LibraryPrivacy2022Design paperCorpus record
Minimal Soulbound NFTs
ERC 5192. Tim Daubenschütz , Anders.
ERC 5192, Minimal Soulbound NFTs. It proposes a minimal interface to make tokens soulbound using the feature detection functionality of EIP-165.
Status in the source: Final. A reading of the public specification, not a copy of it and not a certification.
Minimal Soulbound NFTs is worth reading for the rule it actually adds: It proposes a minimal interface to make tokens soulbound using the feature detection functionality of EIP-165.
The five-minute read
The rule
It proposes a minimal interface to make tokens soulbound using the feature detection functionality of EIP-165.
What was already failing
A signature that does not commit to what the user saw can be replayed into a different spend, a different chain, or a different message.
What the number does not mean
The source marks this final. That is a statement about the text, not a promise that every wallet or node has shipped it.
What a builder should be able to point at
An implementation either constrains MUST, NOT, REQUIRED or it is a different design.
One action, walked through
- Open ERC 5192 and read the status line before the examples.
- Write down the rule in one sentence. A fair version of that sentence is: It proposes a minimal interface to make tokens soulbound using the feature detection functionality of EIP-165.
- Name the object that changes: MUST, NOT, REQUIRED.
- Ask what an old client, an old contract, or an offline counterparty does. If the document is silent, the silence is part of the design.
The argument, unpacked
What the text is allowed to settle
Ethereum Request for Comment 5192 can settle the shape of Minimal Soulbound NFTs. It cannot settle whether a later client, a later fork, or a later wallet still does this.
What this page will not pretend
There is no benchmark, no adoption number, and no claim that the mechanism is safe outside the assumptions written in the source.
What has to be true
- You are implementing ERC 5192 at the status the text itself states: Final.
- The object that has to change is MUST, NOT, REQUIRED. A neighbouring document with a similar name is not this one.
- Wallet support is not the same as consensus validity.
What happened after the paper
The source marks this final. That is a statement about the text, not a promise that every wallet or node has shipped it. Later documents can narrow, replace, or ignore this one. Cite the number you mean.
What to check before you use the idea
- What is covered by the signed bytes in Minimal Soulbound NFTs?
- Can the same signature be replayed on another chain, account, or message?
- Which primitive does the text require: MUST, NOT, REQUIRED?
Terms
- ERC 5192
- The public text titled Minimal Soulbound NFTs.
- Final
- The document's own label for how finished the text is. It is not a market fact.
The problem the paper names
A signature that does not commit to what the user saw can be replayed into a different spend, a different chain, or a different message.
What the design proposes
- It proposes a minimal interface to make tokens soulbound using the feature detection functionality of EIP-165.
- A soulbound token is a non-fungible token bound to a single account.
- The Ethereum community has expressed a need for non-transferrable, non-fungible, and socially-priced tokens similar to World of Warcraft’s soulbound items.
How the mechanism is specified
- Taken from the specification, the next constraint is: A soulbound token is a non-fungible token bound to a single account.
- Locate MUST, NOT, REQUIRED in ERC 5192 and apply it to one transaction or call.
- Then check the failure the class of rule always has: a node that did not upgrade, a reverted call, a replayed signature, or a peer that does not speak the message.
What this page does not treat as proven
- A signature scheme is not a privacy system. It hides the signer only if the protocol says so.
- Wallet support is not the same as consensus validity.
- The source marks this final. That is a statement about the text, not a promise that every wallet or node has shipped it.
Why a venture studio still reads it
Use ERC 5192 when a pitch says 'Minimal Soulbound NFTs' without saying whether the rule is consensus, policy, or an interface. The number is the citation. The pitch is not.
This is Blockchain Lab's reading of a public design paper. It is not the paper, not a copy of it, and not an offer of tokens, equity, custody or a partnership. Later network behaviour can diverge from the text. Nothing here is investment, legal or technical advice.
Research status: Design paper. Last reviewed: 1 October 2026. This is a reading of a public paper, not investment, legal or security advice.
