EXHIBIT 10.55


                    AMENDED AND RESTATED INVESTMENT AGREEMENT

                                  by and among

                              MOTIENT CORPORATION,

                         MOBILE SATELLITE VENTURES LLC,


               TMI COMMUNICATIONS AND COMPANY, LIMITED PARTNERSHIP

                                       and

                           THE INVESTORS NAMED HEREIN


                                   dated as of
                                October 12, 2001







                                                                  EXECUTION COPY

                    AMENDED AND RESTATED INVESTMENT AGREEMENT



     AMENDED AND RESTATED INVESTMENT AGREEMENT,  dated as of October 12, 2001 by
and  among  MOTIENT  CORPORATION,  a  Delaware  corporation  ("Parent"),  MOBILE
SATELLITE  VENTURES LLC, a Delaware limited  liability  company  (formerly named
"Motient  Satellite  Ventures LLC," hereinafter  sometimes referred to as "Newco
LLC"), each of the existing  investors in Newco LLC identified under the caption
"EXISTING  INVESTORS"  on Schedule IV hereto (each,  an "Existing  Investor" and
collectively,  the "Existing Investors"), each of the new investors in Newco LLC
identified  under the caption "NOTE  INVESTORS" on Schedule III hereto (each,  a
"Note  Investor"  and  collectively,  the  "Note  Investors"),  each  of the new
investors in Newco LLC identified  under the caption "NEW INVESTORS" on Schedule
IV hereto (each, a "New Investor" and collectively, the "New Investors") and TMI
COMMUNICATIONS AND COMPANY, LIMITED PARTNERSHIP, a limited partnership organized
under the laws of the Province of Quebec ("TMI").  The Existing  Investors,  the
Note  Investors  and the New  Investors  are  referred  to  herein  each,  as an
"Investor" and collectively, as the "Investors".

                              W I T N E S S E T H :
                               - - - - - - - - - -

     WHEREAS,  Motient  Services  Inc., a Delaware  corporation  and an indirect
wholly-owned  subsidiary of Parent ("Sub"),  has been issued licenses by the FCC
to provide satellite  communications services (such licenses,  together with the
satellite and ground  assets,  the "Existing Sub Business") in the United States
and  surrounding  waters and airspace and has a license to provide such services
in the 1530-1559 MHz and 1631.5-1660.5 MHz band;

     WHEREAS, in June 2000, pursuant to an Investment Agreement dated as of June
22, 2000 (such  agreement,  as in effect on the date hereof,  referred to as the
"June  Investment  Agreement"),  Parent and the  Existing  Investors  formed and
funded Newco LLC, which entered into certain arrangements with Sub, including an
Asset Sale Agreement dated as of June 29, 2000 (the "Sub Asset Sale  Agreement")
(the transactions  involving Parent,  Sub, Newco LLC, the Existing Investors and
related  parties  consummated  in June  2000  pursuant  to the  June  Investment
Agreement  are  referred  to  herein as the  "June  Transactions",  and the June
Investment  Agreement,  the Sub Asset Sale  Agreement  and the other  agreements
entered  into in  connection  therewith  are  referred  to  herein  as the "June
Agreements");

     WHEREAS, in January 2001, pursuant to the January 2001 Investment Agreement
dated as of January 8, 2001 (such  agreement,  as in effect on the date  hereof,
referred to as the "January Investment Agreement"),  Parent, Newco LLC, TMI, the
Existing Investors and the New Investors entered into certain  arrangements with
TMI, including the TMI Asset Sale Agreements (as defined herein) and amended and
restated the Sub Asset Sale Agreement  (the January  Investment  Agreement,  the
Asset Sale Agreements (as defined herein) and the other agreements  entered into
in  connection  therewith,  in each case,  as in effect on the date hereof,  are
referred to herein as the "January Agreements");

     WHEREAS,  TMI,  which is  indirectly  wholly-owned  by BCE Inc., a Canadian
business  corporation ("BCE"), is the holder of a license issued by the Canadian
Government  for  L-Band  mobile  satellite  spectrum  and the  owner of  related
satellite,   ground  and  customer  assets  (collectively,   the  "Existing  TMI
Business");

     WHEREAS,  the  parties  wish for Newco LLC,  which is owned as set forth on
Schedule I hereto,  to be converted into a Delaware  limited  partnership at the
First Closing, to be named Mobile Satellite Ventures,  LP ("Newco LP"), with the
interests  of the members of Newco LLC being  converted  into the  interests  in
Newco LP reflected on Schedule II hereto;

     WHEREAS,  the parties hereto wish for Newco LP and TMI to  rationalize  and
restructure  the  operations of the satellite and related  ground systems of the
Existing Sub Business and the Existing TMI Business,  together with the spectrum
and licenses  (including  service and feeder  links,  satellite  orbit slots and
additional  spectrum  license  filings  in  the 2 GHz  bands),  customer  bases,
intellectual  property,  switches,  network and related  assets into a legal and
operational  structure  that supports and maximizes the economic  viability of a
regional  mobile  satellite  system,  subject  to  complying  with all U.S.  and
Canadian regulatory requirements;

     WHEREAS, BCE has entered into a Non-Interference Agreement with Newco; and

     WHEREAS the parties have  developed a network  operations  plan  reflecting
their  intentions as to certain  aspects of the  combination of the Existing Sub
Business and the Existing TMI Business;

     WHEREAS,  the  parties  hereto  wish  to  amend  and  restate  the  January
Investment  Agreement to provide for,  among other things,  (i) the issuance and
sale by  Newco LP of the  Convertible  Notes  (as  defined  herein)  to the Note
Investors at the First Closing (as defined herein), (ii) the consummation of the
transactions  contemplated by the Asset Sale Agreements  (that were entered into
in connection with the January Investment Agreement) at the First Closing, (iii)
the  elimination of the Investors  Option (as defined in the January  Investment
Agreement) and (iv) certain other changes as provided herein;

     NOW, THEREFORE, the parties hereto hereby agree as follows:

