# Order Encoding An order signs token quantities, addresses and execution permissions. Its extension carries the rate inputs and callback targets; the signed salt binds those bytes. See the [order contract reference](/docs/integration-reference/evm-limit-orders/orders) for field meanings, pricing and lifecycle methods. ## Signature domain [#signature-domain] The four order address fields use the upstream `Address` wrapper: `uint256` in calldata, with the address in the low 160 bits. `MakerTraits` and `TakerTraits` also encode as `uint256`. EIP-712 instead types the four address fields as `address`, in this exact order: ```text Order(uint256 salt,address maker,address receiver,address makerAsset,address takerAsset,uint256 makingAmount,uint256 takingAmount,uint256 makerTraits) ``` | Domain field | Value | | ------------------- | ---------------------------------------------- | | `name` | `1inch Limit Order Protocol` | | `version` | `4` | | `chainId` | Execution chain ID | | `verifyingContract` | Execution chain's `LimitOrderProtocol` address | `hashOrder` returns the EIP-712 digest. `DOMAIN_SEPARATOR` returns the domain separator. A different chain or settlement produces a different digest. EOA fill signatures use compact EIP-2098 `r` and `vs`; contract fills pass ERC-1271 signature bytes to the maker. Source: [order type and hash](https://github.com/1inch/limit-order-protocol/blob/4.3.2/contracts/OrderLib.sol#L33-L65), [settlement domain](https://github.com/1inch/limit-order-protocol/blob/4.3.2/contracts/LimitOrderProtocol.sol#L31-L44). ## Rate payload [#rate-payload] The payload identifies the registered PT, derivative kind, quote kind and signed APY. It occupies the extension's `customData` tail. For YT orders, the PT still identifies the market; the getter resolves YT from that PT. `customData` is exactly 36 packed bytes, with no ABI tuple padding: | Bytes | Type | Value | | -------- | --------- | ----------------------------------------------------- | | `0` | `uint8` | Version `1` | | `1` | `uint8` | Derivative: `0` PT, `1` YT | | `2` | `uint8` | Quote: `0` underlying, `1` IBT, `2` vault share | | `3` | `uint8` | Flags `0` | | `4..23` | `address` | Registered PT | | `24..35` | `uint96` | Big-endian `impliedApyWad`; 5% is `50000000000000000` | ```solidity function decodeRateOrderData(bytes calldata data) external pure returns (RateOrderDataV1 memory); ``` The decoder returns the fields above in that order, emits no events and reverts with `InvalidRateData()` for another length, version, enum, nonzero flags or zero PT. Market registration, maturity and APY bounds are checked during pricing. ## Extension [#extension] An extension starts with a 32-byte offset header, followed by eight dynamic fields and then `customData`. The header stores cumulative end offsets relative to the first byte after the header. Empty fields repeat the previous offset. | Index | Dynamic field | Content | | ----- | ------------------ | ---------------------------------------------------------------------- | | `0` | Maker asset suffix | Bytes appended to maker-token `transferFrom` calldata. | | `1` | Taker asset suffix | Bytes appended to taker-token `transferFrom` calldata. | | `2` | Making amount data | Packed 20-byte getter address, then getter-local data. | | `3` | Taking amount data | Packed 20-byte getter address, then getter-local data. | | `4` | Predicate | Settlement predicate calldata. | | `5` | Maker permit | Packed 20-byte token address, then permit data. | | `6` | Pre-interaction | Callback data, optionally prefixed by a packed 20-byte target address. | | `7` | Post-interaction | Callback data, optionally prefixed by a packed 20-byte target address. | For cumulative ends `end[0]..end[7]`, encode: ```text offsets = sum(end[i] << (32 * i)) extension = bytes32(offsets) || field[0] || ... || field[7] || customData ``` `customData` starts at `32 + end[7]`; it has no ninth offset. Set the maker's extension flag and bind the low 160 bits of `salt` to the low 160 bits of `keccak256(extension)`. Missing, unexpected or hash-mismatched extensions fail settlement validation. For pre/post-interactions, fields shorter than 20 bytes call the maker with the whole field as data; otherwise, the first 20 bytes select the target. Source: [extension fields](https://github.com/1inch/limit-order-protocol/blob/4.3.2/contracts/libraries/ExtensionLib.sol), [offset slicing](https://github.com/1inch/limit-order-protocol/blob/4.3.2/contracts/libraries/OffsetsLib.sol), [salt binding](https://github.com/1inch/limit-order-protocol/blob/4.3.2/contracts/OrderLib.sol#L153-L161). ### Public fee extension [#public-fee-extension] A public fee order sends payment to `SpectraRateFeeTaker`, which splits it between maker and fee collector. Its receiver, both getters and post-interaction target must name that fee taker. | Index | Field | Bytes | Cumulative end | | ----- | ------------------ | ------------------------- | -------------- | | `0` | Maker asset suffix | Empty | `0` | | `1` | Taker asset suffix | Empty | `0` | | `2` | Making amount data | 20-byte fee-taker address | `20` | | `3` | Taking amount data | 20-byte fee-taker address | `40` | | `4` | Predicate | Empty | `40` | | `5` | Maker permit | Empty | `40` | | `6` | Pre-interaction | Empty | `40` | | `7` | Post-interaction | 20-byte fee-taker address | `60` | Append the 36-byte rate payload: total extension