These Guidelines provide further detail on the parameters that trading venues should consider for the calibration of their circuit breakers, considering as such not only trading halts but also order price collars. The Guidelines also establish that trading venues should immediately make public the activation of a trading halt, the type of trading halt, the trading phase in which it was triggered, the eventual extension and the end of the halt.
The Guidelines are addressed to trading venues that allow or enable algorithmic trading on their systems and to national competent authorities (NCAs) with the aim to ensure consistent application of MiFID II.
NCAs to which these Guidelines apply must notify ESMA whether they comply or intend to comply with the Guidelines, within two months of the date of publication by ESMA of the Guidelines in all EU official languages.
The ESMA statement and related information can be found here.