What is an OCO order?

An OCO order (One Cancels the Other or OCO orders) represents two ordinary pending orders (for example, one of them is a deferred limit while the other is a deferred stop) that are interconnected by the mutual cancelation function. This means that if one of the orders is filled the other is automatically deleted by the system. Deferred OCO orders can be issued on the ATAS trading platform through the SMART DOM or through the Cart Trader module on the chart.

IMPORTANT:

• Most order routing systems do not support OCO order bundling; therefore, they are stored on the client side. This means that the correct operation of OCO bundles requires the ATAS platform to be launched and the account to be connected!
• Currently server placement of orders through the ATAS platform is supported only for CQG, IB, and ATAS SIM accounts.

You can see the comparative table of supported accounts here.