Add ERC-8221: Wallet Title Deeds - ERC-721 controlled smart accounts.
Summary
ERC-721 tokens as title deeds for smart contract accounts. Whoever holds the deed operates the account. Transfer of the deed rotates control without moving assets or sharing keys.
The account address is the permanent identity; the controller NFT is the replaceable control mechanism. Key rotation, security model upgrades, and organizational handoffs are NFT transfers - the account’s address, assets, positions, and on-chain history stay fixed.
Account-abstraction properties achieved without new consensus changes:
- Programmable smart-contract wallets
- Key rotation without identity loss
- Alternative signing schemes (post-quantum, passkeys, multisig, zk)
- Social recovery via NFT transfer
- Atomic batching
- Gas sponsorship via signed execution (no ERC-4337 required)
- FOCIL censorship resistance
- VOPS statelessness (no account-specific mempool validation)
- Privacy-pool withdrawal support
Beyond conventional AA:
- Hierarchical account trees (corporate structure as a protocol primitive)
- Approval-scoped risk isolation across accounts under unified control
- Transferable capability containers (child accounts as independently
sellable, delegable, revocable operational units) - Digital inheritance, escrow, and vesting without custodians
- AI agent accounts with hard EVM-enforced spending caps
- Composable account packages deployed as products
- Stablecoin gas repayment via execution hooks
Key design choices:
tokenId == uint256(uint160(account))- no registry, computable by anyone- Transfer lock with mutual exclusion between execution and transfer states
- Control version for universal delegation invalidation on transfer
- Signed execution preserves FOCIL/VOPS (ordinary protocol transactions)
- Optional execution hooks with caller/submitter distinction for policy enforcement
- ERC-4337 optional - for bundler marketplace, not required for gas sponsorship