NFT Development Marketplace Royalty Standards (EIP-2981) Questions and Answers

Question 1

An NFT marketplace is processing a sale and needs to determine if it should pay royalties for a given token.
According to the EIP-2981 standard, what is the first step the marketplace's smart contract should take to check for royalty information?

Accepted Answer

Check if the token contract supports the EIP-2981 interface ID (0x2a55205a) via an ERC-165 check.

Answer

Call the `getRoyaltyInfo` function with the `tokenId` and `salePrice`.

Answer

Attempt to transfer 1 wei to a standardized royalty treasury address.

Answer

Query a centralized, off-chain registry managed by a consortium of marketplaces.

Question 2

A developer implements the EIP-2981 `royaltyInfo` function for an NFT collection. For a token with ID `123`, a 5% royalty is due. If this token sells for 10 ETH, what should the `royaltyInfo(123, 10 ether)` function return?

Accepted Answer

A `receiver` address and a `royaltyAmount` of `0.5 ether`.

Answer

A single address and a `royaltyAmount` of `500`.

Answer

An array of recipient addresses and an array of corresponding amounts.

Answer

The royalty percentage (`5`) and the recipient address.

Question 3

What is the core purpose of the EIP-2981 standard in the NFT ecosystem?

Accepted Answer

To provide a universal, on-chain method for signaling royalty information to any marketplace or participant.

Answer

To enforce royalty payments on every `transferFrom` call, preventing unpaid transfers.

Answer

To create a decentralized governance system for setting and updating royalty percentages.

Answer

To automatically split royalty payments among multiple collaborators directly within the token contract.

Question 4

A digital art collective wants to release an NFT where the 10% royalty fee is split equally between the lead artist and a charity. How can this be achieved while remaining compliant with the EIP-2981 standard?

Accepted Answer

The `royaltyInfo` function should return the address of a separate payment splitter smart contract as the `receiver`.

Answer

The `royaltyInfo` function must be modified to return an array of two addresses and the corresponding amounts.

Answer

This is not possible, as EIP-2981 only supports a single royalty recipient.

Answer

The NFT must be listed exclusively on marketplaces that have proprietary, multi-recipient royalty features.

Question 5

Which of the following statements accurately describes the role of marketplaces regarding EIP-2981?

Accepted Answer

EIP-2981 is a voluntary standard, and enforcement of the signaled royalties is a policy decision made by each individual marketplace.

Answer

Marketplaces are required by the standard to block the sale of any NFT that does not implement EIP-2981.

Answer

The standard forces marketplace contracts to automatically execute the royalty payment in the same transaction as the sale.

Answer

Once a marketplace supports EIP-2981, they must honor the royalty percentage, even if it exceeds their platform's maximum fee limit.

Question 6

A developer is implementing EIP-2981 and sets a royalty of 2.5%. The `royaltyInfo` function is called with a `_salePrice` of 1,500 wei. Given that Solidity does not handle floating-point numbers, how should the `royaltyAmount` be calculated to avoid precision loss?

Accepted Answer

By calculating `(1500 * 250) / 10000` using basis points.

Answer

By calculating `(1500 * 2.5) / 100` directly in the function.

Answer

By calculating `(1500 * 25) / 1000` to represent 2.5%.

Answer

By requiring the `_salePrice` to be a multiple of 100.

An NFT marketplace is processing a sale and needs to determine if it should pay royalties for a given token.According to the EIP-2981 standard, what is the first step the marketplace's smart contract should take to check for royalty information?

An NFT marketplace is processing a sale and needs to determine if it should pay royalties for a given token.
According to the EIP-2981 standard, what is the first step the marketplace's smart contract should take to check for royalty information?