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                                                                    EXHIBIT 10.6



                               SECURITY AGREEMENT

                                     among

                            PAGEMART WIRELESS, INC.,

                            CERTAIN SUBSIDIARIES OF
                            PAGEMART WIRELESS, INC.

                                      and


                             BANKERS TRUST COMPANY,
                              as Collateral Agent



                           Dated as of March 23, 1999






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                               SECURITY AGREEMENT


     SECURITY AGREEMENT, dated as of March 23, 1999, made by each of the
undersigned assignors (each an "Assignor" and, together with any other entity
that becomes an assignor hereunder pursuant to Section 10.12 hereof, the
"Assignors") in favor of Bankers Trust Company, as Collateral Agent (the
"Collateral Agent"), for the benefit of the Secured Creditors (as defined
below). Except as otherwise defined herein, capitalized terms used herein and
defined in the Credit Agreement (as defined below) shall be used herein as so
defined.

                             W I T N E S S E T H :


     WHEREAS, PageMart Wireless, Inc. (the "Borrower"), the lenders party from
time to time party thereto (the "Lenders"), Bankers Trust Company, as
Administrative Agent (together with any successor administrative agent, the
"Administrative Agent"), Morgan Stanley Senior Funding, Inc., as Syndication
Agent (the "Syndication Agent") and Bankers Trust Company and Morgan Stanley
Senior Funding, Inc., as Co-Arrangers have entered into a Credit Agreement,
dated as of March 23, 1999, providing for the making of Loans to, and the
issuance of Letters of Credit for the account of, the Borrower as contemplated
therein (as amended, modified or supplemented from time to time, the "Credit
Agreement") (the Lenders, the Administrative Agent, the Syndication Agent, the
Issuing Lender and the Collateral Agent are herein called the "Lender
Creditors");

     WHEREAS, the Borrower may at any time and from time to time enter into one
or more Interest Rate Protection Agreements or Other Hedging Agreements with
one or more Lenders or any affiliate thereof (each such Lender or affiliate,
even if the respective Lender subsequently ceases to be a Lender under the
Credit Agreement for any reason, together with such Lender's or affiliate's
successors and assigns, if any, collectively, the "Other Creditors," and
together with the Lender Creditors, are herein called the "Secured Creditors");

     WHEREAS, it is a condition precedent to the making of Loans to, and the
issuance of Letters of Credit for the account of, the Borrower under the Credit
Agreement that each Assignor shall have executed and delivered to the
Collateral Agent this Agreement; and

     WHEREAS, each Assignor will obtain benefits from the incurrence of Loans
by, and the issuance of Letters of Credit for the account of, the Borrower
under the Credit Agreement and the entering into by the Borrower of Interest
Rate Protection Agreements or Other Hedging Agreements and, accordingly, each
Assignor desires to enter into this Agreement in order to satisfy the condition
described in the preceding paragraph;

     NOW, THEREFORE, in consideration of the benefits accruing to each
Assignor, the receipt and sufficiency of which are hereby acknowledged, each
Assignor hereby makes the following representations and warranties to the
Collateral Agent for the benefit of the Secured

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Creditors and hereby covenants and agrees with the Collateral Agent for the
benefit of the Secured Creditors as follows:

                                   ARTICLE I

                               SECURITY INTERESTS

     1.1. Grant of Security Interests. (a) As security for the prompt and
complete payment and performance when due of all of its Obligations, each
Assignor does hereby assign and transfer unto the Collateral Agent, and does
hereby pledge and grant to the Collateral Agent for the benefit of the Secured
Creditors, a continuing security interest in, all of the right, title and
interest of such Assignor in, to and under all of the following, whether now
existing or hereafter from time to time acquired: (i) each and every
Receivable, (ii) all Contracts, together with all Contract Rights arising
thereunder, (iii) all Inventory, (iv) all Equipment, (v) all Marks, together
with the registrations and right to all renewals thereof, and the goodwill of
the business of such Assignor symbolized by the Marks, (vi) all Patents and
Copyrights, (vii) all computer programs of such Assignor and all intellectual
property rights therein and all other proprietary information of such Assignor,
including, but not limited to, Trade Secrets Rights, (viii) all other Goods,
General Intangibles, Investment Property, Permits, Chattel Paper, Documents,
Instruments and other assets (including cash) (subject, in the case of General
Intangibles and Permits constituting FCC Licenses only, to clause (xi) below),
(ix) the Cash Collateral Account and all monies, securities, instruments and
other investments deposited or required to be deposited in such Cash Collateral
Account, (x) all other bank, demand, time savings, cash management, passbook,
certificates of deposit and similar accounts maintained by such Assignor and
all monies, securities, instruments and other investments deposited or required
to be deposited in any of the foregoing accounts, (xi) all goodwill, going
concern value, and all of such Assignor's rights in, to or under, or relating
to, any license, permit or other authorization (each, an "FCC License") issued
by the FCC (provided, however, that such security interest does not include,
and the term "Collateral" does not include, at any time any FCC License to the
extent, but only to the extent, that such Assignor is prohibited at that time
from granting a security interest therein pursuant to the Communications Act,
and the FCC Rules, but includes, to the maximum extent permitted by law, all
rights incident or appurtenant to any such FCC License and the rights to
receive all proceeds, monies or other consideration derived or derivable from
or in connection with the sale, assignment or transfer of any FCC License); and
(xii) all Proceeds and products of any and all of the foregoing (all of the
above, collectively, the "Collateral").

     (b) The security interest of the Collateral Agent under this Agreement
extends to all Collateral of the kind which is the subject of this Agreement
which any Assignor may acquire at any time during the term of this Agreement.

     (c) Notwithstanding anything to the contrary contained in clauses (a) and
(b) above, it is acknowledged and agreed that the security interests created
hereby in any Equipment subject to the Vendor Financing Agreement shall be
second in priority to the security interest in such Equipment created pursuant
to the Vendor Financing Agreement for so long, and for only so long, as the
Vendor Financing Agreement remains in effect, and upon the termination of the


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Vendor Financing Agreement, such Equipment shall be subject to a first priority
security interest pursuant to this Agreement without any further action on the
part of any Assignor, the Collateral Agent or any Secured Creditor.

     (d) Notwithstanding anything to the contrary contained in clauses (a) and
(b) above or elsewhere in this Agreement, it is acknowledged and agreed that
(i) the security interest created hereby shall not extend to any computer
program or patents owned by a third Person in which any Assignor has rights of
usage thereof to the extent (and only to the extent) the granting of a security
interest therein is expressly prohibited by an agreement relating thereto to
which such Assignor is a party and (ii) the security interest created hereunder
in, and the Collateral Agent's and the Secured Creditors' rights and remedies
hereunder with respect to, any Patents that any Assignor has granted rights
therein to a third Person shall be subject to the respective agreement relating
to such grant for so long as, and for only so long as, such agreement remains
in effect; provided, however, that (A) such computer programs or patents, as
the case may be, described in preceding clause (i) above shall be excluded from
the Collateral only to the extent and only for so long as the relevant
agreement continues validly to prohibit the creation of such security interest,
and upon the expiration of such prohibition, all computer programs or patents,
as the case may be, as to which such prohibition previously applied shall
automatically be included in the Collateral, without any further action on the
part of any Assignor, the Collateral Agent, or any other Secured Creditor and
(B) any residual rights of the respective Assignor or Assignors with respect to
Patents described in preceding clause (ii) above shall be included in the
Collateral (and not be subject to the interest of any third Persons to the
fullest extent permitted under the relevant agreement described in clause (ii)
above).

     (e) It is acknowledged and agreed that the security interest created
hereby does not extend to any assets owned by any third Person (and not owned
by any Assignor) that are located at any Real Property sites of any Assignor.

     1.2. Power of Attorney. Each Assignor hereby constitutes and appoints the
Collateral Agent its true and lawful attorney, irrevocably, with full power
after the occurrence of and during the continuance of an Event of Default (in
the name of such Assignor or otherwise) to act, require, demand, receive,
compound and give acquittance for any and all moneys and claims for moneys due
or to become due to such Assignor under or arising out of the Collateral, to
endorse any checks or other instruments or orders in connection therewith and,
subject, in the case of any exercise by the Pledgee of any rights or remedies
that effects an assignment or transfer of control of any FCC License, to
receipt of any approvals that may be required under the Communications Act or
the FCC Rules, to file any claims or take any action or institute any
proceedings which the Collateral Agent may deem to be necessary or advisable to
protect the interests of the Secured Creditors, which appointment as attorney
is coupled with an interest.


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                                   ARTICLE II

               GENERAL REPRESENTATIONS, WARRANTIES AND COVENANTS

     Each Assignor represents, warrants and covenants, which representations,
warranties and covenants shall survive execution and delivery of this
Agreement, as follows:

     2.1. Necessary Filings. All filings, registrations and recordings
necessary or appropriate to create, preserve and perfect the security interest
granted by such Assignor to the Collateral Agent hereby in respect of the
Collateral have been accomplished (or, in the case of (i) any Collateral which
has been moved as described in the last sentence in Section 2.5 of this
Agreement, will have been accomplished within the time period provided in such
sentence or (ii) all other Collateral, will have been accomplished on the
Business Day immediately following the Effective Date) and the security
interest granted to the Collateral Agent pursuant to this Agreement in and to
the Collateral creates a perfected security interest therein prior to the
rights of all other Persons therein and subject to no other Liens (other than
Permitted Liens) and is entitled to all the rights, priorities and benefits
afforded by the Uniform Commercial Code or other relevant law as enacted in any
relevant jurisdiction to perfected security interests, in each case to the
extent that the Collateral consists of the type of property in which a security
interest may be perfected by filing a financing statement under the Uniform
Commercial Code as enacted in any relevant jurisdiction or in the United States
Patent and Trademark Office or in the United States Copyright Office.

     2.2. No Liens. Such Assignor is, and as to Collateral acquired by it from
time to time after the date hereof such Assignor will be, the owner of all
Collateral free from any Lien, security interest, encumbrance or other right,
title or interest of any Person (other than Permitted Liens), and such Assignor
shall defend the Collateral against all claims and demands of all Persons at
any time claiming the same or any interest therein adverse to the Collateral
Agent.

     2.3. Other Financing Statements. As of the date hereof, there is no
financing statement (or similar statement or instrument of registration under
the law of any jurisdiction) covering or purporting to cover any interest of
any kind in the Collateral (other than financing statements filed in respect of
Permitted Liens), and so long as the Termination Date has not occurred, such
Assignor will not execute or authorize to be filed in any public office any
financing statement (or similar statement or instrument of registration under
the law of any jurisdiction) or statements relating to the Collateral, except
financing statements filed or to be filed in respect of and covering the
security interests granted hereby by such Assignor or in connection with
Permitted Liens.

     2.4. Chief Executive Office, Record Locations. The chief executive office
of such Assignor is located at the address indicated on Annex A hereto for such
Assignor. Such Assignor will not move its chief executive office except to such
new location as such Assignor may establish in accordance with the last
sentence of this Section 2.4. The originals of all documents evidencing all
Receivables and Contract Rights of such Assignor and the only original books of
account and records of such Assignor relating thereto are, and will continue to
be, kept at such chief executive office, at one or more of the other locations
set forth on Annex A hereto or at 


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such new locations as such Assignor may establish in accordance with the last
sentence of this Section 2.4. All Receivables and Contract Rights of such
Assignor are, and will continue to be, maintained at, and controlled and
directed (including, without limitation, for general accounting purposes) from,
the office locations described above or such new location established in
accordance with the last sentence of this Section 2.4. No Assignor shall
establish new locations for such offices until (i) it shall have given to the
Collateral Agent not less than 15 days' prior written notice of its intention
to do so, clearly describing such new location and providing such other
information in connection therewith as the Collateral Agent may reasonably
request, (ii) with respect to such new location, it shall have taken all action
reasonably satisfactory to the Collateral Agent to maintain the security
interest of the Collateral Agent in the Collateral intended to be granted
hereby at all times fully perfected and in full force and effect and (iii) at
the request of the Collateral Agent, it shall have furnished an opinion of
counsel reasonably acceptable to the Collateral Agent to the effect that all
financing or continuation statements and amendments or supplements thereto have
been filed in the appropriate filing office or offices, and all other actions
have been taken, in order to perfect (and maintain the perfection of) the
security interest granted hereby in respect of the types of Collateral referred
to in Section 1.1 hereof.

