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                                                                   EXHIBIT 4.111

                                                          CLIFFORD CHANCE US LLP

                                                                  CONFORMED COPY

                 MARCONI INTELLECTUAL PROPERTY (RINGFENCE) INC.,
                                   AS PLEDGOR

                                       AND

                   THE LAW DEBENTURE TRUST CORPORATION p.l.c.,
                                AS SECURED PARTY

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                               SECURITY AGREEMENT

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                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
SECTION                                                                                               PAGE
<S>                                                                                                   <C>
Section 1.   Definitions............................................................................    1

Section 2.   Grant of Security Interest.............................................................    4

Section 3.   Authorization; Responsibility..........................................................    5

Section 4.   Relation to Other Security Documents...................................................    5

Section 5.   Representations and Warranties.........................................................    6

Section 6.   Covenants..............................................................................    6

Section 7.   Limitations on Requirements as to Perfection...........................................   11

Section 8.   Inspection and Verification............................................................   12

Section 9.   Collateral Protection Expenses; Preservation of Collateral.............................   13

Section 10.  Securities and Deposits................................................................   13

Section 11.  Notification to Account Debtors and Other Persons Obligated on Collateral..............   13

Section 12.  Power of Attorney......................................................................   14

Section 13.  Remedies...............................................................................   15

Section 14.  Standards for Exercising Remedies......................................................   16

Section 15.  Waivers by Pledgor; Obligations Absolute...............................................   16

Section 16.  Marshalling............................................................................   17

Section 17.  Proceeds of Dispositions...............................................................   17

Section 18.  Amounts Due Hereunder..................................................................   17

Section 19.  Termination............................................................................   18

Section 20.  Reinstatement..........................................................................   18

Section 21.  Miscellaneous..........................................................................   18

Exhibit A UCC PERFECTION CERTIFICATE
Exhibit B FORM OF COPYRIGHT SECURITY AGREEMENT SUPPLEMENT
Exhibit C FORM OF PATENT SECURITY AGREEMENT SUPPLEMENT
Exhibit D FORM OF TRADEMARK SECURITY AGREEMENT SUPPLEMENT
</TABLE>

<PAGE>

         SECURITY AGREEMENT (this "AGREEMENT") dated as of May 19, 2003, between
MARCONI INTELLECTUAL PROPERTY (RINGFENCE) INC., a Delaware corporation
("PLEDGOR"), and THE LAW DEBENTURE TRUST CORPORATION p.l.c. ("LAW DEBENTURE"),
as Security Trustee (together with any co-trustee, co-agent or other entity
appointed pursuant to clause 16 of the STID (as defined below) ("SECURED PARTY")
under the Security Trust and Intercreditor Deed dated the date hereof and made
among Marconi Corporation plc as Issuer; Secured Party; the persons listed in
Schedule 1 thereto as Guarantors; Law Debenture Trust Company of New York as
Senior Note Trustee; JPMorgan Chase Bank as Junior Note Trustee; HSBC Bank plc
as New Bonding Facility Agent and Escrow Bank; The Bank of New York as
Depositary, Paying Agent and Registrar; the persons listed in Part A of Schedule
2 thereto as Intra-Group Creditors; the persons listed in Part B of Schedule 2
thereto as Intra-Group Borrowers; and the persons listed in Schedule 3 thereto
as New Bonding Facility Banks (as amended, modified or supplemented from time to
time, the "STID").

         WHEREAS, Pledgor has entered into (i) the Guarantee of Senior Notes,
(ii) the Guarantee of Junior Notes and (iii) the Composite Guarantee, each dated
the date hereof in favor of Secured Party (collectively, the "GUARANTEES"),
pursuant to which Pledgor has agreed to guarantee certain obligations and to
secure those obligations and, in connection therewith, inter alia, to execute
and deliver to Secured Party a security agreement in substantially the form
hereof;

         NOW, THEREFORE, in consideration of the premises and for other good and
valuable consideration the receipt and sufficiency of which are hereby
acknowledged, the parties hereto agree as follows:

         Section 1.        DEFINITIONS.

                  1.01.    Definition of Terms Used Herein Generally. Unless
otherwise defined herein, terms defined in the STID and used herein have the
meanings given to them in the STID. All terms used herein and defined in the
NYUCC shall have the same definitions herein as specified therein; provided,
however, that if a term is defined in Article 9 of the NYUCC differently than in
another Article of the NYUCC, the term has the meaning specified in Article 9 of
the NYUCC.

                  1.02.    Definition of Certain Terms Used Herein. As used
herein, the following terms shall have the following meanings:

         "COLLATERAL" shall have the meaning assigned to such term in Section 2.

         "COPYRIGHT LICENSE" shall mean any written agreement, now or hereafter
in effect, granting any right to any third party under any Copyright now or
hereafter owned by Pledgor or that Pledgor otherwise has the right to license,
or granting any right to Pledgor under any Copyright now or hereafter owned by
any third party or that any third party otherwise has the right to license, and
all rights of Pledgor under any such agreement.

         "COPYRIGHT OFFICE" shall mean the United States Copyright Office.

         "COPYRIGHT SECURITY AGREEMENT SUPPLEMENT" shall mean a supplement to
this Agreement, executed by Pledgor in favor of Secured Party, substantially in
the form of Exhibit B hereto.

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                                                                               2

         "COPYRIGHTS" shall mean (a) all copyright rights in any work subject to
the copyright laws of the United States or any other country, whether as author,
assignee, transferee or otherwise, and (b) all registrations and applications
for registration of any such copyright in the United States or any other country
and all extensions and renewals thereof.

         "DEFAULT" shall mean any event or circumstance that constitutes a
Default under the Senior Note Indenture or the Junior Note Indenture.

         "DEPOSITARY" shall have the meaning assigned to such term in the
Deposit Account Control Agreement.

         "DEPOSIT ACCOUNT CONTROL AGREEMENT" shall mean an agreement in form and
substance satisfactory to Secured Party, pursuant to which the relevant
depositary bank agrees, inter alia, to comply with instructions originated by
Secured Party directing disposition of the funds in the relevant deposit account
without further consent by Pledgor, and not to comply with any instructions
originated by Pledgor directing disposition of such funds, in each case upon
receipt by such depositary bank of a written notice from Secured Party to such
effect.

         "EVENT OF DEFAULT" shall mean any event or circumstance that
constitutes an Event of Default under the Senior Note Indenture or the Junior
Note Indenture.

         "GOVERNMENT DEBTOR" shall have the meaning assigned to such term in
Section 5.01(a).

         "INTELLECTUAL PROPERTY" shall mean all intellectual and similar
property of Pledgor of every kind and nature now owned or hereafter acquired by
Pledgor, including inventions, designs, Patents, Patent Licenses, Trademarks,
Trademark Licenses, Copyrights, Copyright Licenses, trade secrets, confidential
or proprietary technical and business information, know-how, show-how or other
data or information, software and databases and all embodiments or fixations
thereof and related documentation, registrations and franchises, licenses for
any of the foregoing and all license rights, and all additions, improvements and
accessions to, and books and records describing or used in connection with, any
of the foregoing.

         "LIEN" shall have the meaning assigned to the term "Security" in the
STID.

         "NYUCC" shall mean the Uniform Commercial Code as in effect in the
State of New York from time to time.

         "PATENT LICENSE" shall mean any written agreement, now or hereafter in
effect, granting to any third party any right to make, use or sell any invention
on which a Patent, now or hereafter owned by Pledgor or that Pledgor otherwise
has the right to license, is in existence, or granting to Pledgor any right to
make, use or sell any invention on which a Patent, now or hereafter owned by any
third party, is in existence or that any third party otherwise has the right to
license, and all rights of Pledgor under any such agreement.

         "PATENT SECURITY AGREEMENT SUPPLEMENT" shall mean a supplement to this
Agreement, executed by Pledgor in favor of Secured Party, substantially in the
form of Exhibit C hereto.

         "PATENTS" shall mean (a) all letters patent of the United States or any
other country, all registrations and recordings thereof, and all pending
applications for letters patent of the United States or any other country,
including registrations, recordings and applications in the PTO or in any
similar office

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                                                                               3

or agency of the United States, any State or Territory thereof, or any other
country, and (b) all reissues, continuations, divisions, continuations-in-part,
renewals or extensions thereof and the inventions disclosed or claimed therein,
including the right to make, use and/or sell inventions disclosed or claimed
therein.

         "PERFECTION CERTIFICATE" shall mean a certificate substantially in the
form of Exhibit A hereto, completed and supplemented with the schedules and
attachments contemplated thereby, and duly executed by Pledgor.

         "PERFECTION SUPPLEMENT" shall have the meaning assigned to such term in
Section 6.14.

         "PTO" shall mean the United States Patent and Trademark Office.

         "SECURED OBLIGATIONS" shall mean all present and future indebtedness,
liabilities and obligations (for the avoidance of doubt, including any
liabilities and obligations which have been cash-collateralized by the Pledgor)
at any time of the Pledgor under the Relevant Documents, both actual and
contingent and whether incurred solely or jointly or in any other capacity
together with any of the following matters relating to or arising in respect of
those liabilities and obligations:.

         (a)      any refinancing, novation, deferral or extension;

         (b)      any obligation relating to any increase in the amount of such
                  obligations;

         (c)      any claim for damages or restitution; and

         (d)      any claim as a result of any recovery by the Pledgor of a
                  payment or discharge, or non-allowability, on the grounds of
                  preference,

and any amounts that would be included in any of the above but for any
discharge, non-provability or unenforceability of those amounts in any
insolvency or other proceedings (including interest accruing after the
commencement of any insolvency or other proceedings).

         "SECURITY DOCUMENTS" shall mean this Agreement, the Perfection
Certificate, the Stock Pledge Agreement, the Deposit Account Control Agreements
and the other documents, agreements and supplements to be executed pursuant to
the terms hereof, each as entered into, or as shall be entered into, by Pledgor.

         "SECURITY INTEREST" shall mean the security interest granted pursuant
to Section 2, as well as all other security interests created or assigned as
additional security for the Secured Obligations pursuant to the provisions of
this Agreement.

         "STID" shall have the meaning assigned to such term in the preamble to
this Agreement.

         "STOCK PLEDGE AGREEMENT" shall mean the stock pledge agreement dated on
or about the date hereof between Secured Party and Pledgor.

         "TRADEMARK LICENSE" shall mean any written agreement, now or hereafter
in effect, granting to any third party any right to use any Trademark now or
hereafter owned by Pledgor or that Pledgor otherwise has the right to license,
or granting to Pledgor any right to use any Trademark now or hereafter owned by
any third party or that any third party otherwise has the right to license, and
all rights of Pledgor under any such agreement.

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                                                                               4

         "TRADEMARK SECURITY AGREEMENT SUPPLEMENT" shall mean a supplement to
this Agreement, executed by Pledgor in favor of Secured Party, substantially in
the form of Exhibit D hereto.

         "TRADEMARKS" shall mean (a) all trademarks, service marks, trade names,
corporate names, company names, business names, fictitious business names, trade
styles, trade dress, logos, other source or business identifiers, designs and
general intangibles of like nature, now existing or hereafter adopted or
acquired, all registrations and recordings thereof, and all registration and
recording applications filed in connection therewith, including registrations
and registration applications in the PTO, any State of the United States or any
similar offices in any other country or any political subdivision thereof, and
all extensions or renewals thereof, (b) all goodwill associated therewith or
symbolized thereby and (c) all other assets, rights and interests that uniquely
reflect or embody such goodwill.

         "UCC" shall mean the Uniform Commercial Code as in effect in any
jurisdiction (except as otherwise contemplated in Section 6.15). References to
particular sections of Article 9 of the UCC shall be, unless otherwise
indicated, references to Revised Article 9 of the UCC adopted and effective in
certain jurisdictions on or after July 1, 2001.

                  1.03.    Rules of Interpretation.

The rules of interpretation specified in clause 1.2 of the STID shall be
applicable to this Agreement.

"continuing" in relation to an Enforcement Event shall be construed as a
reference to an acceleration of any Secured Obligation (other than Secured
Obligations arising under the New Bonding Facility Agreement) where such
acceleration has not been rescinded in writing or a declaration that the Secured
Obligations (other than Secured Obligations arising under the New Bonding
Facility Agreement) are prematurely due and payable (other than solely as a
result of it becoming unlawful for a Secured Creditor to perform its obligations
under the Relevant Documents) where such declaration has not been revoked in
writing or any failure by an Obligor to pay any principal amount in respect of
any Secured Obligations (other than Secured Obligations arising under the New
Bonding Facility Agreement) whether on maturity or otherwise which has not been
waived in writing. For purposes of this clause, "Secured Obligations" shall have
the meaning assigned to such term in the STID.

                  1.04.    STID. The parties hereto acknowledge that Secured
Party, when acting hereunder, shall be acting in accordance with and subject to
the terms of the STID.

                  1.05.    Conflict. Notwithstanding any provision to the
contrary contained herein, the parties agree that this Agreement is subject in
all respects to the STID and for the avoidance of doubt, in the event of any
inconsistency, the provisions of the STID shall prevail.

