Iceberg orders, hidden orders and spoofing awareness

Not everything in the book is what it appears. Two phenomena distort the DOM in opposite ways: hidden liquidity (real size you cannot see) and spoofing (visible size that is not real).

Iceberg and hidden orders

An iceberg order shows only a small "tip" on the book while a much larger quantity sits hidden behind it; as the visible piece fills, it automatically reloads from the hidden reserve. Hidden orders show no visible size at all and only reveal themselves when they trade.

Why participants use them: to work large size without telegraphing intent (recall the slicing problem).

How they appear on the tape: a price level that keeps trading more than the book ever showed as available — you see far more volume execute at a price than the displayed size could account for. That persistent reloading is often the footprint of an iceberg, and a classic source of absorption.

Spoofing — and the legal line

Spoofing is placing large visible orders with no intent to execute them, purely to create a false impression of supply or demand, then cancelling before they fill. It can bait other participants into reacting.

Be clear: spoofing is illegal market manipulation on regulated exchanges and has been prosecuted with large fines and prison sentences. We cover it only so you are not deceived by it — never as a tactic. Placing and cancelling orders to mislead is a crime; do not do it.

What awareness changes in your reading

• A "wall" of resting size is not reliable support/resistance — it can be pulled or be a spoof. Weight the tape (what actually trades) over the book (what merely appears).
• Persistent execution beyond visible size = likely hidden/iceberg liquidity = real participant = meaningful.
• Size that vanishes the instant price approaches = treat as noise, possibly a spoof.

The honest synthesis: the visible book is the least trustworthy layer. Executions don't lie; resting intentions do.