     2.5. Location of Inventory and Equipment. All Inventory and Equipment
(other than Equipment consisting of transmitter sites owned by each Assignor)
held on the date hereof by each Assignor is located at one of the locations
shown on Part A of Annex B hereto for such Assignor. All Equipment constituting
transmitter sites held on the date hereof by each Assignor is located in one of
the States of the United States of America shown on Part B of Annex B hereto
for such Assignor. Each Assignor agrees that all Inventory and Equipment now
held or subsequently acquired by it shall be kept at (or shall be in transport
to) any one of the locations shown on the respective part of Annex B hereto
(or, in the case of Equipment constituting transmitter sites only, any other
location in which the Collateral Agent has filed UCC-1 financing statements in
order to ensure that the Collateral Agent's lien on such Equipment remains
perfected), or such new location as such Assignor may establish in accordance
with the last sentence of this Section 2.5. Except with respect to Equipment
consisting of transmitter sites as otherwise provided above, any Assignor may
establish a new location for Inventory and Equipment only if (i) it shall have
given to the Collateral Agent not less than 15 days' prior written notice of
its intention so to do, clearly describing such new location and providing such
other information in connection therewith as the Collateral Agent may request,
(ii) with respect to such new location, it shall have taken all action
reasonably satisfactory to the Collateral Agent to maintain the security
interest of the Collateral Agent in the Collateral intended to be granted
hereby at all times fully perfected and in full force and effect and (iii) at
the request of the Collateral Agent, it shall have furnished an opinion of
counsel reasonably acceptable to the Collateral Agent to the effect that all
financing or continuation statements and amendments or supplements thereto have
been filed in the appropriate filing office or offices, and all other actions
have been taken, in order to perfect (and maintain the perfection of) the
security interest granted hereby in respect of the types of Collateral referred
to in Section 1.1 hereof. Notwithstanding anything to the contrary contained in
this Section 2.5, in the event any Assignor has moved any Equipment
constituting transmitter sites to a new location such that the security
interest created hereunder in such transmitter sites is no longer perfected,
within 60 days following such move, such Assignor shall provide the Collateral
Agent with the new location or locations of such 


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transmitter sites and, upon the request of the Collateral Agent, shall enter
into UCC-1 financing statements, and shall take any other actions as may be
reasonably requested by the Collateral Agent, to ensure that the Collateral
Agent's lien on such transmitter sites remains perfected.

     2.6. Recourse. This Agreement is made with full recourse to each Assignor
(including, without limitation, with full recourse to all assets of such
Assignor) and pursuant to and upon all the warranties, representations,
covenants and agreements on the part of such Assignor contained herein, in the
other Secured Debt Agreements and otherwise in writing in connection herewith
or therewith.

     2.7. Trade Names; Change of Name. No Assignor has or operates in any
jurisdiction under, or in the preceding five years has had or has operated in
any jurisdiction under, any trade names, fictitious names or other names except
its legal name and such other trade or fictitious names as are listed on Annex
C hereto for such Assignor. No Assignor shall change its legal name or assume
or operate in any jurisdiction under any trade, fictitious or other name except
those names listed on Annex C hereto for such Assignor and new names
established in accordance with the last sentence of this Section 2.7. No
Assignor shall assume or operate in any jurisdiction under any new trade,
fictitious or other name until (i) it shall have given to the Collateral Agent
not less than 15 days' prior written notice of its intention so to do, clearly
describing such new name and the jurisdictions in which such new name shall be
used and providing such other information in connection therewith as the
Collateral Agent may reasonably request, (ii) with respect to such new name, it
shall have taken all action reasonably requested by the Collateral Agent to
maintain the security interest of the Collateral Agent in the Collateral
intended to be granted hereby at all times fully perfected and in full force
and effect and (iii) at the request of the Collateral Agent, it shall have
furnished an opinion of counsel reasonably acceptable to the Collateral Agent
to the effect that all financing or continuation statements and amendments or
supplements thereto have been filed in the appropriate filing office or
offices, and all other actions have been taken, in order to perfect (and
maintain the perfection of) the security interest granted hereby in respect of
the types of Collateral referred to in Section 1.1 hereof.

                                  ARTICLE III

                   SPECIAL PROVISIONS CONCERNING RECEIVABLES;
                  CONTRACT RIGHTS; INSTRUMENTS; CHATTEL PAPER

     3.1. Additional Representations and Warranties. As of the time when each
of its Receivables arises, each Assignor shall be deemed to have represented
and warranted that such Receivable, and all records, papers and documents
relating thereto (if any) are what they purport to be, and such Receivable will
evidence true and valid obligations of the account debtor named therein.

     3.2. Maintenance of Records. Each Assignor will keep and maintain at its
own cost and expense accurate records of its Receivables and Contracts,
including, but not limited to, originals of all documentation (including each
Contract) with respect thereto, records of all payments received, all credits
granted thereon, all merchandise returned and all other dealings therewith, and
such Assignor will make the same available on such Assignor's premises to the



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Collateral Agent for inspection, at such Assignor's own cost and expense, at
any and all reasonable times upon prior notice to such Assignor. Upon the
occurrence and during the continuance of an Event of Default and at the request
of the Collateral Agent, such Assignor shall, at its own cost and expense,
deliver all tangible evidence of its Receivables and Contract Rights
(including, without limitation, all documents evidencing the Receivables and
all Contracts) and such books and records to the Collateral Agent or to its
representatives (copies of which evidence and books and records may be retained
by such Assignor). Upon the occurrence and during the continuance of an Event
of Default and if the Collateral Agent so directs, such Assignor shall legend,
in form and manner satisfactory to the Collateral Agent, the Receivables and
the Contracts, as well as books, records and documents (if any) of such
Assignor evidencing or pertaining to such Receivables and Contracts with an
appropriate reference to the fact that such Receivables and Contracts have been
assigned to the Collateral Agent and that the Collateral Agent has a security
interest therein.

     3.3. Direction to Account Debtors; Contracting Parties; etc. Upon the
occurrence and during the continuance of an Event of Default, and if the
Collateral Agent so directs any Assignor, such Assignor agrees (x) to cause all
payments on account of the Receivables and Contracts to be made directly to the
Cash Collateral Account, (y) that the Collateral Agent may, at its option,
directly notify the obligors with respect to any Receivables and/or under any
Contracts to make payments with respect thereto as provided in the preceding
clause (x), and (z) that the Collateral Agent may enforce collection of any
such Receivables and Contracts and may adjust, settle or compromise the amount
of payment thereof, in the same manner and to the same extent as such Assignor.
Without notice to or assent by any Assignor, the Collateral Agent may apply any
or all amounts then in, or thereafter deposited in, the Cash Collateral Account
which application shall be effected in the manner provided in Section 7.4 of
this Agreement; provided however, that at such time as no Default or Event of
Default shall be continuing, all funds in the Cash Collateral Account shall be
disbursed to the respective Assignor. The costs and expenses (including
reasonable attorneys' fees) of collection, whether incurred by an Assignor or
the Collateral Agent, shall be borne by the relevant Assignor. The Collateral
Agent shall deliver a copy of each notice referred to in the preceding clause
(y) to the relevant Assignor, provided that the failure by the Collateral Agent
to so notify such Assignor shall not affect the effectiveness of such notice or
the other rights of the Collateral Agent created by this Section 3.3.

     3.4. Modification of Terms; etc. Except in accordance with such Assignor's
ordinary course of business and consistent with reasonable business judgment,
no Assignor shall rescind or cancel any indebtedness evidenced by any
Receivable or under any Contract, or modify any term thereof or make any
adjustment with respect thereto, or extend or renew the same, or compromise or
settle any material dispute, claim, suit or legal proceeding relating thereto,
or sell any Receivable or Contract, or interest therein, without the prior
written consent of the Collateral Agent. Each Assignor will duly fulfill all
obligations on its part to be fulfilled under or in connection with the
Receivables and Contracts and will do nothing to impair the rights of the
Collateral Agent in the Receivables or Contracts.

     3.5. Collection. Each Assignor shall endeavor in accordance with
reasonable business practices to cause to be collected from the account debtor
named in each of its Receivables or obligor under any Contract, as and when due
(including, without limitation, 


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amounts which are delinquent, such amounts to be collected in accordance with
generally accepted lawful collection procedures) any and all amounts owing
under or on account of such Receivable or Contract, and apply forthwith upon
receipt thereof all such amounts as are so collected to the outstanding balance
of such Receivable or under such Contract, except that, prior to the occurrence
of an Event of Default, any Assignor may allow in the ordinary course of
business as adjustments to amounts owing under its Receivables and Contracts
(i) an extension or renewal of the time or times of payment, or settlement for
less than the total unpaid balance, which such Assignor finds appropriate in
accordance with reasonable business judgment and (ii) a refund or credit due as
a result of returned or damaged merchandise or improperly performed services or
for other reasons which such Assignor finds appropriate in accordance with
reasonable business judgment. The reasonable costs and expenses (including,
without limitation, reasonable attorneys' fees) of collection, whether incurred
by an Assignor or the Collateral Agent, shall be borne by the relevant
Assignor.

     3.6. Instruments. If any Assignor owns or acquires any Instrument
constituting Collateral, such Assignor will within 10 Business Days notify the
Collateral Agent thereof, and upon request by the Collateral Agent will
promptly deliver such Instrument to the Collateral Agent appropriately endorsed
to the order of the Collateral Agent as further security hereunder.

     3.7. Assignors Remain Liable Under Receivables. Anything herein to the
contrary notwithstanding, the Assignors shall remain liable under each of the
Receivables to observe and perform all of the conditions and obligations to be
observed and performed by it thereunder, all in accordance with the terms of
any agreement giving rise to such Receivables and applicable law. Neither the
Collateral Agent nor any other Secured Creditor shall have any obligation or
liability under any Receivable (or any agreement giving rise thereto) by reason
of or arising out of this Agreement or the receipt by the Collateral Agent or
any other Secured Creditor of any payment relating to such Receivable pursuant
hereto, nor shall the Collateral Agent or any other Secured Creditor be
obligated in any manner to perform any of the obligations of any Assignor under
or pursuant to any Receivable (or any agreement giving rise thereto), to make
any payment, to make any inquiry as to the nature or the sufficiency of any
payment received by them or as to the sufficiency of any performance by any
party under any Receivable (or any agreement giving rise thereto), to present
or file any claim, to take any action to enforce any performance or to collect
the payment of any amounts which may have been assigned to them or to which
they may be entitled at any time or times.

     3.8. Assignors Remain Liable Under Contracts. Anything herein to the
contrary notwithstanding, the Assignors shall remain liable under each of the
Contracts to observe and perform all of the conditions and obligations to be
observed and performed by them thereunder, all in accordance with and pursuant
to the terms and provisions of each Contract and applicable law. Neither the
Collateral Agent nor any other Secured Creditor shall have any obligation or
liability under any Contract by reason of or arising out of this Agreement or
the receipt by the Collateral Agent or any other Secured Creditor of any
payment relating to such contract pursuant hereto, nor shall the Collateral
Agent or any other Secured Creditor be obligated in any manner to perform any
of the obligations of any Assignor under or pursuant to any Contract, to make
any payment, to make any inquiry as to the nature or the sufficiency of any
performance by any party under any Contract, to present or file any claim, to
take any action to enforce any performance or 


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to collect the payment of any amounts which may have been assigned to them or
to which they may be entitled at any time or times.

     3.9. Further Actions. (a) Each Assignor will, at its own expense, make,
execute, endorse, acknowledge, file and/or deliver to the Collateral Agent from
time to time such vouchers, invoices, schedules, confirmatory assignments,
conveyances, financing statements, transfer endorsements, certificates, reports
and other assurances or instruments and take such further steps relating to its
Receivables, Contracts, Instruments and other property or rights covered by the
security interest hereby granted, as the Collateral Agent may reasonably
require.

     (b) Each Assignor agrees that in the event of any change in any
requirement of law occurring after the date hereof that affects in any manner
the Collateral Agent's rights of access to, or use or sale of the FCC Licenses
or the procedures necessary to enable the Collateral Agent to obtain such
rights of access, use or sale (including, without limitation, changes allowing
greater such access), each Assignor upon request of the Collateral Agent or the
Required Lenders, shall enter into an amendment to this Agreement in form and
substance satisfactory to the Collateral Agent to provide the Collateral Agent
with such rights to the greatest extent possible consistent with then
applicable requirements of law, including without limitation the Communications
Act and the FCC Rules.

