Fees & rebates

Ophis charges a fee on price improvement only — the difference between the quote you were shown and the price a solver actually delivered. On trades that don't beat the quote, the fee is 0%. There is no flat protocol fee.

The formula

partnerFee = 25% × max(executedOut − quotedOut, 0)
             capped at 0.5% × tradeVolume

• 0% fee on every trade that fills at the quoted rate.
• 25% of the improvement when execution beats the quote.
• Hard cap at 0.5% of nominal trade volume — this protects large trades from paying an outsized fee on chunky positive slippage.

A worked example

Say you ask to swap 1,000 USDC for ETH and Ophis quotes you 0.30 ETH. Solvers compete, and the winning solver actually delivers 0.303 ETH:

	Amount
Quoted output	0.300 ETH
Executed output	0.303 ETH
Price improvement	0.003 ETH
Fee (25% of improvement)	0.00075 ETH
You receive	0.30225 ETH

You still come out ahead of the quote you accepted — the fee only ever takes a share of the extra a solver finds, never your principal. If the solver had only matched the 0.30 ETH quote, the fee would be 0.

How it's collected

The fee is implemented via the CoW Protocol CIP-75 partner-fee model (the priceImprovementBps field in the order's appData). It is taken from the trade output at settlement and routed to the Ophis multisig weekly. Of the partner share, a 25% service fee is retained by the underlying protocol, so Ophis nets roughly 18.75% of price improvement after that.

For the full protocol-level details, see the governance proposal CIP-75 — Partner incentive alignment.

:::note Positive-slippage rebates Because the fee is capped and applies only to improvement, ordinary trades stay free. Traders accrue the upside of solver competition as positive-slippage rebates — track them in the app's Earn and Profile surfaces. :::

Custody of fees

Partner fees accrue to a Gnosis Safe multisig (0x858f…CeF8), deployed deterministically to the same address on every supported chain. See Security & audits for the custody model.