         Section 2.        GRANT OF SECURITY INTEREST. To secure the payment or
performance, as the case may be, in full of the Secured Obligations, Pledgor
hereby grants to Secured Party a security interest in and mortgage on and
pledges and assigns to Secured Party, its successors and assigns the following
properties, assets and rights of Pledgor, wherever located, whether now owned or
hereafter acquired or arising, and all proceeds and products thereof (all of the
same being hereinafter called the "COLLATERAL"): all personal property and
fixtures of every kind and nature, including without limitation all goods
(including without limitation inventory, equipment and any accessions thereto),
instruments (including

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                                                                               5

without limitation promissory notes), documents, accounts (including without
limitation health-care-insurance receivables), chattel paper (whether tangible
or electronic), deposit accounts, letter-of-credit rights (whether or not the
letter of credit is evidenced by a writing), money, tort claims, securities and
all other investment property, supporting obligations, any other contract rights
or rights to the payment of money, insurance claims and proceeds, and all
general intangibles (including without limitation all Intellectual Property,
insurance policies and payment intangibles). Secured Party acknowledges that the
attachment of its security interest in any commercial tort claim as original
collateral is subject to Pledgor's compliance with Section 6.10.

         Section 3.        AUTHORIZATION; RESPONSIBILITY .

                  3.01.    Authorization to File Financing Statements. Pledgor
hereby irrevocably authorizes Secured Party at any time and from time to time to
file in any jurisdiction in which the UCC has been adopted any initial financing
statements and amendments thereto that (a) indicate the Collateral (i) as all
assets of Pledgor or words of similar effect, regardless of whether any
particular asset comprised in the Collateral falls within the scope of Article 9
of the NYUCC or such jurisdiction, or (ii) as being of an equal or lesser scope
or with greater detail, and (b) contain any other information required by part 5
of Article 9 of the UCC for the sufficiency or filing office acceptance of any
initial financing statement or amendment, including (i) the type of organization
of Pledgor and any organization identification number issued to Pledgor and,
(ii) in the case of a financing statement filed as a fixture filing or
indicating Collateral as timber to be cut or as-extracted collateral, a
sufficient description of real property to which such Collateral relates.
Pledgor agrees to furnish any such information to Secured Party promptly upon
request. Pledgor also ratifies its authorization for Secured Party to have filed
in any UCC jurisdiction any like initial financing statements or amendments
thereto if filed prior to the date hereof. The authorization conferred on
Secured Party under this Section 3 is solely to protect Secured Party's interest
in the Pledged Collateral and shall not impose any duty on Secured Party to act.

                  3.02.    No Responsibility to Perfect. Clause 14.8 of the STID
is hereby incorporated herein by this reference with the same effect as though
set forth in its entirety herein.

         Section 4.        RELATION TO OTHER SECURITY DOCUMENTS. The provisions
of this Agreement supplement the provisions of any real estate mortgage or deed
of trust granted by Pledgor to Secured Party and securing the payment or
performance of any of the Secured Obligations. Nothing contained in any such
real estate mortgage or deed of trust shall derogate from any of the rights or
remedies of Secured Party hereunder.

                  4.01.    Other Security Documents. Concurrently herewith
Pledgor is executing and delivering to Secured Party the other Security
Documents. All collateral covered by such other Security Documents shall be
governed by the terms of such other Security Documents and not by the terms of
this Agreement (to the extent that the terms of such other Security Documents
conflict with the terms hereof).

                  4.02.    Patent and Trademark Security Agreement Supplements.
Concurrently herewith Pledgor is executing and delivering to Secured Party for
recording in the PTO the Patent Security Agreement Supplement and the Trademark
Security Agreement Supplement. The provisions of the Patent Security Agreement
Supplement and the Trademark Security Agreement Supplement are supplemental to
the provisions of this Agreement. Nothing contained in the Patent Security
Agreement

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                                                                               6

Supplement or the Trademark Security Agreement Supplement shall derogate from
any of the rights or remedies of Secured Party hereunder, nor shall anything
contained in the Patent Security Agreement Supplement or the Trademark Security
Agreement Supplement be deemed to prevent or extend the time of attachment or
perfection of any Security Interest in such Collateral created hereby.

                  4.03.    Omitted.

         Section 5.        REPRESENTATIONS AND WARRANTIES. Pledgor represents
and warrants to Secured Party as follows:

                  5.01.    Nature of Collateral. None of the Collateral
constitutes, or is the proceeds of, farm products and none of the Collateral has
been purchased will be used by Pledgor primarily for personal, family or
household purposes, and except as indicated in the Perfection Certificate:

                           (a)      none of the account debtors or other persons
obligated on any of the Collateral is a governmental authority subject to the
Federal Assignment of Claims Act or like federal, state or local statute or rule
in respect of such Collateral (a "GOVERNMENT Debtor"), which Collateral has a
value of at least $1,000,000, and, in the case of Collateral that is a contract,
also has a term of at least one (1) year.

                           (b)      Pledgor holds no commercial tort claims.

                  5.02.    Perfection Certificate; Perfection.

                           (a)      All information set forth on the Perfection
Certificate is, and all information set forth on each Perfection Supplement
shall be, accurate and complete.

                           (b)      A fully executed Patent Security Agreement
Supplement, Trademark Security Agreement Supplement and a Copyright Security
Agreement Supplement containing a description of all Collateral consisting of
United States Patents and United States registered Trademarks (and Trademarks
for which United States registration applications are pending) and United States
registered Copyrights owned by Pledgor on the date hereof have been delivered to
Secured Party for recording by the PTO and the Copyright Office, as necessary,
pursuant to 35 U.S.C. Section 261, 15 U.S.C. Section 1060 or 17 U.S.C. Section
205 and the regulations thereunder, as applicable.

         Section 6.        COVENANTS. Pledgor covenants and agrees with Secured
Party, in each case at Pledgor's own cost and expense, as follows.

                  6.01.    Pledgor's Name, Legal Status, Locations. Without
providing at least thirty (30) days' prior written notice to Secured Party,
Pledgor shall not change (a) its name; (b) its type of organization, its
jurisdiction or organization or other legal structure; or (c) its place of
business or (if it has more than one place of business) its chief executive
office or its mailing address.

                  6.02.    Pledgor's Organizational Number. Without providing at
least thirty (30) days' prior written notice to Secured Party, Pledgor shall not
change its organizational identification number if it has one. If Pledgor does
not have an organizational identification number and later obtains one, Pledgor
shall forthwith notify Secured Party of such organizational identification
number.

                  6.03.    Title to Collateral. (a) Except for the Security
Interest herein granted and Liens not expressly prohibited by the Indentures,
Pledgor shall be the owner of the Collateral free from (and

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                                                                               7

Pledgor shall not create or suffer to exist on the Collateral) any Lien; and (b)
Pledgor shall not pledge, mortgage or create, or suffer to exist a Lien on the
Collateral in favor of any person other than Secured Party except for Liens
permitted by the Indentures.

                  6.04.    Promissory Notes and Tangible Chattel Paper. Subject
to Section 7, if Pledgor shall at any time hold or acquire any promissory notes
or tangible chattel paper, Pledgor shall forthwith endorse, assign and deliver
the same to Secured Party, accompanied by such instruments of transfer or
assignment duly executed in blank as Secured Party may from time to time specify
and with respect to any such Collateral in the possession or control of Secured
Party, Pledgor waives any restriction or obligation imposed on Secured Party by
Sections 9-207(c)(1) and 9-207(c)(2) of the NYUCC. Secured Party agrees that,
upon written request from Pledgor certifying that Pledgor requires possession of
a promissory note or tangible chattel paper then in the possession of Secured
Party in order to enforce the same, it shall deliver to Pledgor such promissory
note or tangible chattel paper to Pledgor; Pledgor agrees that such promissory
note or tangible chattel paper shall be held to the order of Secured Party.

                  6.05.    Deposit Accounts. Subject to Section 7, for each
deposit account that Pledgor at any time opens or maintains, Pledgor shall cause
the depositary bank to enter into a Deposit Account Control Agreement. Secured
Party agrees with Pledgor that Secured Party shall not give to any Depositary
the notice referred to in Section 2.01 of the Deposit Account Control Agreement
or withhold any withdrawal rights from Pledgor, unless an Enforcement Event has
occurred and is continuing. The foregoing provisions of this Section 6.05 shall
not apply to (i) deposit accounts for which Secured Party is the depositary bank
and (ii) deposit accounts specially and exclusively used for payroll, payroll
taxes and other employee wage and benefit payments to or for the benefit of
Pledgor's salaried employees. With respect to any deposit accounts, rights
arising under deposit accounts or proceeds thereof in the possession or within
the control of Secured Party, Pledgor waives any restriction or obligation
imposed on Secured Party by Sections 9-207(c)(1), 9-207(c)(2) and 9-208 of the
NYUCC.

                  6.06.    Investment Property. If Pledgor shall at any time
hold or acquire any certificated securities, Pledgor shall forthwith endorse,
assign and deliver the same to Secured Party, accompanied by such instruments of
transfer or assignment duly executed in blank as Secured Party may from time to
time specify. If any securities now owned or hereafter acquired by Pledgor are
uncertificated and are issued to Pledgor or its nominee directly by the issuer
thereof, Pledgor shall immediately notify Secured Party thereof and shall cause
the issuer to enter into a written agreement or other authenticated record with
Secured Party, in form and substance satisfactory to Secured Party, pursuant to
which such issuer shall agree, among other things, to comply with instructions
from Secured Party as to such securities, without further consent of Pledgor or
such nominee; in the event Pledgor is unable or otherwise fails to obtain such
written agreement or other authenticated record from an issuer, Pledgor shall
arrange for Secured Party or a Delegate to become the registered owner of the
securities. If any securities, whether certificated or uncertificated, or other
investment property now or hereafter acquired by Pledgor are held or acquired by
Pledgor or its nominee through a securities intermediary or commodity
intermediary, Pledgor shall immediately notify Secured Party thereof and shall
cause such securities intermediary or (as the case may be) commodity
intermediary to enter into a written agreement or other authenticated record
with Secured Party, in form and substance satisfactory to Secured Party,
pursuant to which such securities intermediary or commodities intermediary, as
the case may be, shall, among other things, agree to comply

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                                                                               8

with entitlement orders or other instructions from Secured Party to such
securities intermediary as to such securities or other investment property, or
(as the case may be) to apply any value distributed on account of any commodity
contract as directed by Secured Party to such commodity intermediary, in each
case without further consent of Pledgor or such nominee; in the event Pledgor is
unable or otherwise fails to obtain such written agreement or other
authenticated record from a securities intermediary or commodities intermediary,
as the case may be, Pledgor shall, in the case of financial assets or other
investment property held through a securities intermediary, arrange for Secured
Party or a Delegate to become the entitlement holder with respect to such
investment property, with Pledgor being permitted, only with the consent of
Secured Party (acting on instructions received pursuant to the terms of the
STID), to exercise rights to withdraw or otherwise deal with such investment
property. Secured Party agrees with Pledgor that Secured Party shall not give
any such entitlement orders or instructions or directions to any such issuer,
securities intermediary or commodity intermediary, and shall not withhold its
consent to the exercise of any withdrawal or dealing rights by Pledgor, unless
an Enforcement Event has occurred and is continuing or, after giving effect to
any such investment and withdrawal rights not otherwise permitted by the
Relevant Documents, a Default or Event of Default would occur. The provisions of
this Section 6.06 shall not apply to any financial assets credited to a
securities account for which Secured Party is the securities intermediary. With
respect to any such Collateral in the possession or within the control of
Secured Party, Pledgor waives any restriction or obligation imposed on Secured
Party by Sections 9-207(c)(1), 9-207(c)(2) and 9-208 of the NYUCC.

                  6.07.    Collateral in the Possession of a Bailee. Subject to
Section 7, if any goods are at any time in the possession of a bailee (which
bailee has agreed to hold or in fact holds such goods for more than ninety (90)
days), Pledgor shall promptly notify Secured Party thereof and shall use
commercially reasonable efforts promptly to obtain an acknowledgement from such
bailee, in form and substance satisfactory to Secured Party, that such bailee
holds such Collateral for the benefit of Secured Party and shall act upon the
instructions of Secured Party, without the further consent of Pledgor. Secured
Party agrees with Pledgor that Secured Party shall not give any such
instructions unless an Enforcement Event has occurred and is continuing or a
Default or Event of Default would occur after taking into account any action by
Pledgor with respect to such bailee. With respect to any such Collateral in the
possession or within the control of Secured Party or a bailee, Pledgor waives
any restriction or obligation imposed on Secured Party by Sections 9-207(c)(1)
and 9-207(c)(2) of the UCC.

                  6.08.    Electronic Chattel Paper and Transferable Records.
Subject to Section 7, if Pledgor at any time holds or acquires an interest in
any electronic chattel paper or any "transferable record," as that term is
defined in Section 201 of the federal Electronic Signatures in Global and
National Commerce Act, or in Section 16 of the Uniform Electronic Transactions
Act as in effect in any relevant jurisdiction, Pledgor shall promptly notify
Secured Party thereof and shall use commercially reasonable efforts to vest in
Secured Party control, under Section 9-105 of the UCC, of such electronic
chattel paper or control under Section 201 of the federal Electronic Signatures
in Global and National Commerce Act or, as the case may be, Section 16 of the
Uniform Electronic Transactions Act, as so in effect in such jurisdiction, of
such transferable record. Secured Party agrees with Pledgor that Secured Party
shall arrange, pursuant to procedures satisfactory to Secured Party and so long
as such procedures will not result in Secured Party's loss of control, for
Pledgor to make alterations to the electronic chattel paper or transferable
record permitted under Section 9-105 of the UCC or, as the case may be, Section
201 of the

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                                                                               9

federal Electronic Signatures in Global and National Commerce Act or Section 16
of the Uniform Electronic Transactions Act, unless an Enforcement Event has
occurred and is continuing or a Default or Event of Default would occur after
taking into account any action by Pledgor with respect to such electronic
chattel paper or transferable record. With respect to any such Collateral in the
possession or within the control of Secured Party, Pledgor waives any
restriction or obligation imposed on Secured Party by Sections 9-207(c)(1),
9-207(c)(2) and 9-208 of the NYUCC.

