Order book

The order book is the live list of all outstanding buy and sell orders for an instrument, arranged by price, that a trading venue displays to participants. It is the primary public signal of where supply and demand sit at any moment, which is precisely why placing insincere orders in it is a manipulation technique.

market microstructure · updated 2026-09-08

Where does order book come up?

This term is used in the following manipulation techniques, each explained in full on its own page.

• Spoofing — Spoofing is placing orders a trader intends to cancel before execution, to create a false impression of supply or demand and move the price toward a smaller genuine order on the other side.
• Layering — Layering is placing multiple orders at several consecutive price levels with no intention of trading them, building an apparent wall of depth that pushes the price toward a genuine order on the other side.

Enforcement actions involving these techniques

See also

• Bid — A bid is an order to buy a stated quantity at a stated price or better. The highest bid in the book is the best bid, and it is one…
• Ask — An ask, also called an offer, is an order to sell a stated quantity at a stated price or better. The lowest ask is the best offer.…
• Depth — Depth is the total quantity available at each price level in the order book. Deep books absorb large orders with little price move…
• Limit order — A limit order is an instruction to trade only at a specified price or better. It rests in the order book until it is filled, cance…

Terms that refer here

Bid · Book imbalance · Dark pool · Depth · Fill · Iceberg order · Limit order · Lit market

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