NFT copyright / royalties

NFT Copyright / Royalty

Copyright

stay NFT field , A previously overlooked issue is intellectual property （“IP”） Law . Even in decentralized NFT In the world , Copyright law also applies , Buying 、 Casting 、 You should know their importance before you sell them .

NFT It is an attractive product of blockchain technology , It offers exciting possibilities . for example ,NFT Can make art 、 Industries such as real estate and wine collection are fully democratized , There is no need for the auction house to verify the authenticity of the work , Because buyers and sellers can trade directly . however , In the course of trading , There is a Copyright issues and Legal grey areas .

The rules

** Generally speaking , Any original work , Whether it's music 、 painting 、 Books , Or any other tangible work with minimal creativity , Are protected by federal law .** Although the copyright of artworks lies in artworks “ Fix ” Auto exist after , But the artwork needs to be registered with the U. S. Copyright Office to be protected by law （ That is, the intellectual property holder can sue for infringement damages ）. The copyright and all related intellectual property rights belong to the creator of the work , However, some or all of the rights therein may be assigned or transferred to any subsequent purchaser of the work . Australian legislation or case law does not currently address NFT, This is the case in most other jurisdictions . therefore , of NFT Any legal analysis and comments of are based on IP、IT And the basic principles of commercial law .

Buy NFT Only the purchaser is granted the right to NFT Ownership of the particular copy or edition of the work represented . Copyright law experts Andres Guadamuz What the doctor said ,NFT It's just “ You have an encrypted signature receipt for a unique version of the work ”. Buy NFT Will give the purchaser title to each copy or edition of the underlying work , This is a misunderstanding .

**NFT The casting and sales of are susceptible to “ Copy fraud ” And the infringement of the copyright of the basic works and the infringement of the spiritual rights of the authors of the original works .** When one casts works in the public domain NFT, Falsely claiming to have copyright as the underlying asset of the original work , Replication fraud will occur . Again , When the author or copyright owner of the underlying asset where the copyright exists is not the author or copyright owner , May infringe copyright and moral rights , Casting NFT And distort that they are the author or copyright owner of the work . Due to the anonymous nature of blockchain , This kind of behavior NFT It's a problem , This makes it difficult to verify who is NFT The legal creator or copyright owner of the underlying work .

There is one Twitter post , A name Benyamin Ahmed Of 12 The - year-old programmer described how he could start his own NFT project . He uses a computer to generate 3,350 The article “ Strange whale ”, Sell out almost immediately through marketing stories . All of a sudden , These were originally written as 0.033 ETH（ About then 66 dollar ） The pixelated whale images sold after a few hours in 3 ETH（6,000 dollar ） At the price of .

However , As the hype continues , A user spends time searching on Google “ Pixel whale ”, It seems that the artistic works of the project are directly from Another project Copy it , Used four years ago Pixel image As the basis for all the strange whale images . It's not clear Whether the project constitutes intellectual property theft . The basic image may have been placed in the public domain by the original artist , perhaps Benyamin Ahmed You may have obtained permission to use it . But soon after this potential intellectual property theft was exposed , People began to sell their whales at a loss , The momentum of the project was immediately shaken . Make NFT Whether the person is 12 It doesn't matter if you are old and innocent to do so , Because there is no innocent infringement of copyright .

The United States Copyright Office issued A summary of its basic rules

The copyright and all related intellectual property rights belong to the creator of the work , However, some or all of the rights therein may be assigned or transferred to any subsequent purchaser of the work .

《 American copyright law 》 Make it clear , The copyright is transferred to the copy ：
Transfer of ownership of any material object , Include a copy or tape of the first fixed work , Do not transfer any rights in the copyrighted works reflected by the object ; The copyright or any exclusive right under the copyright does not transfer the property rights of any material object .
If you buy oil paintings from artists , You won't get the copyright . If you have original works , But the artist retains the copyright . If they want to , They can sell it in print . If you want to buy the copyright , You need to reach a separate agreement .NFT So it is with , Unless NFT Expressly confer copyright benefits on the owner , Not just visiting art , Otherwise, the owner should not assume that they have the right to use the art or prevent others from using

At present, copyright laws in many jurisdictions basically follow two basic principles

Two basic principles

• The first is to buy or acquire a physical or digital object , But does not give the Purchaser any copyright in the object . For example, the United States Court in ITOFCA, Inc. litigation MegaTrans Logistics, Inc. case As written in “ Copyright does not automatically transfer with the transfer of copyrighted goods , So when you buy a Book , You will not be granted the right to make and sell copies of it .

  The same is true in the digital field , If you buy a picture of a monkey NFT As your avatar , Then without the consent of the monkey picture author , You can't copy it .