                  6.09.    Letter of Credit Rights. Subject to Section 7, if
Pledgor is at any time a beneficiary under a letter of credit now or hereafter
issued in favor of Pledgor with a term of ninety (90) days or longer, Pledgor
shall promptly notify Secured Party thereof and Pledgor shall use commercially
reasonable efforts to arrange, for the issuer and any nominated person with
respect to such letter of credit to consent, pursuant to an agreement or other
authenticated record with and in form and substance satisfactory to Secured
Party, to an assignment to Secured Party of the proceeds of any drawing under
the letter of credit ; in the event Pledgor is unable or otherwise fails to
obtain such agreement or other authenticated record from an issuer, Pledgor
shall arrange for Secured Party or a Delegate to become the transferee
beneficiary of the letter of credit, with Secured Party agreeing, in each case,
that the proceeds of any drawing under the letter of credit are to be applied as
provided in the STID. With respect to any such Collateral in the possession or
within the control of Secured Party, Pledgor waives any restriction or
obligation imposed on Secured Party by Sections 9-207(c)(1), 9-207(c)(2) and
9-208 of the NYUCC.

                  6.10.    Commercial Tort Claims. Subject to Section 7, if
Pledgor shall at any time hold or acquire a commercial tort claim, Pledgor shall
upon the assertion of such claim in litigation, arbitration or any other
proceeding (whether by way of the filing of a complaint, counterclaim, cross
claim or otherwise), notify Secured Party in a writing signed by Pledgor of the
brief details thereof and grant to Secured Party in such writing a security
interest therein and in the proceeds thereof, all upon the terms of this
Agreement, with such writing to be in form and substance satisfactory to Secured
Party.

                  6.11.    Intellectual Property.

                           (a)      Pledgor shall within twenty (20) days of (i)
filing an application for the registration of any Patent, Trademark, or
Copyright with the PTO, the Copyright Office or any similar office or agency of
any jurisdiction, and (ii) receiving a notice of any Patent, Trademark or
Copyright registration from the PTO, the Copyright Office or any similar office
or agency of any jurisdiction (whether by itself or through any agent, employee,
licensee or designee) give Secured Party written notice thereof, and shall
execute and deliver to Secured Party any and all Patent Security Agreement
Supplements, Trademark Security Agreement Supplements or Copyright Security
Agreement Supplements as Secured Party may request to evidence Secured Party's
Security Interest in such Patent, Trademark or Copyright, and the general
intangibles of Pledgor relating thereto or represented thereby.

                           (b)      Pledgor shall take all actions requested by
Secured Party to maintain and pursue each application, to obtain the relevant
registration and to maintain the registration of its Patents or Trademarks (now
or hereafter existing), including the filing of applications for renewal,
affidavits of use, affidavits of noncontestability and opposition and
interference and cancellation proceedings, unless Pledgor shall reasonably
determine that such Patent or Trademark is not material to the conduct of its
business.

<PAGE>

                                                                              10

                           (c)      With respect to any Intellectual Property
constituting Collateral that Pledgor has reasonably determined continues to be
useful and material to the conduct of Pledgor's business, Pledgor shall manage
such Intellectual Property consistent with its past practices related to
prosecution, maintenance, dedication to the public, abandonment, protection and
enforcement of Intellectual Property.

                           (d)      Pledgor assumes all responsibility and
liability arising from the use of the Intellectual Property and hereby
indemnifies and holds Secured Party and each other Secured Creditor harmless
from and against any claim, suit, loss, damage or expense (including attorneys'
fees arising out of any alleged defect in any product manufactured, promoted or
sold by Pledgor (or any affiliate or subsidiary thereof) in connection with such
Intellectual Property or out of the manufacture, promotion, labelling, sale or
advertisement of any such product by Pledgor (or any affiliate or subsidiary
thereof).

                  6.12.    Landlord Consents. Pledgor shall use commercially
reasonable efforts to deliver to Secured Party an executed letter in form and
substance acceptable to Secured Party from each landlord from which Pledgor
leases premises on which Goods or Inventory of Pledgor with a book value in
excess of ten million dollars ($10,000,000) is located, stored, used or held in
the United States of America promptly upon the book value of Goods or Inventory
located, stored, used or held at such premises reaching ten million dollars
($10,000,000) (each such letter, a "LANDLORD WAIVER LETTER") pursuant to which
such landlord, among other things, acknowledges the security interest granted by
Pledgor to Secured Party in such Goods and Inventory, waives or subordinates any
Lien such landlord may have in respect of such Goods or Inventory and agrees to
provide the Secured Party with access to such premises upon the occurrence and
during the continuance of an Event of Default.

                  6.13.    Dispositions of Collateral. Pledgor shall not sell or
otherwise dispose, or offer to sell or otherwise dispose, of the Collateral or
any interest therein except for (i) sales and leases of inventory in the
ordinary course of business and (ii) dispositions not expressly prohibited by
the Indentures.

                  6.14.    Periodic Certification. Each year, at the time of
delivery of annual financial statements with respect to the preceding fiscal
year pursuant to Section 4.20 of the Indentures, Pledgor shall deliver to
Secured Party a supplemental perfection certificate (each, a "PERFECTION
SUPPLEMENT") executed by Pledgor setting forth the information required pursuant
to the Perfection Certificate or confirming that there has been no change in
such information since the date of such certificate or the date of the most
recent certificate delivered pursuant to this Section 6.14.

                  6.15.    Other Actions as to any and all Collateral. Pledgor
further agrees to take any other action requested by Secured Party to ensure the
attachment and perfection of, and the ability of Secured Party to enforce, the
Security Interest created or purported to be created, in any and all of the
Collateral or for the exercise of rights and remedies of Secured Party provided
by or pursuant to this Agreement or by law including, without limitation, (a)
executing, delivering and, where appropriate, filing financing statements and
amendments relating thereto under the UCC; (b) causing Secured Party's name to
be noted as secured party on any certificate of title for a titled good if such
notation is a condition to attachment or perfection of, or ability of Secured
Party to enforce, the Security Interest in such Collateral; (c) complying with
any provision of any statute, regulation or treaty of the United States as to

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                                                                              11

any Collateral if compliance with such provision is a condition to the
attachment or perfection of, or the ability of Secured Party to enforce, the
Security Interest in such Collateral; (d) obtaining governmental and other third
party consents and approvals, including without limitation any consent of any
licensor, lessor or other person obligated on Collateral; (e) obtaining waivers
from mortgagees, bailees, landlords and any other person who has possession of
or any interest in any Collateral or any real property on which any Collateral
may be located, in form and substance satisfactory to Secured Party; and (f)
executing, delivering and recording, where applicable, such other documents or
instruments and taking all actions required by the UCC or by other law, as
applicable in any relevant UCC jurisdiction, or by other law as applicable in
any foreign jurisdiction.

                  6.16.    Federal Assignment of Claims Act. Subject to Section
7, Pledgor shall (x) within ten (10) Business Days of the existence of a
Governmental Debtor send to such entity a written request that such entity, in
writing (an "ACA LETTER") (i) consent to the security interest granted by
Pledgor to Secured Party in such Collateral, (ii) agree to do such other things
as may be necessary pursuant to the terms of the Collateral, and (iii) to agree
that, upon receipt of notice from Secured Party, such entity will make payments
under such Collateral as Secured Party shall direct; and (y) use commercially
reasonable efforts to deliver to Secured Party, within thirty (30) days of
Pledgor's request sent pursuant to clause (x) above, such ACA Letter executed by
such Governmental Debtor.

         Section 7.        LIMITATIONS ON REQUIREMENTS AS TO PERFECTION. The
covenants of Pledgor set forth in Sections 6.04, 6.05, 6.07, 6.08, 6.09, 6.10
and 6.16 are subject to the following limitations:

                           (a)      Pledgor shall not be required to comply with
the perfection requirements of Section 6.04 except with respect to any
promissory note or item of tangible commercial paper that evidences an
obligation of at least (i) $1,000,000, if there has occurred and is continuing a
Default or an Event of Default, of which occurrence the Issuer has notified the
Senior Note Trustee pursuant to Section 6.19 of the Senior Note Indenture or the
Junior Note Trustee pursuant to Section 6.19 of the Junior Note Indenture or of
which occurrence the Senior Note Trustee, the Holders of the Senior Note, the
Junior Note Trustee or the Holders of the Junior Notes have notified the Issuer
or (ii) $5,000,000, otherwise.

                           (b)      Pledgor shall not be required to comply with
the perfection requirements of Section 6.05 with respect to any bank account
that does not at any time have a credit balance of $150,000. Pledgor shall
within fifteen (15) Business Days after the date of this Agreement deliver to
Secured Party Deposit Account Control Agreements executed by depositary banks
with respect to bank accounts, the aggregate balance of which is at least 50% of
the aggregate balance of all bank accounts that are subject to the perfection
requirements of Section 6.05. Pledgor shall within thirty (30) days after the
date of this Agreement deliver to Secured Party Deposit Account Control
Agreements executed by depositary banks with respect to the remainder of the
bank accounts that are subject to the perfection requirements of Section 6.05.

                           (c)      Pledgor shall not be required to comply with
the perfection requirements of Section 6.07 except with respect to goods agreed
to be held or in fact held by a bailee, which goods have an aggregate book value
at least (i) $1,000,000, if there has occurred and is continuing a Default or an
Event of Default, of which occurrence the Issuer has notified the Senior Note
Trustee pursuant to Section 6.19 of the Senior Note Indenture or the Junior Note
Trustee pursuant to Section 6.19 of the

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                                                                              12

Junior Note Indenture, or of which occurrence the Senior Note Trustee, the
Holders of the Senior Notes, the Junior Note Trustee or the Holders of the
Junior Notes have notified the Issuer or (ii) $5,000,000, otherwise.

                           (d)      Pledgor shall not be required to comply with
the perfection requirements of Section 6.08 except with respect to any item of
electronic chattel paper or any transferable record that evidences an obligation
of at least (i) $1,000,000, if there has occurred and is continuing a Default or
an Event of Default, of which occurrence the Issuer has notified the Senior Note
Trustee pursuant to Section 6.19 of the Senior Note Indenture or the Junior Note
Trustee pursuant to Section 6.19 of the Junior Note Indenture, or of which
occurrence the Senior Note Trustee, the Holders of the Senior Notes, the Junior
Note Trustee or the Holders of the Junior Notes have notified the Issuer or (ii)
$5,000,000, otherwise.

                           (e)      Pledgor shall not be required to comply with
the perfection requirements of Section 6.09 except with respect to one or more
letters of credit issued by an issuer for the benefit of Pledgor, which letters
of credit have an aggregate face amount of at least (i) $1,000,000, if there has
occurred and is continuing a Default or an Event of Default, of which occurrence
the Issuer has notified the Senior Note Trustee pursuant to Section 6.19 of the
Senior Note Indenture or the Junior Note Trustee pursuant to Section 6.19 of the
Junior Note Indenture, or of which occurrence the Senior Note Trustee, the
Holders of the Senior Notes, the Junior Note Trustee or the Holders of the
Junior Notes have notified the Issuer or (ii) $5,000,000, otherwise.

                           (f)      Pledgor shall not be required to comply with
the perfection requirements of Section 6.10 except with respect to Pledgor's
commercial tort claim or series of related commercial tort claims worth at least
(i) $1,000,000, if there has occurred and is continuing a Default or an Event of
Default, of which occurrence the Issuer has notified the Senior Note Trustee
pursuant to Section 6.19 of the Senior Note Indenture or the Junior Note Trustee
pursuant to Section 6.19 of the Junior Note Indenture, or of which occurrence
the Senior Note Trustee, the Holders of the Senior Notes, the Junior Note
Trustee or the Holders of the Junior Notes have notified the Issuer or (ii)
$5,000,000, otherwise.

                           (g)      Pledgor shall not be required to comply with
the perfection requirements of Section 6.16 except (i) with respect to any item
of Collateral that has a value of at least $1,000,000, and, in the case of
Collateral that is a contract, also has a term of at least one (1) year; and
(ii) if there has occurred and is continuing (a) an Insolvency Event of Default,
(b) an Enforcement Event or (c) the occurrence of any Event of Default with
respect to which the Security Trustee has been instructed under the STID; and
(iii) upon the request of the Secured Party, acting upon instructions pursuant
to the STID.

         Section 8.        INSPECTION AND VERIFICATION. Secured Party and such
Persons as Secured Party may designate shall have the right, as reasonably
required and upon reasonable notice, at Pledgor's own cost and expense, to
inspect the Collateral, all records related thereto (and to make extracts and
copies from such records) and the premises upon which any of the Collateral is
located, to discuss Pledgor's affairs with the officers of Pledgor and its
independent accountants and to verify the validity, amount, quality, quantity,
value, condition and status of, or any other matter relating to, the Collateral,
including by contacting account debtors or others obligated with respect to
Collateral and, in the case of Collateral in the possession of any third person,
the third Person possessing such Collateral.

