(23)Annex I to Delegated Regulation (EU) 2017/587 sets out the types of trading systems and, for each system, a description of its main features and the information to be made public in accordance with Article 3 of Regulation (EU) No 600/2014. That Annex should be modified to specify that trading systems operated by means of an order book that only include market maker quotes and a trading algorithm operated without human intervention that matches incoming buy and sell orders with resting market maker quotes on the basis of the best available price on a continuous basis should be considered as continuous order book trading systems. Trading systems operated by means of an order book, where the quotes of the liquidity providers are confirmed before the potential execution of an incoming order, and a trading algorithm that matches incoming buy and sell orders with the confirmed quotes of the liquidity providers without human intervention on the basis of the best available price on a continuous basis should also be considered as continuous order book trading systems.