ISDA, AFME and GFXD have sent a letter to the European Securities and Markets Authority (ESMA) laying out some key outstanding uncertainties in the Markets In Financial Instruments Regulation (MIFIR) post-trade transparency framework for investment firms from an over-the-counter derivatives perspective. This concerns are in addition to the uncertainty around the acceptable trading protocols for package orders containing a component subject to the trading obligation, and the territorial scope of MIFIR obligations, which ESMA are understood to be currently considering.