[ESMA 70-872942901-38 MiFID II MiFIR market structures Q&A, Q&A 3.21]

Trading venues enabling or allowing algorithmic trading through their systems shall be able to cancel or revoke transactions in case of malfunctioning of the trading venue’s mechanisms to manage volatility or of the trading system in the context of disorderly trading conditions, according to Article 18 of RTS 7.

However, Article 47(1)(d) of MiFID II also establishes the general organisational requirement for all trading venues “to have transparent and non-discriminatory rules and procedures that provide for fair and orderly trading and establish objective criteria for the efficient execution of orders”. Therefore, the rulebook of a trading venue may foresee other exceptional situations in which transactions might be cancelled provided that those situations are transparent and non-discriminatory.