• The second is that the ownership of copyright can only be transferred when the author signs a written contract . According to section of the United States Copyright Act 17 USC 204(a) strip ,“ The transfer of copyright ownership is invalid , Unless an instrument of transfer 、 The instrument of transfer or memorandum is in writing and is signed by the owner of the transferred right or his duly authorized agent .” This is to protect artists from divulging their copyright , And ensure a reliable record of copyright transfer . When selling art related NFT when , author Rarely sign anything that transfers any rights to the work .

Ownership of copyright after the transaction

NFT The trading partner under the mode is a copy of digital works as digital commodities , The legal effect of the transaction is the transfer of property rights . According to the relevant rules of the copyright law , When the original or copy of the work is transferred as a thing , Transfer of ownership , however , Of course, the ownership of works' copyright does not change .NFT Digital works are traded , No transfer of copyright , Unless there is a clear agreement on the assignment of copyright , Otherwise, it still belongs to its original copyright owner . In industrial practice , Most of the NFT The trading platform has a copyright reservation clause in the user agreement , Make it clear that NFT The copyright of a digital work is owned by the publisher or the creator of the original work , The buyer has no right to copy 、 issue 、 Adaptation 、 perform …… Digital works .

The copyright of digital works will not be transferred due to token transactions , This also means that the copyright owner sells one NFT After digital works , Still have the right to copy the same digital work , And through the same trading platform or other NFT The platform releases new NFT Digital works . From a technical point of view , Metadata on the blockchain , It corresponds to each token copy of the work , Just the same work , It can produce several copies with the same sample state but different marks . and , The copyright owner can also use different user accounts to distribute NFT, You can also make minor changes to the work , With one “ new ” Works to token transactions . This is not in the property law “ Sell two things for one thing ”, But the copyright owner is exercising his right of reproduction and distribution . however , From the perspective of Economics , The scarcity to be realized by the monetization of the same work will be greatly reduced . For this reason , The copyright owner is distributing NFT Digital works , Naturally, he will consider the market positioning of the work , Maintain its scarcity value by controlling the number of issues .

in fact ,NFT Digital art on the trading platform , More commonly, it is sold online as a single copy , Or sell in limited quantities and state that no new copies will be sold in the future . Some trading platforms clearly state in the user agreement that users are not allowed to repeatedly link the same work , This user agreement is legally binding on platform users . There are some NFT The publisher of , It is clearly stated in the description of the work that it promises not to release the same work in the future NFT.

CryptoPunks

last august NFT The community is just CryptoPunk Copyright debate , come from Punk owner 、 collectors 、 The artist 、 Influencer 、 Opinions of investors and Entrepreneurs . although CryptoPunks The person behind the Larva Labs A license agreement has indeed been written , Grant certain rights to punk owners , But there are still some problems ;

CryptoPhunks The project store is located in OpenSea Get off the shelf twice , Finally, it will be put on the shelves again . This avatar project is original CryptoPunks Replica , There are two small changes ： The image is mirrored , And they add a color border , Indicates the rarity of the feature set .

The last one on twitter CryptoPunk owner @SpottieWifi On twitter , They succeeded in offering CryptoPhunks Sent DMCA Delete request , To get what they have Punk：

About 《 The Millennium Digital Rights Act 》（ Often referred to as “DMCA”）,DMCA Provides a safe haven for service providers hosting user generated content . A single claim for copyright infringement could result in up to 150,000 Legal indemnity in US dollars , As long as the service provider complies with DMCA Notification and deletion rules for , Will not be liable for infringement based on user generated content ,DMCA There are two simple and direct procedures , all GitHub Users should know ：(i) The copyright holder requests to delete the content Delete notification Program ;(ii) When the content is deleted by mistake, the user requests to restore the content Counter notice Program .

Let's see Larva Labs What licenses are there ：

• CryptoPunks x NFT license ：NFT license . It doesn't seem that IP、 The copyright or trademark is transferred to the punk owner . however , The license grants that the artwork can be used for your own personal non-commercial purposes , also You can commercialize your products , At most every year 100K. This Agreement The two things you are not allowed to do are to modify works of art or sell third-party products .

• CryptoPunks x CryptoPunk license ：Larva Labs Have been to CryptoPunks Written a specific copyright license agreement usp=sharing), The Permission is granted only to punk owners to copy 、 Show 、 The right to transmit and distribute their own punk images . There is no mention of commercialization of goods . And there is no copyright 、IP Or the trademark is assigned to the owner in this license .

• CryptoPunks x DMCA Delete request ： Only two types of people can send DMCA Delete request . The copyright owner or the agent of the copyright owner . It is not clear whether punk owners are based on NFT The license is recognized as Larva Labs The agent of .

  at present Larva Labs ** give CryptoPunk What rights does the owner have ？** At present, there are no clear questions answered by the community .