SECTION 1.        The First Closing.
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1.1.     Formation of Newco GP; Conversion of Newco LLC.
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     (a) At or prior to the First  Closing,  the  parties  shall form a Delaware
corporation  ("Newco GP"), to be named Mobile Satellite Ventures GP Inc., to act
as the  general  partner  of Newco LP.  Newco GP shall  have one class of common
stock,  which shall be owned by the Note  Investors and the limited  partners of
Newco  LP pro  rata in  accordance  with  their  Percentage  Interests  on an as
converted  basis,  in Newco LP.  The  charter  and  by-laws of Newco GP shall be
substantially in the forms of Exhibits A and B hereto,  and at the First Closing
the  entities  which  are to be  Limited  Partners  of  Newco  LP and  the  Note
Investors,  shall enter into the Newco GP Stockholders  Agreement in the form of
Exhibit C hereto.  At the First  Closing,  the entities  which are to be limited
partners in Newco LP and the Note Investors  shall purchase  shares of Newco GP,
execute all consents and other approvals,  and take all other actions reasonably
necessary to effect the conversion  and other actions  described in this Section
1.1. At the First  Closing,  Newco LLC shall convert into Newco LP in accordance
with Section 18-216 of the Delaware  Limited  Liability  Company Act and Section
17-217 of the Delaware  Revised Uniform Limited  Partnership Act (the "DRULPA").
The limited  partnership  agreement of Newco LP (the "Newco LP Agreement") shall
be  substantially  in the form of Exhibit D hereto,  except that prior to giving
effect to the  consummation  of the other  transactions to be consummated at the
First Closing, Newco LP shall be owned as set forth on Schedule II hereto.

     (b)  Notwithstanding  the foregoing,  if the conversion of Newco LLC into a
Delaware  limited  partnership  or its  continued  status as a Delaware  limited
partnership would or shall cause a materially adverse Canadian tax effect to TMI
due to a change in law or interpretation  under Canadian tax law, the parties in
good faith will undertake to effect the conversion or  continuation of Newco LLC
as a limited  partnership in a U.S.  jurisdiction  other than Delaware that will
provide the same Canadian tax effects intended by this Agreement to be conferred
on TMI by the  conversion  or  continuation  of Newco LLC as a Delaware  limited
partnership and will not otherwise have a Material Adverse Effect on any partner
in Newco LP. In that event,  references to "Delaware" and certain  provisions of
Delaware law herein and in the  Ancillary  Agreements  correspondingly  shall be
changed,  where appropriate,  to the name of that other U.S.  jurisdiction.  The
entities  which are to be partners in Newco LP shall  execute all  consents  and
other approvals, and take all other actions,  reasonably necessary to effect the
conversion described in the immediately preceding sentence. Any additional costs
or  expenses  incurred  by  the  parties  in  connection  with  such  change  of
jurisdiction shall be for the account of TMI.

     (c) At or prior to the  First  Closing,  Newco  shall  form a  wholly-owned
subsidiary  of Newco LP ("Newco  Sub") to hold the FCC  licenses  that are to be
transferred  by Sub  and  TMI to  Newco  or  Newco  Sub  under  the  Asset  Sale
Agreements.

1.2.     Purchase and Sale of the Convertible Notes.
- ---------------------------------------------------

     (a) At the First  Closing,  each Note  Investor  shall,  severally  and not
jointly (subject to the second sentence of Section 1.5(c)),  purchase from Newco
LP,  and  Newco LP shall  issue  and sell to such  Note  Investor,  subordinated
convertible  promissory notes (each a "Convertible  Note" and collectively,  the
"Convertible  Notes") in the respective  aggregate  principal  amount  specified
opposite such Note  Investor's name on Schedule III hereto at the purchase price
of 100% of the  principal  amount  thereof,  which shall  result in an aggregate
purchase price to be paid by the Note Investors for all of the Convertible Notes
to be purchased  by them at the First  Closing of Fifty Two Million Five Hundred
Thousand Dollars (US$52,500,000). Following the First Closing, Newco LP shall be
owned as set forth on Schedule V.

     (b) At the First Closing, Parent Sub shall purchase from Newco LP and Newco
LP shall issue and sell to Parent Sub a Convertible Note in the principal amount
of Two Million Five Hundred Thousand Dollars  ($2,500,000) at the purchase price
of  100% of the  principal  amount  thereof.  The  Convertible  Notes  shall  be
substantially in the form of Exhibit E hereto.

1.3.     Formation of TMI Sub; TMI Asset Sale; The TMI Interest.
- ---------------------------------------------------------------

     (a) At or prior to the  First  Closing,  TMI will  form a  special  purpose
Delaware  limited  partnership  ("TMI  Sub")  to hold  the  limited  partnership
interest in Newco LP described  opposite TMI Sub's name on Schedule II (the "TMI
Interest").

     (b) At the First Closing,  the  transactions  contemplated by the TMI Asset
Sale Agreements  shall be consummated,  including (i) the issuance to TMI of the
limited  partnership  interest in Newco LP described  opposite TMI Sub's name on
Schedule  II, (ii) the  issuance to TMI of a US $11.5  million  promissory  note
substantially  in the form of Exhibit F (the "TMI  Note"),  (iii) the payment by
Newco to TMI of US$7,500,000,  (iv) the transfer by TMI of a 33% equity interest
in Canadian Holdco to Newco and (v) the transfer by TMI of a 20% equity interest
in Canadian License Co. to Newco.

1.4.     Formation of Parent Sub; Sub Asset Sale; The Parent Interest.
- ---------------------------------------------------------------------

     (a) At or prior to the First  Closing,  Parent will form a special  purpose
Delaware  corporation  ("Parent Sub") to hold the limited  partnership  interest
(the  "Parent  Interest")  in Newco LP described  opposite  Parent Sub's name on
Schedule II and to purchase the Convertible  Note as contemplated by Section 1.2
hereof.

     (b) At the First Closing, the transactions  contemplated by the Amended and
Restated  Sub Asset  Sale  Agreement  shall be  consummated,  including  (i) the
issuance by Newco of a US $15 million  promissory note to Sub  substantially  in
the form of Exhibit G hereto  (the "MSI  Note") and (ii) the payment by Newco to
Sub of US$45,000,000.

1.5.     The First Closing.
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     (a) The closing of the  transactions  contemplated  by this  Section 1 (the
"First Closing") shall take place at the offices of Hogan & Hartson L.L.P., 8300
Greensboro Drive, Suite 1100, McLean,  Virginia as soon as practicable after the
receipt of all  third-party  and  governmental  consents and  approvals  and the
satisfaction of other conditions which are specified herein as conditions to the
First Closing or on such other date as shall be mutually  agreed by TMI,  Parent
and the Note  Investors (the "First  Closing  Date").  The parties shall use all
reasonable  efforts to  consummate  the First  Closing  Transactions  as soon as
practicable.

