RNS Number:5062R
Marconi Corporation PLC
30 October 2003

JP Morgan Securities Ltd.
125 London Wall
London
EC2Y 5AJ

Direct Line 020 7325 4578
Fax: 020 7325 4179
Switchboard: 020 7325 1000


30 October 2003


Marconi Corporation Plc
4th Floor, Regents Place
338 Euston Road
London
NW1 3BT


Dear Sir,

Marconi Corporation Plc
S198 Companies Act 1985 Interest in Shares


J.P. Morgan Securities Ltd. hereby notifies you that it no longer has a
beneficial interest in the share capital of your company.


Yours faithfully,



Vanessa Hilborn
EMEA Compliance Department


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