NFTokenAcceptOffer

The XLS-20 standard for NFTs has a preliminary implementation that can be used in test networks, but is not yet available as an amendment to the XRP Ledger protocol. An amendment may be included in a future XRP Ledger release.

The NFTokenAcceptOffer transaction is used to accept offers to buy or sell an NFToken. It can either:

  • Allow one offer to be accepted. This is called direct mode.
  • Allow two distinct offers, one offering to buy a given NFToken and the other offering to sell the same NFToken, to be accepted in an atomic fashion. This is called brokered mode.

Brokered vs. Direct Mode

The mode in which the transaction operates depends on the presence of the SellOffer and BuyOffer fields of the transaction:

SellOffer BuyOffer Mode
✔️ ✔️ Brokered
✔️ X Direct
X ✔️ Direct

If neither of those fields is specified, the transaction is malformed and produces a tem class error.

The semantics of brokered mode are slightly different than one in direct mode: The account executing the transaction functions as a broker, bringing the two offers together and causing them to be matched, but does not acquire ownership of the involved NFT, which will, if the transaction is successful, be transferred directly from the seller to the buyer.

Execution Details

Direct Mode

In direct mode, NFTokenAcceptOffer transaction fails if:

  • The NFTokenOffer against which NFTokenAcceptOffer transaction is placed is an offer to buy the NFToken and the account executing the NFTokenAcceptOffer is not, at the time of execution, the current owner of the corresponding NFToken.
  • The NFTokenOffer against which NFTokenAcceptOffer transaction is placed is an offer to sell the NFToken and was placed by an account which is not, at the time of execution, the current owner of the NFToken
  • The NFTokenOffer against which NFTokenAcceptOffer transaction is placed is an offer to sell the NFToken and was placed by an account which is not, at the time of execution, the Account in the recipient field of the NFTokenOffer, if there exist one.
  • The NFTokenOffer against which NFTokenAcceptOffer transaction is placed specifies an expiration time and the close time field of the parent of the ledger in which the transaction would be included has already passed.
  • The NFTokenOffer against which NFTokenAcceptOffer transaction is placed to buy or sell the NFTokenis owned by the account executing the NFTokenAcceptOffer.

A side-effect of such failures is the removal of the NFTokenOffer object and the refund of the incremental reserve as if the offer had been cancelled. This necessitates the use of an appropriate tec class error.

If the transaction is executed successfully then:

  • The relevant NFTtoken changes ownership, meaning that the token is removed from the NFTokenPage of the existing owner and added to the NFTokenPage of the new owner.
  • Funds are transferred from the buyer to the seller, as specified in the NFTokenOffer. If the corresponding NFToken offer specifies a TransferRate, then the issuer receives the specified percentage, with the balance going to the seller of the NFToken.

Brokered Mode

In brokered mode, the NFTokenAcceptOffer transaction fails if:

  • The buy NFTokenOffer against which the NFTokenAcceptOffer transaction is placed is owned by the account executing the transaction.
  • The sell NFTokenOffer against which the NFTokenAcceptOffer transaction is placed is owned by the account executing the transaction.
  • The account that placed the offer to sell the NFToken is not, at the time of execution, the current owner of the corresponding NFToken.
  • Either offer (buy or sell) specifies an expiration time and the close time field of the parent of the ledger in which the transaction would be included has already passed.

Fields

Field JSON Type Internal Type Description
TransactionType String UInt16 Transaction type NFTokenAcceptOffer. The integer identifier is 29.
SellOffer String Hash256 (Optional) Identifies the NFTokenOffer that offers to sell the NFToken.
BuyOffer String Hash256 (Optional) Identifies the NFTokenOffer that offers to buy the NFToken.
BrokerFee Currency Amount Amount (Optional) This field is only valid in brokered mode, and specifies the amount that the broker keeps as part of their fee for bringing the two offers together; the remaining amount is sent to the seller of the NFToken being bought. If specified, the fee must be such that, prior to accounting for the transfer fee charged by the issuer, the amount that the seller would receive is at least as much as the amount indicated in the sell offer.

In direct mode, you must specify either the SellOffer or the BuyOffer. In brokered mode, you must specify both the SellOffer and the BuyOffer.

This functionality is intended to allow the owner of an NFToken to offer their token for sale to a third party broker, who may then attempt to sell the NFToken on for a larger amount, without the broker having to own the NFToken or custody funds.

If both offers are for the same asset, it is possible that the order in which funds are transferred might cause a transaction that would succeed to fail due to an apparent lack of funds. To ensure deterministic transaction execution and maximize the chances of successful execution, the account attempting to buy the NFToken is debited first. Funds due to the broker are credited before crediting the seller.

In brokered mode, The offers referenced by BuyOffer and SellOffer must both specify the same TokenID; that is, both must be for the same NFToken.