# Commission Regulation (EC) No 1287/2006 of 10 August 2006 implementing Directive 2004/39/EC of the European Parliament and of the Council as regards record-keeping obligations for investment firms, transaction reporting, market transparency, admission of financial instruments to trading, and defined terms for the purposes of that Directive (Text with EEA relevance), Division: Table 1

Extent: E+W+S+N.I.

Information to be made public in accordance with Article 17
Type of system
Description of system
Summary of information to be made public, in accordance with Article 17
Continuous auction order book trading system
A system that by means of an order book and a trading algorithm operated without human intervention matches sell orders with matching buy orders on the basis of the best available price on a continuous basis.
The aggregate number of orders and the shares they represent at each price level, for at least the five best bid and offer price levels.
Quote-driven trading system
A system where transactions are concluded on the basis of firm quotes that are continuously made available to participants, which requires the market makers to maintain quotes in a size that balances the needs of members and participants to deal in a commercial size and the risk to which the market maker exposes itself.
The best bid and offer by price of each market maker in that share, together with the volumes attaching to those prices.
Periodic auction trading system
A system that matches orders on the basis of a periodic auction and a trading algorithm operated without human intervention.
The price at which the auction trading system would best satisfy its trading algorithm and the volume that would potentially be executable at that price.
Trading system not covered by first three rows
A hybrid system falling into two or more of the first three rows or a system where the price determination process is of a different nature than that applicable to the types of system covered by first three rows.
Adequate information as to the level of orders or quotes and of trading interest; in particular, the five best bid and offer price levels and/or two-way quotes of each market maker in the share, if the characteristics of the price discovery mechanism so permit.

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Source: https://www.legislation.gov.uk/eur/2006/1287/annex/II/division/1 (the official version)
Page: https://openlegislation.uk/eu-regulation-2006-1287/annex-II/division-1
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.