ERC-3643 and ONCHAINID: how it relates to agent payment protocols

Steward: ERC3643 Association (ERC3643 ASBL, Luxembourg); reference implementation in the ERC-3643 GitHub organization, originally built by Tokeny Solutions as T-REX; ONCHAINID maintained in the onchain-id GitHub organization
Status: Final ERC; reference implementation live
Latest version: 4.1.6 highest stable release (archived T-REX repository); the ERC-3643 organization marks 4.1.3 as latest (2025-06-12) (2024-10-18)
Primary source: ERC-3643: T-REX - Token for Regulated EXchanges (external link)

What it is

ERC-3643, titled “ - Token for Regulated EXchanges”, is an ERC-20 compatible token standard that checks the identity of the sender and the receiver on every transfer. It is Final, was created on 2021-07-09 by Joachim Lebrun, Tony Malghem, Kevin Thizy, Luc Falempin and Adam Boudjemaa, and requires EIP-20 and EIP-173. ^{Source [1]}

A token is connected to an Identity Registry that maps each wallet to an identity contract and a country code. The call isVerified(address) passes only when that identity holds the claim topics listed in the Claim Topics Registry, signed by issuers listed in the Trusted Issuers Registry. A Compliance contract answers canTransfer(_from, _to, _amount) on each transfer, so offering rules (investor caps, country limits and similar modules) sit next to the identity check. In ERC-3643 the word “” names an operator role that the token owner appoints to register identities, mint, burn and freeze. ^{Source [1]}

ONCHAINID is the identity half. Its Identity.sol contract descends from the ERC-734 Key Manager and ERC-735 Claim Holder proposals, which exist only as closed GitHub issues 734 and 735 in the ethereum/EIPs repository; issue 734 points to the LSP6 Key Manager and issue 735 carries the status “Discussion”. ERC-725 is still Draft. ^{Source [2, 3, 4, 5]}

In Identity.sol, keys have purposes (1 MANAGEMENT, 2 ACTION, 3 CLAIM signer, 4 ENCRYPTION) and types (1 ECDSA, 2 RSA), and addClaim a purpose-3 (CLAIM) key, a purpose-1 (MANAGEMENT) key, which passes every purpose check, or the identity itself. A claim has topic, scheme, issuer, signature, data and uri. The issuer signs the hash of the identity address, topic and data, and a verifier checks a third-party claim through the issuer contract’s isClaimValid, which lets the issuer side revoke it. ^{Source [2, 6]}

Status

ERC-3643 is a Final, Standards Track ERC. ^{Source [1]} The reference implementation ERC-3643/ERC-3643 is GPL-3.0, not archived, and was last pushed on 2026-08-28; it marks 4.1.3 as “latest” (release published 2025-06-12) with 4.2.0-beta1 as a pre-release. ^{Source [7]} The original TokenySolutions/T-REX repository is archived (last push 2025-10-28); its 4.1.6 release of 2024-10-18 is the highest stable version number. ^{Source [8]} The standard is stewarded by the ERC3643 Association, a Luxembourg ASBL. ^{Source [9]}

How it relates to the eight

Compared with ERC-8004 the two standards answer different questions. ERC-3643 asks “may this wallet hold or receive this regulated token?” and answers with issuer-attested, revocable claims checked on every transfer. ERC-8004 asks “who is this , where are its services, and what do others say about it?” and answers with a permissionless registration, an off-chain and open feedback. Neither covers the other’s job: ERC-3643 has no notion of an agent as a service, endpoint or feedback subject, and ERC-8004 has no issuer-attested compliance and no or delegation model. ^{Source [1, 10]}

Dimension	ERC-3643 plus ONCHAINID	ERC-8004
Status	Final ERC (created 2021-07-09); stewarded by the ERC3643 Association	Draft ERC (created 2025-08-13); community effort
Access model	Permissioned: the holder must be in the Identity Registry and pass `isVerified`, which needs the required claim topics from trusted issuers	Permissionless: any address calls `register()` and receives an ERC-721 agent id
Trust signal	Issuer-signed claims on the holder’s , checked through `isClaimValid`, revocable by the issuer side	Open feedback from any address except owner and operators; validator responses 0 to 100 in a that is specified but not officially deployed
Scope	Transfer compliance for one token	Discovery and trust registry for agents and their services
Who writes	Identity Registry agents register identities; CLAIM or MANAGEMENT keys (or the identity itself) add claims; MANAGEMENT keys manage keys; the token owner manages issuers and topics	Owner or operator writes URI and metadata; any third party writes feedback; a named validator responds
Upgradeability	contracts behind proxies that point to `TREXImplementationAuthority`; ONCHAINID identities can be proxies	proxies at CREATE2 addresses; one EOA holds the upgrade right on Ethereum and Base as of 2026-10-11
Data location	Claims on-chain in the identity contract; `data` may be a hash and `uri` may point off-chain	Registration file off-chain (IPFS, HTTPS) or a data URI; feedback value and tags on-chain; detail files off-chain
Missing	No agent, service endpoint or feedback concept	No issuer-attested compliance and no mandate model

