When you place an OCO order, once the price triggers and one leg gets filled, the other leg becomes automatically invalid. This invalid pending order will never be automatically "reactivated" by the system — it is canceled directly, and will not stay in the order queue as an unfilled pending status.
The world's largest cryptocurrency exchange by trading volume,leading in security and liquidity.
New user benefit: Enjoy 20% off trading fees upon registration!
OCO "Auto-Cancellation" Logic
OCO (One-Cancels-the-Other) is essentially a pre-set instruction that the system executes for you. When you place a limit order and a stop-loss order at the same time, whichever price level the market hits first, the other order gets invalidated immediately. The key point here is: it is not "paused", it is fully invalidated.
Limit order gets filled first: The system confirms your preset target is achieved, so the corresponding stop-loss order is no longer needed, and will be canceled immediately.
Stop-loss order gets triggered first: The system closes your position to stop loss, and the upper limit order will also be canceled synchronously, it will not stay in the order list waiting to be filled if the market reverses later.
Why Does One Side of the OCO Order Get Canceled
Based on the common design mechanism of trading platforms, there are two main possible conditions that trigger single-side cancellation:
Scenario A: Extreme price fluctuation. The market surges or crashes sharply in an instant, triggering both upper and lower preset price levels at the same time. OCO follows the "first hit, first cancel" rule: the leg that the market touches first gets the fill eligibility, the other leg is invalidated immediately.
Scenario B: Manual intervention. You manually cancel one of the two pending legs of the OCO order during your holding period. The trigger rule is: as long as one leg is manually canceled, the other leg will also be automatically revoked by the system, because OCO logic requires "both legs exist, or neither exists".
The world's largest cryptocurrency exchange by trading volume,leading in security and liquidity.
New user benefit: Enjoy 20% off trading fees upon registration!
Status and Risks of the Remaining Leg After One Side Is Canceled
After one side of the order is canceled, the other leg's status is marked as "Canceled" permanently. It will not re-enter the pending order queue, nor will it reappear when you refresh the page next time.
There is an easily overlooked risk point: if you originally rely on the stop-loss order to prevent downside risks, and the limit order gets filled first leading to the stop-loss order being canceled, your position becomes an "unhedged long" or "unhedged short" state, losing the protection of automatic risk control. During periods of extreme market volatility, this state may expose you to larger than expected losses.
Verification method after operation: After any leg is canceled or triggered, check the "Open Orders" list. If you can no longer find the other leg in the list, it has been successfully auto-canceled by the system. If you still need a pending order at that original price level, you have to place a new order manually.
