What it is
An iceberg order is a limit order that shows only a small part of its total size. The rest stays hidden and is refilled in small clips as the visible part gets filled, so the queue at that price looks about the same size again and again. The goal is to work a large position without advertising size to everyone reading the book. Traders call it an iceberg because only the tip shows.
In futures, this is a behavioral description, not a field in the data. Exchange order-by-order feeds are anonymous, so nobody can point at an order and call it an iceberg. What you get is a footprint: the price keeps trading, displayed size keeps coming back, and price barely moves while it happens.
- Small visible clip, much larger hidden size
- Refills after fills instead of showing everything at once
- The intent is to hide size and reduce market impact
What it looks like in order-by-order data
Order-by-order data, often called L3, records every exchange-visible order from insert, modify and cancel through to execution, rather than a snapshot of resting size. An iceberg leaves a rhythm in that stream. A level keeps printing trades, yet the displayed size does not shrink. New small orders appear at the same price and side shortly after each fill, similar in size and spacing, as if one process is repeating itself rather than many traders acting independently.
To spot iceberg orders in futures, compare trades against the book and ask whether the liquidity at that price is being replaced. One large resting order that fills and disappears is a different event from a level that keeps repairing itself. Absorption, heavy trading that does not move price, often appears alongside, but absorption is a price-response read while an iceberg is a refill read. Neither proves the other.
- Trades print, displayed size stays flat
- Fresh same-price orders right after fills
- The level gets hit repeatedly without price being pushed away
Common misconceptions and limits
The first misconception is certainty. Iceberg order detection is probabilistic. The hidden portion is never published, the true total is unknown, and the refills may come from several participants, from market makers managing inventory, or from algos that simply like that price. A level that refills a few times and then stops may have been an iceberg that finished, a trader who changed their mind, or liquidity that was pulled rather than filled.
The second misconception is treating displayed size as real supply. Depth only ever shows the tip. Third, icebergs can be cancelled or repriced, so behavior that looked persistent ends without warning. And because the feed is anonymous and covers only what the exchange sees, orders resting elsewhere are outside the picture.
Honest framing: iceberg order trading means reading a footprint and weighing alternatives, not confirming a hidden order. An iceberg order indicator that claims confirmation is overselling what the data can support.
What the GC research says
TradeWhy research on COMEX gold futures (GC), data through 2026-08-31, tested whether pre-touch cancel signals and post-touch refill ratios gave a stable read on this kind of hidden liquidity. The result was no stable signal, and the item is graded disproven, meaning independent replication did not pass or the finding was withdrawn. This approach did not hold up in the GC data.
So a refill ratio is not a reliable iceberg detector in GC. Scope matters: this applies to COMEX gold futures (GC) only, data through 2026-08-31, and does not generalize to other products or markets.
How to see it in TradeWhy
TradeWhy is an AI market-intent analysis and strategy validation tool for CME Group futures day traders, starting with COMEX gold (GC) and CME Nasdaq (NQ). It puts real-time macro information, price response and L3 order-by-order behavior side by side to explain what the dominant force is doing. L3 records each exchange-visible order from insert, modify and cancel through to execution, which helps you judge whether orders really want to trade, whether liquidity is pulling back, whether size keeps refilling after fills, and whether heavy volume actually moves price.
On iceberg orders, TradeWhy works from those same anonymous order-level events: no trader identities, and nothing outside the exchange. Hidden liquidity can only be inferred from refills and the trade path, never treated as fact.
TradeWhy does not give buy or sell advice and makes no promises about returns; the trading decision is the user's. Recurring behavior can be organized into strategies and, after historical and forward validation, added to a strategy portfolio.
FAQ
What is an iceberg order?
It is a large order that only displays a small clip at a price while the rest stays hidden, refilling a small piece each time the visible part is filled. It is a description of behavior, not a label in the data, so it can only be inferred from refills.
What does an iceberg order example look like?
A level keeps trading, the displayed size does not shrink, and small new orders appear at the same price and side right after each fill. There is no published quantity attached to it; you only see the pattern repeat.
How do you spot iceberg orders in futures?
Look for trades printing at one price without the displayed size dropping, and for similar-size orders arriving at that same level after each fill. These are clues, not proof, and they fade the moment the refills stop.
Iceberg order vs basket order?
They describe different things: a basket order groups several legs or instruments sent together as one instruction, while an iceberg hides the size of a single order in one instrument. The iceberg question is about hidden depth, not about grouping instruments.
Can you see the hidden quantity of an iceberg order?
No. Exchanges publish anonymous order-level events without the hidden total, so the true size can only be estimated from how often a level refills and how trades behave around it.
Written by AI from TradeWhy's metric definitions, research findings and published product statements, then rule-checked. Research figures come from TradeWhy's study of COMEX gold futures (GC), data through 2026-08-31, and apply to GC only. Analysis only, not investment advice.