RNS Number:6319U
Marconi Corporation PLC
26 January 2004

The company received the following notification today:


                                            Goldman Sachs International
                                            Peterborough Court
                                            133 Fleet Street
                                            London EC4A 2BB


Ms Mary Skelley (Company Secretary)
Marconi Corp. Plc
34 Grosvenor Square
London
W1K 2HD

                                                                22 January 2004



Dear Sir/Madam,



UK Companies Act 1985 - Sections 198-203 - Marconi Corp Plc (the "Company")

This notification relates to issued ordinary shares in the capital of the
Company ("shares") and is given in fulfilment of the obligations imposed by
sections 198 to 203 of the Companies Act 1985 (the "Act").


It has come to our attention that at close of business on 21 January 2004, The
Goldman Sachs Group, Inc., of 85 Broad Street, New York, NY 10004, USA, was
interested in 12,042,729 shares.

Of these 12,042,729 shares,


a)     The interest in 3,361,262 shares arose from the interest held by Goldman, 
Sachs & Co. ("GS&Co"), acting as custodian.  These shares are, or will be, 
registered in the name of Goldman Sachs Securities (Nominees),
Limited ("GSSN").

b)     The interest in 8,662 shares arose from the interest held by GS&Co., 
acting as custodian of 4,331 American Depositary Receipts ("ADRs").  These ADRs 
are, or will be, held at the Depository Trust Company of New York ("DTC").

c)     The interest in 6,404,535 shares arose from a beneficial interest held by 
Goldman Sachs International.  These shares are, or will be, registered at CREST 
in account CREPTEMP.

d)     The interest in 2,268,270 shares arose from a beneficial interest of 
1,133,635 ADRs held by GSI.  These ADRs are, or will be, held at DTC.


A copy of this fax is being sent to you by post.  Please do not hesitate to
contact me should you have any questions.


Yours faithfully


For and on behalf of
The Goldman Sachs Group, Inc.




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