                                   ARTICLE IV

                    SPECIAL PROVISIONS CONCERNING TRADEMARKS

     4.1. Additional Representations and Warranties. Each Assignor represents
and warrants that it is the true and lawful owner of or otherwise has the right
to use the registered Marks listed in Annex D hereto for such Assignor and that
said listed Marks include all United States marks and applications for United
States marks registered in the United States Patent and Trademark Office that
such Assignor owns or uses in connection with its business as of the date
hereof. Each Assignor represents and warrants that it owns, is licensed to use
or otherwise has the right to use, all Marks that it uses, except to the extent
that any such lack of ownership, license or right could not reasonably be
expected to have a material adverse effect on the business, operations,
property, assets, liabilities, condition (financial or otherwise) or prospects
of the Borrower or of the Borrower and its Subsidiaries taken as a whole. Each
Assignor further warrants that it has no knowledge of any third party claim
that any aspect of such Assignor's present or contemplated business operations
materially infringes or will materially infringe any trademark, service mark or
trade name. Each Assignor represents and warrants that it is the true and
lawful owner of or otherwise has the right to use all U.S. trademark
registrations and applications listed in Annex D hereto and that said
registrations are valid, subsisting, have not been cancelled and that such
Assignor is not aware of any third-party claim that any of said registrations
is invalid or unenforceable, or is not aware that there is any reason that any
of said registrations is invalid or unenforceable, or is not aware that there
is any reason that any of said applications will not pass to registration. Upon
the occurrence and continuance of an Event of Default, each Assignor hereby
grants to the Collateral Agent an absolute power of attorney to sign any
document which may be required by the United States Patent and Trademark Office
in 


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order to effect an absolute assignment of all right, title and interest in each
Mark, and record the same.

     4.2. Licenses and Assignments. Except as otherwise permitted by the
Secured Debt Agreements, each Assignor hereby agrees not to divest itself of
any right under any Mark absent prior written approval of the Collateral Agent.

     4.3. Infringements. Each Assignor agrees, promptly upon learning thereof,
to notify the Collateral Agent in writing of the name and address of, and to
furnish such pertinent information that may be available with respect to, any
party who such Assignor believes is materially infringing or diluting or
otherwise violating in any material respect any of such Assignor's rights in
and to any Mark, or with respect to any party claiming that such Assignor's use
of any Mark violates in any material respect any property right of that party.
Each Assignor further agrees, unless otherwise agreed by the Collateral Agent,
to prosecute any Person materially infringing any Mark in accordance with
reasonable business practices.

     4.4. Preservation of Marks. Each Assignor agrees to use its Significant
Marks in interstate commerce during the time in which this Agreement is in
effect and to take all such other actions as are necessary to preserve such
Significant Marks as trademarks or service marks under the laws of the United
States.

     4.5. Maintenance of Registration. Each Assignor shall, at its own expense,
diligently process all documents required to maintain trademark registrations
material to its business, financial condition or property, including, but not
limited to, affidavits of use and applications for renewals of registration in
the United States Patent and Trademark Office for all of its registered
Significant Marks, and shall pay all fees and disbursements in connection
therewith and shall not abandon any such filing of affidavit of use or any such
application of renewal prior to the exhaustion of all administrative and
judicial remedies without prior written consent of the Collateral Agent.

     4.6. Future Registered Marks. If any Mark registration is issued hereafter
to any Assignor as a result of any application now or hereafter pending before
the United States Patent and Trademark Office, within 30 days of receipt of
such certificate, such Assignor shall deliver to the Collateral Agent a copy of
such certificate, and an assignment for security in such Mark, to the
Collateral Agent and at the expense of such Assignor, confirming the assignment
for security in such Mark to the Collateral Agent hereunder, the form of such
security to be substantially the same as the form hereof or in such other form
as may be reasonably satisfactory to the Collateral Agent.

     4.7. Remedies. If an Event of Default shall occur and be continuing, the
Collateral Agent may, by written notice to the relevant Assignor, take any or
all of the following actions: (i) declare the entire right, title and interest
of such Assignor in and to each of the Marks, together with all trademark
rights and rights of protection to the same, vested in the Collateral Agent for
the benefit of the Secured Creditors, in which event such rights, title and
interest shall immediately vest, in the Collateral Agent for the benefit of the
Secured Creditors, and the Collateral Agent shall be entitled to exercise the
power of attorney referred to in Section 4.1 


                                     -10-
<PAGE>   12

hereof to execute, cause to be acknowledged and notarized and record said
absolute assignment with the applicable agency; (ii) take and use or sell the
Marks and the goodwill of such Assignor's business symbolized by the Marks and
the right to carry on the business and use the assets of such Assignor in
connection with which the Marks have been used; and (iii) direct such Assignor
to refrain, in which event such Assignor shall refrain, from using the Marks in
any manner whatsoever, directly or indirectly, and such Assignor shall execute
such further documents that the Collateral Agent may reasonably request to
further confirm this and to transfer ownership of the Marks and registrations
and any pending trademark application in the United States Patent and Trademark
Office to the Collateral Agent.

                                   ARTICLE V

                         SPECIAL PROVISIONS CONCERNING
                     PATENTS, COPYRIGHTS AND TRADE SECRETS

     5.1. Additional Representations and Warranties. Each Assignor represents
and warrants that it is the true and lawful owner of all rights in (i) all
United States trade secrets and proprietary information necessary to operate
the business of the Assignor (the "Trade Secret Rights"), (ii) the Patents
listed in Annex E hereto for such Assignor and that said Patents include all
the United States patents and applications for United States patents that such
Assignor owns as of the date hereof and (iii) the Copyrights listed in Annex F
hereto for such Assignor and that said Copyrights constitute all the United
States copyrights registered with the United States Copyright Office and
applications to United States copyrights that such Assignor owns as of the date
hereof. Each Assignor further warrants that it has no knowledge of any third
party claim that any aspect of such Assignor's present or contemplated business
operations materially infringes or will materially infringe any patent or such
Assignor has misappropriated any trade secret or proprietary information. Upon
the occurrence and continuance of an Event of Default, each Assignor hereby
grants to the Collateral Agent an absolute power of attorney to sign any
document which may be required by the United States Patent and Trademark Office
in order to effect an absolute assignment of all right, title and interest in
each Patent, and to record the same.

     5.2. Licenses and Assignments. Except as otherwise permitted by the
Secured Debt Agreements, each Assignor hereby agrees not to divest itself of
any right under any Significant Patent or Significant Copyright absent prior
written approval of the Collateral Agent.

     5.3. Infringements. Each Assignor agrees, promptly upon learning thereof,
to furnish the Collateral Agent in writing with all pertinent information
available to such Assignor with respect to any material infringement,
contributing material infringement or active inducement to materially infringe
in any Patent or Copyright or to any claim that the practice of any Patent or
use of any Copyright violates any property right of a third party, or with
respect to any misappropriation of any Trade Secret Right or any claim that
practice of any Trade Secret Right violates any property right of a third
party. Each Assignor further agrees, absent direction of the Collateral Agent
to the contrary, diligently to prosecute any Person materially infringing any
Patent or Copyright or any Person materially misappropriating any Trade Secret
Right in accordance with such Assignor's reasonable business judgment.


                                     -11-
<PAGE>   13

     5.4. Maintenance of Patents or Copyright. At its own expense, each
Assignor shall make timely payment of all post-issuance fees required pursuant
to 35 U.S.C. ss. 41 to maintain in force its rights under each Significant
Patent or Significant Copyright, absent prior written consent of the Collateral
Agent.

     5.5. Prosecution of Patent and Copyright Applications. At its own expense,
each Assignor shall diligently prosecute all applications for (i) United States
Patents listed in Annex E hereto and (ii) Copyrights listed on Annex F hereto,
in each case for such Assignor and shall, consistent with reasonable business
judgment, not abandon any such application prior to exhaustion of all
administrative and judicial remedies, absent written consent of the Collateral
Agent, unless such Assignor shall determine that the prosecution thereof is no
longer desirable in the conduct of the business of such Assignor in that the
cessation of such prosecution is not disadvantageous in any material respect to
such Assignor.

     5.6. Other Patents and Copyrights. Within 30 days of the acquisition or
issuance of a United States Patent, registration of a Copyright, or acquisition
of a registered Copyright, or of filing of an application for a United States
Patent or Copyright, the relevant Assignor shall deliver to the Collateral
Agent a copy of said Copyright or certificate or registration of, or
application therefor, said Patents, as the case may be, with an assignment for
security as to such Patent or Copyright, as the case may be, to the Collateral
Agent and at the expense of such Assignor, confirming the assignment for
security, the form of such assignment for security to be substantially the same
as the form hereof or in such other form as may be reasonably satisfactory to
the Collateral Agent.

     5.7. Remedies. If an Event of Default shall occur and be continuing, the
Collateral Agent may by written notice to the relevant Assignor, take any or
all of the following actions: (i) declare the entire right, title, and interest
of such Assignor in each of the Patents and Copyrights vested in the Collateral
Agent for the benefit of the Secured Creditors, in which event such right,
title, and interest shall immediately vest in the Collateral Agent for the
benefit of the Secured Creditors, in which case the Collateral Agent shall be
entitled to exercise the power of attorney referred to in Section 5.1 hereof to
execute, cause to be acknowledged and notarized and to record said absolute
assignment with the applicable agency; (ii) take and practice or sell the
Patents and Copyrights; and (iii) direct such Assignor to refrain, in which
event such Assignor shall refrain, from practicing the Patents and using the
Copyrights directly or indirectly, and such Assignor shall execute such further
documents as the Collateral Agent may reasonably request further to confirm
this and to transfer ownership of the Patents and Copyrights to the Collateral
Agent for the benefit of the Secured Creditors.

                                   ARTICLE VI

                      PROVISIONS CONCERNING ALL COLLATERAL

     6.1. Protection of Collateral Agent's Security. Each Assignor will do
nothing to impair the rights of the Collateral Agent in the Collateral. Each
Assignor will at all times keep its Inventory and Equipment insured in favor of
the Collateral Agent, at such Assignor's own 


                                     -12-
<PAGE>   14

expense to the extent and in the manner provided in the Credit Agreement.
Except to the extent otherwise permitted to be retained by such Assignor or
applied by such Assignor pursuant to the terms of the Credit Agreement, the
Collateral Agent shall, at the time any proceeds of such insurance are
distributed to the Secured Creditors, apply such proceeds in accordance with
Section 7.4 hereof. Each Assignor assumes all liability and responsibility in
connection with the Collateral acquired by it and the liability of such
Assignor to pay the Obligations shall in no way be affected or diminished by
reason of the fact that such Collateral may be lost, destroyed, stolen, damaged
or for any reason whatsoever unavailable to such Assignor.

     6.2. Warehouse Receipts Non-negotiable. Each Assignor agrees that if any
warehouse receipt or receipt in the nature of a warehouse receipt is issued
with respect to any of its Inventory, such Assignor shall request that such
warehouse receipt or receipt in the nature thereof shall not be "negotiable"
(as such term is used in Section 7-104 of the UCC as in effect in any relevant
jurisdiction or under other relevant law).

     6.3. Further Actions. Each Assignor will, at its own expense and upon the
request of the Collateral Agent, make, execute, endorse, acknowledge, file
and/or deliver to the Collateral Agent from time to time such lists,
descriptions and designations of its Collateral, warehouse receipts, receipts
in the nature of warehouse receipts, bills of lading, documents of title,
vouchers, invoices, schedules, confirmatory assignments, conveyances, financing
statements, transfer endorsements, certificates, reports and other assurances
or instruments and take such further steps relating to the Collateral and other
property or rights covered by the security interest hereby granted, which the
Collateral Agent deems reasonably appropriate or advisable to perfect, preserve
or protect its security interest in the Collateral.

     6.4. Financing Statements. Each Assignor agrees to execute and deliver to
the Collateral Agent such financing statements, in form reasonably acceptable
to the Collateral Agent, as the Collateral Agent may from time to time
reasonably request or as are necessary or desirable in the opinion of the
Collateral Agent to establish and maintain a valid, enforceable, first priority
perfected security interest in the Collateral as provided herein and the other
rights and security contemplated hereby all in accordance with the UCC as
enacted in any and all relevant jurisdictions or any other relevant law. Each
Assignor will pay any applicable filing fees, recordation taxes and related
expenses relating to its Collateral. Each Assignor hereby authorizes the
Collateral Agent to file any such financing statements without the signature of
such Assignor where permitted by law.