     (b) At the First  Closing the parties  shall execute and deliver (and cause
their affiliates to execute and deliver) the Ancillary  Agreements and the other
certificates,  documents  and  instruments  contemplated  hereby and thereby and
shall consummate the First Closing Transactions.  At the First Closing, Newco LP
shall  deliver  to each  Existing  Investor,  to TMI Sub  and to  Parent  Sub an
executed  copy of the Newco LP Agreement  evidencing  the Interest  held by such
person.

     (c) At the First  Closing,  Newco LP will deliver to each Note Investor the
Convertible  Note(s)  to be  purchased  by such Note  Investor  in the form of a
single  Convertible  Note (or such  greater  number  of  Convertible  Notes,  in
denominations  of at least $500,000,  or such lesser amount as shall be equal to
such Note  Investor's  purchase  price for its  Convertible  Note,  as such Note
Investor may request and as shall be reflected in Schedule III hereto) dated the
date of the First Closing and  registered in such Note  Investor's  name against
delivery by such Note Investor to Newco LP of the purchase price therefor, which
shall be paid by wire  transfer to an account  designated in writing by Newco at
least three business days prior to the First Closing. If any Note Investor shall
fail to make the payment  contemplated by the preceding  sentence (or shall fail
to  participate  in the First  Closing),  the other Note  Investors in such Note
Investor's  Investor Group (as shown on Schedule III) shall be obligated to make
up for the resulting shortfall.  If any such Investor Group shall fail to comply
with its obligations hereunder, the other Note Investors shall have the pro rata
right (but not the obligation) to make up for the resulting shortfall,  in which
case the  other  Note  Investor(s)  shall be deemed  to have  consented  to such
re-allocation of the purchase and sale of the Convertible Notes.

     (d) At the  First  Closing,  Newco  LP  will  deliver  to  Parent  Sub  the
Convertible  Note  to be  purchased  by  Parent  Sub in  the  form  of a  single
Convertible  Note dated the date of the First  Closing and  registered in Parent
Sub's name  against  delivery  by Parent Sub to Newco LP of the  purchase  price
therefor,  which  shall be paid by wire  transfer  to an account  designated  in
writing by Newco LP at least three business days prior to the First Closing.

     (e) At the First Closing, Newco LP shall deliver to each Existing Investor,
to TMI  Sub  and to  Parent  Sub an  executed  copy of the  Newco  LP  Agreement
evidencing the Interest held by such person.

     (f) At the First Closing, Newco GP shall deliver to each Existing Investor,
to each Note  Investor,  to TMI Sub and to Parent  Sub an  executed  copy of the
Newco GP Stockholders Agreement.

     (g) At the First  Closing,  the following  transactions  shall be deemed to
occur in the following order:

          (1) The transactions contemplated by Section 1.1 hereof (including the
     conversion of Newco LLC into Newco LP);

          (2) The transactions contemplated by Section 1.2 hereof (including the
     purchase and sale of the Convertible Notes);

          (3) The  transactions  contemplated  by the Amended and  Restated  Sub
     Asset Sale Agreement;

          (4) The transfer by Parent to Parent Sub of the Parent Interest;

          (5) The issuance to TMI of the TMI Interest;

          (6) The transfer by TMI of the TMI Interest to TMI Sub;

          (7) The  transactions  contemplated  by the  TMI-Canadian  License Co.
     Asset Sale Agreement;

          (8)  The  transfer  by TMI of 800  shares  (representing  80%)  of the
     capital stock of Canadian License Co. to Canadian Holdco.;

          (9) The transactions contemplated by the TMI-ULC Asset Sale Agreement;
     and

          (10) The  transactions  (other  than (5)  above)  contemplated  by the
     TMI-Newco Asset Sale Agreement.

1.6.     Conditions to First Closing.
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     (a) Conditions to the  Obligations of all Parties.  The  obligations of the
parties hereto to consummate the transactions  contemplated  hereby at the First
Closing are subject to the  satisfaction  of the  following  conditions:  (i) no
ruling,  order,   injunction,   decree,  statute,  rule  or  regulation  of  any
governmental  authority  shall  prevent  the  consummation  of the  transactions
contemplated  hereby;  provided,   however,  that  the  parties  shall  use  all
commercially reasonable efforts to cause any such decree, ruling,  injunction or
other  order to be  vacated  or  lifted;  (ii)  immediately  prior to the  First
Closing,  Newco's pre-closing  liabilities and financial  commitments as a whole
(excluding  those  arising out of this  Agreement or the  Ancillary  Agreements)
shall  not  exceed  the sum of cash on hand and Five  Hundred  Thousand  Dollars
($500,000);   and  (iii)  each  party  shall  have  delivered  any   appropriate
cross-receipts or similar documentation reasonably requested by another party.

     (b) Conditions to the Obligations of the Note Investors. The obligations of
each Note  Investor to consummate  the  transactions  contemplated  at the First
Closing  are  subject  to the  satisfaction  or  waiver,  on or before the First
Closing Date, of the following additional conditions:

