Blog / Rule explainer
Why a breach uses a composite mark
One exchange can print a wick the rest of the market never saw. The composite mark, degraded states and breach reviews keep it from failing you.
A breach ends an evaluation, so the price that decides it matters more than any other number on the platform. That price is the composite mark: built from the mark prices of Bybit and Hyperliquid, and recalculated as each venue updates.
One venue is not enough
Perpetual futures trade on many venues, and each has its own order book. A large order on one of them can push its price for a moment while the others stay put. If equity were measured on that venue alone, a trader could fail on a print that no other market confirmed.
When the venues disagree
When the two marks drift apart, or one stops updating, the symbol becomes degraded. New exposure on it is refused; you can still reduce or close. A floor crossed while a symbol is degraded does not end the account: the breach goes to review, positions stay open in reduce-only mode, and a person confirms or reverses it with the stored prices.
When there is no fresh price
If no venue sends a fresh price, trading on that symbol pauses and no breach is evaluated on it. It resumes when fresh prices return. A data outage never counts against you.
When many accounts breach at once
If an unusual number of accounts breach on the same symbol at the same moment, the engine treats it as a data problem first: new breaches on that symbol go to review until the prices are checked.
What fills use
The composite mark decides equity and breaches. Your orders still fill against the live Bybit order book, level by level, with the fees on the rules page. Every breach report stores the composite mark, each venue's price, your equity, the floor and the positions at that moment, so you can check the decision yourself.
Related
- Composite mark priceThe composite mark price combines the Bybit and Hyperliquid mark prices and decides equity and breaches, so one exchange cannot fail an account alone.
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