RNS Number:5210Q
Marconi Corporation PLC
03 October 2003


                                                                Press enquiries:
                     Joe Kelly, tel: 0207 306 1771; email: joe.kelly@marconi.com
                   David Beck, tel: 0207 306 1490; email: david.beck@marconi.com

                                                             Investor enquiries:
             Heather Green, tel: 0207 306 1735; email: heather.green@marconi.com


            NOTICE OF PARTIAL REDEMPTION OF MARCONI CORPORATION PLC
                  10% GUARANTEED JUNIOR SECURED NOTES DUE 2008
                 CUSIP No. : G58129AD2; ISIN No. : XS0166109768
 $28.9m (#17.3m) Junior Notes to be redeemed at 110%, reducing principal amount
                      of Junior Notes to $288.7m (#172.9m)

London - 3 October 2003 - Marconi Corporation plc (London: MONI and Nasdaq:
MRCIY) today gave notice to the owners of its 10 per cent guaranteed Junior
Secured Notes, due 2008 (the Securities) pursuant to Section 3.02 of the
Indenture dated as of 19 May 2003 (the Indenture) made between the Company, the
guarantors named therein and JP Morgan Chase Bank (the Trustee) that pursuant to
Section 3.08 of the Indenture $28,916,278 aggregate principal amount of
Securities (the Redemption Securities) will be redeemed on 17 October 2003 (the
Redemption Date).

The redemption price (the Redemption Price) shall be 110.0% of the principal
amount of the Redemption Securities redeemed plus 77 days accrued interest to
the Redemption Date.

In line with the mechanism used for the previous partial redemption of the
Junior Secured Notes, which took effect on 30 September 2003, a pool factor will
be applied to every holding. Further details of the pool factor to be applied
from the Redemption Date will be announced once the pool factor has been
confirmed by the Registrar.

This mandatory partial redemption has primarily resulted from the previously
disclosed sale of the Group's stake in Bookham Technology plc.
The paying agent with respect to the Redemption Securities is:

                        The Bank of New York
                        One Canada Square
                        London E14 5AL
                        England
                        Attention: Corporate Trust Office

Any queries in respect of payment, pool factor or related matters should be
directed to Emma Wilkes at Bank of New York on (+44) 20 7964 7662, who are the
Registrar, the Depositary and the Paying Agent.

On the Redemption Date, the Redemption Price, together with accrued interest and
any Additional Amounts, will become due and payable. Unless the Company defaults
in making the redemption payment, the Redemption Securities shall cease to bear
interest from and after the Redemption Date. The Redemption Securities will be
cancelled following redemption by the Company.

ENDS/...


About Marconi Corporation plc

Marconi Corporation plc is a global telecommunications equipment, services and
solutions company. The company's core business is the provision of innovative
and reliable optical networks, broadband routing and switching and broadband
access technologies and services. The company's customer base includes many of
the world's largest telecommunications operators.
The company is listed on the London Stock Exchange (MONI) and on Nasdaq (MRCIY).
Additional information about Marconi Corporation can be found at
www.marconi.com.

Copyright (c) 2003 Marconi Corporation plc. All rights reserved. All brands or
product names are trademarks of their respective holders.

This Press Release contains certain statements that are not historical facts,
including statements about Marconi's expectations and beliefs and statements
with respect to its business plan and other objectives. Such statements are
forward-looking statements. These statements typically contain words such as
"intends", "expects", "anticipates", "estimates" and words of similar import.
Undue reliance should not be placed on such statements, which are based on
Marconi's current plans, estimates, projections and assumptions. By their
nature, forward-looking statements involve risk and uncertainty because they
relate to events and depend on circumstances which may occur in the future.
There are a number of factors that could cause actual results and developments
to differ materially from those expressed or implied by such forward-looking
statements. These factors include, but are not limited to future revenues being
lower than expected; increasing competitive pressures within the industry;
general economic conditions or conditions affecting the relevant industries,
both domestically and internationally, being less favourable than expected.
Marconi has identified certain important factors that may cause actual results
to differ materially from those contained in these forward-looking statements as
described in Marconi's Form 20-F annual report and Form 6-K reports filed with
the US Securities and Exchange Commission. Marconi disclaims any obligation to
publicly update or revise these forward-looking statements, whether to reflect
new information or future events or circumstances or otherwise.



                      This information is provided by RNS
            The company news service from the London Stock Exchange

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