This March Yuga Has gone from Larva Labs To obtain the CryptoPunks and Meebits NFT A collection of IP, Brands with these two series 、 Art copyright and other intellectual property rights , About NFT What rights are granted to the holders of the , The official only said what it planned to do , The first step is ： We will soon Grant CryptoPunks and Meebits Holder and BAYC Holders of the same business rights . We are working with our legal team , Draft new terms and conditions for these two sets , And hope to share these contents with the community soon , Transfer these rights .

CryptoPunks License resources involved ：

NFT license
use CryptoPunks license （ Link failure ）
Meebits Terms and conditions
Avastars Digital asset ownership license
CryptoPhunks declaration

The gray area of copyright

Copyright transfer is a difficult problem , There are also certain grey areas ;
in fact , Make sure NFT Owners' ownership of what they consider copyright is also a more subtle issue than it seems .

Refer to the relevant terms and conditions of the boring ape Yacht Club ： When you buy boring apes NFT When , You have the bottom Bored ape, That is, art , This artwork is copyrighted , Can copy , Exhibition , Selling art copies （T T-shirt, etc ）;

But this clause also has many problems ：

I. Copyright transfer

hypothesis Wodchucklabs（NFT Casting IP merchant ） Apply these terms to WodchuckersNFT. When Alice Buy WodchuckerNFT when , She got the copyright . When she put NFT sell to Bob when , He got the copyright . In terms of copyright , When Alice Buy NFT when , The ownership of the copyright is transferred to Alice, Then when Alice take NFT sell to Bob when , The ownership of another copyright is transferred to Bob.

But the reality is , Copyright does not work this way . American copyright law sets a high threshold for the transfer of copyright ownership .《 Copyright law 》 Article 24 stipulates that ：
Except as required by law , The transfer of copyright ownership is invalid , Signed by the transferor or the owner's duly authorized agent , Unless the instrument of transfer 、 The transfer manual or memorandum is in writing .

There is no problem with the written part . Under federal law , The terms on the website are considered as written terms . If the copyright owner WodchuckLabs Not signed BAYC Clause , No signature , Copyright ownership will not be passed to Alice. Theoretically ,Wodchucklabs You can solve the problem of lack of signature in the first step by modifying the terms and adding signatures . according to 《 Electronic signature law 》, Even digital signatures printed in script fonts can be added to contracts or other records , Or have a logical relationship with the contract or other records , And executed or used by the person who plans to sign the agreement . in fact , Legal opinion , When you create an account , Clicking on the website terms I agree to represents the intention of signing .
There is another big problem . This happens in Alice It was decided that wodchucker Resale to Bob when .BAYC The purpose of the clause is Bob Now it has copyright , and Alice No copyright . But this is because the signature requirement . from Alice To Bob The copyright signature of is not transferred . If there is no signature, transfer ,Alice Still have copyright , instead of Bob.

in fact ,Alice Has called ERC-721 Smart contracts transferfrom（） take bored ape Transferred to the bob, And apply its encrypted signature to NFT Transferred to the bob. but This approach is smart contract terms , Not legal contract terms . The smart contract does not mention copyright or BAYC Link to terms . even so , There's no guarantee Alice Have read and even know these terms . She does not intend to sign legally binding documents by attaching encrypted signatures to transactions related to legal contracts or logic .

II. Alternatives ： Copyright license

Another way to establish NFT The way of copyright is to avoid signing .NFT The founder can use the copyright license , Instead of transferring ownership to NFT owner . The founder holds the copyright , And directly to each successive NFT The owner provides the license .

This method has a big advantage , That is, a copyright license does not need to be signed like a copyright transfer .（ in fact , They don't even need to be in writing , Although it is much safer to write the terms of any serious economic transaction .）carol and wodchucklabs No need to rely on alice and bob To get the correct signature transfer . contrary ,wodchucklabs You can simply write its terms , So that each NFT The owner is getting NFT The license is automatically granted immediately after .

This approach has a good precedent for free and open source software licensing . for example ,GNU General public permit say ：
Whenever you pass on the work covered , The recipient will automatically obtain the license from the original licensor , And operate under the premise of complying with the license 、 Modify and disseminate . You are not responsible for executing third party licenses .