          (i)  Representations,  Warranties and Covenants of Other Parties.  The
     representations and warranties of Parent and Newco LLC set forth in Section
     4 of this Agreement and of TMI set forth in Section 6 of this Agreement and
     the respective  representations and warranties of Parent, Newco LLC and TMI
     set forth in the Ancillary  Agreements  shall be true and correct as of the
     date when made and  (unless  made as of a  specified  date) as of the First
     Closing Date except for such breaches as would not have a Material  Adverse
     Effect on (w) Parent,  (x) Newco,  (y) the  Existing  Sub  Business and the
     Existing TMI Business  (taken as a whole),  or (z) the licenses or spectrum
     of either the Existing Sub Business or the Existing TMI Business; provided,
     however,  that if any of the  representations  and  warranties  are already
     qualified  in any  respect  as to  materiality  or as to  Material  Adverse
     Effect,  such  representation  or warranty  shall be true and correct as of
     such dates in all respects (i.e., as written).  Parent,  Newco LLC, and TMI
     shall have performed in all material  respects their  respective  covenants
     set  forth in this  Agreement  to be  performed  prior  to or at the  First
     Closing;  provided,  however,  that  if any of the  covenants  are  already
     qualified in any respect by materiality or as to Material  Adverse  Effect,
     such covenant shall have been performed in all respects (i.e., as written).
     Neither  Parent  nor Newco LLC shall  have  taken any  action  which  would
     violate any  provision of the Newco LLC Operating  Agreement.  At the First
     Closing,   Parent  shall   deliver  to  each  Note  Investor  an  officer's
     certificate, dated the First Closing Date and duly executed by an executive
     officer,  certifying  as  to  Parent's  and  Newco's  compliance  with  the
     conditions  applicable  to them set forth in this clause (i) and in clauses
     (ii),  (iii),  (iv),  (ix), (x), (xiii),  (xiv), and (xvii);  and TMI shall
     deliver to each Note  Investor an  officer's  certificate,  dated as of the
     First Closing Date and duly executed by an executive officer, certifying as
     to TMI's compliance with the conditions  applicable to it set forth in this
     clause (i) and in clauses (iv), (ix), (xi) (xii), (xiii), (xiv) and (xvii).

          (ii) LP Conversion;  Newco GP Stockholders  Agreement.  Newco GP shall
     have been formed and Newco LLC shall have been  converted  into Newco LP as
     contemplated by Section 1.1 hereof.  TMI Sub, Parent Sub, and each Existing
     Investor  shall have executed and delivered to such Note Investor the Newco
     GP Stockholders Agreement.

          (iii) LP Certificates. Newco GP shall have executed and filed with the
     Secretary of State of the State of Delaware the  certificate  of conversion
     (the "Conversion  Certificate") and certificate of limited partnership (the
     "LP Certificate"), each in the form attached hereto as Exhibit H.

          (iv)  Ancillary  Agreements.  The parties to the Ancillary  Agreements
     shall have  executed and delivered  such  agreements  substantially  in the
     forms  attached  as  Exhibits  hereto and shall be  prepared,  at the First
     Closing, to consummate the First Closing Transactions.

          (v) Opinions of Counsel to Parent and TMI.  Such Note  Investor  shall
     have  received  (x) an opinion or  opinions  of counsel  (which may include
     opinions  of the  general  counsel)  to Parent and  Newco,  dated the First
     Closing Date, reasonably satisfactory to MSV Investors, LLC (the "Lead Note
     Investor") with respect to matters  customarily  addressed by legal counsel
     in  connection  with  transactions  of the type  contemplated  hereby,  (y)
     opinions  of  counsel  to TMI  reasonably  satisfactory  to the  Lead  Note
     Investor with respect to matters customarily  addressed by legal counsel in
     connection  with  transactions of the type  contemplated  hereby and by the
     Ancillary  Agreements  (including without limitation,  as to matters (other
     than  priority)  relating to the Guaranty,  the Security  Agreement and the
     Pledge  Agreement),  and (z) opinions of regulatory counsel for TMI and for
     Parent and Newco  acceptable  to the Lead Note  Investor  in its good faith
     discretion.

          (vi) Board of Directors of Newco GP. Newco GP shall have  delivered to
     such Note Investor  evidence that the number of directors  comprising Newco
     GP's  board of  directors  has been fixed as  contemplated  by the Newco GP
     Stockholders  Agreement  and  that  the  persons  designated  by  the  Note
     Investors pursuant thereto shall have been elected to such board.

          (vii) Good Standing  Certificates.  Newco LLC shall have  delivered to
     such Note Investor a copy of a certificate of good standing,  dated as of a
     date not earlier than five days prior to the First Closing,  from the State
     of Delaware and the Commonwealth of Virginia.

          (viii)  Secretary's  Certificates.  TMI, TMI Sub, Parent,  Parent Sub,
     Newco GP and Sub shall have  delivered to such Note  Investor  certificates
     executed by their  respective  secretaries,  dated the First  Closing Date,
     each  certifying  (A) in the case of Newco GP, a copy of its and Newco LP's
     organizational  documents,  (B)  resolutions  of its  respective  Board  of
     Directors or Board of Managers  authorizing the  transactions  contemplated
     hereby and by the Ancillary  Agreements,  (C) incumbency  matters,  and (D)
     such  other  proceedings  relating  to  the  authorization,  execution  and
     delivery of this Agreement,  the Ancillary  Agreements and the transactions
     contemplated hereby and thereby as may be reasonably  requested by the Lead
     Note Investor.

          (ix) No Pending Action. No action,  suit,  investigation,  proceeding,
     temporary  restraining order,  preliminary or permanent injunction or other
     order or  decree  shall be  pending  or  threatened  in any  court or other
     tribunal or before any arbitrator or governmental authority which (i) could
     have a Material Adverse Effect on (x) any Transaction Party (other than any
     Note Investor), (y) the Existing Sub Business and the Existing TMI Business
     (taken as a whole) or (z) the  licenses or spectrum of either the  Existing
     Sub Business or the Existing  TMI Business or (ii)  presents a  substantial
     possibility  of preventing  the  consummation  of any material  transaction
     contemplated hereby or by any Ancillary Agreements.

          (x) FCC Approval.  The FCC Change of Control  Approval shall have been
     issued and become effective.

          (xi) CRTC  Approval.  The CRTC  Approval  shall have been  granted and
     shall have been issued and become effective.

          (xii)  Industry  Canada  Approval.  The  Industry  Canada  Transfer of
     License Approval shall have been issued and become effective.

          (xiii) Other  Consents and  Approvals.  Without  giving  effect to the
     application of or compliance  with the provisions of Section 2.4(b) of each
     of the Asset Sale Agreements (with the exception of the TMI-ULC Asset Sales
     Agreement,  to which this  proviso  refers to Section  3(b)  thereof),  the
     Transaction  Parties shall have received all governmental,  shareholder and
     third party consents and approvals  (including the consents of lenders, but
     excluding all FCC approvals,  CRTC approvals and Industry Canada  approvals
     not described in clauses (x), (xi) and (xii) above) which are material and,
     in the  reasonable  judgment  of  the  Lead  Note  Investor,  necessary  in
     connection with the transactions  contemplated  hereby and by the Ancillary
     Agreements,  including the  expiration  or  termination  of any  applicable
     waiting period under the  Hart-Scott-Rodino  Antitrust  Improvements Act of
     1976 (the "HSR Act").

