On 27 May 2019, the European Securities and Markets Authority (ESMA) published an updated opinion on calculating market size of ancillary activity under MiFID II.
The opinion, targeted at Member State national competent authorities, relates to Article 2(3) of Delegated Regulation 2017/592 which lays down the rules for calculating the overall market trading activity. The calculation of the overall market trading activity is necessary for the establishment of the size of trading activity per market participant which ultimately determines whether an activity is ancillary, and hence, whether a market participant falls within the scope of MiFID II.
Amongst other things, at section 4 of the opinion, ESMA provides estimates of the market size for various derivatives including metals, oil and gas.