(6)Regulation (EU) 2024/791 amended Article 31 of Regulation (EU) No 600/2014 by expanding, beyond portfolio compression services, the scope of post-trade risk reduction (‘PTRR’) services that form and establish transactions in OTC derivatives, which are exempt from requirements of pre- and post-trade transparency, the trading obligation and requirements of best execution. Regulation (EU) 2024/791 empowered the Commission to specify what constitutes PTRR services for the purposes of Article 31(1) of Regulation (EU) No 600/2014 and the transactions to be recorded by PTRR services providers pursuant to Article 31(4) of the latter Regulation. In order for transactions in OTC derivatives to be exempt from requirements of pre- and post-trade transparency, the trading obligation and requirements of best execution, PTRR services that form and establish those transactions should comply with a number of conditions. They should be provided by a third-party service provider on the basis of non-discretionary rules that are set in advance; the participants in the PTRR exercise should not be able to choose which trades to execute; PTRR services should have the purpose of achieving a reduction of risk in each of the portfolios submitted to the PTRR exercise by the counterparties to the derivative transaction or by an agent acting on their behalf; they should be market-risk neutral; and transactions resulting from the PTRR exercise should not contribute to price formation. Limited risk tolerances can be set by the counterparties to the derivative transaction, provided that market risk neutrality is overall ensured. To ensure legal clarity, Delegated Regulation (EU) 2017/567 should be amended to specify that, for the purposes of Article 31(1) of Regulation (EU) No 600/2014, PTRR services include compression, rebalancing and basis risk optimisation.