NFT 2.0

Concept

This section outlines the on-chain and off-chain specifications for NFTs with obligatory royalties.

Problem

On TON, NFTs follow TEP-62 and TEP-64; royalties are defined by TEP-66. To be recognized as an NFT by ecosystem products such as wallets, explorers, and indexers, a smart contract must conform to the interfaces and internal constraints defined by these specifications.

TEP-66, the NFT royalty standard, defines the on-chain layout for royalty parameters but does not impose any rules on how royalties should be enforced across the ecosystem. This is intentional: introducing mandatory on-chain royalty enforcement for auctions or other market mechanisms would interfere with the foundational principles of NFTs. This would mean enforcing royalties at the cost of restricting legitimate, non-commercial transfers — such as gifting or migrating assets between personal wallets. These constraints undermine usability and conflict with the open, decentralized principles that define NFTs.

These limitations have significantly impacted the TON NFT market.

Motivation

For artists and collection creators, royalties from secondary sales are a primary source of revenue. Without a reliable way to enforce them, the initial mint becomes the only guaranteed income. As a result, some community-driven collections have been traded through Web2 platforms instead of on-chain. In such cases, royalty logic is typically bypassed, and profit distribution becomes unfair within the NFT trading ecosystem.

To ensure fair value distribution among all participants — including artists, marketplaces, and sellers — royalty enforcement must be addressed through coordinated off-chain mechanisms.

Solution

The solution for enforcing royalties while maintaining compatibility with existing services and standards involves introducing additional mutable fields in the off-chain metadata. The NFT contracts themselves remain unchanged; instead, the semantics of the metadata associated with each item in the collection are extended. In particular, each item includes a mutable boolean field named royalty_violation, along with a potentially modified image field, in addition to the existing off-chain data standard.

Execution model

The execution model of the proposed royalty-enforcing solution includes both on-chain and off-chain components, working together to abstract blockchain complexity from ecosystem products.

1. Minting and metadata layer: all NFTs are minted on a minting platform that combines on-chain contracts and API.

• On-chain contracts handle actions like minting, burning, etc.
• Off-chain metadata includes pack configuration and sale logic: number of items per pack, royalty rules, and mutable fields (e.g., royalty_violation).

Scope

Refer to the Mint platform API for detailed integration information and endpoints.

2. NFT store integration: NFT stores integrate solely through the mint API and do not interact with smart contracts directly.

Stores can:

• Query available packs and their metadata (e.g., price, available supply)
• Request NFT minting by attaching Toncoin on behalf of a user

3. Enforcing a mutable field: a specific field in the off-chain metadata, such as royalty_violation, is updated to reflect policy changes.

These updates do not affect the smart contract but are respected by ecosystem products that rely on metadata.

4. Reindexing and propagation: when mutable metadata changes, the Mint Platform API triggers ecosystem products and indexers to reindex the affected items.

Indexers read updated metadata and expose critical flags (e.g., royalty_violation = true) via their APIs.

Royalty violation marking

Royalty payment assurance works through an off-chain signaling mechanism. Suppose a user or service violates the collection’s royalty policy. In that case, the corresponding NFT item is marked as royalty violated. This status does not involve any on-chain transactions or changes to the contract state. Instead, it’s reflected in the off-chain metadata by setting the royalty_violation field to true.

The examples illustrate a standard NFT and the same item when it is marked as royalty violated.

// Standard NFT metadata
{
  "name": "Magic Mushroom #57",
  "description": "Hand drawing brings the NFT an artistic value, while various accessories and materials bring uniqueness and significance in our rapidly changing world.",
  "image": "https://s.getgems.io/nft/c/62695cb92d780b7496caea3a/nft/56/629b9349e034e8e582cf6448.png",
  "attributes": [
    {
      "trait_type": "Material",
      "value": "Wool fabric"
    }
  ]
}

// Royalty violated NFT metadata
{
  "name": "Magic Mushroom #58",
  "description": "Hand drawing brings the NFT an artistic value, while various accessories and materials bring uniqueness and significance in our rapidly changing world.",
  "image": "https://s.getgems.io/nft-local/b/c/687f5a964d396571109281fa/629b9349e034e8e582cf6449",
  "attributes": [
    {
      "trait_type": "Material",
      "value": "Wool fabric"
    },
    {
      "trait_type": "Royalty violation",
      "value": "True"
    }
  ],
  "royalty_violation": true
}

Ecosystem products are expected to restrict functionality for NFTs in this status. To indicate the violation in the UI, the image is replaced with a blurred version labeled accordingly.

If a third-party marketplace or secondary platform offers NFTs with forced royalty trading but does not respect collection-level royalty rules, all NFT items traded on that platform are marked as royalty violated. This strictly limits their availability across the ecosystem: wallets and explorers show these items as royalty violated in collection views, and NFT marketplaces or stores that follow the royalty policy do not allow trading or offers for them. As a result, it is not possible to use restricted items in any service that follows this royalty policy.

