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FDUSDFiat-backedRank #6

First Digital USD

FD121 Ltd (First Digital)

Market cap (static): ~$1.5B

EIP standards (ERC-20, permit, proxies…)

Overview

Launched June 2023 to replace Binance's BUSD after wind-down. Primarily used for high-frequency trading pairs on Binance and MEXC. Issued by BVI-registered entity (transitioned from Hong Kong in August 2025), reserves held in trust by First Digital Trust.

Features

Engineering-oriented breakdown of capabilities: standards, who they matter for, integration rationale, per-feature risks, and vetted external references (specs, docs, verified source).

Primary Ethereum verified source: Etherscan
FeatureStandardsAudienceWhy it mattersRisk / caveatReferences
EIP-3009 gasless transfers on BSC
authorization
UserGas sponsorship on BNB Chain via `transferWithAuthorization` — enables commerce-style flows similar to USDC.Relayer and nonce handling identical caveats to other EIP-3009 deployments.
Bankruptcy-remote trust structure
compliance
CorporateLegal ring-fencing for reserves — institutional due diligence, not on-chain enforceable.Legal regime and trust deed determine real protection; not visible in Solidity.
Chainlink PoR oracle
compliance
  • Chainlink Data Feeds
  • PoR
BothOn-chain FDUSD/USD feed on BNB — contracts can anchor off-chain logic to oracle answers.Oracle downtime or deviation thresholds can block dependent protocols.
Monthly attestations
compliance
CorporatePeriodic attestations for reserve reporting — ops/compliance monitoring.Attestation lag vs real-time market; not on-chain proof.
Issuer mint/burn/freeze
compliance
  • ERC-20 admin pattern
CorporateCentralized controls typical of fiat-backed issuers — same integration caveats as USDT/USDC.Blacklist/pause can strand positions in smart contracts holding FDUSD.

EIP / ERC support matrix

Standards support for FDUSD. Click an EIP to jump to the global deep-dive section.

StandardStatusNotes
ERC-20
Fungible token standard
ImplementedStandard wallet and CEX integration; DeFi depth is thinner than USDT/USDC.
EIP-712
Typed structured data signing
PartialRequired to build relayer-signed payment flows wherever EIP-3009 is live.
EIP-2612
Permit — gasless ERC-20 approval
UnknownIf permit is absent, DeFi UX falls back to classic approve or Permit2.
EIP-3009
transferWithAuthorization
PartialEnables sponsored transfers on chains where the upgrade is live; critical for payment SDK parity with USDC on those chains.
EIP-1967
Standard proxy storage slots
UnknownProxy detection drives correct ABI attachment in indexers and wallets.
EIP-1822
UUPS — universal upgradeable proxy
UnknownAffects how upgrade safety is reasoned about in audits.
ERC-4626
Tokenized yield vault standard
Not implementedYield requires external protocols.
EIP-1271
Signature validation for smart contracts
Not implementedSmart contract wallets use standard permit only if EIP-2612 exists.

Technical notes

Standard ERC-20/BEP-20 with issuer admin — mint, burn, blacklist. EIP-3009 BSC upgrade (Dec 2025) adds transferWithAuthorization function for gasless BNB Chain transfers. Chainlink oracle: FDUSD/USD price feed on BNB Chain mainnet. Always verify contract address on official docs before integration.

Reserves & peg

Reserves
Cash and cash equivalents held in trust by First Digital Trust Ltd
Collateral
Fiat (off-chain)
Peg mechanism
Hard 1:1 via trust company redemption
Auditor
Independent attestor (monthly)

Ecosystem

DeFi integration
Primarily CEX trading pairs on Binance — limited on-chain DeFi integration
Yield
None

Risk factors

mediumRegulatory transition HK to BVImediumBinance concentrationhighThird-party controversy

Networks & contracts

Deployments by chain — primary rows are highlighted. Always verify addresses against issuer docs before mainnet integrations.

NetworkStandardContractExplorer
EthereumPrimary
ERC-20
0xc5f0f7b66764F6ec8C8Dff7BA683102295E16409
View
BNB ChainPrimary
BEP-20
0xc5f0f7b66764F6ec8C8Dff7BA683102295E16409

Same address, different chain

View
ArbitrumSecondary
ERC-20
0x0000000000000000000000000000000000000000

Address not in static spec — verify native Arbitrum deployment on official First Digital docs before integration.

View
TONSecondary
Jetton
See official FDUSD TON deployment

Native deployment July 2025, Telegram ecosystem

Engineering deep dive

Integration notes

FDUSD is optimised for exchange rails more than deep DeFi composability—verify BSC EIP-3009 support on the deployment you target before building meta-transaction flows.

Ops

Treat attestations and oracle feeds as part of your monitoring stack if you custody or list FDUSD programmatically.