17 October 2008
Service Announcement
TradElectTM Production and CDS
Advance Notification:
- Introduction of minimum order size for 60 AIM Securities on SETS
- Minor sector changes in SETS and International Order Book
The purpose of this Service Announcement is to provide notification of the introduction of a minimum order size in a dedicated sector within the AIM SETS segment (AMSM) from 3 November 2008.
Unconnected with this initiative, notice is also given of the introduction of a new sector in SETS trading segment SSMU and changes to the description of six sectors within trading segment IOBU.
Minimum order size for 60 AIM Securities on SETS
As part of an ongoing market consultation, the Exchange has been undertaking a review of how to improve liquidity and stability within smaller securities. This has seen the introduction of a specific smaller company tariff and revised market maker obligations during September 2008. Later this year PSQ Analytics, a new smaller companies equity research product will also be launched.
As a further step it is now planned to introduce a minimum order size of 50% of Exchange Market Size (EMS) in 60 securities traded within the AMSM segment. The securities concerned are lesser traded AIM securities on SETS that are not part of the FTSE AIM 50 Index or reserve list
To allow easy identification the securities that have a minimum order size will be moved to sector ASM6, which is currently unused and will be revised as below.
Trading Service / Segment Code / Segment Description / Sector Code / Revised Sector DescriptionSETS / AMSM / AIM ON SETS / ASM6 / MIN ODR SIZE 50% EMS–15% MX SP
Sector Code / Revised Minimum Order Size / Revised Iceberg peak / Revised Max Spread % / Revised Max Spread floor £/€/$
ASM6 / 50% of security’s EMS / 50% of security’s EMS / 15 / 0.05
Appendix 1 sets out the 60 securities that will be included in the initiative. The concept of a minimum order size and the securities to be included will be kept under review.
New trading sector in segment SSMU
To allow for certain securities within the SETS London Secondary Listed segment (SSMU) to have a wider maximum spread regime, a new sector (SMEV) is being created. With the exception of the specific fields identified below, the parameters and trading period rules will be identical to the existing SSMU sector SMEU. Securities to be added to the new sector will be notified in the standard way through the Exchange’s reference data service, Datasync.
SETS / SSMU / SETS - London Secondary Listed / SMEV / LON SEC LSTD – 10% MAX SP
Sector Code / Max Spread % / Revised Max Spread floor £/€/$
SMEV / 10 / 0.03
Amendment of International Order Book Sectors
To ensure clearer categorisation of the Exchange’s securities on the International Order Book, the sector description changes below will take place. Also detailed is an amendment to the dynamic price monitoring threshold for one of the sectors concerned.
Any securities to be moved following these changes will be notified in the standard way through the Exchange’s reference data service, Datasync.
International Order Book / IOBU / IELW / IOB ATT NON LISTED SECS .
IEHH / IOB EU LISTED SECS
INUH / IOB ATT SECS HGH PRCD.
INUL / IOB ATT SECS LOW PRCD.
INUU / IOB ATT SECS AUC.ONLY TDG.1
INUA / IOB ATT SECS AUC.ONLY TDG.
Sector Code / Revised Dynamic Price Monitoring %
IELW / 10
Proposed schedule for introduction of all changes
CDS Start of trading Monday 27 October 2008
TradElect™ Production Start of trading Monday 3 November 2008
Administration
CDS
For CDS, customers are advised to subscribe to the Reference Data Changes on Friday 24 October 2008 or the Full Reference Data Download Service on Monday 27 October 2008. A reduced number of instruments will be available for testing in CDS segment ASM6.
TradElect Production
For Production, customers are advised to subscribe to the Reference Data Changes service on Friday 31 October 2008 or the Full Reference Data Download Service on Monday 3 November 2008.
The TradElect Parameters document will be updated immediately before the above changes are implemented and it can be accessed as a download from the following link:
Should you wish to discuss the contents of this Service Announcement further, including specific feedback about stocks with a minimum order size, please contact either your account manager or Demos Skordis on
+44 (0)20 7797 4513.
An archive of previously issued announcements is available in the “Technical Library” section of the Exchange's corporate website
More information on Datasync, including how to subscribe, is available in the Info Products section of the Exchange’s corporate website
Service Announcement (LIVE) 113/08
London Stock Exchange plc Registered in EnglandWales No 2075721