NFT An obvious example of this field is RTFKT license , Regulations :

If through the platform to NFT Any digital work or other content provided by the owner as an additional benefit （ Defined in clause ）, On the platform or when downloading Mark as additional benefit . As long as you have the applicable NFT, Any such content will authorize you... Under any license terms proposed at the time of download , Or if you do not propose such terms , As a specific NFT The contents of the terms of ;

NFT Creators need to think carefully about how to structure their terms , With Make sure NFT The owner actually obtains the necessary copyright license , This is much easier than transferring ownership directly ;

III. Derivative power

The problem is that the relationship between this license script and downstream industries is not harmonious . hypothesis Alice Yes 12345 Number wodchucker（NFT）. She allows filmmakers Fern stay 12345wodchuck Create a series of videos based on . According to copyright law , These videos are Derivative （ Translation 、 Music arrangement 、 Dramatize 、 Fictionalization 、 Movie version 、 sound recording 、 Artistic reproduction 、 Abridgement 、 Concentrated or otherwise recast 、 Transform or adapt the form of the work ）,Fern I have my own copyright to these videos . Now? ,Alice Decide to go to Bob sell 12345wodchuck.Fern What should I do with my license ？

One situation is , When she transfers NFT Ownership ,Alice Have 12345 Number Wodchuck Copyright license for , Any sublicense she issues is also valid . When Alice sell to Bob From that moment on , The license stops authorizing . If Fern Continue playing these videos , He will be a copyright infringer ！

The other is that Fern Your license continues to be valid . once Alice Give it to Fern license ,Bob You can't regret it . This protects Fern, Thus protecting Alice Licensing business . But there is a case ,Bob May give Tom Video license , So now there are two competitions WodChucker12345 series .Fern Will be angry , But what can he do ？ If their lawyers are good ,Fern Will insist on Alice Set the video license to exclusive , such Alice You can't allow anyone else to make a video series . But this is Alice and Fern A private contract between .Bob No signature , There's no limit ！Bob Directly from WodChuckerlabs Obtain a copyright license , You can still license the copyright to Tom Of ;

IIII. License and NFT Package together

The license shall be in accordance with NFT Packed together . This often happens in the real estate industry . If Alice There is a piece of land , And conferred Alice Easement （easement）, Let it lay optical cables in a corner of the land （telecorp Telecommunication company ）,Alice Transfer the land property right （Property） Sell to Bob after , The easement still exists . When Bob from Alice When buying land there , He is free to use the land . He not only inherited her land rights （ Such as building houses or planting crops ）, And inherited her duties （ allow Alice Continue operating the cable ）

When Bob from Alice Buy NFT when , He can use his land . If NFT Packed with license , He not only inherited Alice stay BoredApe12345 Rights in copyright ( For example, the right to make photo art prints ), And inherited Alice Any limitation or obligation of ( Such as Fern Exclusive video license for ). Now? Bob Can't authorize Tom Make a second video series .

Maybe this is a good solution . Maybe not. . If Alice It is now possible to freely protect the copyright of works of art in this way ,Bob Your rights will be limited . When he buys NFT when , What he buys is inferior to Alice All right to buy good . because Alice Divided the copyright , Actually reserved a part for yourself . If Bob stay NFT Market purchase NFT Before , He will have to investigate what he bought NFT The whole chain of ownership , To make sure that Alice didn't quietly divide some of the copyright before him . But this demand for investigation runs counter to the spirit of public and chain encryption as much as possible . therefore , The exclusive license signed by the owner shall not be in connection with NFT Run together .

We have listed three sales NFT Three different possibilities ：
1. End Fern license .
2.Fern Your license remains valid , but Bob The same rights may be granted to Duke.
3.Fern The license continues to be valid ,Bob The same rights cannot be granted to Duke.

As you can imagine , If there is a copyright dispute , The Court adopted any of these three results . in fact , There is no clear consensus on which is the best solution .

These are all NFT Issues that need to be addressed by the license . otherwise ,NFT Owners and their business partners may be dissatisfied with the results . Each is based on NFT But those who do not answer these questions have great confidence in the court . If the transaction deteriorates , Both parties eventually sue each other , The court will deal with the matter .

many NFT The project aims to Transfer of copyright and NFT Ownership itself . This is the same core design goal as creating attractive content and irrevocable transfer . However , Many projects seem far below technology and Art .
The legal infrastructure of blockchain is as complex as the technical infrastructure , Full of pitfalls . Although some cryptocurrencies and Web3 The project aims to break away from the existing legal system or completely replace them , But many creative NFT This is not the case with the project . They are designed to work in the current legal system , Allow people to create new 、 Interesting art , And use real-world contracts 、 Commercialization of property and copyright laws .
added NFT founder , They should also pay attention to the laws and regulations they rely on , Otherwise the result could be disastrous .

Royalty

NFT Royalties are automatically paid to authors in secondary sales . These are encoded into smart contracts on the blockchain . Every time a second sale occurs , Smart contracts will ensure NFT The terms of are fulfilled . If royalties are specified , Then part of the profits will go to the artists who created them .