          (xiv) No Material Adverse Effect.  Since the date hereof,  no Material
     Adverse  Effect  shall have  occurred,  nor shall any event or events  have
     occurred  which  would be  reasonably  likely  to have a  Material  Adverse
     Effect,  with  respect to (x) any  Transaction  Party  (other than any Note
     Investor),  (y) the  Existing  Sub  Business  and the Existing TMI Business
     (taken as a whole) or (z) the  licenses or spectrum of either the  Existing
     Sub Business or the Existing TMI Business.

          (xv) Fairness Opinion.  Parent shall have delivered to each Investor a
     copy of an opinion of Houlihan  Lokey  Howard & Zukin  Financial  Advisors,
     Inc.,  addressed to the board of directors of Motient Holdings Inc. and Sub
     of even date herewith accompanied by a letter confirming that each Investor
     is authorized to rely upon such opinion,  subject to all the qualifications
     and limitations set forth therein, and neither such opinion nor such letter
     shall have been withdrawn,  amended or revoked; provided, that if the First
     Closing  occurs  at any time  after 45 days  after  the  date  hereof,  the
     Investors  shall be entitled to request a  bring-down  of such opinion as a
     condition  to the  First  Closing  and  such  bring-down  opinion  shall be
     delivered  on  or  before  the  First   Closing  and  shall  be  reasonably
     satisfactory to each Investor.

          (xvi) Other Documents.  TMI, Parent, Newco LLC, Newco LP and Sub shall
     have delivered to such Note Investor such other documents as counsel to the
     Lead Note Investor may reasonably request.

          (xvii)  Encumbrances.  At the First  Closing,  all of the assets to be
     conveyed under the TMI Asset Sale Agreements shall be free and clear of any
     and all Encumbrances  including without limitation any Encumbrances held by
     BCE or its affiliates,  other than any Encumbrances  specifically permitted
     by the TMI Asset Sale Agreements.  At the First Closing,  all of the assets
     to be  conveyed  under the Amended and  Restated  Sub Asset Sale  Agreement
     shall  be free  and  clear  of any  and all  Encumbrances  other  than  any
     Encumbrances  specifically  permitted by the Amended and Restated Sub Asset
     Sale Agreement.

          (xviii)  TMI-Telesat  Letter  Agreement.  TMI and Telesat Canada shall
     have  performed  all of their  obligations  under  the  TMI-Telesat  Letter
     Agreement to be performed at or before the First Closing.

          (xix) Simultaneous  Purchase.  The obligation of each Note Investor to
     purchase its Convertible  Notes is expressly  conditioned upon the prior or
     substantially simultaneous purchase by each other Note Investor (other than
     any other Note  Investor  in such Note  Investor's  Investor  Group) of its
     respective  portion of the  Convertible  Notes as set forth on Schedule III
     hereto;  provided  that the  purchase by a Note  Investor  of another  Note
     Investor's  shortfall pursuant to 1.5(c) hereof shall not be deemed to be a
     failure to purchase for purposes of satisfying this condition.

          (xx) Satisfaction of Other Closing  Conditions.  The obligation of the
     Lead  Note  Investor  to  purchase  its  Convertible   Notes  is  expressly
     conditioned  upon all other conditions to the First Closing having occurred
     or having been waived by the respective parties.

          (xxi) No Termination  Event.  No events shall have occurred which give
     rise to a right of Newco to terminate  any of the  Ancillary  Agreements to
     which it is presently a party,  regardless  of whether  Newco has exercised
     such right.

          (xxii) Indenture  Release  Documentation.  Parent shall have submitted
     the documentation required by Section 11.05 of the Indenture to the Trustee
     (as  defined  in the  Indenture)  in order to have  Sub  released  from its
     obligation  under its Subsidiary  Guaranty (as defined in the Indenture) as
     contemplated by Section 10.18 hereof.

          (xxiii) BCE  Non-Interference  Amendment.  TMI shall have delivered to
     each  Note  Investor  a copy of an  amendment  to the BCE  Non-Interference
     Agreement  duly  executed by BCE  clarifying  that the  references  in such
     agreement  to  the  "Investment   Agreement"  are  to  this  Agreement  and
     references  in such  agreement to the  "Closing"  are to the First  Closing
     hereunder.  For certainty,  the failure to deliver such amendment shall not
     be deemed to be a breach of this  Agreement by TMI,  provided that TMI uses
     all reasonable commercial efforts to deliver such amendment.

     (c) Conditions to the  Obligations of Parent and Newco LLC. The obligations
of Parent and Newco LLC to consummate the  transactions  contemplated  hereby at
the First Closing are subject to the  satisfaction  or waiver,  on or before the
First Closing Date, of the following additional conditions:

          (i)  Representations,  Warranties  and Covenants of the Note Investors
     and TMI. The representations and warranties of each Note Investor set forth
     in  Section 5 of this  Agreement  and of TMI set forth in Section 6 of this
     Agreement  shall be true and  correct as of the date when made and  (unless
     made as of a specified  date) as of the First  Closing Date except for such
     breaches as would not have a Material  Adverse Effect on (x) Newco, (y) the
     Existing TMI Business and the Existing Sub Business (taken as a whole),  or
     (z) the  licenses or  spectrum  of the  Existing  TMI  Business;  provided,
     however,  that if any of the  representations  and  warranties  are already
     qualified  in any  respect  as to  materiality  or as to  Material  Adverse
     Effect,  such  representation  or warranty  shall be true and correct as of
     such dates in all respects (i.e.,  as written).  Each Note Investor and TMI
     shall have  performed in all material  respects its  covenants set forth in
     this Agreement to be performed prior to or at the First Closing;  provided,
     however,  that if any of the covenants are already qualified in any respect
     by materiality or as to Material  Adverse Effect,  such covenant shall have
     been performed in all respects  (i.e.,  as written).  At the First Closing,
     each Note Investor shall deliver to Parent an officer's certificate,  dated
     the  First  Closing  Date  and  duly  executed  by  an  executive  officer,
     certifying  as to such  Note  Investor's  compliance  with  the  conditions
     applicable  to it set forth in this clause (i) and in clauses  (iii),  (vi)
     and (x), and TMI shall  deliver to Parent an officer's  certificate,  dated
     the  First  Closing  Date  and  duly  executed  by  an  executive  officer,
     certifying as to TMI's compliance with the conditions  applicable to it set
     forth in this clause (i) and in clauses (iii),  (vi),  (viii),  (ix),  (x),
     (xi), (xiii), and (xiv).

