# OpusUsers OpusAMM services two user types: Liquidity Providers (LPs) and Liquidity Takers (LTs). ## Liquidity Providers LPs are the collateral providers for Opus’ ecosystem and the liquidity that backs OpusAMM. As passive market makers, LPs permission OpusARM to make prices and manage resulting portfolio risks on their behalf. LPs deposit their stablecoins (ex. USDC) into an OpusAMM liquidity pool and earn returns through bid-offer spreads, trading fees, and profitable management of the liquidity pool’s positions. Specifically, LPs will transfer stablecoins from their personal wallet to OpusTreasury where it will be used as collateral to face LT trading activity. In return, LPs will receive liquidity pool units (LPU) which reflect their pool percentage ownership. The net asset value of an LPU (LPU NAV) will be managed by OpusTreasury and calculated as follows: $$ LPU\_{nav} = \text{Liquidity Pool Value} / \text{Total LPU Units} $$ LPs will be able to withdraw their liquidity at LPU NAV’s end-of-day price on a T+1 basis. ## Liquidity Takers LTs are independent traders and either option sellers or buyers. ### LT Option Sellers Opus’ flexible margin calculator (OpusFlex) improves capital and trading efficiencies by allowing LTs to sell options on margin. LTs will deposit margin collateral into their OpusTreasury account which is continuously marked to market and reflected in their respective account dashboards. LT positions are auto-liquidated by OpusTreasury if a predetermined price level trades before additional capital is deposited. The onus is on the LT to track their margin collateral requirements. If the LT wants to avoid a close liquidation price level, they can choose to deposit more collateral, raise their margin amount, or both. OpusFlex calculators are available to work with on a bespoke basis within an LT’s personal dashboard. ### LT Option Buyers Option buyers must deposit the full premium for each option purchased into OpusTreasury. Long options are netted against short option positions to realize collateral management efficiency. All option contracts are auto exercised by OpusTreasury and USDC settled. There are no limitations to being an LP or an LT or both simultaneously.