The royalty violation process

The flowchart illustrates how a royalty violation results in an NFT being flagged as royalty_violation and how this status is propagated through the ecosystem to user-facing interfaces.

NFT 2.0 royalty policy

Royalty-free operations

Not all NFT-related operations are subject to royalty fees. Some actions — such as ownership transfers without commercial intent — are allowed without triggering a royalty. These operations are considered part of the core NFT protocol and do not represent value-generating events.

List of royalty-free operations

• Ownership transfer without commercial intent
• NFT item donation

Royalty-bearing operations

All operations that involve commercial intent must include royalty payments, as defined by the TEP-66 specification. This includes all market-based NFT trading models, such as auctions and offer mechanisms, as well as NFT-related DeFi use cases like floor perpetuals and staking.

Retrieving royalty parameters

According to the specification, the sales contract must retrieve royalty parameters from the collection contract and calculate payments based on that data.

The easiest way to obtain royalty parameters is by calling the royalty_params() get method on the main collection contract. It returns (int numerator, int denominator, slice destination), where the royalty share is calculated as $\frac{numerator}{denominator}$.

For example, if numerator = 11 and denominator = 1000, the royalty share is 1.1%. The numerator must be less than the denominator. The destination is a slice of type MsgAddress, indicating the address where the royalty should be sent.

Marketplace responsibilities

• Marketplaces that comply with the NFT 2.0 specification are expected to send muldiv(price, numerator, denominator) to the destination address after an NFT sale or any other successful commercial operation.
• Marketplaces SHOULD NOT send royalty payments when the calculated amount is zero.
• Marketplaces MAY deduct gas and message fees required to send the royalty from the royalty amount.

Royalty message format

The TEP-66 standard does not define the body of internal messages used to deliver royalties to the destination. As a result, many existing contracts use different message formats. For backward compatibility, NFT 2.0 does not impose any requirements on the message body, allowing any payload to be treated as a valid royalty message.

Below is an example contract snippet written in Tolk:

// You should retrieve these values by calling the collection's getter method beforehand
struct Storage {
    numerator: uint16
    denominator: uint16
    destination: address
}

// salePrice — the total amount paid for the NFT
fun handleRoyalty(salePrice: coins) {
    val storage = lazy Storage.fromCell(contract.getData());

    val royalty = mulDivFloor(salePrice, storage.numerator, storage.denominator);

    val royaltyMsg = createMessage({
        dest: storage.destination,
        bounce: false,
        value: royalty,
    });

    royaltyMsg.send(SEND_MODE_PAY_FEES_SEPARATELY);
}

fun onInternalMessage(in: InMessage) {
    // Handle the sale
    // and define the actual amount received
    val salePrice = ton("1");
    handleRoyalty(salePrice);
}

For a reference implementation of royalty distribution logic, see the open-source royalty distributor contract on GitHub.

Ecosystem products requirements

NFT 2.0 is a protocol including TEP-66-compatible contracts with an additional off-chain restriction mechanism. The primary difference from other collections is the use of mutable metadata, which can change, according to royalty compliance requirements. If your service caches off-chain NFT item metadata, it must be prepared to reindex affected items periodically — ideally at least once per day — to reflect any updates.

As an alternative to scheduled reindexing, services may expose a public endpoint that allows on-demand cache invalidation for specific collection items.

Example request

GET https://{api-name}/{reindex}/{item-address}

Anyone can call this endpoint to refresh the metadata of a specific NFT item if it changes.

To comply with the NFT 2.0 specification, ecosystem products should restrict user interactions with these NFT items. All standard protocol operations involving these items should be turned off — at least at the UI level. This includes listing restricted items for sale on marketplaces, transferring them to wallets, or engaging in DeFi operations within DeFi protocols.

Ecosystem integration checklist

Wallets

• Check for the royalty_violation field in the metadata.
• If royalty_violation: true, restrict all interactions with the item, including transfers, sales and burns.

Explorers

• Display the royalty_violation flag alongside other metadata fields.
• If royalty_violation: true, display a warning or status label indicating that the NFT violates royalty policy.

Marketplaces

• Exclude NFTs with royalty_violation: true from search results.
• Disable trading functionality for NFTs that violate the royalty policy.

Indexers/APIs

• Include the royalty_violation flag in your metadata response schema.
• Provide endpoints or filters that return only NFTs with royalty_violation: false.

Appendix

NFT 2.0 initial distribution process

This diagram illustrates the full sequence of actions involved in distributing NFT 2.0 items through the mint platform — from request and transaction creation to on-chain execution, indexing, and UI update.

NFT 2.0 initial distribution data flow

This diagram illustrates the end-to-end data flow of NFT 2.0 item distribution through the mint platform, from the initial purchase request to on-chain execution, data propagation, and user interface updates.

See also

• NFT standard: TEP-62
• NFT royalty standard extension: TEP-66