<PAGE>

                                                                              13

         Section 9.        COLLATERAL PROTECTION EXPENSES; PRESERVATION OF
COLLATERAL.

                  9.01.    Expenses Incurred by Secured Party. If Pledgor fails
to discharge taxes or other encumbrances at any time levied or placed on any of
the Collateral, make repairs thereto or pay any necessary filing fees or
insurance premiums, Secured Party may, in its discretion, discharge such taxes
and other encumbrances, make such repairs and pay such filing fees or insurance
premiums. Secured Party shall have no obligation to Pledgor to make any such
expenditures, nor shall the making thereof relieve Pledgor of any default.
Pledgor shall reimburse Secured Party immediately upon demand for any such
expenditures pursuant to Section 21.09.

                  9.02.    Secured Party's Obligations and Duties. Anything
herein to the contrary notwithstanding, Pledgor shall remain liable under each
contract or agreement comprised in the Collateral to be observed or performed by
Pledgor thereunder. Secured Party shall not have any obligation or liability
under any such contract or agreement by reason of or arising out of this
Agreement or the receipt by Secured Party of any payment relating to any of the
Collateral, nor shall Secured Party be obligated in any manner to perform any of
the obligations of Pledgor under or pursuant to any such contract or agreement,
to make inquiry as to the nature or sufficiency of any payment received by
Secured Party in respect of the Collateral or as to the sufficiency of any
performance by any party under any such contract or agreement, to present or
file any claim, to take any action to enforce any performance or to collect the
payment of any amounts that may have been assigned to Secured Party or to which
Secured Party may be entitled at any time or times. Secured Party's sole duty
with respect to the custody, safe keeping and physical preservation of the
Collateral in its possession, under Section 9-207 of the NYUCC or otherwise,
shall be to deal with such Collateral in the same manner as Secured Party deals
with similar property for its own account.

                  9.03.    Use of Collateral. With respect to any Collateral in
the possession of Secured Party, or a bailee or other third party holding on its
behalf, Secured Party (acting on instructions received pursuant to the terms of
the STID) may, at any time after the occurrence and during the continuance of an
Enforcement Event a, use or operate such Collateral in any manner and to the
extent determined by Secured Party.

         Section 10.       SECURITIES AND DEPOSITS. Without limitation of
Section 6.06, Secured Party (acting on instructions received pursuant to the
terms of the STID) may at any time after the occurrence and during the
continuance of an Enforcement Event, at its option, transfer to itself or any
nominee any securities constituting Collateral, receive any income thereon and
hold such income as additional Collateral or apply it to the Secured Obligations
in accordance with the STID. Whether or not any Secured Obligations are due,
Secured Party may after the occurrence and during the continuance of an
Enforcement Event demand, sue for, collect, or make any settlement or compromise
that it deems desirable with respect to the Collateral. Regardless of the
adequacy of Collateral or any other security for the Secured Obligations, any
deposits or other sums at any time credited by or due from Secured Party to
Pledgor may at any time be applied to or set off against any of the Secured
Obligations whether or not due and owing.

         Section 11.       NOTIFICATION TO ACCOUNT DEBTORS AND OTHER PERSONS
OBLIGATED ON COLLATERAL. If an Enforcement Event shall have occurred and be
continuing, Pledgor shall notify

<PAGE>

                                                                              14

account debtors and other persons obligated on any of the Collateral of the
security interest of Secured Party in any account, chattel paper, general
intangible, instrument or other Collateral and that payment thereof is to be
made directly to Secured Party or to any financial institution designated by
Secured Party as Secured Party's agent therefor, and Secured Party (acting on
instructions received pursuant to the terms of the STID) may itself, if an
Enforcement Event shall have occurred and be continuing, without notice to or
demand upon Pledgor, so notify account debtors and other persons obligated on
Collateral. After the giving of any such notification, Pledgor shall hold any
proceeds of collection of accounts, chattel paper, general intangibles,
instruments and other Collateral received by Pledgor as trustee for Secured
Party without commingling the same with other funds of Pledgor and shall turn
the same over to Secured Party in the identical form received, together with any
necessary endorsements or assignments. Secured Party may apply the proceeds of
collection of accounts, chattel paper, general intangibles, instruments and
other Collateral received by Secured Party to the Secured Obligations or hold
such proceeds as additional Collateral, at the option of Secured Party in
accordance with the STID. The provisions of Section 9-209 of the NYUCC shall not
apply to any account, chattel paper or payment intangible as to which
notification of assignment has been sent to the account debtor or other person
obligation on the Collateral.

         Section 12.       POWER OF ATTORNEY.

                  12.01.   Appointment and Powers of Secured Party. Pledgor
hereby irrevocably constitutes and appoints Secured Party and any director,
officer or agent thereof, with full power of substitution, as its true and
lawful attorneys-in-fact with full irrevocable power and authority in the place
and stead of Pledgor or in Secured Party's own name, for the purpose of carrying
out the terms of this Agreement, to take any and all appropriate action and to
execute any and all documents and instruments that may be necessary or desirable
to accomplish the purposes of this Agreement and any agreement entered into
pursuant to the terms hereof (including, without limitation, the Deposit Account
Control Agreements) and, without limiting the generality of the foregoing,
hereby gives said attorneys the power and right, on behalf of Pledgor, without
notice to or assent by Pledgor, to do the following:

                           (a)      upon the occurrence and during the
continuance of an Enforcement Event (and in accordance with clauses 9 and 10 of
the STID), and at the expense of Pledgor, generally to sell, transfer, pledge,
license, lease, otherwise dispose of, make any agreement with respect to or
otherwise deal with any of the Collateral in such manner as is consistent with
the NYUCC and as fully and completely as though Secured Party were the absolute
owner thereof for all purposes, and to do at Pledgor's expense, at any time, or
from time to time, all acts and things that Secured Party deems necessary to
protect, preserve or realize upon the Collateral and the Security Interest
therein, in order to effect the intent of this Agreement, all as fully and
effectively as Pledgor might do, including, without limitation: (i) making,
settling and adjusting claims in respect of Collateral under policies of
insurance, endorsing the name of such Pledgor on any check, draft, instrument or
other item of payment for the proceeds of such policies of insurance and for
making all determinations and decisions with respect thereto; (ii) filing and
prosecuting registration and transfer applications with the appropriate federal
or local agencies or authorities with respect to trademarks, copyrights and
patentable inventions and processes; (iii) upon written notice to Pledgor,
exercising voting rights with respect to voting securities, which rights may be
exercised, if Secured Party so elects, with a view to causing the liquidation in
a commercially reasonable manner of assets of the issuer of any such securities;
and (iv) executing,

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                                                                              15

delivering and recording, in connection with any sale or other disposition of
any Collateral, of the endorsements, assignments or other instruments of
conveyance or transfer with respect to such Collateral; and

                           (b)      to the extent that Pledgor's authorization
given in Section 3 is not sufficient to file such financing statements with
respect hereto, with or without Pledgor's signature, or a photocopy of this
Agreement in substitution for a financing statement, as Secured Party may deem
appropriate and to execute in Pledgor's name such financing statements and
amendments thereto and continuation statements that may require Pledgor's
signature.

                  12.02.   Ratification by Pledgor. To the extent permitted by
law, Pledgor hereby ratifies all that said attorneys shall lawfully do or cause
to be done by virtue of this Section 12. This power of attorney is a power
coupled with an interest and is irrevocable.

                  12.03.   No Duty on Secured Party. The powers conferred on
Secured Party, its directors, officers and agents pursuant to this Section 12
are solely to protect Secured Party's interests in the Collateral and shall not
impose any duty upon any of them to exercise any such powers. Secured Party
shall be accountable only for the amounts that it actually receives as a result
of the exercise of such powers, and neither it nor any of its officers,
directors, employees or agents shall be responsible to Pledgor for any act or
failure to act, except for Secured Party's own gross negligence or willful
misconduct.

         Section 13.       REMEDIES. In each case below, subject to the
limitations on enforcement by the Secured Party in clauses 9 and 10 of the STID;

                  13.01.   Remedies upon Default. If an Enforcement Event shall
have occurred and be continuing, Secured Party (acting on instructions received
pursuant to the terms of the STID) may, without notice to or demand upon
Pledgor, declare this Agreement to be in default, and Secured Party shall
thereafter have in any jurisdiction in which enforcement hereof is sought, in
addition to all other rights and remedies, the rights and remedies of a secured
party under the NYUCC or the UCC of any other jurisdiction in which Collateral
is located, including, without limitation, the right to take possession of the
Collateral, and for that purpose Secured Party may, so far as Pledgor can give
authority therefor, enter upon any premises on which the Collateral may be
situated and remove the same therefrom. Secured Party may in its discretion
require Pledgor to assemble all or any part of the Collateral at such location
or locations within the jurisdiction(s) of Pledgor's principal office(s) or at
such other locations as Secured Party may reasonably designate. Unless the
Collateral is perishable or threatens to decline speedily in value or is of a
type customarily sold on a recognized market, Secured Party shall give to
Pledgor at least ten (10) days' prior written notice of the time and place of
any public sale of Collateral or of the time after which any private sale or any
other intended disposition is to be made. Pledgor hereby acknowledges that ten
(10) days' prior written notice of such sale or sales shall be reasonable
notice. In addition, Pledgor waives any and all rights that it may have to a
judicial hearing in advance of the enforcement of any of Secured Party's rights
hereunder, including, without limitation, its right following an Enforcement
Event to take immediate possession of the Collateral and to exercise its rights
with respect thereto. The provisions of Section 9-209 of the NYUCC shall not
apply to any account, chattel paper or payment intangible as to which
notification of assignment has been sent to the account debtor.

<PAGE>

                                                                              16

In addition, Secured Party shall have the right to set off any and all
obligations of Secured Party owing to Pledgor under or pursuant to any Relevant
Document, in respect of Collateral or otherwise, against any and all Secured
Obligations and any and all other obligations under any and all of the Relevant
Documents, or any other instrument or agreement owing by Pledgor or any
affiliate of Pledgor to Secured Party under this Agreement or any of the other
Relevant Documents, regardless of whether any such obligations of Pledgor or any
affiliate of Pledgor is mature or unmature. In the case of unmatured
obligations, Secured Party may estimate the amount thereof in good faith.

         Section 14.       STANDARDS FOR EXERCISING REMEDIES. To the extent that
applicable law imposes duties on Secured Party to exercise remedies in a
commercially reasonable manner, Pledgor acknowledges and agrees (subject to
clause 14 of the STID) that it is not commercially unreasonable for Secured
Party (a) to fail to incur expenses reasonably deemed significant by Secured
Party to prepare Collateral for disposition or otherwise to complete raw
material or work in process into finished goods or other finished products for
disposition or to postpone any such disposition pending any such preparation or
processing; (b) to fail to obtain third party consents for access to Collateral
to be disposed of, or to obtain or, if not required by other law, to fail to
obtain governmental or third party consents for the collection or disposition of
Collateral to be collected or disposed of; (c) to fail to exercise collection
remedies against account debtors or other persons obligated on Collateral or to
remove any Lien on or any adverse claims against Collateral; (d) to exercise
collection remedies against account debtors and other persons obligated on
Collateral directly or through the use of collection agencies and other
collection specialists; (e) to advertise dispositions of Collateral through
publications or media of general circulation, whether or not the Collateral is
of a specialized nature; (f) to contact other persons, whether or not in the
same business as Pledgor, for expressions of interest in acquiring all or any
portion of the Collateral; (g) to hire one or more professional auctioneers to
assist in the disposition of Collateral, whether or not the collateral is of a
specialized nature; (h) to dispose of Collateral by utilizing Internet sites
that provide for the auction of assets of the types included in the Collateral
or that have the reasonable capability of doing so, or that match buyers and
sellers of assets; (i) to dispose of assets in wholesale rather than retail
markets; (j) to disclaim disposition warranties; (k) to purchase insurance or
credit enhancements to insure Secured Party against risks of loss, collection or
disposition of Collateral or to provide to Secured Party a guaranteed return
from the collection or disposition of Collateral; or (l) to the extent deemed
appropriate by Secured Party, to obtain the services of other brokers,
investment bankers, consultants and other professionals to assist Secured Party
in the collection or disposition of any of the Collateral. Pledgor acknowledges
that the purpose of this Section 14 is to provide non-exhaustive indications of
what actions or omissions by Secured Party would not be commercially
unreasonable in Secured Party's exercise of remedies against the Collateral and
that other actions or omissions by Secured Party shall not be deemed
commercially unreasonable solely on account of not being indicated in this
Section 14. Without limiting the foregoing, nothing contained in this Section 14
shall be construed to grant any rights to Pledgor or to impose any duties on
Secured Party that would not have been granted or imposed by this Agreement or
by applicable law in the absence of this Section 14.

         Section 15.       WAIVERS BY PLEDGOR; OBLIGATIONS ABSOLUTE.

                           (a)      Pledgor waives demand, notice, protest,
notice of acceptance of this Agreement, notice of loans made, credit extended,
Collateral received or delivered or other action taken in

<PAGE>

                                                                              17

reliance hereon and all other demands and notices of any description thereof,
all in such manner and at such time or times as Secured Party may deem
advisable. Secured Party shall have no duty as to the collection or protection
of the Collateral or any income thereon, nor as to the preservation of rights
against prior parties, nor as to the preservation of any rights pertaining
thereto beyond the safe custody thereof as set forth in Section 9.02.

