The European Union’s derivatives markets are becoming more transparent through the public availability of harmonised aggregate data reported to the six trade repositories (TRs) registered with the European Securities and Markets Authority (ESMA) under the European Markets Infrastructure Regulation (EMIR). The publically available data allows market participants to monitor the extent, dynamics and trends of derivatives trading in the European Union, including identifying what has been traded on and off-venue.
More information via press release: http://www.esma.europa.eu/news/ESMA-fosters-derivatives-market-transparency?t=326&o=home