Sources for the table: ^{Source [1, 2, 7, 10]}

If you come from T-REX

A ClaimIssuer you trust plays the part of the you pass to ERC-8004’s getSummary. Claim topics map loosely to ERC-8004 feedback tags: both are labels a reader filters on, but tags are free text written by anyone. The ERC-8004 “Identity Registry” shares a name with the Identity Registry but is a different thing, an directory of agents rather than an allowlist that maps wallets to identities. The T-REX “” role (an operator appointed by the token owner) is also unrelated to an ERC-8004 agent (the AI service itself). ^{Source [1, 2, 10]}

The bridge: ERC-8226

The only standard found that joins the two worlds is ERC-8226 “Regulated Agent Mandate”, a Draft created on 2026-04-12. It treats ERC-3643 or ERC-7943 as the token-compliance layer and ERC-8004 as the agent-identity layer, and adds a layer between them. ^{Source [11]} No ERC3643 Association statement about AI agents or ERC-8004 was found in the pages searched on 2026-10-11; that is an absence of evidence only. ^{Source [9]}

Status history

2017-10-02: ERC-734 Key Manager header date (GitHub issue 734). ^{Source [3]}
2017-10-09: ERC-735 Claim Holder proposed as GitHub issue 735. ^{Source [4]}
2021-07-09: ERC-3643 created. ^{Source [1]}
2024-10-18: 4.1.6 stable release published. ^{Source [8]}
2025-01-16: T-REX 4.2.0-beta2 pre-release. ^{Source [8]}
2025-02-05: T-REX 4.1.7-beta1 pre-release. ^{Source [8]}
2025-06-12: the ERC-3643 organization repository publishes 4.1.3 (marked latest) and 4.2.0-beta1. ^{Source [7]}
2025-10-28: last push to TokenySolutions/T-REX before archiving (the archive date itself is not exposed). ^{Source [8]}
2026-04-12: ERC-8226 created, naming ERC-3643 as a token-compliance layer for agents. ^{Source [11]}
2026-08-28: last push to ERC-3643/ERC-3643 as of 2026-10-11. ^{Source [7]}

Relations at a glance

How ERC-3643 and ONCHAINID relates to each protocol
Protocol	Relation	Note
ERC-8004: Trustless Agents	Complements	Different layers (token compliance versus agent identity and reputation). ERC-8226 composes them; neither spec references the other.

Back to the orbit

Sources

ERC-3643: T-REX - Token for Regulated EXchanges (external link)Ethereum ERCs repository. Specification, primary source. Accessed 2026-10-11.
ONCHAINID Identity.sol (external link)onchain-id (GitHub organization). Repository, primary source. Published 2026-08-12. Accessed 2026-10-11.
ERC: Key Manager (issue 734) (external link)ethereum/EIPs (GitHub). Other, primary source. Published 2017-10-09. Accessed 2026-10-11.
ERC: Claim Holder (issue 735) (external link)ethereum/EIPs (GitHub). Other, primary source. Published 2017-10-09. Accessed 2026-10-11.
ERC-725: General data key/value store and execution (external link)Ethereum Improvement Proposals (eips.ethereum.org). Standard, primary source. Accessed 2026-10-11.
ONCHAINID storage/Structs.sol (Key, Execution, Claim) (external link)onchain-id (GitHub organization). Repository, primary source. Accessed 2026-10-11.
ERC-3643 reference implementation repository (external link)ERC-3643 (GitHub organization). Repository, primary source. Accessed 2026-10-11.
T-REX (archived) (external link)Tokeny Solutions (GitHub). Repository, primary source. Accessed 2026-10-11.
ERC3643 Association (external link)ERC3643 ASBL (Luxembourg). Documentation, primary source. Accessed 2026-10-11.
ERC-8004: Trustless Agents (specification source, ERCS/erc-8004.md) (external link)Ethereum ERCs repository. Specification, primary source. Published 2026-01-25. Accessed 2026-10-11.
ERC-8226: Regulated Agent Mandate (external link)Ethereum Improvement Proposals (eips.ethereum.org). Standard, primary source. Published 2026-04-12. Accessed 2026-10-11.