No mediation is required , Nor does it depend on the will of the trader . Please note that , Not all NFT Will generate royalties . It must be specifically written in the terms . Once the smart contract terms are clearly written into the blockchain , The rest will be handled automatically .

The same applies to digital content 、 Game accessories 、 Physical objects, etc .NFT Royalties can maximize the income of artists and content creators . The good thing about artists is , They often get paid for what they have made . Besides , As their popularity increases , They will eventually get more and more rewards for their work .

majority NFT As a ERC-721 Made of tokens , Royalties and transaction costs generated by each platform are mainly actually incurred , This means that when artists first sell their work to buyers , Whether to obtain the secondary resale share and how much proportion of the share depends on the market in which the transaction actually takes place

Royalty standards (EIP-2981)

Why use EIP-2981？

There are many NFT The market has a variety of unique royalty payment realization , These implementations are not easily compatible or used in other markets . Like in the early days ERC-20 Like tokens ,NFT Market smart contracts vary by ecosystem , And there is no standardization . this EIP Enable all markets to retrieve a given NFT Royalty payment information . No matter what NFT In which market to sell or resell , This can achieve accurate royalty payment .

This standard allows support for ERC-721 and ERC-1155 Interface NFT Send royalty information in a standardized way

The royalty amount is always a percentage of the sales price . If the market chooses No Implement this EIP, No funds will be paid for the second sale .

If there is no agreed royalty payment standard ,NFT Ecosystems will lack effective means to collect royalties in all markets , Artists and other creators will not be able to get sustained funding . This will hinder NFT Growth and adoption of , And weaken NFT The initiative of the creators to create new and innovative tokens .

Open royalty payment standards are not common in Ethereum ecosystem . Royalty information is isolated from the market , Usually not shared . This means that if NFT Remove from the platform and sell , Creators will not receive royalties they are entitled to ;

EIP-2981 It's a standard , Focus on sending given... To market participants NFT Or a group NFT Royalty payment information . It allows you to attach royalty information to the token itself , Thus make use of all A common data store and computing layer that participants can access ( That is, Ethereum network ).

How it works ？

pragma solidity ^0.6.0;
import "./IERC165.sol";

///
/// @dev Interface for the NFT Royalty Standard
///
interface IERC2981 is IERC165 {
    
    /// ERC165 bytes to add to interface array - set in parent contract
    /// implementing this standard
    ///
    /// bytes4(keccak256("royaltyInfo(uint256,uint256)")) == 0x2a55205a
    /// bytes4 private constant _INTERFACE_ID_ERC2981 = 0x2a55205a;
    /// _registerInterface(_INTERFACE_ID_ERC2981);

    /// @notice Called with the sale price to determine how much royalty
    // is owed and to whom.
    /// @param _tokenId - the NFT asset queried for royalty information
    /// @param _salePrice - the sale price of the NFT asset specified by _tokenId
    /// @return receiver - address of who should be sent the royalty payment
    /// @return royaltyAmount - the royalty payment amount for _salePrice
    function royaltyInfo(
        uint256 _tokenId,
        uint256 _salePrice
    ) external view returns (
        address receiver,
        uint256 royaltyAmount
    );
}

EIP-2981 The overall goal of the contributors is to provide a savings gas Solutions for , At the same time, avoid restrictions on future royalty payment improvements . The simplicity of its design is intentional , The goal is to make adoption simple . As with any standard , Adoption is the key to practicality ;

In general , For a given NFT_tokenId and _salePrice, The royaltyInfo Function will perform a percentage calculation to generate the necessary （ And indisputable ） Information to make royalty payment transactions .**

Notice how this function relates to NFT Existing standards (ERC-721/1155) It has nothing to do with money . When it comes to more abstract concepts （ Such as sales ） when , What drives them is the market . There are two key operations when sales occurs ：

1. Transfer of funds from buyer to seller
2. NFT Transfer from seller to buyer

** about NFT For smart contracts , It can't judge the call safeTransferFrom Is simply to NFT Moving to another address is also an actual sales event .**NFT Many project parties in the trading market can actually control the collection address of copyright fees at will , Can be set to their own ;

For support EIP-2981 For the market , consider NFT The currency in which sales are denominated is very important . Royalties shall be calculated in the same denomination . market must _salePrice Pay royalties in the same exchange unit as passed to royaltyInfo(). This is equivalent to saying _salePrice Parameters and royaltyAmount Return value must Denominated in the same currency unit . for example **, If the selling price is ETH, Royalties must also be paid in ETH payment , If the selling price is USDC, Royalties must also be paid in USDC payment **.

Royalty payment percentage calculation

The EIP Using a percentage based royalty model ： The most common case for percentage calculation may be royaltyAmount Is always _salePrice Calculate using a fixed percentage , That is, if the royalty is 10%, No matter _salePrice yes 10、10000 still 1234567890, Must pay 10% Royalty of .