          (ii) Newco LP Agreement;  Newco GP  Stockholders  Agreement.  TMI Sub,
     each  Existing  Investor and Newco GP shall have  executed and delivered to
     Parent Sub the Newco LP Agreement  and TMI Sub, each Note Investor and each
     Existing Investor shall have executed and delivered to Parent Sub the Newco
     GP Stockholders Agreement.

          (iii) Ancillary  Agreements.  The parties to the Ancillary  Agreements
     shall have executed and delivered such agreements substantially in the form
     attached  hereto as Exhibits and shall be prepared at the First  Closing to
     consummate the First Closing Transactions.

          (iv) Opinions of Counsel to TMI.  Parent and Newco shall have received
     opinions  of counsel to TMI  reasonably  satisfactory  to such  Parent with
     respect to matters  customarily  addressed by legal  counsel in  connection
     with  transactions  of the type  contemplated  hereby and by the  Ancillary
     Agreements  (including  without  limitation,  as  to  matters  (other  than
     priority)  relating to the Guaranty,  the Security Agreement and the Pledge
     Agreement),  and an opinion of  regulatory  counsel for TMI  acceptable  to
     Parent in its good faith discretion.

          (v)  Secretary's  Certificates.  Each Note Investor and TMI shall have
     delivered  to Parent a  certificate  executed by its  Secretary,  dated the
     First Closing Date,  certifying  (A)  resolutions of its Board of Directors
     authorizing the transactions  contemplated  herein, (B) incumbency matters,
     and (C) such other proceedings relating to the authorization, execution and
     delivery of this Agreement,  the Ancillary  Agreements and the transactions
     contemplated hereby and thereby as may be reasonably requested by Parent.

          (vi) No Pending Action. No action,  suit,  investigation,  proceeding,
     temporary  restraining order,  preliminary or permanent injunction or other
     order or  decree  shall be  pending  or  threatened  in any  court or other
     tribunal or before any arbitrator or governmental authority which (i) could
     have a Material  Adverse  Effect on (x) TMI,  (y) the Existing Sub Business
     and the  Existing  TMI  Business  (taken as a whole) or (z) the licenses or
     spectrum of the  Existing  TMI  Business,  or (ii)  presents a  substantial
     possibility  of preventing  the  consummation  of any material  transaction
     contemplated hereby or by any Ancillary Agreement.

          (vii) FCC Approval. The FCC Change of Control Approval shall have been
     issued and become effective.

          (viii) CRTC  Approval.  The CRTC Approval  shall have been granted and
     shall have been issued and become effective.

          (ix) Industry Canada Approval. The Industry Canada Transfer of License
     Approval shall have been issued and become effective.

          (x) Other Consents and Approvals.  The Transaction  Parties shall have
     received  all  governmental,  shareholder  and  third  party  consents  and
     approvals  (including consents of lenders, but excluding all FCC approvals,
     CRTC approval and Industry Canada approvals not described in clauses (vii),
     (viii) and (ix) above) which are material and, in the  reasonable  judgment
     of Parent,  necessary  in  connection  with the  transactions  contemplated
     hereby  and  by  the  Ancillary  Agreements  including  the  expiration  or
     termination of any applicable waiting period under the HSR Act;

          (xi) No Material  Adverse Effect.  Since the date hereof,  no Material
     Adverse  Effect  shall have  occurred,  nor shall any event or events  have
     occurred which would be reasonably likely to have a Material Adverse Effect
     with  respect to (x) Newco or TMI,  (y) the  Existing  Sub Business and the
     Existing TMI Business (taken as a whole) or (z) the licenses or spectrum of
     the Existing TMI Business.

          (xii) Conditions in Amended and Restated Sub Asset Sale Agreement. The
     conditions  to Sub's  obligations  under the Amended and Restated Sub Asset
     Sale Agreement shall have been satisfied or waived.

          (xiii) BCE Encumbrances. At the First Closing, all of the assets to be
     conveyed under the TMI Asset Sale Agreements shall be free and clear of any
     and all Encumbrances  including without limitation any Encumbrances held by
     BCE or its affiliates,  other than any Encumbrances  specifically permitted
     by the TMI Asset Sale Agreements.

          (xiv) TMI-Telesat Letter Agreement.  TMI and Telesat Canada shall have
     performed all of their obligations  under the TMI-Telesat  Letter Agreement
     to be performed at or before the First Closing.

          (xv) BCE  Non-Interference  Amendment.  TMI shall  have  delivered  to
     Parent a copy of an amendment to the BCE  Non-Interference  Agreement  duly
     executed by BCE  clarifying  that the  references in such  agreement to the
     "Investment  Agreement"  are to  this  Agreement  and  references  in  such
     agreement  to the  "Closing"  are  to  the  First  Closing  hereunder.  For
     certainty,  the failure to deliver such amendment shall not be deemed to be
     a breach of this  Agreement by TMI,  provided that TMI uses all  reasonable
     commercial efforts to deliver such amendment.

