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05 June 2008

Service Announcement - Reminder

Performance Channels – Production Launch

The purpose of this Service Announcement is to remind you that the Performance Channels production service will be launched on Infolect on Monday 9 June 2008.

From this date those Extranex 100mb customers that have successfully completed the mandatory testing requirements, specifically a High Volumes Test and participation in a Dress Rehearsal weekend will be able to receive the new service in production.

Ahead of the go-live weekend the Exchange is currently disseminating idle polls on the Performance Channel multicast groups. This is to allow those customers going live with the service from Day 1 to reconfirm their configuration.

Documentation Update

Ahead of the launch of the new service, the Performance Channels Service and Technical Description has been updated. The latest version of the document is available from the Performance Channels section of the Exchange’s website at the following address:

www.londonstockexchange.com/performancechannels

Decommissioning of P03

Following the launch of the full service the current P03 Performance Channel Pilot service will be decommissioned on Friday 13 June 2008.

Performance Channels allow performance focused clients to receive 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.

More information on Performance Channels is available on the Exchange’s website at the following address:

www.londonstockexchange/performancechannels

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 the following address:

www.londonstockexchange.com/techlib

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

Service Announcement (Live) 41/08

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