Economics
Pool fees
Base fees, dynamic V3 swap fees and the fee modules deployed on Arc.
Arc Mainnet configuration
These are the values set when each pool was created. Read the current pool and module values when quoting because authorized managers can change them.
Every Arc Mainnet V3 pool also has the default 10% unstaked fee share. It is a split of the swap fee paid to unstaked liquidity, not a 10% swap fee. The V2 factory defaults are 0.30% for volatile and 0.05% for stable pools; Arc Mainnet has no V2 market yet. Arc Testnet QA pools use their own fees.
| Market | Tick spacing | Base fee | Dynamic cap | K |
|---|---|---|---|---|
| WETH / USDC | 50 | 0.02% | 0.03% | 2,000,000 |
| cirBTC / USDC | 50 | 0.03% | 0.04% | 2,000,000 |
| WETH / cirBTC | 10 | 0.02% | 0.025% | 1,000,000 |
| USDC / EURC | 1 | 0.01% | 0.015% | 500,000 |
Dynamic V3 swap fees
V3 pools read their swap fee from DynamicSwapFeeModule on every swap: fee = min(base fee + K × |current tick − 10-minute average tick| / 1,000,000, cap). The surcharge rises while the price moves away from its recent average and falls back as the average catches up.
Pools without their own K and cap charge only their base fee. A pool's surcharge also stays at zero until the pool has stored enough price observations to cover the 10-minute window.
The base fee is at most 3% and a cap at most 5%. The swap fee manager sets K and caps; an authorized keeper may adjust base fees only inside manager-set per-pool bounds and step limits. Read the pool's fee() for the fee a swap pays now, and the module's dynamicFeeConfig and keeperBounds for a pool's settings.
V2 pool fees are fixed per pool. CustomUnstakedFeeModule sets the separate unstaked fee share.
Unstaked fee share
Unstaked V3 liquidity keeps 90% of the swap fees it earns; the other 10% accrues in the pool for its gauge. Fees earned by staked liquidity go to the gauge in full and reach voters as fee rewards.
Before TGE, nothing is distributed, so the gauge share accumulates in each pool. The first distribution after emissions begin registers it as fee rewards for that epoch's voters. The unstaked fee manager can change the share per pool at any time.
Network gas
Swap fees and Arc transaction gas are separate costs. Gas is paid from the same USDC balance used by the ERC-20 interface. Estimate the entire batch rather than assuming one batch costs the same as one simple transfer.