     6.5. FCC Licenses. Each Assignor agrees to take any and all necessary and
appropriate commercially reasonable actions to preserve the FCC Licenses and to
otherwise prevent any adverse modification, revocation, suspension,
cancellation, or refusal by the FCC to renew any of the FCC Licenses except to
the extent such modification, revocation, suspension, cancellation or refusal
could not reasonably be expected to have a material adverse effect on the
business, operations, property, assets, liabilities, condition (financial or
otherwise) or prospects of the Borrower or of the Borrower and its Subsidiaries
taken a whole. To that end, each Assignor shall execute any and all documents
required by the FCC or any other governmental authority or requested by the
Borrower or the Collateral Agent, and to provide any information with its
possession reasonably requested by any of the foregoing, to ensure that any and
all applications,


                                     -13-
<PAGE>   15

reports, and other filings are made with the FCC or any other governmental
authority in a timely fashion and that no action is taken by the FCC, any
court, or any governmental authority which could have a material adverse effect
on any of the FCC Licenses.

                                  ARTICLE VII

                  REMEDIES UPON OCCURRENCE OF EVENT OF DEFAULT

     7.1. Remedies; Obtaining the Collateral Upon Default. Each Assignor agrees
that, if any Event of Default shall have occurred and be continuing, then and
in every such case, the Collateral Agent, in addition to any rights now or
hereafter existing under applicable law, shall have all rights as a secured
creditor under any UCC, and such additional rights and remedies to which a
secured creditor is entitled under the laws in effect, in all relevant
jurisdictions and may:

     (i) personally, or by agents or attorneys, immediately take possession of
the Collateral or any part thereof, from such Assignor or any other Person who
then has possession of any part thereof with or without notice or process of
law, and for that purpose may enter upon such Assignor's premises where any of
the Collateral is located and remove the same and use in connection with such
removal any and all services, supplies, aids and other facilities of such
Assignor;

     (ii) instruct the obligor or obligors on any agreement, instrument or
other obligation (including, without limitation, the Receivables and the
Contracts) constituting the Collateral to make any payment required by the
terms of such agreement, instrument or other obligation directly to the
Collateral Agent and may exercise any and all remedies of such Assignor in
respect of such Collateral;

     (iii) withdraw all monies, securities and instruments in the Cash
Collateral Account for application to the Obligations in accordance with
Section 7.4 hereof;

     (iv) sell, assign or otherwise liquidate any or all of the Collateral or
any part thereof in accordance with Section 7.2 hereof, or direct the relevant
Assignor to sell, assign or otherwise liquidate any or all of the Collateral or
any part thereof, and, in each case, take possession of the proceeds of any
such sale or liquidation;

     (v) take possession of the Collateral or any part thereof, by directing
the relevant Assignor in writing to deliver the same to the Collateral Agent at
any place or places designated by the Collateral Agent, in which event such
Assignor shall at its own expense:

         (x) forthwith cause the same to be moved to the place or places so 
     designated by the Collateral Agent and there delivered to the Collateral
     Agent;

         (y) store and keep any Collateral so delivered to the Collateral Agent
     at such place or places pending further action by the Collateral Agent as
     provided in Section 7.2 hereof; and


                                     -14-
<PAGE>   16

         (z) while the Collateral shall be so stored and kept, provide such 
     guards and maintenance services as shall be necessary to protect the same
     and to preserve and maintain the same in good condition; and

     (vi) license or sublicense, whether on an exclusive or nonexclusive basis,
any Marks, Patents or Copyrights included in the Collateral for such term and
on such conditions and in such manner as the Collateral Agent shall in its sole
judgment determine;

it being understood that each Assignor's obligation to so deliver the
Collateral is of the essence of this Agreement and that, accordingly, upon
application to a court of equity having jurisdiction, the Collateral Agent
shall be entitled to a decree requiring specific performance by such Assignor
of said obligation. By accepting the benefits of this Agreement, the Secured
Creditors agree that this Agreement may be enforced only by the action of the
Collateral Agent acting upon the instructions of the Required Secured Creditors
and that no other Secured Creditor shall have any right individually to seek to
enforce this Agreement or to realize upon the security to be granted hereby, it
being understood and agreed that such rights and remedies may be exercised by
the Collateral Agent for the benefit of the Secured Creditors upon the terms of
this Agreement and the Credit Agreement.

     7.2. Remedies; Disposition of the Collateral. If any Event of Default
shall have occurred and be continuing, then any Collateral repossessed by the
Collateral Agent under or pursuant to Section 7.1 hereof and any other
Collateral whether or not so repossessed by the Collateral Agent, may be sold,
assigned, leased or otherwise disposed of under one or more contracts or as an
entirety, and without the necessity of gathering at the place of sale the
property to be sold, and in general in such manner, at such time or times, at
such place or places and on such terms as the Collateral Agent may, in
compliance with any mandatory requirements of applicable law (including, in the
case of any disposition of the FCC Licenses or transfer of control thereof, the
Communication Act and the FCC Rules), determine to be commercially reasonable.
Subject to, in the case of any disposition of the FCC Licenses or transfer of
control thereof, receipt of any approvals required under the Communications Act
or the FCC Rules, any of the Collateral may be sold, leased or otherwise
disposed of, in the condition in which the same existed when taken by the
Collateral Agent or after any overhaul or repair at the expense of the relevant
Assignor which the Collateral Agent shall determine to be commercially
reasonable. Any such disposition which shall be a private sale or other private
proceedings permitted by such requirements shall be made upon not less than 10
days' prior written notice to the relevant Assignor specifying the time at
which such disposition is to be made and the intended sale price or other
consideration therefor, and shall be subject, for the 10 days after the giving
of such notice, to the right of the relevant Assignor or any nominee of such
Assignor to acquire the Collateral involved at a price or for such other
consideration at least equal to the intended sale price or other consideration
so specified. Any such disposition which shall be a public sale permitted by
such requirements shall be made upon not less than 10 days' prior written
notice to the relevant Assignor specifying the time and place of such sale and,
in the absence of applicable requirements of law, shall be by public auction
(which may, at the Collateral Agent's option, be subject to reserve), after
publication of notice of such auction (where required by applicable law) not
less than 10 days prior thereto. The Collateral Agent may, without notice or
publication, adjourn any public or private sale or cause the same to be
adjourned from time to time by announcement at the 


                                     -15-
<PAGE>   17

time and place fixed for the sale, and such sale may be made at any time or
place to which the sale may be so adjourned. To the extent permitted by any
such requirement of law, the Collateral Agent may bid for and become the
purchaser of the Collateral or any item thereof, offered for sale in accordance
with this Section 7.2 without accountability to the relevant Assignor. If,
under mandatory requirements of applicable law, the Collateral Agent shall be
required to make disposition of the Collateral within a period of time which
does not permit the giving of notice to the relevant Assignor as hereinabove
specified, the Collateral Agent need give such Assignor only such notice of
disposition as shall be reasonably practicable in view of such mandatory
requirements of applicable law. Each Assignor agrees to do or cause to be done
all such other acts and things as may be reasonably necessary to make such sale
or sales of all or any portion of the Collateral valid and binding and in
compliance with any and all applicable laws, regulations, orders, writs,
injunctions, decrees or awards of any and all courts, arbitrators or
governmental instrumentalities, domestic or foreign, having jurisdiction over
any such sale or sales, all at such Assignor's expense.

     7.3. Waiver of Claims. Except as otherwise provided in this Agreement,
EACH ASSIGNOR HEREBY WAIVES, TO THE EXTENT PERMITTED BY APPLICABLE LAW, NOTICE
AND JUDICIAL HEARING IN CONNECTION WITH THE COLLATERAL AGENT'S TAKING
POSSESSION OR THE COLLATERAL AGENT'S DISPOSITION OF ANY OF THE COLLATERAL,
INCLUDING, WITHOUT LIMITATION, ANY AND ALL PRIOR NOTICE AND HEARING FOR ANY
PREJUDGMENT REMEDY OR REMEDIES, and each Assignor hereby further waives, to the
extent permitted by law:

     (i) all damages occasioned by such taking of possession except any damages
which are the direct result of the Collateral Agent's gross negligence or
willful misconduct;

     (ii) all other requirements as to the time, place and terms of sale or
other requirements with respect to the enforcement of the Collateral Agent's
rights hereunder; and

     (iii) all rights of redemption, appraisement, valuation, stay, extension
or moratorium now or hereafter in force under any applicable law in order to
prevent or delay the enforcement of this Agreement or the absolute sale of the
Collateral or any portion thereof, and each Assignor, for itself and all who
may claim under it, insofar as it or they now or hereafter lawfully may, hereby
waives the benefit of all such laws.

Any sale of, or the grant of options to purchase, or any other realization
upon, any Collateral shall operate to divest all right, title, interest, claim
and demand, either at law or in equity, of the relevant Assignor therein and
thereto, and shall be a perpetual bar both at law and in equity against such
Assignor and against any and all Persons claiming or attempting to claim the
Collateral so sold, optioned or realized upon, or any part thereof, from,
through and under such Assignor.

     7.4. Application of Proceeds. (a) All moneys collected by the Collateral
Agent (or, to the extent the Pledge Agreement or any Additional Security
Document requires proceeds of collateral under such Security Document to be
applied in accordance with the provisions of this Agreement, the Pledgee under
such other Security Document) upon any sale or other disposition 


                                     -16-
<PAGE>   18

of the Collateral, together with all other moneys received by the Collateral
Agent hereunder, shall be applied as follows.

     (i) first, to the payment of all amounts owing the Collateral Agent of the
type described in clauses (iii) and (iv) of the definition of "Obligations";

     (ii) second, to the extent proceeds remain after the application pursuant
to the preceding clause (i), an amount equal to the outstanding Primary
Obligations shall be paid to the Secured Creditors as provided in Section
7.4(e) hereof, with each Secured Creditor receiving an amount equal to such
outstanding Primary Obligations or, if the proceeds are insufficient to pay in
full all such Primary Obligations, its Pro Rata Share of the amount remaining
to be distributed;

     (iii) third, to the extent proceeds remain after the application pursuant
to the preceding clauses (i) and (ii), an amount equal to the outstanding
Secondary Obligations shall be paid to the Secured Creditors as provided in
Section 7.4(e) hereof, with each Secured Creditor receiving an amount equal to
its outstanding Secondary Obligations or, if the proceeds are insufficient to
pay in full all such Secondary Obligations, its Pro Rata Share of the amount
remaining to be distributed; and

     (iv) fourth, to the extent proceeds remain after the application pursuant
to the preceding clauses (i) through (iii), inclusive, and following the
termination of this Agreement pursuant to Section 10.8(a) hereof, to the
relevant Assignor or to whomever may be lawfully entitled to receive such
surplus.

     (b) For purposes of this Agreement (x) "Pro Rata Share" shall mean, when
calculating a Secured Creditor's portion of any distribution or amount, that
amount (expressed as a percentage) equal to a fraction the numerator of which
is the then unpaid amount of such Secured Creditor's Primary Obligations or
Secondary Obligations, as the case may be, and the denominator of which is the
then outstanding amount of all Primary Obligations or Secondary Obligations, as
the case may be, (y) "Primary Obligations" shall mean (i) in the case of the
Credit Document Obligations, all principal of, and interest on, all Loans, all
Unpaid Drawings and all Fees and (ii) in the case of the Other Obligations, all
amounts due under such Interest Rate Protection Agreements or Other Hedging
Agreements (other than indemnities, fees (including, without limitation,
attorneys' fees) and similar obligations and liabilities) and (z) "Secondary
Obligations" shall mean all Obligations other than Primary Obligations.

     (c) When payments to Secured Creditors are based upon their respective Pro
Rata Shares, the amounts received by such Secured Creditors hereunder shall be
applied (for purposes of making determinations under this Section 7.4 only) (i)
first, to their Primary Obligations and (ii) second, to their Secondary
Obligations. If any payment to any Secured Creditor of its Pro Rata Share of
any distribution would result in overpayment to such Secured Creditor, such
excess amount shall instead be distributed in respect of the unpaid Primary
Obligations or Secondary Obligations, as the case may be, of the other Secured
Creditors, with each Secured Creditor whose Primary Obligations or Secondary
Obligations, as the case may be, have not been paid in full to receive an
amount equal to such excess amount multiplied by a fraction the numerator of
which is the unpaid Primary Obligations or Secondary Obligations, as 


                                     -17-
<PAGE>   19

the case may be, of such Secured Creditor and the denominator of which is the
unpaid Primary Obligations or Secondary Obligations, as the case may be, of all
Secured Creditors entitled to such distribution.