                           (b)      All rights of Secured Party hereunder, the
Security Interest and all obligations of Pledgor hereunder shall be absolute and
unconditional irrespective of (i) any lack of validity or enforceability of the
Indentures, the STID or any other Relevant Document, any agreement with respect
to any of the Secured Obligations or any other agreement or instrument relating
to any of the foregoing, (ii) any change in the time, manner or place of payment
of, or in any other term of, all or any of the Secured Obligations, or any other
amendment or waiver of or any consent to any departure from the Indentures, any
other Relevant Document, or any other agreement or instrument, (iii) any
exchange, release or non-perfection of any Lien on other collateral, or any
release or amendment or waiver of or consent under or departure from or any
acceptance of partial payment thereon and or settlement, compromise or
adjustment of any of the Secured Obligations or of any guarantee, securing or
guaranteeing all or any of the Secured Obligations, or (iv) any other
circumstance that might otherwise constitute a defense available to, or a
discharge of, Pledgor in respect of the Secured Obligations or this Agreement.

         Section 16.       MARSHALLING. Secured Party shall not be required to
marshal any present or future collateral security (including but not limited to
this Agreement and the Collateral) for, or other assurances of payment of, the
Secured Obligations or any of them or to resort to such collateral security or
other assurances of payment in any particular order, and all of its rights
hereunder and in respect of such collateral security and other assurances of
payment shall be cumulative and in addition to all other rights, however
existing or arising. To the extent that it lawfully may, Pledgor hereby agrees
that it shall not invoke any law relating to the marshalling of collateral that
might cause delay in or impede the enforcement of Secured Party's rights under
this Agreement or under any other instrument creating or evidencing any of the
Secured Obligations or under which any of the Secured Obligations is outstanding
or by which any of the Secured Obligations is secured or payment thereof is
otherwise assured, and, to the extent that it lawfully may, Pledgor hereby
irrevocably waives the benefits of all such laws.

         Section 17.       PROCEEDS OF DISPOSITIONS. After deducting all
expenses payable by Pledgor, including, without limitation, under Section
21.09(a), and after making any payments required by Sections 9-608(a)(1)(A) or
9-615(a)(1) of the NYUCC, the residue of any proceeds of collection or sale of
the Collateral shall, to the extent actually received in cash, be applied to the
payment of the remaining Secured Obligations in such order or preference as is
provided in the STID, proper allowance and provision being made for any Secured
Obligations not then due or held as additional Collateral. Pledgor shall remain
liable for any deficiency in the payment of the Secured Obligations.

         Section 18.       AMOUNTS DUE HEREUNDER. Until paid, all amounts due
and payable by Pledgor hereunder shall be a debt secured by the Collateral and
shall bear, whether before or after judgment, interest until paid at a rate per
annum set forth in Section 21.09.

<PAGE>

                                                                              18

         Section 19.       TERMINATION. Secured Party shall, at the cost of
Pledgor, release the Lien and cancel the security constituted by this Agreement
and procure the reassignment (to the extent necessary) to Pledgor of the
Collateral in accordance with the terms and subject to the conditions and
circumstances set out in clause 5.3 and clause 5.4 of the STID and without
recourse to, or any representations or warranty by, Secured Party or any of its
nominees.

         Section 20.       REINSTATEMENT. The obligations of Pledgor pursuant to
this Agreement shall continue to be effective or automatically be reinstated, as
the case may be, if at any time payment of any of the Secured Obligations is
rescinded or otherwise must be restored or returned by Secured Party upon the
insolvency, bankruptcy, dissolution, liquidation or reorganization of Pledgor or
any other obligor or otherwise, all as though such payment had not been made.

         Section 21.       MISCELLANEOUS.

                  21.01.   Notices. Except as otherwise provided herein,
whenever it is provided herein that any notice, demand, request, consent,
approval, declaration or other communication shall or may be given to or served
upon any of the parties by any other party, or whenever any of the parties
desires to give and serve upon any other party any communication with respect to
this Agreement, each such notice, demand, request, consent, approval,
declaration or other communication shall be in writing and shall be given in the
manner and to the address, and deemed received, as provided for in clause 20 of
the STID.

                  21.02.   GOVERNING LAW; CONSENT TO JURISDICTION. THIS
AGREEMENT SHALL BE GOVERNED BY, AND SHALL BE CONSTRUED AND ENFORCED IN
ACCORDANCE WITH, THE INTERNAL LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO
CONFLICTS OF LAWS PRINCIPLES (WHICH PRINCIPLES SHALL BE DEEMED TO EXCLUDE
SECTION 5-1401 OF THE NEW YORK GENERAL OBLIGATIONS LAW). Pledgor agrees that any
suit for the enforcement of this Agreement may be brought in the courts of the
State of New York or any federal court sitting therein and consents to the
non-exclusive jurisdiction of such court and to service of process in any such
suit being made upon Pledgor by mail at the address specified set forth below
its name on the signature pages hereof. Pledgor hereby waives any objection that
it may now or hereafter have to the venue of any such suit or any such court or
that such suit is brought in an inconvenient court.

                  21.03.   WAIVER OF JURY TRIAL, ETC. PLEDGOR WAIVES ITS RIGHT
TO A JURY TRIAL WITH RESPECT TO ANY ACTION OR CLAIM ARISING OUT OF ANY
LITIGATION OR DISPUTE DIRECTLY OR INDIRECTLY ARISING OUT OF, UNDER OR IN
CONNECTION WITH THIS AGREEMENT, ANY RIGHTS OR OBLIGATIONS HEREUNDER OR THE
PERFORMANCE OF ANY SUCH RIGHTS OR OBLIGATIONS. Pledgor certifies that neither
Secured Party nor any representative, agent or attorney of Secured Party has
represented, expressly or otherwise, that Secured Party would not, in the event
of litigation, seek to enforce the foregoing waivers and acknowledges that, in
entering into the Indentures and the other Relevant Documents to which Secured
Party is a party, Secured Party is relying upon, among other things, the waivers
and certifications contained in this Section 21.03.

                  21.04.   Counterparts. This Agreement may be executed in two
or more separate counterparts, each of which shall constitute an original and
all of which shall collectively and separately constitute one and the same
agreement.

<PAGE>

                                                                              19

                  21.05.   Headings. The headings of each section of this
Agreement are for convenience only and shall not define or limit the provisions
thereof.

                  21.06.   No Strict Construction. The parties hereto have
participated jointly in the negotiation and drafting of this Agreement. In the
event an ambiguity or question of intent or interpretation arises, this
Agreement shall be construed as if drafted jointly by the parties hereto and no
presumption or burden of proof shall arise favoring or disfavoring any party by
virtue of the authorship of any provisions of this Agreement.

                  21.07.   Severability. In the event any one or more of the
provisions contained in this Agreement should be held invalid, illegal or
unenforceable in any respect, the validity, legality and enforceability of the
remaining provisions contained herein shall not in any way be affected or
impaired thereby (it being understood that the invalidity of a particular
provision in a particular jurisdiction shall not in and of itself affect the
validity of such provision in any other jurisdiction).

                  21.08.   Survival of Agreement. All covenants, agreements,
representations and warranties made by Pledgor herein and in the certificates or
other instruments prepared or delivered in connection with or pursuant to this
Agreement shall be considered to have been relied upon by Secured Party and
shall survive the execution and delivery of the Indentures, regardless of any
investigation made by Secured Party, and shall continue in full force and effect
until this Agreement shall terminate (or thereafter to the extent provided
herein).

                  21.09.   Fees and Expenses; Taxes; Indemnification.

                           (a)      Pledgor shall, from time to time and
promptly on demand by Secured Party reimburse to Secured Party all costs and
expenses (including legal fees) on a full indemnity basis together with any
applicable VAT incurred by Secured Party (provided that in relation to clause
(i) of this Section 21.09(a), such costs and expenses must be properly incurred)
in connection with:

                                    (i)      the execution, release and
discharge of this Agreement and the Security created or intended to be created
in respect of the Collateral and perfection of the Security Interest
contemplated in this Agreement or in any such documents or forming part of the
Security Interest created or intended to be created in respect of the
Collateral;

                                    (ii)     the actual or contemplated
exercise, preservation and/or enforcement of any of the rights, powers and
remedies of, or the performance of the duties and obligations of, Secured Party,
or any amendment or waiver in respect of this Agreement;

                                    (iii)    the foreclosure of any Collateral;
and

                                    (iv)     the preservation and/or enforcement
of the Security created or intended to be created in respect of the Collateral;

the amount of which costs and expenses shall carry interest from the date of
such demand until so reimbursed at the rate and on the basis set forth in clause
18.4.1 of the STID.

                           (b)      Pledgor shall pay, promptly on demand of
Secured Party all stamp, registration, notarial and other similar Taxes or fees
paid or payable by Secured Party in connection with any action taken or
contemplated by or on behalf of Secured Party for perfecting, enforcing,
releasing,

<PAGE>

                                                                              20

cancelling, reassigning or resolving any doubt concerning, or for any other
purpose in relation to this Agreement, any amendment thereto, any transfer
and/or assignment of the rights and/or obligations under the same or the
Security Interest created or intended to be created in respect of the Collateral
and shall, from time to time, indemnify Secured Party promptly on demand against
any liabilities, costs, claims and expenses resulting from any failure to pay by
Pledgor or any delay by Pledgor in paying any such Taxes or fees.

                           (c)      Clause 19 of the STID is hereby incorporated
herein by this reference with the same effect as though set forth in its
entirety herein, as if Pledgor were "Issuer" under such clause.

                           (d)      Any such amounts payable as provided
hereunder shall be additional Secured Obligations secured hereby. The provisions
of this Section 21.09 shall remain operative and in full force and effect
regardless of the termination of this Agreement, the consummation of the
transactions contemplated hereby, the repayment of any of the Notes, the
invalidity or unenforceability of any term or provision of this Agreement or the
STID, or any investigation made by or on behalf of Secured Party. All amounts
due under this Section 21.09 shall be payable on written demand therefor.

                  21.10.   Matters Relating to Secured Party. Each of Clauses
14, 15 and 16 of the STID is hereby incorporated herein by this reference with
the same effect as though set forth in its entirety herein.

                  21.11.   Binding Effect; Several Agreement. This Agreement is
binding upon Pledgor and Secured Party and their respective successors and
permitted assigns, and shall inure to the benefit of Pledgor, Secured Party and
their respective successors and permitted assigns, except that Pledgor shall
have no right to assign or transfer its rights or obligations hereunder or any
interest herein (and any such assignment or transfer shall be void) except as
expressly contemplated by this Agreement or the Indentures. Secured Party may
assign and transfer all or any of its rights and obligations under this
Agreement in accordance with the STID, and Secured Party shall be entitled to
disclose such information concerning the Pledgor and this Agreement as the
Secured Party considers appropriate to any actual or proposed direct or indirect
successor or to any person to whom information may be required to be disclosed
by applicable law.

                  21.12.   Waivers; Amendment.

                           (a)      No failure or delay of Secured Party in
exercising any power or right hereunder shall operate as a waiver thereof, nor
shall any single or partial exercise of any such right or power, or any
abandonment or discontinuance of steps to enforce such a right or power,
preclude any other or further exercise thereof or the exercise of any other
right or power. The rights and remedies of Secured Party hereunder and under the
STID are cumulative and are not exclusive of any rights or remedies that they
would otherwise have. No waiver of any provisions of this Agreement or consent
to any departure by Pledgor therefrom shall in any event be effective unless the
same shall be permitted by paragraph (b) below, and then such waiver or consent
shall be effective only in the specific instance and for the purpose for which
given. No notice to or demand on Pledgor in any case shall entitle Pledgor to
any other or further notice or demand in similar or other circumstances.

                           (b)      Neither this Agreement nor any provision
hereof may be waived, amended or modified except pursuant to an agreement or
agreements in writing entered into by the

<PAGE>

                                                                              21

Secured Party and Pledgor, subject to any consent required in accordance with
the Indentures and the STID.

                   [the rest of this page intentionally blank]

<PAGE>

                                                                              22

IN WITNESS WHEREOF, intending to be legally bound, Pledgor has caused this
Security Agreement to be duly executed as of the date first above written.

MARCONI INTELLECTUAL PROPERTY (RINGFENCE) INC.

By:      T.R.C. SHEPHERD
         Name: T.R.C. SHEPHERD
         Title: ATTORNEY

Address for New York service of process:

Marconi Electronic Systems Holdings Inc.
c/o Marconi Communications, Inc.
333 Pierce Road - Suite 370
Itasca, Illinois 60143 USA
Attention:  Patricia Hoffman
Telecopier No.:  (630) 285-1514

ACCEPTED AND AGREED:

THE LAW DEBENTURE TRUST CORPORATION p.l.c.

as Secured Party

By:  R.D. RANCE
         Name: R.D. RANCE
         Title: DIRECTOR

<PAGE>

                                                                    Exhibit A to
                                                              Security Agreement

                             PERFECTION CERTIFICATE

Reference is made to the Security Agreement dated as of May 19TH, 2003 (the
"SECURITY AGREEMENT") between Marconi Intellectual Property (Ringfence) Inc., a
corporation (the "GRANTOR") and The Law Debenture Trust Corporation p.l.c. as
Security Trustee (the "SECURED PARTY"). Capitalized terms used herein without
definition shall have the respective meanings assigned to such terms in the
Security Agreement.

