2

If you sign a message with intent to list an NFT/token for sale - how does that work if you transfer the item later?

For example on an NFT marketplace - you list your NFT for sale by signing a message. I'm assuming that signed message is a signed transaction to transfer the NFT to a contract that acts as a medium of exchange between buyer and seller.

But what if I sign that message - then transfer my NFT?

  1. List NFT for sale
  2. Site asks for Approval of NFT to be confirmed - tx sent
  3. Site asks for signature with listing details (price, etc)

I now exit site and send the NFT to my friend.
4. Someone fills that listing for the NFT - but my NFT is gone - how is the order filled?

Specifically I'm looking at a site like rarible - where that is the flow - they only get approval and thats it.

But I don't get how it works if you transfer that NFT?

1 Answer 1

2

The Ethereum transactions have a parameter called "nonce" representing the number of transactions sent from the address. You must increment this nonce each time you send a new transaction with the same address. So if you sign a transaction without broadcasting it, then send a new transaction to the network (with the same address and same nonce), the first raw transaction will automatically be rejected by the miners.

To answer (partially) your question that's not a transaction you sign but message data when you list your NFT for sale. Then you can see on their demo that after approving their contract, the user has to send a second transaction to mint the NFT. Are you sure the newly NFT is not sent on the marketplace contract ?

2
  • Right - its signing a message. So whats the purpose of this? Why sign a message? There isn't an NFT minted yet just the contract. edit: after a token is minted - they do ask you to sign another sell order message. So with that signed message - how does it get transferred to their marketplace?
    – Zach
    Jun 27, 2020 at 12:23
  • how does it get transferred to a buyer when sold? Its listed for sale - while still in my wallet, and to buy it I send ETH to their contract - but its in my possession still - so how does that work?
    – Zach
    Jun 27, 2020 at 12:34

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.