Also support Diminishing royalties ： The main thing is to make sure royaltyInfo() The commutative unit of a function , And in the percentage calculation Avoid unpredictable variables . Implementer Sure Choose to change the percentage value based on other predictable variables that do not assume exchange units . for example , Percentage values may decrease linearly over time . Methods like this No Should be based on unpredictable variables ,block.timestamp But based on other more predictable state changes . A more reasonable method can Use NFT To determine which percentage value to use to calculate royaltyAmount. The idea is that NFT The percentage value may decrease after each transfer ., If the following events occur , Some nuances can be highlighted ：

1. The market sells NFT.
2. The market will delay... Before invoking and sending payments X A few days .royaltyInfo()
3. If no delay occurs , The market received Y The amount of is different from the amount calculated a few days ago royaltyAmount Significant differences .
4. Royalty recipient dissatisfied with market delay , therefore , They raised a dispute .

Step royalty ： When the selling price is lower than 100 Dollar time ,royaltyAmount by 0 No royalties ;

General royalty payment

Any other contract can use this interface to return royalty payment information , The premise is that it can uniquely identify assets within the scope of interface constraints . therefore ,ERC-2981 Is a common royalty standard for many other asset types . This standard is consistent with the current ERC-721 and ERC-1155 Standard compatible .

Royalty standards （EIP-4910）

TreeTrunk Technology Inc Submitted to Ethereum foundation NFT New standard draft . Ethereum improvement proposal EIP-4910 Is the first one to be safe on the chain 、 Proposal to charge and distribute royalties to both creators and affiliates immediately and irrevocably .EIP-4910 It eliminates the risk that the centralized platform fails to pay the secondary sales royalties correctly or on time .

at present , There are still many that cannot be immediately 、 direct 、 Safely distribute royalties on subsequent sales on the chain . A centralized platform is required to perform this operation . This means that royalties will not be paid immediately when sales occur , And there is always the risk that the platform provider may disappear and the creators will not be paid .EIP-4910 That solved the problem

The proposal is based on OpenZeppelin Smart contract toolbox Architecture is the foundation , And expand it to include royalty account management (CRUD)、 Royalty balance and payment management 、 Simple transaction function —— list / Delisting / Buy —— And the ability to track exchange transactions . The royalty management capability allows for “ Father ”NFT With its “ Son ” Connect logically and recursively NFT“ Son ” Have more children to establish a hierarchical royalty structure , This is called royalty tree .

Why use EIP-4910？

To solve the complex inheritance problem , The proposal To the depth of N The recursion problem of the hierarchical tree of is decomposed into N An independent question , Each floor . This can most effectively traverse from the lowest level of the tree up to its root .

How it works ？

The proposal introduces several new concepts as ERC721 Standard extension ：

• Royalty Account Royalty account （RA）
  • The royalty account is attached to each through it NFT tokenId, It consists of multiple sub accounts , These sub accounts can be personal or other RA The account of . The royalty account is identified by the account identifier .
• Account Type Account type
  • This specifies RA A sub account belongs to an individual （ user ） Or another RA. If there is another RA As RA Sub account , The allocated balance needs to be reallocated to the constituent reference RA Your sub account .
• Royalty Split Royalty split
  • Each sub account is in accordance with RA The associated NFT Percentage of sales earned
• Royalty Balance Royalty balance
  • And RA Relevant royalty balance
• Sub Account Royalty Balance Sub account royalty balance
  • With each RA The royalty balance associated with the sub account . Please note that , Only personal accounts can be used for the balance that can be paid . This means that if RA The sub accounts are RA, The final sub account balance must be zero , Because all RA The balance must be allocated to a personal account .
• Token Type Token type
  • The token type is in ETH Or supported ERC 20/223/777 The symbol of the token gives , for example DAI
• Asset ID assets ID
  • This is a tokenIdRA Of .
• Parent Parent
  • This indicates which is RA Belongs to tokenId Direct parent of .tokenId

Royalty account function

Royalty account RUD（ Read - to update - Delete ） Function definition and interface . because RA Is created in the coinage function , Therefore, there is no need to create a separate royalty account .

Casting with a royalty NFT

Casting NFT when , You have to create a RA, And with NFT and NFT Associated with the owner , If there were ancestors , It is the same as that of our ancestors RA Related to . So , standard _safemint Use this function in the newly defined function ,mint And apply various business rules to the input variables .

Distribute royalties

The method of distributing royalties is to interconnect RA The hierarchy of is decomposed into layers , Then process one layer at a time , Each relationship between the token and its ancestor is used to traverse RA chain , Until the Dagen ancestors and associated RA .

