(4)In order to prevent market abuse, it is appropriate to set conditions regarding the purchase price and permitted daily volume of trading in own shares in buy-back programmes. To avoid circumvention of such conditions, the buy-back transactions should be carried out on a trading venue where the shares of the issuer are admitted to trading or traded. However, negotiated transactions that do not contribute to price formation could be used for the purpose of a buy-back programme and benefit from the exemption, provided that all the conditions referred to in Regulation (EU) No 596/2014 and this Regulation are met.