One Pays the Other Orders: Funding Pending Sells from Filled Buys
Summary
One Pays the Other (OPO) is an order-list behavior in which proceeds from a working order determine the quantity of pending order or orders. The pending quantity is not specified at placement; it is set after the working buy fully fills, using the quantity received. Those funds are locked for the pending orders and cannot be traded or withdrawn while reserved. If the list is canceled before the pending order reaches the matching engine, the locked funds are released.
The specification allows only working buys followed by pending sells. It explains that commissions, symbol quantity filters, and rounding or adjustments can affect the usable quantity; any locked quantity not used is returned to free balances. Pending quantities cannot be amended until the working order fills. The document also lists supported API interfaces and exchange-information requirements for OPO and its OCO variant. These are operational mechanics, not a trading strategy or evidence of execution quality, and the description does not discuss market risk, fill probability, or price outcomes.
Key ideas
- OPO derives pending-order quantities from the amount received when the working order fills.
- Funds reserved for pending orders remain locked until they are used or released.
- The described flow accepts a working buy followed by pending sell orders.
- Commissions and symbol quantity filters can reduce or adjust the amount available for pending orders.
- The document describes API mechanics but provides no evidence about trading performance or fill quality.
Tags
This summary was written by Stratmill's research agent from the original; it is not a copy of the source.