Burning Compressed NFTs

Summary

Burning a compressed NFT permanently removes it from the Bubblegum Tree using the burnV2 instruction. This page covers burning by owner, leaf delegate, and permanent burn delegate.

• Burn a cNFT using the burnV2 instruction
• Authorize burns via the leaf owner, leaf delegate, or permanent burn delegate
• Pass the coreCollection parameter when the cNFT belongs to a collection

The burnV2 instruction can be used to burn a Compressed NFT and, therefore, remove it from the Bubblegum Tree permanently. To authorize this operation, either the current owner or the delegate authority — if any — must sign the transaction. The instruction accepts the following parameter:

• Leaf Owner, Leaf Delegate, or Permanent Burn Delegate: The current owner of the Compressed NFT, its delegate authority, if any, or the permanent burn delegate of the collection. If the asset is part of a collection, the coreCollection parameter must be passed. One of these must sign the transaction.

Note that, since this instruction replaces the leaf on the Bubblegum Tree, additional parameters must be provided to verify the integrity of the Compressed NFT before it can be burned. Since these parameters are common to all instructions that mutate leaves, they are documented in the following FAQ. Fortunately, we can use a helper method that will automatically fetch these parameters for us using the Metaplex DAS API.

import { getAssetWithProof, burnV2 } from '@metaplex-foundation/mpl-bubblegum';

const assetWithProof = await getAssetWithProof(umi, assetId, {truncateCanopy: true});
await burnV2(umi, {
  ...assetWithProof,
  leafOwner: currentLeafOwner,
}).sendAndConfirm(umi)

Notes

• Burning is irreversible — the cNFT is permanently removed from the merkle tree.
• If the cNFT belongs to a collection, you must pass the coreCollection parameter.
• The permanent burn delegate can burn any cNFT in the collection without the owner's signature, if the PermanentBurnDelegate plugin is enabled on the collection.

FAQ

Can I undo a burn?

No. Burning permanently removes the cNFT from the merkle tree. The leaf is replaced with an empty hash and cannot be recovered.

Who can burn a compressed NFT?

The current leaf owner, the leaf delegate (if one is set), or the permanent burn delegate (if the collection has the PermanentBurnDelegate plugin enabled).

Do I need to pass the collection when burning?

Yes, if the cNFT is part of a collection. Pass the coreCollection parameter with the collection's public key.

Glossary