The undersigned, an Authorized Signatory of the Grantor, hereby certifies to the
Secured Party as follows:

1.   NAME. The exact legal name of the Grantor as that name appears on its
         Certificate of Incorporation is as follows:

         Marconi Intellectual Property (Ringfence) Inc.

         (Source: Uniform Commercial Code ("UCC") Section 9-503(a).)

2.   OTHER IDENTIFYING FACTORS.

         (a)           The following is the mailing address of the Grantor:

         c/o Marconi Communications, Inc.
         3000 Marconi Drive
         Warrendale, PA 15086

         (Source: UCC Section 9-516(b)(5)(A).)

         (b)           If different from its mailing address, the Grantor's
         place of business or, if the Grantor has more than one place of
         business, its chief executive office, is located at the following
         address:

<TABLE>
<CAPTION>
Address                    County                       State
-------                    ------                       -----
<S>                        <C>                          <C>
None
</TABLE>

         (Source: UCC Sections 9-301(a) and 9-307; former UCC Sections 9-103(3),
         9-103(4), 9-401(6).)

         (c)           The following is the type of organization of the Grantor:

         Corporation

                                      C-1

<PAGE>

         (Source: UCC Section 9-516(b)(5)(C).)

         (d)           The following is the jurisdiction of the Grantor's
         organization:

         Delaware

         (Source: UCC Section 9-516(b)(5)(C).)

         (e)           The following is the Grantor's state-issued
         organizational identification number:

         3624248

         (Source: UCC Section 9-516(b)(5)(C).)

3.       OTHER CURRENT LOCATIONS.

         (a)           The following are all other locations in the United
                  States of America in which the Grantor maintains any books or
                  records relating to any of the Collateral consisting of
                  accounts, instruments, chattel paper, general intangibles or
                  mobile goods:

<TABLE>
<CAPTION>
Address                    County                       State
-------                    ------                       -----
<S>                        <C>                          <C>
None.
</TABLE>

         (Source: UCC Sections 9-301(b) and (c); former UCC Sections 9-103(3),
         9-103(4), 9-401(6).)

         (b)           The following are all other places of business of the
                  Grantor in the United States of America where any of the
                  Collateral consisting of inventory or equipment is located:

<TABLE>
<CAPTION>
Address                    County                       State
-------                    ------                       -----
<S>                        <C>                          <C>
None.
</TABLE>

         (Source: UCC Sections 9-301(b) and (c); former UCC Sections 9-103(1).

         (c)           The following are the names and addresses of all persons
                  or entities other than the Grantor, such as lessees,
                  consignees, processors, warehousemen or purchasers of chattel
                  paper, which persons or entities have possession or are
                  intended to have possession of any of the Collateral
                  consisting of instruments, chattel paper, inventory or
                  equipment and the nature of such possession if the Collateral
                  is held by such person or entity for more than 90 days and has
                  a book or face value, as the cased may be, equal to or greater
                  than $5,000,000 (five million dollars).

                                      C-2

<PAGE>

                  None.

                                      C-3

<PAGE>

4.   INTELLECTUAL PROPERTY. Attached hereto as Schedule 4A is a schedule setting
         forth all of the Grantor's Patents, Patent Licenses, Trademarks and
         Trademark Licenses, including the registration number and the
         expiration date of each Patent, Patent License, Trademark and Trademark
         License owned by the Grantor. Attached hereto as Schedule 4B is a
         schedule setting forth all of the Grantor's Copyrights and Copyright
         Licenses, including the registration number and the expiration date of
         each Copyright or Copyright License owned by the Grantor.

5.   UNUSUAL TRANSACTIONS. Except for those purchases, acquisitions and other
         transactions described on Schedule 3 or on Schedule 8 attached hereto,
         all of the Collateral has been originated by the Grantor in the
         ordinary course of the Grantor's business or consists of goods that
         have been acquired by the Grantor in the ordinary course from a person
         in the business of selling goods of that kind.

         None.

         (Source: UCC Sections 9-102(a)(64), 9-203(f), 9-301(b), 9-315(a) and
         9-316; former UCC Sections 1-201(9), 9-306(2) and 9-402(7) (third
         sentence); see also former UCC Section 9-301(1)(c).)

6.   UCC FILINGS. Attached hereto as Schedule 6 is a copy of financing statement
         filed or to be filed in the central UCC filing office in the
         jurisdiction identified in ss.2(d) and in each real estate recording
         office referred to on Schedule 6 hereto.

7.   SCHEDULE OF FILING. Attached hereto as Schedule 7 is a schedule setting
         forth filing information with respect to the filings described in
         Section 7.

8.   STOCK OWNERSHIP AND OTHER EQUITY INTERESTS. Attached hereto as Schedule 8
         is a true and correct list of each equity investment of the Grantor.

9.   DEBT INSTRUMENTS. Attached hereto as Schedule 9 is a true and correct list
         of all promissory notes and other evidence of indebtedness held by the
         Grantor including all intercompany notes, that have a book or face
         value, as the case may be, equal to or greater than $5,000,000 (five
         million dollars), and additionally for letters of credit, with a term
         of 90 days or longer.

IN WITNESS WHEREOF, I have hereunto signed this Certificate on May 19TH, 2003.

T.C.R. SHEPHERD
Name:  T.C.R. SHEPHERD
Title: ATTORNEY

                                      C-4

<PAGE>

                                   SCHEDULE 4A

<TABLE>
<CAPTION>
Case Reference            Application Number        Patent Number
<S>                       <C>                       <C>
P/62022.USA                  07/861272                 5825765
P/62023.USA                  07/930081                 5323389
P/62023.USC                  08/261427                 5479401
P/62023.USC1                 08/577917                 5689512
P/62024.EPP                  96308232.6
P/62024.J PP                 HEI 8-307836
P/62024.USP                  08/559610                 5870584
P/62025.CA1                  2151180
P/62025.CAP                  2151181                   2151181
P/62025.EP1                  95306291.6
P/62025.EPP                  95306292.4
P/62025.JP1                  HEI 7-234260
P/62025.JPP                  HEI 7-234247              3-230957
P/62025.MX1                  953210                    197267
P/62025. MXP                 953208
P/62025.USA                  08/305576                 5528588
P/62025.USCIP                08/330381                 5875189
P/62026.CA1                  2150967
P/62026.CAP                  2150966                   2150966
P/62026. EP1                 95309416.6
P/62026.EPP                  95309404.2
P/62026.JP1                  HEI 7-296877
P/62026.JPP                  HEI 7-296780
P/62026. MX1                 953209                    196805
P/62026. MXP                 953207                    196804
P/62026.USA                  08/362217                 5828879
P/62026.USCIP                08/375624                 5845115
P/62026.USCIP1               08/476365                 5828878
P/62027.CAP                  2152714                   2152714
P/62027.EPP                  96300672.1
P/62027.JPP                  HEI 8-4448
P/62027.KRP                  206211996
P/62027.MXP                  954679                    191997
P/62027.USA                  08/381110                 5541918
P/62027.USCIP                08/687888                 6278711
P/62027.USCIP1               09/916016
P/62028.CAP                  2152710
P/62028.EPP                  96300671.3
P/62028.JPP                  HEI 8-4456
P/62028.MXP                  954680                    193997
P/62028.USA                  08/381112                 5548588
P/62028.USC                  08/693996                 6108335
P/62029.USA                  08/621809                 5974053
P/62031.EPP                  97305767.2
P/62031.JPP                  HEI 9-209308
P/62031.USA                  08/692007                 5966380
P/62032.EPP                  96303586.0                0744850
</TABLE>

                                      C-5

<PAGE>

<TABLE>
<S>                          <C>                       <C>
P/62032.JPP                  HEI 8-127481
P/62032.USA                  08/445673                 5936939
P/62033.USA                  08/917392                 6412005
P/62035.EPP                  97308129.2
P/62035.JPP                  HEI 9-282348
P/62035.USA                  08/730446                 5960088
P/62036.USA                  08/851881                 6310879
P/62037.EPP                  98305703.5
P/62037.USA                  08/895353                 6003062
P/62038.USA                  08/874608                 6208652
P/62039.USA                  09/008406                 6094687
P/62040.EPP                  97302318.7
P/62040.JPP                  HEI 9-88551
P/62040.USA                  08/628206                 5995511
P/62041.EPP                  97302955.6
P/62041.JPP                  HEI 9-114797
P/62041.USA                  08/641916                 5935213
P/62043.USA                  08/996828                 6282171
P/62044.USA                  08/971170                 6151321
P/62045.USA                  08/970636                 6026090
P/62046.USA                  08/970635                 6192033
P/62047.USA                  09/126975                 6216182
P/62048.USA                  09/079589                 6320861
P/62049.USA                  09/103042                 6404768
P/62050.USA                  09/025928                 6301251
P/62051.USA                  08/960672
P/62052.EPP                  99305817.1
P/62052.JPP                  HEI 11-207393
P/62052.USA                  09/120697                 6122673
P/62053.EPP                  99030600.9
P/62053.JPP                  HEI 11-217366
P/62053.USA                  09/126475                 6345040
P/62054.EPP                  99306201.7
P/62054.JPP                  HEI 11-220626
P/62054.USA                  09/129284                 6456592
P/62055.EPP                  99030680.8
P/62055.JPP                  HEI 11-239310
P/62055.USA                  09/140923
P/62056.USA                  09/417038
P/62057.EPP                  99305824.7
P/62057.JPP                  11-205561
P/62057.USP                  09/282748
P/62058.EPP                  99030620.3
P/62058.JPP                  HEI 11-226119
P/62058.USA                  09/135093
P/62059.EPP                  00302447.8
P/62059.JPP                  2000-93705
P/62059.USA                  09/282980
P/62060.EPP                  99308255.1
P/62060.JPP                  HEI 11-299464
P/62060.USA                  09/176703
P/62061.EPP                  00302910.5
</TABLE>

                                      C-6

<PAGE>

<TABLE>
<S>                          <C>                       <C>
P/62061.JPP                  2000-113100
P/62061.USA                  09/293563
P/62062.USA                  09/137791
P/62063.EPP                  99308410.2
P/62063APP                   HEI 11-303421
P/62063.USA                  09/179030
P/62064.JPP                  2000-105698
P/62064.USA                  09/255197
P/62065.USA                  09/177217
P/62066.EPP                  00304944.2
P/62066.JPP                  2000-176235
P/62066.USA                  09/333450
P/62067.USA                  09/315575
P/62069.USA                  09/315275
P/62072.EPP                  01030114.3
P/62072.JPP                  2001-36585
P/62072.USA                  09/503673
P/62074.USA                  09/356086
P/62075.USA                  09/499819
P/62403.USA                  09/499859
P/63038.USA                  09/570672
P/63076.EPP                  01950718.5
P/63076.JPP                  2002-508171
P/63076.USA                  09/608771                 6477166
P/63077.EPP                  01950746.6
P/63077.JPP                  2002-507555
P/63077.USA                  09/608241                 6463063
P/63078.EPP                  01948824.6
P/63078.JPP                  2002-507581
P/63078.USA                  09/609298                 6473435
P/63079.EPP                  01948819.6
P/63079.JPP                  2002-507551
P/63079.USA                  09/607763                 6526024
P/63080.USA                  09/610116
P/63081.EPP                  01950646.8
P/63081.JPP                  2002-507553
P/63081.USA                  09/609177
P/63082.EPP                  01950691.4
P/63082.JPP                  2002-507580
P/63082.USA                  09/609497                 6473433
P/63083.EPP                  01950644.3
P/63083.JPP                  2002-507552
P/63083.USA                  09/609653
P/63123.EPP                  01306304.5
P/63123.JPP                  2001-223986
P/63123.USA                  09/627800
P/63124.EPP                  01306819.2
P/63124.JPP                  2001-241632
P/63124.USA                  09/637049
P/63125.USA                  09/628059
P/63126.USA                  09/627926
P/63127.EPP                  01306317.7
</TABLE>

                                      C-7

<PAGE>

<TABLE>
<S>                          <C>                       <C>
P/63127.JPP                  2001-225569
P/63127.USA                  09/627924
P/63128.EPP                  01306823.4
P/63128.JPP                  2001-241480
P/63128.USA                  09/637047
P/63129.USA                  09/637041
P/63167.USA                  09/678827
P/63168.USA                  09/730195
P/63169.USA                  09/686768
P/63170.USA                  09/686539
P/63199.EPP                  01309949.4
P/63199.JPP                  2001-365577
P/63199.USA                  09/728880
P/63200.USA                  09/730211
P/63201.EPP                  01310363.3
P/63201.JPP                  2001-382459
P/63201.USA                  09/740151
P/63338.EPP                  02253756.7
P/63338.USA                  09/874726                 6549695
P/63341.USA                  09/833159
P/63341.WOP                  IB02/02179
P/63349.USA                  09/847609
P/63385.USA                  09/866950
P/63692.USP                  08/879829                 6118782
P/63707.USA                  10/073573
P/63709.USA                  10/115323
P/63709.WOP                  IB03/01688
P/63710.USA                  10/073572
P/63711.USA                  10/114402
P/63711.WOP                  IB03/01468
P/63802.USA                  10/263598
P/63712.USA                  08/414771                 5557506
P/63712.USC                  08/709038                 5689406
P/62078.USA                  08/093397                 5515376
P/62077.USA                  489411                    5608892
P/62077.USC                  081799636                 5875466
P/62078.USD                  08/358211                 5610905
P/62079.USA                  304053                    5237670
P/62079.USC                  276877                    5444858
P/62079.USC1                 473035                    5586299
P/62079.USD                  964182                    5313594
P/62079.USD1                 359112                    5577229
P/62080.USA                  08/465164                 5726506
P/62064.EPP                  00301399.2
P/62076.USA                  08/561365                 5892932
P/62078.EPP                  94921361.5
P/62078.HKP                  98115744.0
P/62078.JPP                  7-505151                  3335358
P/62078.USD1                 08/713046
P/62110.USP                  09/620519                 6315270
P/62121.USA                  09/085854                 5982610
P/61837.USA                  09/203409                 6362908
</TABLE>