Royalty standards （NEP-199）

stay Near On ,NFT There are many standards , But in the area of royalties, only NEP-199 Yes, there are many NFT Standards used in the project

Irreplaceable token standard

• There is no substitute for tokens （NEP-171）
• Irreplaceable token metadata ( NEP-177 )
• Non homogeneous token approval management ( NEP-178 )
• Irreplaceable token enumeration （NEP-181）
• Non homogeneous token royalty payments ( NEP-199 )

NEP-199 Is an extension interface **, allow NFT Contracts require financial contracts to be paid to multiple recipients , So as to realize flexible royalty implementation **.

Why use NEP-199？

NEAR Upper NFT Support owner_id, But there is a lack of flexibility in terms of ownership and payment mechanisms , More complicated , Including but not limited to royalties .

The core objective of the standard is Define a set of methods called by financial contracts , Used to query the payment object and payment amount .

How it works ？

This payment extension standard is NFT The contract adds two methods ：

• a view method: nft_payout, Accept One token_id and some balance, Returns the specified token Of Payout.
• Calling method ：nft_transfer_payout, Accept All parameters of nft_transfer, Add some Balance Calculation Payout、 call nft_transfer And return Payout Mapped fields .

The market performs cross contract calls and invokes NFT The contract nft_transfer Methods will NFT Transfer to the buyer . Once the function is completed , The market will pay the seller the correct amount paid by the buyer

How to expand NFT 171 Standards to support royalties

As the perpetual royalty will be based on each toekn, Can safely change TokenandJsonToken structure . You need to add some methods to track how much percentage each account with royalties should have

This approach should be able to shift like the old solution NFT, But there is an added benefit It can accurately tell the market which accounts should be paid and how much . If you implement a method to transfer NFT, Then calculate exactly which accounts will be paid and how much will be paid according to the incoming balance

Add royalty information to the structure .nft-contract/src/metadata.rs File and add royalty To Token,JsonToken In the structure ：

pub royalty: HashMap<AccountId, u32>,

In order to simplify the payment calculation , You also need to add a royalty_to_payout Function to src/internal.rs. at present Convert percentage to actual amount payable . To allow less than 1% Percent of , It can be for 100% Appoint 10,000. This means that you can give The minimum percentage is 0.01%, namely 1

If you want this account benji.testnet Have 20% Permanent royalties , You can put this pair of "benji.testnet": 2000 Insert into payout in

//nft-contract/src/internal.rs
//convert the royalty percentage and amount to pay into a payout (U128)
pub(crate) fn royalty_to_payout(royalty_percentage: u32, amount_to_pay: Balance) -> U128 {
    
    U128(royalty_percentage as u128 * amount_to_pay / 10_000u128)
}

If you want to use this royalty_to_payout Function Union 2000 As 1 NEAR Of royalty_percentage and Pass in amount_to_pay, It will return 0.2 NEAR Value

Let's look at the contract payout Code ：

This function will traverse the royalty of the token map, And use royalty_to_payout Convert the previously created function to an expense .

A... With the following royalty fields token：

Token {
    
    owner_id: "damian",
    royalty: {
    
        "benji": 1000,
        "josh": 500,
        "mike": 2000
    }
}

If the user calls nft_payout Token and pass in 1 NEAR Balance of , It will traverse the royalty field of the token and put the following insert To payout in ：

Payout {
    
    payout: {
    
        "benji": 0.1 NEAR,
        "josh": 0.05 NEAR,
        "mike": 0.2 NEAR
    }
}

Last , It will insert To the payee and give him 1 NEAR - 0.1 - 0.05 - 0.2 = 0.65 NEAR.

To add support for permanent royalties , edit mint.rs file . Add an optional parameter for permanent royalties . This will decide to buy NFT when , What is the percentage of which accounts royalties are paid

Solana Royalty standards

Solana NFT union It's based on Solana The project group that promotes common standards in the project , Common contractual standards help Solana Sustainable development of ecosystem , And attract the further development of its low-cost and high-throughput blockchain ;

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The standard of this agreement is mainly Metaplex Studio assignment ,Metaplex It consists of two core components ： A chain program and a self managed front end web3 Applications

On this agreement NFT Royalties **,Metaplex Can seamlessly create artist splits on the chain , Tag each collaborator , Set custom percentage , Every NFT It can also be cast through configurable royalty payments **, And then whenever the art is in Metaplex When reselling on the market , These fees are automatically sent back to the original creator .

