In simple terms
An iceberg order is normally a limit order that displays only a tranche of its total quantity in the book. When the visible portion executes, the system may expose another tranche according to the venue's rules.
How the term is used
The term describes quantity management, not an entirely invisible order. A native iceberg is managed by the market; a synthetic iceberg may be split and resubmitted by an external system. Refills, identifiers, and queue priority can therefore behave differently. Quantity reappearing at the same price is consistent with an iceberg, but it may also come from independent new orders.
For mechanics, priority, and edge cases, see Iceberg and reserve orders.
Limit
The book does not reveal total size, participant identity, or intent with certainty. An iceberg does not guarantee a fill, anonymity, lower market impact, or preservation of priority after every refill.
Sources
- CME Group, Market by Order (MBO) — FAQ — distinguishes MBO and MBP feeds, OrderID, PriorityID, and native or synthetic icebergs within CME Globex; these rules are not universal.
- CME Group, Display Quantity Order Overview — describes displayed quantity, time priority, fills, and replenishment for CME orders; it is venue-specific documentation.