                                      C-8

<PAGE>

<TABLE>
<S>                          <C>                       <C>
P/61839.USA                  09/164495
P/61840.USA                  09/375312                 6366464
P/61841.CAP                  2343241
P/61841.USA                  09/150817
P/61842.USP                  09/237984                 6108183
P/61843.USA                  09/286055                 6169389
P/61844.USA                  09/249733                 6535308
P/61845.CAP                  2362746
P/61845.EPP                  00913391.9
P/61845.USA                  09/249055                 6496639
P/61846.EPP                  00961315.9
P/61846.EPP1

P/61846.USA                  09/309717                 6460182
P/61846.USC                  09/879395
P/61846.USC1                 09/932867
P/61846.USCIP                09/633320
P/61848.BRP                  9911360-0
P/61848.CAP                  2334927
P/61848.EPP                  99928842.6
P/61848.MXP                  012545
P/61848.USA                  09/100392                 6353609
P/61848.USC                  09/992649
P/61851.CAP                  577405                    1288534
P/61851.USA                  07/111215                 4767980
P/61852.USC                  07/250974                 4876630
P/61853.CAP                  590153                    1299790
P/61853.USA                  07/265718                 4903292
P/61855.CAP                  612336                    1340124
P/61855.USA                  07/264356                 4958926
P/61857.USA                  07/411727                 5022752
P/61858.CAP                  592917                    1315904
P/61858.USC                  07/547430                 5046067
P/61859.CAP                  600812                    1331478
P/61859.USC                  07/504049                 5050210
P/61860.USA                  07/541577                 5067810
P/61861.USA                  07/621536                 5146476
P/61862.USA                  07/461814                 5155746
P/61863.USA                  07/624860                 5260996
P/61865.USA                  08/298146                 5515433
P/61866.USA                  08/328904                 5505636
P/61871.USA                  09/130734                 6288883
P/61872.USA                  09/305637                 6151226
P/61873.BRP                  9807545-4
P/61873.CAP                  2279343
P/61873.EPP                  98903882.3
P/61873.MXP                  997141
P/61873.USC                  10/176542
P/61873.USCIP                09/325619                 6466572
P/61874.USA                  09/277705                 6322400
P/61875DEP                   00957238.9                1173939
P/61875.FRP                  00957238.9                1173939
P/61875.GBP                  00957238.9                1173939
</TABLE>

                                      C-9

<PAGE>

<TABLE>
<S>                          <C>                       <C>
P/61875.ITP                  00957238.9                1173939
P/61875.NLP                  00957238.9                1173939
P/61875.SEP                  00957238.9                1173939
P/61875.USA                  09/300880                 6246510
P/61877.USA                  09/305579                 6278829
P/61879.USA                  06/526119                 4546322
P/62013.EPP                  00930824.8
P/62013.USC                  09/947154                 6542382
P/62013.USP                  09/410975                 6310784
P/62014.EPP                  00930823.0
P/62014.USC                  10/195087
P/62018.CAP                  2316550
P/62018.USA                  09/388630                 6385030
P/62111.CAP                  2319936
P/62111.USA                  09/411024                 6195494
P/62112.USA                  09/474640                 6256205
P/62113.CAP                  2319989
P/62113.USA                  09/415362                 6396673
P/62114.CAP                  2327318
P/62114.USA                  09/476079                 6418195
P/63347.EPP                  02253954.8
P/63347.USA                  09/876439
P/63386.USA                  09/532996                 6366717
P/63387.USA                  09/540956                 6366712
P/63388.USA                  09/536047
P/63389.USA                  09/520587                 6427045
P/63390.USA                  09/516535                 6316722
P/63391.USA                  09/520082                 6466728
P/63393.USA                  09/539395
P/63394.CAP                  2373323
P/63394.EPP                  01914793.3
P/63394.USA                  09/537022
P/63394.USP                  09/794869
P/63395.USA                  09/540955
P/63396.USA                  09/587879                 6548753
P/63397.USA                  09/684757
P/63398.USA                  09/662475
P/63400.EPP                  01125899.3
P/63400.USA                  09/703069
P/63402.USA                  09/684756
P/63403.USA                  09/684755
P/63406.USA                  09/703114                 6442035
P/63407.EPP                  01128041.9
P/63407.USA                  09/723885
P/63409.USA                  09/703115
P/63410.EPP                  01128040.1
P/63410.USA                  091723804
P/63411.USCIP                10/200924
P/63412.USP                  10/199549
P/63412.WOP                  IB02/03393
P/63413.USP                  10/200534
P/63417.US1                  60/403804
</TABLE>

                                      C-10

<PAGE>

<TABLE>
<S>                          <C>                       <C>
P/63484.CAP                  2384190
P/63484.EPP                  00971041.9
P/63754.USP                  10/199566
P/63754.WOP                  IB02/03394
P/63756.USP                  10/283527
P/63758.US1                  60/415064
P/63759.US1                  60/431467
P/63760.US2                  60/437789
P/63761.USP
P/63762.USA                  60/374867
P/61883.USA                  06/854532                 4661651
P/61884.USA                  06/711384                 4665546
P/61885.CAP                  523396                    1287871
P/61885.USA                  06/804056                 4680665
P/61887.MXP                  204690                    157911
P/61887.USC                  06/901964                 4808116
P/61887.USCIP                07/008055                 4752249
P/61888.USA                  07/039653                 4827502
P/61889.USA                  07/202226                 4854884
P/61890.CAP                  609187                    1331479
P/61890.USA                  07/281492                 4876621
P/61891.USA                  07202702                  4876626
P/61894.USA                  07/314268                 4901202
P/61895.USA                  07/282003                 4907120
P/61897.CAP                  1304463                   1304463
P/61897.USA                  07/330621                 4919622
P/61898.USA                  07/426791                 4958253
P/61903.USA                  07/590669                 5093887
P/61904.USA                  07/735104                 5117067
P/61906.USA                  07/518541                 5127845
P/61907.USA                  07/735426                 5127851
P/61909.USA                  07/680767                 5136463
P/61910.CAP                  2055029
P/61910.USA                  07/721257                 5139440
P/61911.USA                  07/665660                 5195015
P/61914.USCIP                07/735285                 5235134
P/61916.USA                  08/052061                 5302137
P/61917.USA                  07/960950                 5341270
P/61918.USA                  08/127895                 5451170
P/61920.USA                  08/237008                 5514005
P/61921.USA                  08/253391                 5523916
P/61922.USA                  08/438691                 5553394
P/61923.USA                  08/388401                 5575680
P/61924.USA                  08/595278                 5751533
P/61926.CAP                  2371374
P/61926.USA                  09/295643                 6119768
P/61927.USA                  06/591771                 4563053
P/61928.USD                  06/751442                 4604888
P/61929.USC                  06/871138                 4646395
P/61930.JPP                  61-246504                 2014184
P/61930.KRP                  86-8750                   135089
P/61930.USA                  06/789084                 4652070
</TABLE>

                                      C-11

<PAGE>

<TABLE>
<S>                          <C>                       <C>
P/61931.USA                  06/708217                 4605275
P/61933.CAP                  2315581
P/61933.USA                  09/366982                 6198041
P/61934.CAP                  2316506
P/61934.USA                  09/397441                 6182846
P/61941.AUP                  73647/96                  699921
P/61941.CAP                  2229571
P/61941.GBP                  96935863.9                0852827
P/61941.ILP                  119285                    119285
P/61941.INP                  1636/MAS/96
P/61941.MXP                  981652                    203927
P/61941.SEP                  96935863.9                0852827
P/61941.USA                  08/536062                 5779504
P/61942.CAP                  2316572
P/61942.USA                  09/394148                 6244634
P/61943.CAP                  2316507
P/61943.USA                  09/382942                 6252166
P/61944.CAP                  449502                    1216622
P/61944.GBP                  8407104.2                 2137032
P/61944.TW P                 7311148                   27611
P/62115.USA                  08/825144                 6039578
P/63304.CLP                  0691-2001
P/63304.PHP                  1-2001-0756
P/63304.THP                  64628
P/63304.USA                  09/537021                 6254404
P/63306.USA                  09/665462                 6364007
P/63307.USA                  09/664624
P/63311.USA                  09/725539                 6401463
P/63311.MOP                  US01/44219
P/63313.USA                  091766766                 6501015
P/63314.USA                  09/824490
P/63317.CAP                  2392646
P/63317.USA                  09/900270                 6462269
P/63317.WOP                  US02/20355
P/63318.CAP                  2393319
P/63318.USA                  09/910597                 6455772
P/63318.WOP                  US02/20356
P/63319.CAP                  2380878
P/63319.USA                  09/827678
P/63320.CAP                  2371553
P/63320.USA                  09/782831
P/63322.USA                  10/047871
P/63322.WOP                  US03/00457
P/63325.USA                  09/817862
P/63340.USA                  06/659580                 4702551
P/63342.USA                  09/514071                 6238234
P/63343.USA                  09/664655                 6317320
P/63344.CAP                  2316563
P/63344.USA                  09/548043
P/63346.USA                  09/567528
P/63350.USA                  09/543483                 6476519
P/63351.USC                  08/926234                 5936822
</TABLE>

                                      C-12

<PAGE>

<TABLE>
<S>                          <C>                       <C>
P/63352.USA                  09/020794                 5953195
P/63353.CAP                  2244582                   2244582
P/63353.USA                  08/907700                 5874698
P/63354.USA                  09/041182                 5961340
P/63355.USA                  08/980961                 5991136
P/63356.USA                  09/025138                 6063152
P/63357.USA                  08/949829                 6104921
P/63358.USA                  09/030564                 6142817
P/63358.USP                  09/548038
P/63359.USP                  08/948973                 6074240
P/63359.VEP                  2070-97                   unknown
P/63392.CAP                  2357642
P/63720.USA                  09/882655                 6345512
P/63720.WOP                  US02/18921
P/63725.USA                  10/038637
P/63727.USA                  10/114145
P/63729.USA                  10/335120
P/63909.USA                  10/114138
P/61945.USA                  07/029216                 4727469
P/61946.USD                  07/140874                 4761727
P/61947.USA                  07/242558                 4831507
P/61948.USC                  07/265327                 4855890
P/61949.USA                  07/496068                 4955053
P/61950.USA                  07/693561                 5122945
P/61951.USA                  07/553228                 5180962
P/61952.USA                  08/260524                 5563775
P/61953.USA                  08/567299                 5654661
P/61954.USA                  08/576784                 5640059
P/61955.USA                  08/576620                 5619405
P/61956.USA                  08/260767                 5610508
P/61957.USA                  08/241176                 5559487
P/61958.USA                  08/225909                 5517755
P/61959.USA                  08/717482                 5726852
P/61960.USA                  08/607239                 5706157
P/61960.USC                  09/782122                 6449136
P/61960.USD                  09/630715                 6362943
P/61960.USP                  09/480797                 6215633
P/61970.USA                  08/726318                 5815389
P/62117.USA                  08/696505                 5930123
P/62118.USA                  08/827235                 5923548
P/62119.USA                  08/827234                 5864471
P/62120.USA                  08/854894                 5901033
P/62122.USA                  09/087241                 5986558
P/63380.USP                  09/726364                 6414245
P/63381.USA                  09/618085                 6492745
P/63382.CAP                  CAXXX004
P/63382.MXP                  PA/a/2002/01099
P/63382.USP                  091766351                 6498491
P/63383.USA                  09/703016                 6358099
P/63384.CAP                  US01/48398
P/63384.USA                  091703120                 6359770
P/63384.WOP                  US01/48398
</TABLE>

                                      C-13

<PAGE>

<TABLE>
<S>                          <C>                       <C>
P/63483.USP                  09/709843                 6349837
P/63535.CAP                  2415079
P/63535.MXP                  PA/a20030004O
P/63535.USA                  09/861148
P/63535.WOP                  US02/14283
P/63536.CAP                  2416047
P/63536.MXP                  PA/a/2003/00042
P/63536.USA                  09/861204
P/63536.WOP                  US02/14284
P/63540.CAP                  2415235
P/63540.MXP                  MXXXX001
P/63540.USP                  10/152883
P/63540.WOP                  US02/16121
P/61974.AUP                  51577/00                  751936
P/61974.CAP                  2375818
P/61974.EPP                  00936231.0
P/61974.USA                  09/324244
P/61975.CAP                  US00/20890
P/61975.EPP                  00953767.1
P/61975.JPP                  2001-518969
P/61975.USA                  09/378844
P/61977.CAP                  2401051
P/61977.EPP                  00992503.3
P/61977.USA                  09/514032
P/63362.USA                  09/632952                 6362670
P/63363.USA                  09/620404                 6489852
P/63364.CAP                  2417666
P/63364.EPP                  01952956.9
P/63364.USP                  09/721230
P/63365.USA                  09/625698                 6313708
P/63366.USA                  09/618882                 6304115
P/63366.USC                  09/943590                 6466068
P/63367.CAP                  2399920
P/63367.EPP                  02256057.7
P/63367.USA                  09/943147
P/63369.EPP                  01988299.2
P/63369.USP                  09/817993
P/63369.WOP                  US01/48047
P/63370.EPP                  01990075.2
P/63370.USP                  09/817982
P/63370.WOP                  US01/47605
P/63372.USA                  09/630791
P/63373.USP                  09/920423
P/63374.USP                  09/921835
P/63375.USP                  09/921834
P/63376.USP                  09/908001
P/63377.CAP                  2412430
P/63377.EPP                  01942109.8
P/63377.USP                  09/875723
P/63731.USP                  10/163828
P/63731.WOP                  US02/17921
P/63732.USP                  10/164180
</TABLE>

                                      C-14

<PAGE>

<TABLE>
<S>                          <C>                       <C>
P/63732.WOP                  US02/18061
P/63733.USP                  10/163760
P/63741.USP                  10/163731
P/63747.USP                  10/267478
P/63750.EPP                  EPXXXX01
P/63750.USP                  USXXXX01
P/63810.USA                  60/394403
P/61864.USA                  07/944204                 5473666
P/61864.USD                  08/566898                 5640433
P/61864.USD1                 08/567140                 5652712
P/62076.EPP                  96939590.4
P/62076.JPP                  HEI9-519760
</TABLE>

                                      C-15

<PAGE>

                                   SCHEDULE 4B

                                      None.