Flow Royalty standards

stay Flow Of NFT Developing documents in , How to pay royalties ;

The market can collect the information about NFT Royalty information for ：

• Offline methods ：NFT The project behind it can tell the market what it expects from NFT The percentage of royalties earned on sales .
• NFT Metadata ：NFT The project can be based on NFT Metadata standards Appoint “ Royalty ”. Markets can be created in NFT Use this information when selling lists to force payment of royalties .[ at present ,“ Royalty ” View specification does not specify . Welcome from NFT Proposals for marketing projects .]

stay Flow Cast on the chain NFT, The main metadata implementation standard is FLIP-0636 ;

The protocol interface is mainly used for the third-party market , from NFT Take a share of the proceeds of sales , And send it to someone NFT The author of . Every NFT Can have their own royalties ;

In the agreement , Royalty can indicate any alternative token it wants to accept by specifying the type of generic capability ：

pub struct Royalty {
    
    /// Generic FungibleToken Receiver for the beneficiary of the royalty
    /// Can get the concrete type of the receiver with receiver.getType()
    /// Recommendation - Users should create a new link for a FlowToken receiver for this using `getRoyaltyReceiverPublicPath()`,
    /// and not use the default FlowToken receiver.
    /// This will allow users to update the capability in the future to use a more generic capability
    pub let receiver: Capability<&AnyResource{
    FungibleToken.Receiver}>

    /// Multiplier used to calculate the amount of sale value transferred to royalty receiver.
    /// Note - It should be between 0.0 and 1.0
    /// Ex - If the sale value is x and multiplier is 0.56 then the royalty value would be 0.56 * x.
    ///
    /// Generally percentage get represented in terms of basis points
    /// in solidity based smart contracts while cadence offers `UFix64` that already supports
    /// the basis points use case because its operations
    /// are entirely deterministic integer operations and support up to 8 points of precision.
    pub let cut: UFix64
}

cut: Half of the royalty , Usually use 0.0 and 1.0 Representation between ,0.1 Namely 10% Royalty of , Support precision to eight decimal places

receiver： Royalty recipient , Currently only supported flow payment , Official documents will increase the acceptance of a variety of homogeneous tokens in the future

In addition to the royalty standard agreement , Let's see NFT What is the royalty setting of the trading platform **

OpenSea

stay OpenSea On , Royalties are called “ The creator's income ”. The jargon is a little different , But exactly the same .

OpenSea Pay a small portion of each sale in the secondary market to NFT Set Creator . When in OpenSea When collecting on , The platform will prompt you to enter a payment address （ Usually Ethereum ）, You will receive royalties at this address . However ,OpenSea These royalties will not be paid immediately . There is a two-week lock-in period .

How to view the creator fee charged by another collection ？

Go to any NFT The home page of the collection , Then select... From the menu on the right ** Buy now button to filter items sold at a fixed price .** Click any item .

On a single project page , Click now again Buy button . In the pop-up box , You will see... Under the project name Creator fee .

OpenSea What is the average royalties of ？

Opensea The royalty is set to 0-10%. On the other hand ,Rarible Set the royalty to up to 50%

Actual average closer 5%. collect 10% The cost of will increase the buyer's cost , To reduce NFT The attraction of . Can be NFT Royalties are deemed to be buyer's “ Sales tax ”. The lower the price , The greater the demand .

Royalties for projects with large demand ：

Boring ape yacht club founder fee ：2.5%

CryptoPunks Creator fees ：0%

Graffiti creator fee ：5%

Mutant Ape Yacht Club Creator fee ：2.5%

Lazy Lions Creator fees ：7%

Cool Cats NFT Creator fees ：5%

Here you can see the two most popular in the world NFT aggregate （BAYC and CryptoPunks） The creator's fees are 2.5% and 0%.OpenSea Formal advice The creator of the collection will pay royalties / The creator fee is set to 2.5%.

In addition, you can navigate to the favorite editor and adjust The creator's income The percentage charge below the field .

Rarible To create a NFT Royalty

How to be in Rarible Set collection and royalty on

go to Rarible.com And click “ Sign in ”. Connect the wallet as the collection owner in the smart contract

stay Rarible.com Find a collection on - stay Rarible.com
By name in the search bar of （ for example AxieInfinity）、 abbreviation （ for example BAYC） Or favorite address search

• Or click the link https://rarible.com/collection/ Shipping address

On the collection page 3 Click to find **“ Declare ownership ”**
Button if you are the owner of the collection , You should be able to see the new management interface tools .

Add cover 、 Head portrait 、 short / Customize URL, Can also be .gif For pictures

Click on the favorites page 3 Below the dot **“ Set royalties ”**
Button will open a pop-up window , Here you can set the royalties for the selected collection .

Enter the wallet address and custom royalty percentage for each address . Click on **“ Update royalties ”**.
- You can use your wallet address
- Decimals can be used （ for example 0.5%）
- The maximum royalty is 50%. More than any other platform ！
- Don't add 100 Wallet , This will affect the buyer's gas Price .