     (d)  Conditions  to the  Obligations  of  TMI.  The  obligations  of TMI to
consummate the transactions contemplated hereby at the First Closing are subject
to the  satisfaction  or waiver,  on or before the First  Closing  Date,  of the
following additional conditions:

          (i) Representations, Warranties and Covenants of Parent, Newco and the
     Note Investors.  The representations and warranties of Parent and Newco set
     forth in Section 4 of this Agreement and of the Note Investors set forth in
     Section 5 of this  Agreement  shall be true and correct as of the date when
     made and (unless made as of a specified  date) as of the First Closing Date
     except for such  breaches  as would not have a Material  Adverse  Effect on
     Newco or the Existing Sub Business;  provided,  however, that if any of the
     representations  and warranties are already  qualified in any respect as to
     materiality  or as to  Material  Adverse  Effect,  such  representation  or
     warranty shall be true and correct as of such dates in all respects  (i.e.,
     as written).  Newco LLC and each Note Investor  shall have performed in all
     material respects their respective covenants set forth in this Agreement to
     be performed prior to or at the First Closing;  provided,  however, that if
     any of the covenants are already qualified in any respect by materiality or
     as to Material  Adverse Effect,  such covenant shall have been performed in
     all respects  (i.e.,  as  written).  At the First  Closing  Newco LLC shall
     deliver to TMI an officer's  certificate,  dated the First Closing Date and
     duly  executed  by an  executive  officer,  certifying  as to  Newco  LLC's
     compliance  with the  conditions  applicable to it set forth in this clause
     (i) and in clauses (ii), (iii), (iv), (ix), (x), (xiii) and (xiv), and each
     Investor  shall  deliver to TMI an officer's  certificate,  dated the First
     Closing Date and duly  executed by an executive  officer,  certifying as to
     such Note Investor's  compliance  with the conditions  applicable to it set
     forth in this clause (i) and in clauses (iv), (ix) and (xiii).

          (ii) LP  Conversion;  Newco LP  Agreement.  Newco LLC shall  have been
     converted into Newco LP and Parent Sub, Newco GP and each Existing Investor
     shall have  executed and  delivered  to TMI Sub the Newco LP Agreement  and
     Parent  Sub,  each  Existing  Investor  and each Note  Investor  shall have
     executed and delivered to TMI Sub the Newco GP Stockholders Agreement.

          (iii) LP  Certificate.  Newco LP shall have adopted and filed with the
     Secretary of State of the State of Delaware the LP Certificate.

          (iv)  Ancillary  Agreements.  The parties to the Ancillary  Agreements
     shall have executed and delivered such agreements substantially in the form
     attached  hereto as Exhibits and shall be prepared at the First  Closing to
     consummate the First Closing Transactions.

          (v) Opinions of Counsel to Newco.  TMI shall have  received an opinion
     or opinions of counsel (which may include  opinions of the general counsel)
     to Parent and Newco, dated the First Closing Date, reasonably  satisfactory
     to TMI with respect to matters  customarily  addressed by legal  counsel in
     connection with transactions of the type contemplated hereby.

          (vi) Board of Directors of Newco GP. Newco GP shall have  delivered to
     TMI evidence  that the number of directors  comprising  Newco GP's board of
     directors has been fixed  pursuant to the Newco GP  Stockholders  Agreement
     and that the persons designated by TMI Sub pursuant thereto shall have been
     elected to such board.

          (vii) Good Standing  Certificates.  Newco LLC shall have  delivered to
     TMI a copy  of a  certificate  of good  standing,  dated  as of a date  not
     earlier  than  five  days  prior to the  First  Closing,  from the State of
     Delaware and the Commonwealth of Virginia. (viii) Secretary's Certificates.
     Each  Investor,  Parent and Newco shall have delivered to TMI a certificate
     executed  by its  respective  Secretary,  dated  the  First  Closing  Date,
     certifying  (A)  resolutions of its Board of Directors or Board of Managers
     authorizing the transactions  contemplated  herein, (B) incumbency matters,
     and (C) such other proceedings relating to the authorization, execution and
     delivery of this Agreement,  the Ancillary  Agreements and the transactions
     contemplated hereby and thereby as may be reasonably requested by TMI.

          (ix) No Pending Action. No action,  suit,  investigation,  proceeding,
     temporary  restraining order,  preliminary or permanent injunction or other
     order or  decree  shall be  pending  or  threatened  in any  court or other
     tribunal or before any arbitrator or governmental authority which (i) could
     have a Material  Adverse Effect on (x) Newco, (y) the Existing TMI Business
     and the  Existing  Sub  Business  (taken as a whole) or (z) the licenses or
     spectrum of the  existing  Sub  Business,  or (ii)  presents a  substantial
     possibility of preventing the consummation of the transactions contemplated
     hereby or by any Ancillary Agreement.

          (x) FCC  Approval.  The FCC  Change of  Control  Approval  shall  have
     been issued and become effective.

          (xi) CRTC  Approval.  The CRTC  Approval  shall have been  granted and
     shall have been issued and become effective.

          (xii)  Industry  Canada  Approval.  The  Industry  Canada  Transfer of
     License Approval shall have been issued and become effective.

          (xiii) Other  Consents and  Approvals.  Without  giving  effect to the
     application  of or compliance  with the provisions of Section 2.4(b) of the
     Amended and  Restated Sub Asset Sale  Agreement,  the  Transaction  Parties
     shall have received all governmental,  shareholder and third party consents
     and  approvals  (including  consents  of  lenders,  but  excluding  all FCC
     approvals,  CRTC approvals and Industry  Canada  approvals not described in
     clauses  (x),  (xi)  and  (xii)  above)  which  are  material  and,  in the
     reasonable  judgment of TMI,  necessary in connection with the transactions
     contemplated  hereby  and  by  the  Ancillary   Agreements   including  the
     expiration or termination  of any  applicable  waiting period under the HSR
     Act.

          (xiv) No Material Adverse Effect.  Since the date hereof,  no Material
     Adverse  Effect  shall have  occurred,  nor shall any event or events  have
     occurred  which  would be  reasonably  likely  to have a  Material  Adverse
     Effect,  with respect to (x) Newco or (y) the Existing Sub Business and the
     Existing TMI Business taken as a whole.

          (xv) Fairness Opinion. Parent shall have delivered to TMI a copy of an
     opinion  of  Houlihan  Lokey  Howard  &  Zukin  Financial  Advisors,  Inc.,
     addressed  to the board of directors  of Motient  Holdings  Inc. and Sub of
     even  date  herewith  accompanied  by  a  letter  confirming  that  TMI  is
     authorized to rely upon such opinion, subject to all the qualifications and
     limitations  set forth  therein,  and neither  such opinion nor such letter
     shall have been withdrawn,  amended or revoked; provided, that if the First
     Closing  occurs at any time after 45 days after the date hereof,  TMI shall
     be entitled to request a  bring-down  of such opinion as a condition to the
     First Closing and such  bring-down  opinion shall be delivered on or before
     the First Closing and shall be reasonably satisfactory to TMI.

          (xvi) Conditions in TMI Asset Sale Agreements. The conditions to TMI's
     obligations  under the TMI Asset Sale Agreements  shall have been satisfied
     or waived.

