RNS Number:0503U
Marconi Corporation PLC
09 January 2004


                                                                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

                               PARTIAL REDEMPTION
                           OF MARCONI CORPORATION PLC
                  10% GUARANTEED JUNIOR SECURED NOTES DUE 2008
                             CUSIP No. : G58129AD2
                            ISIN No. : XS0166109768

      $51.6 million Junior Notes to be redeemed at 110% on 12 January 2004

London - 9 January 2004 - Marconi Corporation plc (London: MONI and Nasdaq:
MRCIY) today confirms to the owners of its 10 per cent guaranteed Junior Secured
Notes, due 2008 (the Securities) the parameters of the redemption of $51,612,793
aggregate principal amount of Securities (the Redemption Securities) that was
announced on 23 December 2003.

The Record Date shall be the close of business in London on 9 January 2004. The
Redemption Date, as previously announced, shall be on 12 January 2004.

In line with the mechanism used for the previous partial redemption of the
Junior Secured Notes which took effect on 2 December 2003, an additional pool
factor of 10.6006895% will be applied to every holding, calculated with
reference to the original issue amount of $486,881,472. As at 12 January 2004
the total pool factor, including the previous redemptions effective on 31 July,
30 September, 17 October and 2 December 2003, will be 57.0274167%, calculated
with reference to the original issue amount of $486,881,472.

On the Redemption Date, the Redemption Price, together with accrued interest,
will become due and payable. The Redemption Securities shall cease to bear
interest from and after the Redemption Date.

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.

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) 2004 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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