A passive liquidity order (PL order/ PLO) that is, once entered, it will not interact with an incoming order that has an immediate-or-cancel (IOC) time in force (TIF) condition or is an intermarket sweep order (ISO), but will otherwise retain its standing in execution/ fill priority among passive liquidity orders.

An incoming passive select order that is marketable will be filled against all available contra-side interest without restrictions. However, any remaining part of this order, that goes unmatched, will be subject to any restrictions. The entry of passive liquidity select orders may be suspended by a broker, with a notice of the effect to clients (holders of exchange-traded products/ ETPs)- and any open such orders will be cancelled.