length is `32 + 60 + 36 = 128` bytes. No getter-local or post-interaction extra data is appended. Set the post-interaction flag and leave maker native unwrap clear. For a fee-free rate order, the rate getter likewise requires empty getter-local data, reverting with `NonEmptyExtraData()` otherwise. ### Order-book admission profile [#order-book-admission-profile] The order-book API accepts Spectra's canonical public fee-order profile, not arbitrary 1inch orders. Submit the generated order, including its `extension` and indexed terms, in the [`POST /create` request](/docs/integration-reference/evm-limit-orders/order-book-api#generate-publish-and-list-orders). | Part | Required profile | | ----------------------- | ------------------------------------------------------------------------------------------------------------------------------------------ | | Assets and rate payload | Match the registered PT/YT market, direction and supported quote token. | | Receiver | The configured `SpectraRateFeeTaker`. | | Extension | The exact public fee extension above: both amount getters and post-interaction target the configured fee taker, with no custom extra data. | | Salt | Binds the extension hash. | | Maker traits | The exact partial/multiple-fill, post-interaction, extension and series-0 epoch profile below; no additional flags. | | Indexed terms | `orderType`, `makerTokenType`, `pt`, `impliedRate`, `expiry` and `nonce` must match the decoded signed data. | | Amounts | Positive `makingAmount` and `takingAmount`, in their respective token base units. | Orders that fail this canonical validation are rejected with HTTP 422 and `code: ORDER_VALIDATION_FAILED`. Malformed request bodies return HTTP 400. Passing encoding checks does not bypass signature, funding or live-order admission checks. **The order contains no numeric fee field.** It selects the configured fee-taker contract, which reads its live `fee()`. An alternate fee receiver, different getters or custom fee payloads fail canonical validation. Adding a `fee` property to the JSON request does not override the fee. ## Maker traits [#maker-traits] Maker traits are signed permissions. Partial and multiple fills must both be enabled to use remaining-amount storage and series epochs. Otherwise, settlement uses nonce-bit invalidation. | Bits | Meaning | Public fee-order profile | | ---------- | --------------------------------------------------------------- | ------------------------ | | `0..79` | Low 80 bits of allowed immediate caller; zero allows any caller | `0` | | `80..119` | Expiry, Unix seconds; zero means no expiry | Selected expiry | | `120..159` | Nonce or signed epoch | Current epoch | | `160..199` | Series | `0` | | `247` | Unwrap taker-paid WETH for maker | Clear | | `248` | Maker uses Permit2 | Clear | | `249` | Has extension | Set | | `250` | Check series epoch | Set | | `251` | Call post-interaction | Set | | `252` | Call pre-interaction | Clear | | `254` | Allow multiple fills | Set | | `255` | Forbid partial fills | Clear | Other bits are unused. Series `0` groups the maker's orders across markets; advancing it leaves other series and orders without epoch checks unaffected. The caller restriction compares only low 80 address bits; an exact full-address allowlist requires a separate pre-interaction guard. Upstream expiry fails only when a nonzero expiry is strictly earlier than the current timestamp. An expiry strictly before maturity is an order-construction policy; the rate getter independently rejects execution at maturity. Source: [maker traits](https://github.com/1inch/limit-order-protocol/blob/4.3.2/contracts/libraries/MakerTraitsLib.sol#L10-L46). ## Taker traits and fill arguments [#taker-traits-and-fill-arguments] Taker traits are supplied with each fill. They choose the amount mode, bound execution price and delimit packed fill arguments. | Bits | Meaning | | ---------- | --------------------------------------------------- | | `0..183` | Threshold amount; mask `(1 << 184) - 1` | | `200..223` | Interaction length in bytes, `uint24` | | `224..247` | Extension length in bytes, `uint24` | | `251` | First 20 bytes of `args` are the maker-asset target | | `252` | Taker uses Permit2 | | `253` | Skip maker permit | | `254` | Unwrap maker-sent WETH for taker | | `255` | Maker-amount mode; clear selects taking-amount mode | Other bits are unused. In maker-amount mode, the threshold is maximum payment for the requested maker quantity. In taking-amount mode, it is minimum maker quantity for the requested payment. Zero disables the threshold; clamped fills preserve the proportional price constraint. For an `Args` fill entry point, concatenate: ```text args = [20-byte target, if bit 251 is set] || extension || interaction interaction = [20-byte callback target] || callback data ``` Without the target flag, maker assets go to the immediate caller. Extension and interaction lengths come from their trait fields. No-`Args` methods supply neither extension nor interaction. The batch filler supplies its own target and lengths; see [batch settlement](/docs/integration-reference/evm-limit-orders/quotes-and-execution). Source: [taker-trait masks](https://github.com/1inch/limit-order-protocol/blob/4.3.2/contracts/libraries/TakerTraitsLib.sol#L27-L45), [argument parsing](https://github.com/1inch/limit-order-protocol/blob/4.3.2/contracts/OrderMixin.sol#L451-L482).