                                      C-16

<PAGE>

                                   SCHEDULE 5

                                      None.

                                      C-17

<PAGE>

                                   SCHEDULE 6

                                      C-18

<PAGE>

                                   SCHEDULE 7

                                      C-19

<PAGE>

                                   SCHEDULE 8

                                      None.

                                      C-20

<PAGE>

                                   SCHEDULE 9

                                      None.

                                      C-21

<PAGE>

                                                                    EXHIBIT B TO
                                                              SECURITY AGREEMENT

                        SUPPLEMENT TO SECURITY AGREEMENT

                                  (COPYRIGHTS)

WHEREAS, MARCONI INTELLECTUAL PROPERTY (RINGFENCE) INC., a Delaware corporation
(herein referred to as "PLEDGOR"), having an address at c/o Marconi
Communications, Inc., 3000 Marconi Drive, Warrendale, PA 15086, has adopted,
used and is using the copyrights listed on the annexed Schedule 1-A, which
copyrights are registered in the United States Copyright Office (the
"COPYRIGHTS");

WHEREAS, the Pledgor has entered into a Security Agreement dated as of May 19,
2003 (said Security Agreement, as it may hereafter be amended or otherwise
modified from time to time being the "SECURITY AGREEMENT", the terms defined
therein and not otherwise defined herein being used herein as therein defined)
in favor of the Secured Party; and

WHEREAS, pursuant to the Security Agreement, the Pledgor has granted to Secured
Party a security interest in all right, title and interest of the Pledgor in and
to the Copyrights, and the registrations and recordings thereof in the United
States Copyright Office or any other country or any political subdivision
thereof, all whether now or hereafter owned or licensable by the Pledgor and all
extensions or renewals thereof and all Copyright Licenses, and all proceeds of
all of the foregoing, including, without limitation, any claims by the Pledgor
against third parties for infringement thereof (the "COLLATERAL"), to secure the
payment and performance of the Secured Obligations.

NOW, THEREFORE, for good and valuable consideration, receipt of which is hereby
acknowledged, the Pledgor does hereby further confirm, and put on the public
record, its grant to Secured Party of a security interest in and mortgage on the
Collateral to secure the prompt payment and performance of the Secured
Obligations.

The Pledgor does hereby further acknowledge and affirm that the rights and
remedies of Secured Party with respect to the assignment of and grant of a
security interest in the Collateral made hereby are more fully set forth in the
Security Agreement, the terms and provisions of which are hereby incorporated
herein by reference as if fully set forth herein.

Secured Party's address is 5th Floor, 100 Wood Street, London, EC2V 7EX, United
Kingdom.

                                      C-22

<PAGE>

IN WITNESS WHEREOF, the Pledgor has duly executed or caused this Agreement to be
duly executed as of [    ].

MARCONI INTELLECTUAL PROPERTY (RINGFENCE) INC.

By:      ____________________________________________
         Name:
         Title:

                                      C-23

<PAGE>

STATE OF                   )

                           ) ss.:

COUNTY OF                  )

On this ____ day of __________, ____, before me personally appeared ___________,
to me known, who, being by me duly sworn, did depose and say that he/she resides
at _________________________________________ and that he/she is _______________
of Pledgor; that he/she knows the seal of said corporation; that the seal
affixed to said instrument is such corporate seal; that it was affixed pursuant
to authority of the Board of Directors of said corporation and that he/she
signed his/her name thereto in his/her capacity as an authorized officer of said
corporation pursuant to such authority.

                                            ________________________________

                                                      Notary Public

                                      C-24

<PAGE>

                                                                 SCHEDULE 1-A TO
                                                SUPPLEMENT TO SECURITY AGREEMENT

                                  (COPYRIGHTS)

<TABLE>
<CAPTION>
COPYRIGHT                  REGISTRATION DATE           REGISTRATION NO.
---------                  -----------------           ----------------
<S>                        <C>                         <C>
</TABLE>

                                      C-25

<PAGE>

                                                                    EXHIBIT C TO
                                                              SECURITY AGREEMENT

                        SUPPLEMENT TO SECURITY AGREEMENT

                                    (PATENTS)

WHEREAS, MARCONI INTELLECTUAL PROPERTY (RINGFENCE) INC., a Delaware corporation
(herein referred to as "PLEDGOR"), having an address at c/o Marconi
Communications, Inc., 3000 Marconi Drive, Warrendale, PA 15086, owns the letters
patent, and/or applications for letters patent, of the United States of America,
more particularly described on Schedule 1-A annexed hereto as part hereof (the
"PATENTS");

WHEREAS, the Pledgor has entered into a Security Agreement dated as of May 19,
2003 (said Security Agreement, as it may hereafter be amended or otherwise
modified from time to time being the "SECURITY AGREEMENT", the terms defined
therein and not otherwise defined herein being used herein as therein defined)
in favor of the Secured Party; and

WHEREAS, pursuant to the Security Agreement, the Pledgor has granted to Secured
Party a security interest in all right, title and interest of Pledgor in and to
the Patents, together with all registrations and recordings thereof, including,
without limitation, applications, registrations and recordings in the United
States Patent and Trademark Office or in any similar office or agency of the
United States, any State thereof or any other country or any political
subdivision thereof, all whether now or hereafter owned or licensable by
Pledgor, and all reissues, continuations, continuations-in-part, term
restorations or extensions thereof, all Patent Licenses and all proceeds of all
of the foregoing, including, without limitation, any claims by Pledgor against
third parties for infringement thereof for the full term of the Patents (the
"COLLATERAL"), to secure the prompt payment and performance of the Secured
Obligations.

NOW, THEREFORE, for good and valuable consideration, receipt of which is hereby
acknowledged, the Pledgor does hereby further confirm, and put on the public
record, its grant to Secured Party of a security interest in and mortgage on the
Collateral to secure the prompt payment and performance of the Secured
Obligations.

The Pledgor does hereby further acknowledge and affirm that the rights and
remedies of Secured Party with respect to the assignment of and grant of a
security interest in the Collateral made hereby are more fully set forth in the
Security Agreement, the terms and provisions of which are hereby incorporated
herein by reference as if fully set forth herein.

Secured Party's address is 5th Floor, 100 Wood Street, London, EC2V 7EX,
United Kingdom.

                                      D-1

<PAGE>

IN WITNESS WHEREOF, the Pledgor has duly executed or caused this Supplement to
Security Agreement to be duly executed as of [ ].

MARCONI INTELLECTUAL PROPERTY (RINGFENCE) INC.

By:      ____________________________________________
         Name:
         Title:

                                      D-2

<PAGE>

STATE OF                   )

                           ) ss.:

COUNTY OF                  )

On this ____ day of ____________, before me personally appeared _______________,
to me known, who, being by me duly sworn, did depose and say that he/she resides
at _________________________________ and that he/she is _______________ of
Pledgor; that he/she knows the seal of said corporation; that the seal affixed
to said instrument is such corporate seal; that it was affixed pursuant to
authority of the Board of Directors of said corporation and that he/she signed
his/her name thereto in his/her capacity as an authorized officer of said
corporation pursuant to such authority.

                                            __________________________________

                                                       Notary Public

                                      D-3

<PAGE>

                                                                 SCHEDULE 1-A TO
                                                SUPPLEMENT TO SECURITY AGREEMENT

                                    (PATENTS)

<TABLE>
<CAPTION>
                           DATE FILED                  SERIAL NO.
TITLE                      OR GRANTED                  OR PATENT NO.
-----                      ----------                  --------------
<S>                        <C>                         <C>
</TABLE>

                                      D-4

<PAGE>

                                                                    EXHIBIT D TO
                                                              SECURITY AGREEMENT

                        SUPPLEMENT TO SECURITY AGREEMENT

                                  (TRADEMARKS)

WHEREAS, MARCONI INTELLECTUAL PROPERTY (RINGFENCE) INC., a Delaware corporation
(herein referred to as "PLEDGOR"), having an address at c/o Marconi
Communications, Inc., 3000 Marconi Drive, Warrendale, PA 15086, (1) has adopted,
used and is using, or (2) has intended to use and filed an application
indicating that intention, but has not yet filed an allegation of use under
Section l(c) or l(d) of the Trademark Act, or (3) has filed an application based
on an intention to use and has since used and has filed an allegation of use
under Section l(c) or l(d) of the Trademark Act, the trademarks, trade names,
trade styles and service marks listed on the annexed Schedule 1-A, which
trademarks, trade names, trade styles and service marks are registered in the
United States Patent and Trademark Office (the "TRADEMARKS"); and

WHEREAS, the Pledgor has entered into a Security Agreement dated as of May 19,
2003 (said Security Agreement, as it may hereafter be amended or otherwise
modified from time to time being the "SECURITY AGREEMENT", the terms defined
therein and not otherwise defined herein being used herein as therein defined)
in favor of the Secured Party; and

WHEREAS, pursuant to the Security Agreement, the Pledgor has granted to Secured
Party a security interest in all right, title and interest of the Pledgor in and
to the Trademarks, together with all prints and labels on which said Trademarks
have appeared or appear, designs and general intangibles of like nature, now
existing or hereafter adopted or acquired, and the goodwill of the business
symbolized by the Trademarks and the applications, registrations and recordings
in the United States Patent and Trademark Office or in any similar office or
agency of the United States of America, any State thereof, or any other country
or any political subdivision thereof, all whether now or hereafter owned or
licensable by Pledgor, and all reissues, extensions or renewals thereof, all
Trademark Licenses and all proceeds of all of the foregoing, including, without
limitation, any claims by Pledgor against third parties for infringement thereof
(the "COLLATERAL"), to secure the payment and performance of the Secured
Obligations.

NOW, THEREFORE, for good and valuable consideration, receipt of which is hereby
acknowledged, the Pledgor does hereby further confirm, and put on the public
record, its grant to Secured Party of a security interest in and mortgage on the
Collateral to secure the prompt payment and performance of the Secured
Obligations.

The Pledgor does hereby further acknowledge and affirm that the rights and
remedies of Secured Party with respect to the grant of, security interest in and
mortgage on the Collateral made hereby are more fully set forth in the Security
Agreement; the terms and provisions of which are hereby incorporated herein by
reference as if fully set forth herein.

Secured Party's address is 5th Floor, 100 Wood Street, London, EC2V 7EX,
United Kingdom.

                                      E-1

<PAGE>

IN WITNESS WHEREOF, the Pledgor has duly executed or caused this Supplement to
the Security Agreement to be duly executed as of [    ].

MARCONI INTELLECTUAL PROPERTY (RINGFENCE) INC.

By:      ___________________________________
         Name:
         Title:

                                      E-2

<PAGE>

STATE OF                   )

                           ) ss.:

COUNTY OF                  )

On this ____ day of _________, ____, before me personally appeared ____________,
to me known, who, being by me duly sworn, did depose and say that he/she resides
at _________________________________________ and that he/she is _______________
of Pledgor; that he/she knows the seal of said corporation; that the seal
affixed to said instrument is such corporate seal; that it was affixed pursuant
to authority of the Board of Directors of said corporation and that he/she
signed his/her name thereto in his/her capacity as an authorized officer of said
corporation pursuant to such authority.

                                             __________________________________

                                                       Notary Public

                                      E-3

<PAGE>

                                                                 SCHEDULE 1-A TO
                                                SUPPLEMENT TO SECURITY AGREEMENT

                                   TRADEMARKS

<TABLE>
<CAPTION>
                             APPLICATION OR            APPLICATION SERIAL NO. OR
TRADEMARK                  REGISTRATION DATE               REGISTRATION NO.
---------                  -----------------           -------------------------
<S>                        <C>                         <C>
</TABLE>

                                      E-4