(4)In order to enable cross-border searches and accurate search results, an OAM should use a unique identifier for each issuer of securities admitted to trading on a regulated market. Harmonisation of the unique identifiers used by OAMs should enable end users of the EEAP to identify more readily the issuers in respect of whom the end users seek information. Moreover, given the integration of financial markets at international level, the unique identifiers to be used by OAMs should be accepted internationally, be suitable to be assigned to any issuer, be consistent in time, have a limited financial impact on issuers and OAMs, and take into account future developments in this area. Therefore, OAMs should use legal entity identifiers as the unique identifier for issuers of securities admitted to trading on a regulated market.