Quote stuffing

Definition

Every order, modification and cancellation is a message the exchange must process and usually publish. Quote stuffing floods that channel. The aim attributed to it is to delay other participants, whose market data or order acknowledgments arrive later while the flood is processed. In US futures, the CFTC's guidance on disruptive practices names overloading the quotation system of a registered entity as one of the forms of spoofing, which the Commodity Exchange Act prohibits when done with the intent to cancel the orders before execution.

What it looks like in market data

• Bursts of thousands of book updates at one or a few prices, with little net change in displayed size once the burst ends.
• Few or no trades during the burst: the messages are orders and cancellations, not executions.
• Growing latency in the feed: book updates and trades arriving later than usual, or out of step with each other.
• On a heatmap, a speckle of size appearing and disappearing, often too fast to be drawn at all.

A worked example

Over one second, a price level receives five thousand add and cancel messages for the same few contracts, and its displayed size ends where it began. No trade prints there. A snapshot-based feed that samples the book every 100 milliseconds shows ten states of that level, a small and possibly misleading fraction of what happened, while an order-by-order feed shows every message and may itself fall behind. Whether the burst came from a malfunctioning algorithm, an aggressive requoting strategy or deliberate stuffing cannot be read from the data.

Why it matters for order flow tools

The practical risk for a chart reader is data quality rather than the intent of others. A burst can delay the feed, make depth and trades drift apart in time, and make a displayed level unreliable for a few moments. Tools that coalesce book updates to the display rate, rather than drawing every message, stay usable; tools that report how late or out of order their data is let the reader know when to distrust the picture.

In Senzoukria

The heatmap's Liquidity lens publishes the limits of its own evidence. It measures the offset between the depth stream and the trade stream and shows it as a median in milliseconds, noting that no event is discarded for it. It counts depth snapshots that arrived older than the previous one on the same stream and were not applied, and trades that arrived out of order and were not counted at their level. Those counters describe the feed's condition; they do not attribute a cause.