Legacy Frax Dollar

Sam Kazemian, Travis Moore and Jason Huan launched FRAX on 20 December 2020. The first mechanism treated collateral as a variable rather than a fixed promise: when the token traded above one dollar the ratio could fall, and when it traded below the ratio could rise.

A redemption at an 85% ratio, for example, returned 85 cents of collateral and 15 cents of newly minted FXS. That was the reason for the phrase fractional-algorithmic. It also meant the dollar token and the volatile share token were joined in the loss-absorption mechanism rather than backed by one segregated cash account.

In October 2021 the protocol shifted minting and redemption toward FraxPoolV3 and AMO controllers. AMOs could lend, trade or place liquidity under governance rules. The original price-triggered formula stopped being the whole system, even though the same FRAX token continued circulating.

FIP-188 made the direction explicit in February 2023: raise the target collateral ratio to 100%, retire algorithmic backing and use growth and retained earnings rather than minting FXS to fill the gap. Current documentation now labels the V1 page historical and retired.

FIP-419 approved frxUSD in December 2024. Today frxUSD is a different upgradeable token at 0xCAcd…6E29. Its mint and redeem contracts accept permitted reserve tokens such as USDC or tokenized Treasury funds. A route works only while its custodian holds collateral and its cap, fee and any reserve-token whitelist permit the transaction.

Then North Star rearranged the signs. FXS became FRAX, veFXS became veFRAX, and the original stablecoin became Legacy Frax Dollar. FIP-441 reported that naming change complete by January 2026. The governance asset now called FRAX is Ethereum contract 0x3432…64D0; it is not the CoinGecko frax asset examined here.

The object behind CoinGecko ID frax is still 0x853d…99e. On 5 September 2026 it returned name Frax, symbol FRAX and total supply 219,320,045.872600381298337455. A new market label did not rewrite this non-proxy contract.

The contract does not pause or blacklist transfers. It does let allowlisted pools mint and burn, and privileged roles can change the pool list, oracles, fees, price settings, controller, owner and timelock. The owner and sole default-admin member resolved to the same 3-of-5 Safe; the timelock was a separate contract. Legacy does not mean ownerless.

FIP-419 drew a chain map in December 2024. It called for automatic upgrades on Fraxtal and the Sei, Mode and X Layer OFTs, plus indefinite 1:1 upgrade contracts on Ethereum and eight Frax Ferry chains. On 21 April 2025, FIP-430 changed the destination: it separated the Legacy FRAX and frxUSD balance sheets and ended the Frax DAO guarantee of 1:1 migration. The proposal points holders to Curve, Balancer, Uniswap and other secondary markets, where execution depends on available liquidity and price rather than a protocol promise at par.

The legacy token contract itself offers transfer and burn, not a claim on a named Treasury fund. Frax’s current engineering notes say LFRAX is being phased out and describe backing that includes fiatcoins, decentralized stablecoins, volatile assets and Fraxlend debt positions. frxUSD uses a narrower reserve system, but its custodian claim, sfrxUSD yield and the renamed FRAX governance vote do not flow backward merely because the family name is shared.