     (d) Each of the Secured Creditors, by their acceptance of the benefits
hereof, agrees and acknowledges that if the Lender Creditors are to receive a
distribution on account of undrawn amounts with respect to Letters of Credit
issued under the Credit Agreement (which shall only occur after all outstanding
Loans and Unpaid Drawings with respect to such Letters of Credit have been paid
in full), such amounts shall be paid to the Administrative Agent under the
Credit Agreement and held by it, for the equal and ratable benefit of the
Lender Creditors, as cash security for the repayment of Obligations owing to
the Lender Creditors as such. If any amounts are held as cash security pursuant
to the immediately preceding sentence, then upon the termination of all
outstanding Letters of Credit, and after the application of all such cash
security to the repayment of all Obligations owing to the Lender Creditors
after giving effect to the termination of all such Letters of Credit, if there
remains any excess cash, such excess cash shall be returned by the
Administrative Agent to the Collateral Agent for distribution in accordance
with Section 7.4(a) hereof.

     (e) All payments required to be made hereunder shall be made (x) if to the
Lender Creditors, to the Administrative Agent under the Credit Agreement for
the account of the Lender Creditors, and (y) if to the Other Creditors, to the
trustee, paying agent or other similar representative (each a "Representative")
for the Other Creditors or, in the absence of such a Representative, directly
to the Other Creditors.

     (f) For purposes of applying payments received in accordance with this
Section 7.4, the Collateral Agent shall be entitled to rely upon (i) the
Administrative Agent under the Credit Agreement and (ii) the Representative for
the Other Creditors or, in the absence of such a Representative, upon the Other
Creditors for a determination (which the Administrative Agent and each
Representative for any Other Creditors agree (or shall agree) to provide upon
request of the Collateral Agent) of the outstanding Primary Obligations and
Secondary Obligations owed to the Lender Creditors or the Other Creditors, as
the case may be. Unless it has actual knowledge (including by way of written
notice from a Lender Creditor or an Other Creditor) to the contrary, the
Administrative Agent and each Representative, in furnishing information
pursuant to the preceding sentence, and the Collateral Agent, in acting
hereunder, shall be entitled to assume that no Secondary Obligations are
outstanding. Unless it has actual knowledge (including by way of written notice
from an Other Creditor) to the contrary, the Collateral Agent, in acting
hereunder, shall be entitled to assume that no Interest Rate Protection
Agreements or Other Hedging Agreements are in existence.

     (g) It is understood that the Assignors shall remain jointly and severally
liable to the extent of any deficiency between the amount of the proceeds of
the Collateral and the aggregate amount of the Obligations.

     7.5. Remedies Cumulative. Each and every right, power and remedy hereby
specifically given to the Collateral Agent shall be in addition to every other
right, power and remedy specifically given under this Agreement, the other
Secured Debt Agreements or now or 


                                     -18-
<PAGE>   20

hereafter existing at law, in equity or by statute and each and every right,
power and remedy whether specifically herein given or otherwise existing may be
exercised from time to time or simultaneously and as often and in such order as
may be deemed expedient by the Collateral Agent. All such rights, powers and
remedies shall be cumulative and the exercise or the beginning of the exercise
of one shall not be deemed a waiver of the right to exercise any other or
others. No delay or omission of the Collateral Agent in the exercise of any
such right, power or remedy and no renewal or extension of any of the
Obligations shall impair any such right, power or remedy or shall be construed
to be a waiver of any Default or Event of Default or an acquiescence thereof.
No notice to or demand on any Assignor in any case shall entitle it to any
other or further notice or demand in similar or other circumstances or
constitute a waiver of any of the rights of the Collateral Agent to any other
or further action in any circumstances without notice or demand. In the event
that the Collateral Agent shall bring any suit to enforce any of its rights
hereunder and shall be entitled to judgment, then in such suit the Collateral
Agent may recover reasonable expenses, including reasonable attorneys' fees,
and the amounts thereof shall be included in such judgment.

     7.6. Discontinuance of Proceedings. In case the Collateral Agent shall
have instituted any proceeding to enforce any right, power or remedy under this
Agreement by foreclosure, sale, entry or otherwise, and such proceeding shall
have been discontinued or abandoned for any reason or shall have been
determined adversely to the Collateral Agent, then and in every such case the
relevant Assignor, the Collateral Agent and each holder of any of the
Obligations shall be restored to their former positions and rights hereunder
with respect to the Collateral subject to the security interest created under
this Agreement, and all rights, remedies and powers of the Collateral Agent
shall continue as if no such proceeding had been instituted.

                                  ARTICLE VIII

                                   INDEMNITY

     8.1. Indemnity. (a) Each Assignor jointly and severally agrees to
indemnify, reimburse and hold the Collateral Agent, each other Secured Creditor
and their respective successors, permitted assigns, employees, agents and
servants (hereinafter in this Section 8.1 referred to individually as
"Indemnitee," and collectively as "Indemnitees") harmless from any and all
liabilities, obligations, damages, injuries, penalties, claims, demands,
actions, suits, judgments and any and all costs, expenses or disbursements
(including reasonable attorneys' fees and expenses) (for the purposes of this
Section 8.1 the foregoing are collectively called "expenses") of whatsoever
kind and nature imposed on, asserted against or incurred by any of the
Indemnitees in any way relating to or arising out of this Agreement, any other
Secured Debt Agreement or any other document executed in connection herewith or
therewith or in any other way connected with the administration of the
transactions contemplated hereby or thereby or the enforcement of any of the
terms of, or the preservation of any rights under any thereof, or in any way
relating to or arising out of the manufacture, ownership, ordering, purchase,
delivery, control, acceptance, lease, financing, possession, operation,
condition, sale, return or other disposition, or use of the Collateral
(including, without limitation, latent or other defects, whether or not
discoverable), the violation of the laws of any country, state or other
governmental body or unit, any tort (including, 


                                     -19-
<PAGE>   21

without limitation, claims arising or imposed under the doctrine of strict
liability, or for or on account of injury to or the death of any Person
(including any Indemnitee), or property damage), or contract claim; provided
that no Indemnitee shall be indemnified pursuant to this Section 8.1(a) for
losses, damages or liabilities to the extent caused by the gross negligence or
willful misconduct of such Indemnitee. Each Assignor agrees that upon written
notice by any Indemnitee of the assertion of such a liability, obligation,
damage, injury, penalty, claim, demand, action, suit or judgment, the relevant
Assignor shall assume full responsibility for the defense thereof. Each
Indemnitee agrees to use its best efforts to promptly notify the relevant
Assignor of any such assertion of which such Indemnitee has knowledge.

     (b) Without limiting the application of Section 8.1(a) hereof, each
Assignor agrees, jointly and severally, to pay, or reimburse the Collateral
Agent for any and all reasonable fees, costs and expenses of whatever kind or
nature incurred in connection with the creation, preservation or protection of
the Collateral Agent's Liens on, and security interest in, the Collateral,
including, without limitation, all fees and taxes in connection with the
recording or filing of instruments and documents in public offices, payment or
discharge of any taxes or Liens upon or in respect of the Collateral, premiums
for insurance with respect to the Collateral and all other fees, costs and
expenses in connection with protecting, maintaining or preserving the
Collateral and the Collateral Agent's interest therein, whether through
judicial proceedings or otherwise, or in defending or prosecuting any actions,
suits or proceedings arising out of or relating to the Collateral.

     (c) Without limiting the application of Section 8.1(a) or (b) hereof, each
Assignor agrees, jointly and severally, to pay, indemnify and hold each
Indemnitee harmless from and against any loss, costs, damages and expenses
which such Indemnitee may suffer, expend or incur in consequence of or growing
out of any misrepresentation by any Assignor in this Agreement, any other
Secured Debt Agreement or in any writing contemplated by or made or delivered
pursuant to or in connection with this Agreement or any other Secured Debt
Agreement.

     (d) If and to the extent that the obligations of any Assignor under this
Section 8.1 are unenforceable for any reason, such Assignor hereby agrees to
make the maximum contribution to the payment and satisfaction of such
obligations which is permissible under applicable law.

     8.2. Indemnity Obligations Secured by Collateral; Survival. Any amounts
paid by any Indemnitee as to which such Indemnitee has the right to
reimbursement shall constitute Obligations secured by the Collateral. The
indemnity obligations of each Assignor contained in this Article VIII shall
continue in full force and effect notwithstanding the full payment of all of
the other Obligations and notwithstanding the full payment of all the Notes
issued under the Credit Agreement, the termination of all Interest Rate
Protection Agreements or Other Hedging Agreements and all Letters of Credit and
the payment of all other Obligations and notwithstanding the discharge thereof.


                                     -20-
<PAGE>   22

                                   ARTICLE IX

                                  DEFINITIONS

     The following terms shall have the meanings herein specified. Such
definitions shall be equally applicable to the singular and plural forms of the
terms defined.

     "Administrative Agent" shall have the meaning provided in the recitals of
this Agreement.

     "Agreement" shall mean this Security Agreement as the same may be
modified, supplemented or amended from time to time in accordance with its
terms.

     "Assignor" shall have the meaning provided in the first paragraph of this
Agreement.

     "Borrower" shall have the meaning provided in the recitals of this
Agreement.

     "Cash Collateral Account" shall mean a cash collateral account maintained
with, and in the sole dominion and control of, the Collateral Agent for the
benefit of the Secured Creditors.

     "Chattel Paper" shall have the meaning provided in the Uniform Commercial
Code as in effect on the date hereof in the State of New York.

     "Class" shall have the meaning provided in Section 10.2 of this Agreement.

     "Collateral" shall have the meaning provided in Section 1.1(a) of this
Agreement.

     "Collateral Agent" shall have the meaning provided in the first paragraph
of this Agreement.

     "Contract Rights" shall mean all rights of any Assignor under each
Contract, including, without limitation, (i) any and all rights to receive and
demand payments under any or all Contracts, (ii) any and all rights to receive
and compel performance under any or all Contracts and (iii) any and all other
rights, interests and claims now existing or in the future arising in
connection with any or all Contracts.

     "Contracts" shall mean all contracts between any Assignor and one or more
additional parties (including, without limitation, any Interest Rate Protection
Agreements or Other Hedging Agreements and any partnership agreements, joint
venture agreements, limited liability company agreements and licensing
agreements), but excluding any contract to the extent that the terms thereof
prohibit (after giving effect to any approvals or waivers) the assignment of,
or granting a security interest in, such contract (it being understood and
agreed, however, that notwithstanding the foregoing, all rights to payment for
money due or to become due pursuant to any such excluded contract shall be
subject to the security interests created by this Agreement).


                                     -21-
<PAGE>   23

     "Copyrights" shall mean any United States copyright owned by any Assignor,
including any registrations of any Copyrights, in the United States Copyright
Office or any foreign equivalent office, as well as any application for a
copyright registration now or hereafter made by any Assignor with the United
States Copyright Office or any foreign equivalent office.

     "Credit Agreement" shall have the meaning provided in the recitals of this
Agreement.

     "Credit Document Obligations" shall have the meaning provided in the
definition of "Obligations" in this Article IX.

     "Default" shall mean any event which, with notice or lapse of time, or
both, would constitute an Event of Default.

     "Documents" shall have the meaning provided in the Uniform Commercial Code
as in effect on the date hereof in the State of New York.

     "Equipment" shall mean any "equipment," as such term is defined in the
Uniform Commercial Code as in effect on the date hereof in the State of New
York, now or hereafter owned by any Assignor and, in any event, shall include,
but shall not be limited to, all machinery, equipment, furnishings, fixtures
and vehicles now or hereafter owned by any Assignor and any and all additions,
substitutions and replacements of any of the foregoing, wherever located,
together with all attachments, components, parts, equipment and accessories
installed thereon or affixed thereto.

     "Event of Default" shall mean any Event of Default under, and as defined
in, the Credit Agreement and shall in any event include, without limitation,
any payment default on any of the Other Obligations after the expiration of any
applicable grace period.

     "FCC License" shall have the meaning provided in Section 1.1 of this
Agreement.

     "General Intangibles" shall have the meaning provided in the Uniform
Commercial Code as in effect on the date hereof in the State of New York (and
shall include all partnership interests and all limited liability company and
membership interests).

     "Goods" shall have the meaning provided in the Uniform Commercial Code as
in effect on the date hereof in the State of New York.

     "Indemnitee" shall have the meaning provided in Section 8.1 of this
Agreement.

     "Instrument" shall have the meaning provided in the Uniform Commercial
Code as in effect on the date hereof in the State of New York.

