Brokers role in the REMIT reporting framework appears somewhat complex. Let alone entirely different structuring of executing brokers and the clearing ones (where the clearing brokers have been placed - fundamentally - outside the REMIT market participants' scope), the reporting of life-cycle events with respect to trades executed with the broker's participation requires a careful reflection.
Another problematic case emerges when the firm has two different types of business - is an executing broker (exchange member) and is also an organised market place (it runs a broker platform). Recent updates to the ACER's reporting manuals offer some help while resolving these issues.