). For sellers, accepting Ink builds up their public reputation, which allows them to start selling quickly on new marketplaces without needing to build reputation from scratch. Buyers can view any seller's reputation across multiple marketplaces and confidently pay using either automated or human-mediated escrow contracts. XNK will be the new currency on the Listia marketplace at launch.