     "Inventory" shall mean merchandise, inventory and goods, and all
additions, substitutions and replacements thereof, wherever located, together
with all goods, supplies, incidentals, packaging materials, labels, materials
and any other items used or usable in manufacturing, processing, packaging or
shipping same, in all stages of production -- from raw 


                                     -22-
<PAGE>   24

materials through work-in-process to finished goods -- and all products and
proceeds of whatever sort and wherever located and any portion thereof which
may be returned, rejected, reclaimed or repossessed by the Collateral Agent
from any Assignor's customers, and shall specifically include all "inventory"
as such term is defined in the Uniform Commercial Code as in effect on the date
hereof in the State of New York, now or hereafter owned by any Assignor.

     "Investment Property" shall have the meaning provided in the Uniform
Commercial Code as in effect on the date hereof in the State of New York.

     "Lender Creditors" shall have the meaning provided in the recitals of this
Agreement.

     "Lenders" shall have the meaning provided in the recitals of this
Agreement.

     "Liens" shall mean any security interest, mortgage, pledge, lien, claim,
charge, encumbrance, title retention agreement, lessor's interest in a
financing lease or analogous instrument in, of, or on any Assignor's property.

     "Marks" shall mean all right, title and interest in and to any trademarks,
service marks and trade names now held or hereafter acquired by any Assignor,
including any registration of any trademarks and service marks in the United
States Patent and Trademark Office or in any equivalent foreign office and any
trade dress including logos and/or designs used by any Assignor.

     "Obligations" shall mean (i) the full and prompt payment when due (whether
at the stated maturity, by acceleration or otherwise) of all obligations and
indebtedness (including, without limitation, indemnities, Fees and interest
thereon) of each Assignor to the Lender Creditors, whether now existing or
hereafter incurred under, arising out of, or in connection with the Credit
Agreement and the other Credit Documents to which such Assignor is a party
(including all such obligations and indebtedness of such Assignor under the
Subsidiaries Guaranty) and the due performance and compliance by such Assignor
with all of the terms, conditions and agreements contained in the Credit
Agreement and such other Credit Documents (all such obligations and liabilities
under this clause (i), except to the extent consisting of obligations or
indebtedness with respect to Interest Rate Protection Agreements or Other
Hedging Agreements, being herein collectively called the "Credit Document
Obligations"); (ii) the full and prompt payment when due (whether at the stated
maturity, by acceleration or otherwise) of all obligations and liabilities
owing by such Assignor to the Other Creditors under, or with respect to
(including by reason of the Subsidiaries Guaranty), any Interest Rate
Protection Agreement or Other Hedging Agreement, whether such Interest Rate
Protection Agreement or Other Hedging Agreement is now in existence or
hereafter arising, and the due performance and compliance by such Assignor with
all of the terms, conditions and agreements contained therein (all such
obligations and liabilities described in this clause (ii) being herein
collectively called the "Other Obligations"); (iii) any and all sums advanced
by the Collateral Agent in order to preserve the Collateral or preserve its
security interest in the Collateral; (iv) in the event of any proceeding for
the collection or enforcement of any indebtedness, obligations, or liabilities
of such Assignor referred to in clauses (i) and (ii) above, after an Event of
Default shall have occurred and be continuing, the reasonable expenses of
retaking, holding, preparing for sale or lease, selling or 


                                     -23-
<PAGE>   25

otherwise disposing of or realizing on the Collateral, or of any exercise by
the Collateral Agent of its rights hereunder, together with reasonable
attorneys' fees and court costs; and (v) all amounts paid by any Indemnitee as
to which such Indemnitee has the right to reimbursement under Section 8.1 of
this Agreement; it being acknowledged and agreed that the "Obligations" shall
include extensions of credit of the types described above, whether outstanding
on the date of this Agreement or extended from time to time after the date of
this Agreement.

     "Other Creditors" shall have the meaning provided in the recitals of this
Agreement.

     "Other Obligations" shall have the meaning provided in the definition of
"Obligations" in this Article IX.

     "Patents" shall mean any patent to which any Assignor now or hereafter has
title and any divisions or continuations thereof, as well as any application
for a patent now or hereafter made by any Assignor.

     "Permits" shall mean, to the extent permitted to be assigned by the terms
thereof or by applicable law, all licenses, permits, rights, orders, variances,
franchises or authorizations of or from any governmental authority or agency.

     "Primary Obligations" shall have the meaning provided in Section 7.4(b) of
this Agreement.

     "Pro Rata Share" shall have the meaning provided in Section 7.4(b) of this
Agreement.

     "Proceeds" shall have the meaning provided in the Uniform Commercial Code
as in effect in the State of New York on the date hereof or under other
relevant law and, in any event, shall include, but not be limited to, (i) any
and all proceeds of any insurance, indemnity, warranty or guaranty payable to
the Collateral Agent or any Assignor from time to time with respect to any of
the Collateral, (ii) any and all payments (in any form whatsoever) made or due
and payable to any Assignor from time to time in connection with any
requisition, confiscation, condemnation, seizure or forfeiture of all or any
part of the Collateral by any governmental authority (or any person acting
under color of governmental authority) and (iii) any and all other amounts from
time to time paid or payable under or in connection with any of the Collateral.

     "Receivables" shall mean any "account" as such term is defined in the
Uniform Commercial Code as in effect on the date hereof in the State of New
York, now or hereafter owned by any Assignor and, in any event, shall include,
but shall not be limited to, all of such Assignor's rights to payment for goods
sold or leased or services performed by such Assignor, whether now in existence
or arising from time to time hereafter, including, without limitation, rights
evidenced by an account, note, contract, security agreement, chattel paper, or
other evidence of indebtedness or security, together with (a) all security
pledged, assigned, hypothecated or granted to or held by such Assignor to
secure the foregoing, (b) all of any Assignor's right, title and interest in
and to any goods, the sale of which gave rise thereto, (c) all


                                     -24-
<PAGE>   26

guarantees, endorsements and indemnifications on, or of, any of the foregoing,
(d) all powers of attorney for the execution of any evidence of indebtedness or
security or other writing in connection therewith, (e) all books, records,
ledger cards, and invoices relating thereto, (f) all evidences of the filing of
financing statements and other statements and the registration of other
instruments in connection therewith and amendments thereto, notices to other
creditors or secured parties, and certificates from filing or other
registration officers, (g) all credit information, reports and memoranda
relating thereto and (h) all other writings related in any way to the
foregoing.

     "Representative" shall have the meaning provided in Section 7.4(e) of this
Agreement.

     "Required Secured Creditors" shall mean (i) the Required Lenders (or, to
the extent required by Section 13.12 of the Credit Agreement, each of the
Lenders) under the Credit Agreement so long as any Credit Document Obligations
remain outstanding and (ii) in any situation not covered by the preceding
clause (i), the holders of a majority of the outstanding principal amount of
the Other Obligations.

     "Requisite Creditors" shall have the meaning provided in Section 10.2 of
this Agreement.

     "Secondary Obligations" shall have the meaning provided in Section 7.4(b)
of this Agreement.

     "Secured Creditors" shall have the meaning provided in the recitals of
this Agreement.

     "Secured Debt Agreements" shall mean and include this Agreement, the other
Credit Documents and the Interest Rate Protection Agreements and Other Hedging
Agreements.

     "Significant Copyright" shall mean each Copyright listed in Annex F hereto
of any Assignor that is material to its business, financial condition or
property.

     "Significant Mark" shall mean each Mark listed on Annex D hereto of any
Assignor that is material to its business, financial condition or property.

     "Significant Patent" shall mean each Patent listed in Annex E hereto for
any Assignor that is material to its business, financial condition or property.

     "Syndication Agent" shall have the meaning provided in the recitals of
this Agreement.

     "Termination Date" shall have the meaning provided in Section 10.8 of this
Agreement.

     "Trade Secret Rights" shall have the meaning provided in Section 5.1 of
this Agreement.


                                     -25-
<PAGE>   27

     "UCC" shall mean the Uniform Commercial Code as in effect from time to
time in the relevant jurisdiction.

                                   ARTICLE X

                                 MISCELLANEOUS

     10.1. Notices. Except as otherwise specified herein, all notices,
requests, demands or other communications to or upon the respective parties
hereto shall be deemed to have been duly given or made when delivered to the
party to which such notice, request, demand or other communication is required
or permitted to be given or made under this Agreement, addressed as follows:

     (a)  if to any Assignor, at the address set forth opposite such Assignor's
signature below;

     (b)  if to the Collateral Agent, at:

          Bankers Trust Company
          One Bankers Trust Plaza
          New York, New York  10006
          Attention: Greg Shefrin
          Tel. No.: (212) 250-1724
          Fax. No.: (212) 250-7218

     (c)  if to any Lender Creditor, at such address as such Lender Creditor
shall have specified in the Credit Agreement;

     (d)  if to any Other Creditor, at such address as such Other Creditor
shall have specified in writing to each Assignor and the Collateral Agent;

or at such other address as shall have been furnished in writing by any Person
described above to the party required to give notice hereunder.

     10.2. Waiver; Amendment. None of the terms and conditions of this
Agreement may be changed, waived, modified or varied in any manner whatsoever
unless in writing duly signed by each Assignor directly effected thereby and
the Collateral Agent (with the written consent of the Required Secured
Creditors); provided, however, that any change, waiver, modification or
variance affecting the rights and benefits of a single Class of Secured
Creditors (and not all Secured Creditors in a like or similar manner) shall
require the written consent of the Requisite Creditors of such affected Class.
For the purpose of this Agreement, the term "Class" shall mean each class of
Secured Creditors, i.e., whether (x) the Lender Creditors as holders of the
Credit Document Obligations or (y) the Other Creditors as the holders of the
Other Obligations. For the purpose of this Agreement, the term "Requisite
Creditors" of any Class shall mean each of (x) with respect to the Credit
Document Obligations, the Required Lenders and (y) with respect to the Other
Obligations, the holders of at least a majority of all obligations 


                                     -26-
<PAGE>   28

outstanding from time to time under the Interest Rate Protection Agreements or
Other Hedging Agreements.

     10.3. Obligations Absolute. The obligations of each Assignor hereunder
shall remain in full force and effect without regard to, and shall not be
impaired by, (a) any bankruptcy, insolvency, reorganization, arrangement,
readjustment, composition, liquidation or the like of such Assignor; (b) any
exercise or non-exercise, or any waiver of, any right, remedy, power or
privilege under or in respect of this Agreement or any other Secured Debt
Agreement; or (c) any amendment to or modification of any Secured Debt
Agreement or any security for any of the Obligations; whether or not such
Assignor shall have notice or knowledge of any of the foregoing.

     10.4. Successors and Assigns. This Agreement shall be binding upon each
Assignor and its successors and assigns (although no Assignor may assign its
rights and obligations hereunder except in accordance with the provisions of
the Secured Debt Agreements) and shall inure to the benefit of and be
enforceable by the Collateral Agent and the Secured Creditors and their
respective successors and assigns. All agreements, statements, representations
and warranties made by each Assignor herein or in any certificate or other
instrument delivered by such Assignor or on its behalf under this Agreement
shall be considered to have been relied upon by the Secured Creditors and shall
survive the execution and delivery of this Agreement and the other Secured Debt
Agreements regardless of any investigation made by the Secured Creditors or on
their behalf.

     10.5. Headings Descriptive. The headings of the several sections of this
Agreement are inserted for convenience only and shall not in any way affect the
meaning or construction of any provision of this Agreement.

     10.6. Governing Law. THIS AGREEMENT AND THE RIGHTS AND OBLIGATIONS OF THE
PARTIES HEREUNDER SHALL BE CONSTRUED IN ACCORDANCE WITH AND BE GOVERNED BY THE
LAW OF THE STATE OF NEW YORK.

     10.7. Assignor's Duties. It is expressly agreed, anything herein contained
to the contrary notwithstanding, that each Assignor shall remain liable to
perform all of the obligations, if any, assumed by it with respect to the
Collateral and the Collateral Agent shall not have any obligations or
liabilities with respect to any Collateral by reason of or arising out of this
Agreement, nor shall the Collateral Agent be required or obligated in any
manner to perform or fulfill any of the obligations of any Assignor under or
with respect to any Collateral.

