Proof of Attendance Protocol

The Proof of Attendance Protocol, known as POAP, is a system for issuing digital badges in the form of non-fungible tokens to people who attend an event or take part in an activity. Each badge, itself usually called a POAP, carries artwork, the event name and date, and sits in the holder's crypto wallet as a permanent record that they were there. Event organisers create a design and distribute claim links or codes, and attendees use them to collect the badge, typically free of charge.

POAP began at the ETHDenver conference in 2019 and grew into a widely used tool for conferences, online meetups, communities and brands. Because POAPs are public, collections of them have become a kind of on-chain résumé of participation. They are closely related to ideas about digital identity, reputation and community membership in Web3.

Think of the wristband at a music festival, a ticket stub kept in a drawer, or a stamp in a passport. Each is a small souvenir proving that someone went somewhere. A POAP is the digital version: a collectible badge that lives in a crypto wallet instead of a scrapbook.

Unlike a paper stub, the badge carries a time-stamped record that anyone can check, and it cannot easily be lost. Over time, a wallet full of POAPs tells a story about the conferences, classes or online events its owner has joined.

POAP was introduced at ETHDenver in February 2019, where attendees received badges minted on Ethereum. As Ethereum fees rose, the project moved most minting to the low-cost xDai chain in 2020, a network that later became Gnosis Chain after merging with the Gnosis project. The shift to online events during the COVID-19 pandemic broadened its use beyond in-person gatherings, since badges could be claimed from anywhere, and the NFT boom of 2021 brought POAPs to many communities, artists and companies outside the crypto conference circuit. The project has since added mobile apps and ways to claim badges without first setting up a wallet.

1. Creation. An organiser submits a design and event details through the POAP platform, which approves the "drop".
2. Distribution. The organiser receives a method for handing out badges, such as unique claim links, QR codes shown at the venue or a secret word announced during an online session.
3. Claiming. Attendees claim the badge to a wallet address, an email-linked account or a name such as an ENS domain. The token is minted at that point.
4. Display and verification. POAPs can be viewed in POAP's own apps and in many wallets and NFT galleries, and anyone can verify their origin on a blockchain explorer.

Most POAPs are minted on Gnosis Chain, an Ethereum-compatible network with very low fees, so that attendees do not have to pay network costs. Holders can move a badge to the Ethereum main network if they wish, paying the gas fee themselves. Technically, POAPs follow the ERC-721 standard used for other NFTs.

• Event souvenirs. The original and most common use, for conferences, hackathons, concerts and sports events.
• Community access. Projects use POAP ownership to grant access to private channels, voting rights or later events.
• Rewards and eligibility. Some projects use POAPs as evidence of early participation when deciding who qualifies for an airdrop or allowlist.
• Education. Course organisers issue POAPs as lightweight certificates of completion.
• Marketing. Brands use them to reward customers who attend launches or complete online activities.

A POAP shows that a wallet claimed a badge, not that a particular person physically attended. Claim links can be shared or sold, and when POAPs are used to decide eligibility for rewards, people may farm them with many wallets, a form of Sybil behaviour that undermines their value as proof. Organisers have responded with one-time codes, location checks and limits on claims, and some projects combine POAPs with stronger proof of personhood tools. Because POAPs are public, they also reveal where and when a wallet's owner has been, which raises data privacy concerns if a wallet is linked to a real identity. Most POAPs have little or no resale value, and the protocol discourages treating them as investments; their worth lies mainly in what they say about participation.

POAPs show a use of NFTs that is about records rather than trading. Similar ideas include non-transferable "soulbound" tokens, proposed in 2022 as a way to represent credentials that cannot be sold, and on-chain attestations used for reputation systems. Together they are part of a wider effort to build identity and reputation layers on public blockchains, alongside standards such as the decentralised identifier.

• POAP