What brokers mean when they say latency arbitrage

[Fairman]

What brokers mean when they say latency arbitrage

The term appears in client agreements and warning emails, and it is rarely defined well. In plain terms, latency arbitrage exploits a delay between a broker's price and the market's price. A trader with a faster feed sees the market move before the broker's quote updates, and trades at the stale price.

Brokers dislike it, because the trader wins at the broker's expense with almost no risk. Many respond with last look, slippage rules, or account restrictions.

The trouble for ordinary scalpers is that the label can be applied broadly. A trader with a fast connection and a quick strategy may be accused of it, even without any intent. Profits can be cancelled or the account closed.

The line between fast scalping and arbitrage is blurry, and brokers define it themselves.

It helps to read what the agreement says about prohibited strategies, and to ask for a clear definition in writing. A broker that cannot explain what counts as abusive is a broker that can call anything abusive.

A defence that works is documenting the strategy and its edge in writing: where the signals come from, why they are not based on stale quotes, and how entries are timed. If a broker accuses the account of abuse, a clear explanation and records of the logic carry weight.

Has a broker ever raised the term with an account, and how was it resolved?