(12)In order to ensure that the exception to systematic internalisers obligations to execute the orders at the quoted prices at the time of reception of the order in accordance with Article 15(2) of Regulation (EU) No 600/2014 is limited to transactions which by their nature do not contribute to price formation, this Regulation further specifies exhaustively the conditions for what constitutes transactions in several securities as part of one transaction and orders subject to conditions other than the current market prices.