155.EC law requires each member State to nominate or create a competent authority to maintain an official list of securities, to regulate the admission of securities to the Official List, and to monitor issuers’ adherence to the listing rules (as explained below) thereafter.  In the United Kingdom these functions are exercised by the Authority following the coming into force of the Official Listing of Securities (Change of Competent Authority) Regulations 2000 (SI 2000/968), the competent authority function was exercised by the London Stock Exchange.  The provisions of this Part implement these requirements of EC directives.  These provisions replace those in Part IV of the FS Act 1986.
156.There is no requirement for issuers of securities, for example companies issuing new shares, to apply for admission to the official list.  However, admission to the official list signals that certain standards regarding the financial status and history of the company have been met; that adequate information about a security has been made available to investors at the time of application; and that information about the performance and plans of the issuer will continue to be made available on a continuing basis so long as the company has securities listed on the official list.
157.In carrying out its functions, the competent authority makes rules which govern the admission of securities to listing, the continuing obligations of issuers, the enforcement of those obligations and the suspension and cancellation of listing.  These rules are collectively known as “listing rules”, which have been published by the competent authority in the “yellow book”.  The competent authority also has a role in scrutinizing prospectuses and circulars where there is no application for admission to the official list.
Commentary on Sections Part Vi: Official Listing