UniswapV4KEMHook on Ethereum

Uniswap v4 Hook Contract 0x4440854b2d02c57a0dc5c58b7a884562d875c0c4 on Ethereum · Other · Verified contract

Volume (24h)
$392.63K
Value locked (TVL)
$1.29M
All-time volume
$2.16B
Pools using this hook
104
Swaps (24h)
120 (74 traders)
Total swaps
101,704

What it does

A Uniswap v4 hook that only allows exact-input swaps backed by a signature from an authorised quote signer, and captures any output above a signed exchange rate as ERC-6909 claims that a designated account can later redeem to an egRecipient.

How it works step by step

  • Rejects exact-output swaps with ExactOutputDisabled
  • Verifies an EIP-712-style digest over sender, pool key, direction, max amount in, rate, nonce and expiry signed by quoteSigner
  • Consumes unordered nonces to prevent quote replay
  • Computes the output surplus above maxAmountIn times maxExchangeRate divided by exchangeRateDenom
  • Mints the surplus to the hook as ERC-6909 claims and returns it as an afterSwap delta
  • Allows allowlisted claimable accounts to unlock the pool manager and redeem the claims to egRecipient
Swap behaviour
Swaps require hookData containing a signed quote (max amount in, max exchange rate, denominator, nonce, expiry, signature from quoteSigner); exact-output swaps revert. Swaps where the output exceeds the signed rate have the excess taken by the hook.
Liquidity behaviour
No liquidity callbacks.
Fee behaviour
Uses the pool's static fee; beforeSwap returns a zero fee override and no BeforeSwapDelta. Instead, the hook takes an 'exchange-rate guarantee' surplus via afterSwapReturnDelta: if the swap output exceeds maxAmountIn times maxExchangeRate divided by exchangeRateDenom, the excess output is minted to the hook as ERC-6909 claims and the amount is returned as a hook delta.
Owner & admin controls
Owner (Ownable) can update the quote signer, the egRecipient address, and the claimable account allowlist; owner can also call rescueERC20s, rescueERC721s and rescueERC1155s to withdraw any tokens or ETH held by the hook; owner can transfer or renounce ownership. No pause mechanism and no upgradeability found.

Enabled Uniswap v4 callbacks

beforeSwap, afterSwap, afterSwapReturnDelta

beforeSwap: validates signed quote parameters (expiry, max amount in, nonce, signature by quoteSigner) and disables exact-output swaps. afterSwap: computes the exchange-rate surplus on the swap output, mints it to the hook as ERC-6909 claim tokens, and returns the amount as an afterSwapReturnDelta. afterSwapReturnDelta: enabled so the hook can take a share of the swap output.

Security & trust assessment

Risk level: medium (verified source, high confidence).

Who controls it: Not stated.

Risk to user funds: Not stated.

Contract details

Verified source
Yes (UniswapV4KEMHook)
Compiler
solc 0.8.26+commit.8a97fa7a
Bytecode size
10,180 bytes
Upgradeable proxy
No
Detected patterns
ownable, return-delta

Pools using UniswapV4KEMHook