The overhaul of transaction reporting under MiFID II continues unabated in the latest ESMA drafts, with new obligations and data changes still being introduced. Aimed at improving the quality of data for market abuse investigation, ESMA has introduced a new requirement for transaction reports to be made available to regulators in a common XML template in accordance with ISO 20022 methodology. Currently used mainly for payments and post-trade financial messages, this international standard has won ESMA's favour for its "flexibility to accommodate future developments". I'm not so sure, though, about its proposed use for trade publication, an altogether more real-time concern. Not least, there are issues around screen real estate and the use of text fields if there is a switch from the existing single character to the ISO's 4 character code for electronic messaging.
Elsewhere, looking down the revised list of 65 fields, ESMA's financial instrument identifier of choice seems to be the ISIN (International Securities Identification Number). Where one is supplied it looks like 15 other pieces of instrument information can be skipped on the report, which is some good news. Whether this will lead to ISINs being adopted for more instruments remains to be seen.