FeeModel.sol

Fee-calculation contract for the Strike CLOB protocol. It performs no transfers; callers such as Vault and BatchAuction move funds.

Inherits: AccessControl.

Fee Schedule

Parameter	Type	Description	Default
feeBps	uint256	Uniform total fee in basis points	20 (0.20%)
protocolFeeCollector	address	Address that receives protocol fees	deployer

Constant: MAX_BPS = 10_000 (100%).

There is no maker/taker distinction. For buy-vs-sell-token matches, the total fee is split across buyer and seller; the seller side receives the rounding-up half. For normal Bid/Ask matches, the buyer-side locked fee funds the protocol fee.

Calculation Functions

calculateFee(amount)

Returns the total fee for a given filled collateral amount.

Formula: fee = amount * feeBps / 10_000

calculateHalfFee(amount)

Returns ceil(calculateFee(amount) / 2). BatchAuction uses this as the sell-side fee when a token/position seller receives a payout.

calculateOtherHalfFee(amount)

Returns calculateFee(amount) - calculateHalfFee(amount). BatchAuction uses this for the buyer side in buy-vs-sell-token matches.

Admin Functions

All admin functions require DEFAULT_ADMIN_ROLE.

setFeeBps(_feeBps)

Updates the uniform fee. Reverts if _feeBps > MAX_BPS.

setProtocolFeeCollector(_collector)

Updates the protocol fee collector address. Reverts if _collector is the zero address.

Events

Event	Parameters	Description
FeeBpsUpdated	uint256 feeBps	Emitted when fee changes
ProtocolFeeCollectorUpdated	address indexed collector	Emitted when fee collector changes

Example

With feeBps = 20:

• Filled collateral: 100 USDT

• Total fee: 100 * 20 / 10000 = 0.20 USDT

• Split fee: 0.10 USDT / 0.10 USDT before integer rounding

• Recipient: protocol fee collector