10 Paternoster Square
London EC4M 7LS
Telephone +44 (0)20 7797 1000

10 July 2007

Service Announcement

Launch of Performance Channel Service

The London Stock Exchange is pleased to announce further details on the launch of the full Performance Channel service in production.

Performance Channels allow performance focused clients to receive Infolect real-time data with higher throttle settings than Service Channels currently allow, in order to reduce any data delivery latency that may be incurred during high spikes in trading activity.

The full Performance Channel service is scheduled for launch in Q1 2008. The go-live date of the service will be communicated by Service Announcement in due course.

To ensure Performance Channel data can be delivered unshaped and without delay customers who wish to subscribe to the new service will be required to upgrade to an Extranex 100Mb connection. Customers who submit their Extranex 100Mb orders by 31 August 2007 will have the standard installation costs waived. Any orders submitted after this date will be subject to the standard installation costs. Please note that orders received after 31 August 2007 may not be completed in time for Performance Channel go-live.

Further details on the Performance Channel service are available from the Exchange’s website at.

Details on the technical structure and testing requirements for Performance Channels will be confirmed shortly in an update Service and Technical Description document.

For further information on the service, including details on pricing, please contact your Primary Account Manager.

Performance Channel Pilot

The Performance Channels pilot service is available now to all customers connected to the Exchange using an Extranex 10mb connection. As part of the pilot phase, the UK Level 2 Service Channel (S03) is offered as a Performance Channel (P03) for a free trial period (providing you are an existing S03 subscriber).

More information on the Pilot serviceis available in the “Performance Channel Pilot Service - Service and Technical Description” document, available on the Exchange’s website at the following location:

If you would like to participate in the Pilot please contact your Technical Account Manager.

Additional Information

If you have any queries or require further information please contact your Technical Account Manager or the Technical Information Desk on 020 7797 3939 (STX 33939).

An archive of previously issued service announcements is available on the Exchange’s website at:

If you would like to amend or add further recipients of service announcements, please send the revised email contact details to:

Service Announcement (Live) 51/07

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