     10.8. Termination; Release. (a) After the Termination Date, this Agreement
shall terminate (provided that all indemnities set forth herein including,
without limitation, in Section 8.1 hereof shall survive such termination) and
the Collateral Agent, at the request and expense of the respective Assignor,
will promptly execute and deliver to such Assignor a proper instrument or
instruments (including Uniform Commercial Code termination statements on form
UCC-3) acknowledging the satisfaction and termination of this Agreement, and
will duly assign, transfer and deliver to such Assignor (without recourse and
without any representation or warranty) such of the Collateral as may be in the
possession of the Collateral Agent and as has not 


                                     -27-
<PAGE>   29

theretofore been sold or otherwise applied or released pursuant to this
Agreement. As used in this Agreement, "Termination Date" shall mean the date
upon which the Total Commitment and all Interest Rate Protection Agreements and
Other Hedging Agreements have been terminated, no Note is outstanding (and all
Loans have been repaid in full), all Letters of Credit have been terminated and
all Obligations then owing have been paid in full.

     (b) In the event that any part of the Collateral is sold in connection
with a sale permitted by Section 9.02 of the Credit Agreement (other than a
sale to any Assignor or a Subsidiary thereof) or otherwise released at the
direction of the Required Secured Creditors and the proceeds of such sale or
sales or from such release are applied in accordance with the provisions of the
Credit Agreement, to the extent required to be so applied, such Collateral will
be sold free and clear of the Liens created by this Agreement and the
Collateral Agent, at the request and expense of the relevant Assignor, will
duly assign, transfer and deliver to such Assignor (without recourse and
without any representation or warranty) such of the Collateral as is then being
(or has been) so sold or released and as may be in the possession of the
Collateral Agent and has not theretofore been released pursuant to this
Agreement.

     (c) At any time that an Assignor desires that the Collateral Agent take
any action to acknowledge or give effect to any release of Collateral pursuant
to the foregoing Section 10.8(a) or (b), such Assignor shall deliver to the
Collateral Agent a certificate signed by a principal executive officer of such
Assignor stating that the release of the respective Collateral is permitted
pursuant to Section 10.8(a) or (b), as the case may be.

     10.9. Counterparts. This Agreement may be executed in any number of
counterparts and by the different parties hereto on separate counterparts, each
of which when so executed and delivered shall be an original, but all of which
shall together constitute one and the same instrument. A set of counterparts
executed by all the parties hereto shall be lodged with each Assignor and the
Collateral Agent.

     10.10. Severability. Any provision of this Agreement which is prohibited
or unenforceable in any jurisdiction shall, as to such jurisdiction, be
ineffective to the extent of such prohibition or unenforceability without
invalidating the remaining provisions hereof, and any such prohibition or
unenforceability in any jurisdiction shall not invalidate or render
unenforceable such provision in any other jurisdiction.

     10.11. The Collateral Agent. The Collateral Agent will hold in accordance
with this Agreement all items of the Collateral at any time received under this
Agreement. It is expressly understood and agreed that the obligations of the
Collateral Agent as holder of the Collateral and interests therein and with
respect to the disposition thereof, and otherwise under this Agreement, are
only those expressly set forth in this Agreement and in Section 12 of the
Credit Agreement. The Collateral Agent shall act hereunder and thereunder on
the terms and conditions set forth herein and in Section 12 of the Credit
Agreement.

     10.12. Additional Assignors. It is understood and agreed that any
Subsidiary of the Borrower that is required to execute a counterpart of this
Agreement after the date hereof 


                                     -28-
<PAGE>   30

pursuant to the Credit Agreement shall become an Assignor hereunder by
executing a counterpart hereof and delivering the same to the Collateral Agent.

     10.13. Actions Requiring FCC Approval. (a) Notwithstanding anything to the
contrary contained in this Agreement, or any of the documents executed pursuant
hereto, the Collateral Agent will not take any action pursuant to this
Agreement, or any such documents, which would constitute or result in any
assignment of any FCC License or any transfer of control of the holder of any
FCC License if such assignment of such FCC License or such transfer of control
would require under then existing law (including the Communications Act or the
FCC Rules) the prior approval of the FCC, without first obtaining such
approval. In connection with this Section 10.13, the Collateral Agent shall be
entitled to rely upon the advise of FCC counsel of the Collateral Agent's
choice with respect to such assignment or transfer (including to determine
whether any such assignment or transfer has occurred or will occur and whether
or not prior approval of the FCC is required) whether or not the advice
rendered is ultimately determined to have been accurate.

     (b) If an Event of Default shall have occurred and be continuing, each
Assignor shall take any action which the Collateral Agent may request in the
exercise of its rights and remedies under this Agreement in order to transfer
or assign the Collateral to the Collateral Agent or to such one or more third
parties as the Collateral Agent may designate, or to a combination of the
foregoing. To enforce the provisions of this Section 10.13, after an Event of
Default shall have occurred and be continuing, the Collateral Agent is
empowered to request, and each Assignor hereby agrees to authorize, the
appointment of a receiver or trustee from any court of competent jurisdiction.
Such receiver or trustee shall be instructed to seek from the FCC (and any
other governmental authority) consent or approval as may be required by the
Communications Act and the FCC Rules for any assignment of the assets of or
transfer of control of any or all of the FCC Licenses or any Person whose
stock, partnership interest or other equity interest is subject to this
Agreement to the extent required for such trustee or receiver to assume such
control for the purpose of seeking a bona fide purchaser to whom such FCC
Licenses or other Collateral will be assigned or control of such entity
ultimately will be transferred. Each Assignor agrees, at such Assignor's cost
and expense, to cooperate with any such trustee or receiver, or at such
trustee's or receiver's direction, such purchaser and with the Collateral Agent
in the preparation, execution and filing of any applications or other documents
and providing any information that may be necessary or helpful in obtaining the
FCC's consent to the assignment or transfer to such trustee or receiver, or at
such trustee's or receiver's direction, such purchaser of the Collateral or any
of the FCC Licenses. To the fullest extent permitted under applicable law, each
Assignor hereby agrees to consent to and authorize any such transfer of control
upon the request of the Collateral Agent after the occurrence of and during the
continuation of an Event of Default and, without limiting any rights of the
Collateral Agent under this Agreement, to authorize the Collateral Agent to
nominate a trustee or receiver to assume control of the Collateral, subject
only to any required consent, approval or order of a court of competent
jurisdiction, the FCC or other governmental authorities, for the purposes of
effectuating the transactions contemplated in this Section 10.13(b). Such
trustee or receiver shall have all the rights and powers as provided to it by
law, court order or to the Collateral Agent under this Agreement. Each Assignor
shall cooperate fully and use its best efforts in obtaining the consent


                                     -29-
<PAGE>   31

of the FCC and the approval or consent of each other governmental authority
required to effectuate the foregoing.

     (c) Each Assignor shall use its best efforts to assist in obtaining the
consent or approval of the FCC, any court, and any other governmental
authority, if required, for any action or transaction contemplated by this
Agreement, including, without limitation, the preparation, execution and filing
with the FCC of the transferor's or assignor's portion of any application or
applications for consent to the transfer of control or assignment necessary or
appropriate under the FCC's policies, rules and regulations for approval of the
transfer or assignments of all or any portion of the Collateral.

     (d) Each Assignor hereby acknowledges and agrees that the FCC Licenses are
unique assets and that a violation of such Assignor's covenant to cooperate
with respect to the obtainment of any regulatory consents would result in
irreparable harm to the Collateral Agent for which monetary damages are not
readily ascertainable. Each Assignor further agrees that, because of the unique
nature of its undertakings in this Section 10.13, the same may be specifically
enforced, and such Assignor hereby waives, and agrees to waive, any claim or
defense that the Collateral Agent would have an adequate remedy at law for the
breach of such undertakings and any requirement for posting of a bond or other
certificate.

     (e) Without limiting the obligations of any Assignor hereunder in any
respect, each Assignor further agrees that if such Assignor, upon or after the
occurrence and during the continuance of an Event of Default, should fail or
refuse to execute any application or other document necessary or appropriate to
obtain any governmental consent necessary or appropriate for the exercise of
any right of the Collateral Agent hereunder, such Assignor agrees that, to the
fullest extent permitted by the Communications Act and the FCC Rules, such
application or other document may be executed on such Assignor's behalf by the
clerk of any court or other forum in any competent jurisdiction without notice
to such Assignor.

     (f) This Section 10.13 shall not limit any other rights of the Collateral
Agent or the Secured Creditors available under applicable law and consistent
with the Communications Act and the FCC Rules.

     10.14. Consent and Waiver. EACH ASSIGNOR HEREBY IRREVOCABLY CONSENTS TO
AND WAIVES ANY RIGHT TO OBJECT TO OR OTHERWISE CONTEST THE APPOINTMENT OF A
RECEIVER AFTER THE OCCURRENCE AND DURING THE CONTINUANCE OF AN EVENT OF
DEFAULT. EACH ASSIGNOR HEREBY GRANTS SUCH CONSENT AND WAIVER KNOWINGLY AFTER
HAVING DISCUSSED THE IMPLICATIONS THEREOF WITH COUNSEL, ACKNOWLEDGES THAT THE
UNCONTESTED RIGHT TO HAVE A RECEIVER APPOINTED FOR THE FOREGOING PURPOSES IS
CONSIDERED ESSENTIAL BY THE COLLATERAL AGENT AND THE SECURED CREDITORS IN
CONNECTION WITH THE ENFORCEMENT OF THEIR RIGHTS AND REMEDIES HEREUNDER AND
UNDER THE OTHER CREDIT DOCUMENTS, AND THE AVAILABILITY OF SUCH APPOINTMENT AS A
REMEDY UNDER THE FOREGOING CIRCUMSTANCES WAS A MATERIAL FACTOR IN INDUCING THE
LENDERS TO MAKE (AND COMMIT TO MAKE) LOANS TO THE 


                                     -30-
<PAGE>   32

BORROWER AND IN INDUCING THE OTHER CREDITORS TO ENTER INTO INTEREST RATE
PROTECTION AGREEMENTS AND OTHER HEDGING AGREEMENTS WITH THE BORROWER, AND
AGREES TO ENTER INTO ANY AND ALL STIPULATIONS IN ANY LEGAL ACTIONS, OR
AGREEMENTS OR OTHER INSTRUMENTS IN CONNECTION WITH THE FOREGOING AND TO
COOPERATE FULLY WITH THE COLLATERAL AGENT AND THE REQUIRED LENDERS, OR, THE
HOLDERS OF A MAJORITY OF THE OTHER OBLIGATIONS, AS THE CASE MAY BE, IN
CONNECTION WITH THE ASSUMPTION AND EXERCISE OF CONTROL BY THE RECEIVER OVER ALL
OR ANY PORTION OF THE COLLATERAL.

                                     * * *


                                     -31-
<PAGE>   33

     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed and delivered by their duly authorized officers as of the date first
above written.

Address:

3333 Lee Parkway, Suite 100                   PAGEMART WIRELESS, INC.,
Dallas, TX  75219                               as an Assignor
Attention:  G. Clay Myers
Telephone:  (214) 765-3510
Telecopier:  (214) 765-4961                   By
                                                -------------------------------
                                                Name:
                                                Title:


Accepted and Agreed to:

BANKERS TRUST COMPANY,
  as Collateral Agent


By    
  --------------------------------
  Name:
  Title:




<PAGE>   34

                                                                   ANNEX A
                                                                      TO
                                                             SECURITY AGREEMENT
                                  



                      SCHEDULE OF CHIEF EXECUTIVE OFFICES
                           AND OTHER RECORD LOCATIONS


<PAGE>   35

                                                                   ANNEX B
                                                                      TO
                                                             SECURITY AGREEMENT
                                  



                 SCHEDULE OF INVENTORY AND EQUIPMENT LOCATIONS


<PAGE>   36

                                                                   ANNEX C
                                                                      TO
                                                             SECURITY AGREEMENT
                                  



                     SCHEDULE OF TRADE AND FICTITIOUS NAMES

<PAGE>   37

                                                                   ANNEX D
                                                                      TO
                                                             SECURITY AGREEMENT



                               SCHEDULE OF MARKS

<PAGE>   38


                                                                   ANNEX E
                                                                      TO
                                                             SECURITY AGREEMENT
                                  



                              SCHEDULE OF PATENTS

<PAGE>   39

                                                                   ANNEX F
                                                                      TO
                                                             SECURITY AGREEMENT




                             SCHEDULE OF COPYRIGHTS

<PAGE>   40


                                                                   ANNEX G
                                                                      TO
                                                             SECURITY AGREEMENT

                                  



                        ASSIGNMENT OF SECURITY INTEREST
                    IN UNITED STATES TRADEMARKS AND PATENTS

     FOR GOOD AND VALUABLE CONSIDERATION, receipt and sufficiency of which are
hereby acknowledged, [Name of Assignor], a __________ corporation (the
"Assignor") with principal offices at ____________________________, hereby
assigns and grants to Bankers Trust Company, as Collateral Agent, with
principal offices at One Bankers Trust Plaza, 130 Liberty Street, New York, New
York 10006 (the "Assignee"), a security interest in (i) all of the Assignor's
right, title and interest in and to the United States trademarks, trademark
registrations and trademark applications (the "Marks") set forth on Schedule A
attached hereto, (ii) all of the Assignor's rights, title and interest in and
to the United States patents (the "Patents") set forth on Schedule B attached
hereto, in each case together with (iii) all Proceeds (as such term is defined
in the Security Agreement referred to below) and products of the Marks and
Patents, (iv) the goodwill of the businesses with which the Marks are
associated and (v) all causes of action arising prior to or after the date
hereof for infringement of any of the Marks and Patents or unfair competition
regarding the same.

