Meaning
It reads like legal boilerplate, but it is an execution rule in disguise. Translation: if the broker decides a fill was based on an ‘obvious’ pricing error (off-market tick, bad quote, system glitch), they may cancel or adjust the trade after the fact.
Why it exists
Upstream feeds do print bad ticks. In fast markets, those ticks can trigger stops, take-profits, or entries. The broker doesn’t want to warehouse the risk of a bad quote, so the contract often allows them to unwind ‘erroneous’ executions.
How it hurts
- ‘Too good to be true’ fills can be reversed days later.
- Stops/TPs may trigger on a spike that the broker later calls ‘off-market’.
- Your P&L becomes provisional when the market is chaotic.
How to respond
- Treat extreme spike fills as provisional until the dust settles.
- When you trade around releases, reduce size and avoid relying on one-tick precision.
- Keep documentation: screenshots of quotes/spread around the event window, platform logs (if available) and any error messages, a note of the session and whether an event/rollover was in play. If you dispute, ask for the broker’s tick history and error policy reference.
Red flag
If ‘manifest error’ is used frequently or inconsistently, your venue may be filtering outcomes in a way that damages trust. The solution is usually: trade different windows or change venue.
Notes
Plain English: brokers reserve the right to correct trades executed on clearly erroneous prices (bad ticks, feed outages, fat-finger prints).
Practical implication: if your “edge” relies on catching anomalies, you’re playing in a zone where reversals are possible.
Survival rule: if your entire edge is ‘catching spikes,’ you are building a strategy that the contract can legally unwind.