Glossary
Matched orders
Matched orders are buy and sell orders entered at or nearly at the same time, with very similar quantity and price, by the same party or by parties acting together. UK market-abuse rules list "improper matched orders" as a sign of manipulation (Delegated Regulation 2016/522, Annex II).
Why it matters for brokers and payment firms
On a broker's book, matched orders between linked accounts are the mechanical signature of wash trading, IB rebate farming and hedged bonus accounts. Detection pairs opposite trades by symbol, size and time.