     THIS ASSIGNMENT is made to secure the satisfactory performance and payment
of all the Obligations of the Assignor, as such term is defined in the Security
Agreement among the Assignor, the other assignors from time to time party
thereto and the Assignee, dated as of March 23, 1999 (as amended from time to
time, the "Security Agreement"). Upon the occurrence of the Termination Date
(as defined in the Security Agreement), the Assignee shall, upon such
satisfaction, execute, acknowledge, and deliver to the Assignor an instrument
in writing releasing the security interest in the Marks and Patents acquired
under this Assignment.



<PAGE>   41

                                                                        ANNEX G
                                                                         Page 2


     This Assignment has been granted in conjunction with the security interest
granted to the Assignee under the Security Agreement. The rights and remedies
of the Assignee with respect to the security interest granted herein are
without prejudice to, and are in addition to those set forth in the Security
Agreement, all terms and provisions of which are incorporated herein by
reference. In the event that any provisions of this Assignment are deemed to
conflict with the Security Agreement, the provisions of the Security Agreement
shall govern.



<PAGE>   42
                                                                        ANNEX G
                                                                         Page 3


     IN WITNESS WHEREOF, the undersigned have executed this Assignment as of
the ____ day of _________, ____.

                                     [NAME OF ASSIGNOR], Assignor



                                     By
                                        ---------------------------------------
                                        Name:
                                        Title:



                                     BANKERS TRUST COMPANY,
                                       as Collateral Agent, Assignee


                                     By
                                        ---------------------------------------
                                        Name:
                                        Title:

<PAGE>   43

STATE OF NEW YORK        )
                         ) ss.:
COUNTY OF NEW YORK       )



     On this ____ day of _________, ____, before me personally came ________
_________________ who, being by me duly sworn, did state as follows: that [s]he
is _______________ of [Name of Assignor], that [s]he is authorized to execute
the foregoing Assignment on behalf of said corporation and that [s]he did so by
authority of the Board of Directors of said corporation.

                                               -------------------------------
                                                         Notary Public



<PAGE>   44


STATE OF NEW YORK        )
                         ) ss.:
COUNTY OF NEW YORK       )



     On this ____ day of _________, ____, before me personally came ________
_____________________ who, being by me duly sworn, did state as follows: that
[s]he is __________________ of Bankers Trust Company that [s]he is authorized
to execute the foregoing Assignment on behalf of said corporation and that
[s]he did so by authority of the Board of Directors of said corporation.

                                                -------------------------------
                                                         Notary Public

<PAGE>   45

                                                                     Schedule A


<TABLE>
<CAPTION>
                                U.S. TRADEMARKS
                                ---------------

MARK                                REG. NO.                      REG. DATE
----                                --------                      ---------
<S>                             <C>                               <C>

</TABLE>

<PAGE>   46

                                                                     SCHEDULE B


<TABLE>
<CAPTION>
                                U.S. TRADEMARKS
                                ---------------

PATENT                             PATENT NO.                      ISSUE DATE
------                             ----------                      ----------
<S>                             <C>                                <C>


</TABLE>


<PAGE>   47

                                                                   ANNEX H
                                                                      TO
                                                             SECURITY AGREEMENT




                        ASSIGNMENT OF SECURITY INTEREST
                          IN UNITED STATES COPYRIGHTS



     WHEREAS, [Name of Assignor], a _______________ corporation (the
"Assignor"), having its chief executive office at ___________________________,
___________________________, is the owner of all right, title and interest in
and to the United States copyrights and associated United States copyright
registrations and applications for registration set forth in Schedule A
attached hereto;

     WHEREAS, BANKERS TRUST COMPANY, as Collateral Agent, having its principal
offices at One Bankers Trust Plaza, 130 Liberty Street, New York, New York
10006 (the "Assignee"), desires to acquire a security interest in said
copyrights and copyright registrations and applications therefor; and

     WHEREAS, the Assignor is willing to assign to the Assignee, and to grant
to the Assignee, a security interest in and lien upon the copyrights and
copyright registrations and applications therefor described above.

     NOW, THEREFORE, for good and valuable consideration, the receipt of which
is hereby acknowledged, and subject to the terms and conditions of the Security
Agreement, dated as of March 23, 1999, made by the Assignor, the other
assignors from time to time party thereto and the Assignee (as amended from
time to time, the "Security Agreement"), the Assignor hereby assigns to the
Assignee, and grants to the Assignee, a security interest in the copyrights and
copyright registrations and applications therefor set forth in Schedule A
attached hereto.

     This Assignment has been granted in conjunction with the security interest
granted to the Assignee under the Security Agreement. The rights and remedies
of the Assignee with respect to the security interest granted herein are
without prejudice to, and are in addition to those set forth in the Security
Agreement, all terms and provisions of which are incorporated herein by
reference. In the event that any provisions of this Assignment are deemed to
conflict with the Security Agreement, the provisions of the Security Agreement
shall govern.

<PAGE>   48

     Executed at New York, New York, the __ day of _________, ____.

                                     [NAME OF ASSIGNOR], as Assignor


                                     By
                                       ----------------------------------------
                                       Name:
                                       Title:



                                     BANKERS TRUST COMPANY, as
                                       Collateral Agent, Assignee


                                     By
                                       ----------------------------------------
                                       Name:
                                       Title:



<PAGE>   49

STATE OF NEW YORK        )
                         ) ss.:
COUNTY OF NEW YORK       )


     On this __ day of _________, ____, before me personally came ___________
_______________, who being duly sworn, did depose and say that [s]he is
___________________ of [Name of Assignor], that [s]he is authorized to execute
the foregoing Assignment on behalf of said corporation and that [s]he did so by
authority of the Board of Directors of said corporation.

                                                   -------------------------
                                                          Notary Public



<PAGE>   50

STATE OF NEW YORK        )
                         ) ss.:
COUNTY OF NEW YORK       )


     On this ____ day of _________, ____, before me personally came ________
_____________________ who, being by me duly sworn, did state as follows: that
[s]he is __________________ of Bankers Trust Company that [s]he is authorized
to execute the foregoing Assignment on behalf of said corporation and that
[s]he did so by authority of the Board of Directors of said corporation.

                                                ----------------------------
                                                       Notary Public

<PAGE>   51

                                                                     SCHEDULE A

<TABLE>
<CAPTION>
                                U.S. COPYRIGHTS
                                ---------------

         REGISTRATION             PUBLICATION
            NUMBERS                   DATE                   COPYRIGHT TITLE
         ------------           ---------------              ---------------
<S>                             <C>                          <C>


</TABLE>


<PAGE>   52

                               TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                                                               Page
                                                                                                               ----
<S>      <C>                                                                                                   <C>
ARTICLE I

         SECURITY INTERESTS.......................................................................................2

         1.1.  Grant of Security Interests........................................................................2
         1.2.  Power of Attorney..................................................................................3

ARTICLE II

         GENERAL REPRESENTATIONS, WARRANTIES AND COVENANTS........................................................3

         2.1.  Necessary Filings..................................................................................4
         2.2.  No Liens...........................................................................................4
         2.3.  Other Financing Statements.........................................................................4
         2.4.  Chief Executive Office, Record Locations...........................................................4
         2.5.  Location of Inventory and Equipment................................................................5
         2.6.  Recourse...........................................................................................5
         2.7.  Trade Names; Change of Name........................................................................6

ARTICLE III

         SPECIAL PROVISIONS CONCERNING RECEIVABLES;
         CONTRACT RIGHTS; INSTRUMENTS; CHATTEL PAPER..............................................................6

         3.1.  Additional Representations and Warranties..........................................................6
         3.2.  Maintenance of Records.............................................................................6
         3.3.  Direction to Account Debtors; Contracting Parties; etc.............................................7
         3.4.  Modification of Terms; etc.........................................................................7
         3.5.  Collection.........................................................................................7
         3.6.  Instruments........................................................................................8
         3.7.  Assignors Remain Liable Under Receivables..........................................................8
         3.9.  Further Actions....................................................................................8

ARTICLE IV

         SPECIAL PROVISIONS CONCERNING TRADEMARKS.................................................................9

         4.1.  Additional Representations and Warranties..........................................................9
         4.2.  Licenses and Assignments...........................................................................9
         4.3.  Infringements.....................................................................................10
         4.4.  Preservation of Marks.............................................................................10
         4.5.  Maintenance of Registration.......................................................................10
</TABLE>

                                      (i)
<PAGE>   53

<TABLE>
<S>      <C>                                                                                                   <C>
         4.6.  Future Registered Marks...........................................................................10
         4.7.  Remedies..........................................................................................10

ARTICLE V

         SPECIAL PROVISIONS CONCERNING
         PATENTS, COPYRIGHTS AND TRADE SECRETS...................................................................11

         5.1.  Additional Representations and Warranties.........................................................11
         5.2.  Licenses and Assignments..........................................................................11
         5.3.  Infringements.....................................................................................11
         5.4.  Maintenance of Patents or Copyright...............................................................11
         5.5.  Prosecution of Patent and Copyright Applications..................................................12
         5.6.  Other Patents and Copyrights......................................................................12
         5.7.  Remedies..........................................................................................12

ARTICLE VI

         PROVISIONS CONCERNING ALL COLLATERAL....................................................................12

         6.1.  Protection of Collateral Agent's Security.........................................................12
         6.2.  Warehouse Receipts Non-negotiable.................................................................13
         6.3.  Further Actions...................................................................................13
         6.4.  Financing Statements..............................................................................13
         6.5.  FCC Licenses......................................................................................13

ARTICLE VII

         REMEDIES UPON OCCURRENCE OF EVENT OF DEFAULT............................................................14

         7.1.  Remedies; Obtaining the Collateral Upon Default...................................................14
         7.2.  Remedies; Disposition of the Collateral...........................................................15
         7.3.  Waiver of Claims..................................................................................16
         7.4.  Application of Proceeds...........................................................................16
         7.5.  Remedies Cumulative...............................................................................18
         7.6.  Discontinuance of Proceedings.....................................................................19

ARTICLE VIII

         INDEMNITY...............................................................................................19

         8.1.  Indemnity.........................................................................................19
         8.2.  Indemnity Obligations Secured by Collateral; Survival.............................................20
</TABLE>

                                     (ii)
<PAGE>   54

<TABLE>
<S>      <C>                                                                                                   <C>
ARTICLE IX

         DEFINITIONS.............................................................................................20


ARTICLE X

         MISCELLANEOUS...........................................................................................26

         10.1.  Notices..........................................................................................26
         10.2.  Waiver; Amendment................................................................................26
         10.3.  Obligations Absolute.............................................................................27
         10.4.  Successors and Assigns...........................................................................27
         10.5.  Headings Descriptive.............................................................................27
         10.6.  Governing Law....................................................................................27
         10.7.  Assignor's Duties................................................................................27
         10.8.  Termination; Release.............................................................................27
         10.9.  Counterparts.....................................................................................28
         10.10.  Severability....................................................................................28
         10.11.  The Collateral Agent............................................................................28
         10.12.  Additional Assignors............................................................................28
         10.13.  Actions Requiring FCC Approval..................................................................29
         10.14.   Consent and Waiver.............................................................................30
</TABLE>

ANNEX A    Schedule of Chief Executive Offices/Record Locations
ANNEX B    Schedule of Inventory and Equipment Locations 
ANNEX C    Schedule of Trade and Fictitious Names 
ANNEX D    Schedule of Marks
ANNEX E    Schedule of Patents 
ANNEX F    Schedule of Copyrights
ANNEX G    Form of Assignment of Security Interest in Certain United States
           Trademarks and Patents
ANNEX H    Form of Assignment of Security Interest in United States Copyrights


                                     (iii)