RNS Number:1378Q
Marconi Corporation PLC
24 September 2003


                                                                Press enquiries:
                   Joe Kelly tel: +44 207 306 1771; email: joe.kelly@marconi.com
                 David Beck tel: +44 207 306 1490; email: david.beck@marconi.com
                                                                                
                                                             Investor enquiries:
          Heather Green tel: + 44 207 306 1735; email: heather.green@marconi.com

                                                                                

                            MARCONI CORPORATION PLC                             
                 SALE OF SHAREHOLDING IN BOOKHAM TECHNOLOGY PLC                 

LONDON - 24 September 2003 - Marconi Corporation plc (London: MONI)
announces that it has today sold its holding of 12,891,000 shares in Bookham
Technology plc (LSE: BHM; Nasdaq: BKHM) through a placing with institutional
investors carried out by Cazenove & Co. Ltd for a total cash consideration of
#16,758,300.  The cash proceeds will be paid into a mandatory redemption escrow
account and will be used, in due course, to fund a further partial redemption of
the Group's Junior Notes.

Marconi acquired its holding in Bookham Technology in February 2002 as
consideration against the sale of its Optical Components business to Bookham.  

ENDS/...

About Marconi Corporation plc Redemption Escrow Account (MREA)

When the balance of the MREA reaches US$30 million, this triggers a mandatory
partial redemption of Marconi's Junior Notes at 110 per cent of par value.


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 under the symbol MONI.
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 forward-looking statements with respect to products,
partners, customers, future growth and other matters. Please refer to the Form
20-F report and Form 6-K reports filed by Marconi Corporation plc with the
United States Securities and Exchange Commission for a discussion of risks that
could cause actual results to differ materially from such statements.




                      This information is provided by RNS
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