          (xvii)  Encumbrances.  At the First  Closing,  all of the assets to be
     conveyed under the Amended and Restated Sub Asset Sale Agreements  shall be
     free and  clear of any and all  Encumbrances  other  than any  Encumbrances
     specifically   permitted  by  the  Amended  and  Restated  Sub  Asset  Sale
     Agreement.

          (xviii) Indenture Release  Documentation.  Parent shall have submitted
     the documentation required by Section 11.05 of the Indenture to the Trustee
     (as  defined  in the  Indenture)  in order to have  Sub  released  from its
     obligation  under its Subsidiary  Guaranty (as defined in the Indenture) as
     contemplated by Section 10.18 hereof.

SECTION 2.        The Second Closing.
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2.1. The Investor  Interests.(a)  At the Second  Closing,  each New Investor and
each Existing Investor  (collectively,  the "Second Closing  Investors")  shall,
severally and not jointly  (subject to the second  sentence of Section  2.3(b)),
purchase from Newco LP, and Newco LP shall sell to such Second Closing Investor,
the number of Class A Preferred Units in Newco LP described opposite such Second
Closing  Investor's  name on Schedule IV (or such greater  number in  accordance
with Section 2.2)(collectively, the "Investor Interests") for the purchase price
indicated on Schedule IV, which shall result in an aggregate  purchase  price to
be paid by the Second Closing Investors for all of the Investor  Interests to be
purchased at the Second Closing of Fifty Million  Dollars  (US$50,000,000)  (the
"Investor  Purchase Price").  Following the Second Closing,  if no adjustment to
the Per Unit  Purchase  Price is made  pursuant to Section 2.2 hereof,  Newco LP
shall be owned as set forth on Schedule VI hereto.

     (b)  Notwithstanding  the other provisions of this Agreement,  in the event
that, at the request of Newco LP, prior to the Second  Closing any of the Second
Closing Investors (each, a "Pre-Funding  Investor")  provide  additional capital
("Pre-Funded  Capital") to Newco LP after the First Closing (whether in the form
of the purchase of  additional  Units or  otherwise),  then if such  Pre-Funding
Investor so elects at the time of the funding of such  Pre-Funded  Capital,  the
amount of the Pre-Funded  Capital funded by such  Pre-Funding  Investor shall be
deducted from the Investor  Purchase Price payable at the Second Closing by such
electing  Pre-Funding  Investor and the amount of Class A Preferred  Units to be
purchased  at  the  Second  Closing  by  such  Pre-Funding   Investor  shall  be
proportionately reduced;  provided, that in no event shall such elections reduce
the total Investor Purchase Price by more than $10,000,000 in the aggregate. For
the avoidance of doubt,  any funding of Pre-Funding  Capital shall not be deemed
to be the Second Closing for any purpose hereunder.

2.2.     Per Unit Purchase Price Adjustment.
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     (a) If the  Issuer  shall  declare or make any  distribution  of its assets
(including cash) to holders of any Units (except for  distributions to pay taxes
in  accordance  with  Section  8.2 of  the  Newco  LP  Agreement)  as a  partial
liquidating dividend, by way of return of capital or otherwise,  then the Second
Closing  Investors  shall be entitled to receive on the Second  Closing Date the
amount of such assets which,  if the Series A Preferred Units had been purchased
and issued immediately prior to such time, would have been payable to the holder
of such Class A  Preferred  Units on the record  date for the  determination  of
partners entitled to such distribution.  Notwithstanding  anything herein to the
contrary,  no adjustment in the Per Unit Purchase Price shall be made under this
Section  2.2(a) to the extent the Second  Closing  Investors  participate in any
such distribution of assets in accordance with this Section 2.2(a).

     (b) If Newco LP, at any time  from and  after  the First  Closing  Date and
prior  to  the  Second  Closing  Date,  subdivides  (by  any  split,   dividend,
recapitalization, reorganization, reclassification or otherwise) the outstanding
Units  into a  greater  number  of Units,  then,  after  the date of record  for
effecting such  subdivision,  the Per Unit Purchase Price in effect  immediately
prior to such subdivision shall be proportionately  reduced. If Newco LP, at any
time from and after the First Closing Date and prior to the Second Closing Date,
combines (by reverse split, recapitalization,  reorganization,  reclassification
or otherwise) the outstanding Units into a smaller number of Units,  then, after
the date of record for effecting such  combination,  the Per Unit Purchase Price
in  effect  immediately  prior  to such  combination  shall  be  proportionately
increased.

     (c) If Newco LP  shall,  at any time or from  time to time  after the First
Closing Date and prior to the Second  Closing Date,  issue any Units (as defined
in the Newco LP Agreement)(other than an issuance of Units as a dividend or in a
split of or  subdivision  in respect  of which the  adjustment  provided  for in
Section 2.2(d)  applies),  options to purchase or rights to subscribe for Units,
securities by their terms convertible into or exchangeable for Units, or options
to  purchase  or  rights  to  subscribe  for such  convertible  or  exchangeable
securities without consideration or for consideration per Unit less the Per Unit
Purchase Price in effect immediately prior to such issuance,  then such Per Unit
Purchase Price shall forthwith be lowered to a price equal to the price obtained
by multiplying:

          (i) the Per Unit  Purchase  Price in effect  immediately  prior to the
     issuance of such Units, options, rights or securities by

          (ii) a fraction  of which (x) the  denominator  shall be the number of
     Units outstanding on a fully-diluted  basis immediately after such issuance
     and  (y)  the  numerator  shall  be the  sum of (a)  the  number  of  Units
     outstanding on a fully-diluted basis immediately prior to such issuance and
     (b) the number of additional  Units which the aggregate  consideration  for
     the  number of Units so offered  would  purchase  at the Per Unit  Purchase
     Price.

For purposes of this Section 2.2,  "fully  diluted basis" shall be determined in
accordance  with the treasury stock method of computing  fully diluted  earnings
per Unit in accordance with GAAP

     (d) If Newco LP  shall,  at any time or from  time to time  after the First
Closing Date, directly or indirectly,  redeem, purchase or otherwise acquire any
Units, options to purchase or rights to subscribe for Units, securities by their
terms  convertible  into or  exchangeable  for Units (other than the Convertible
Notes which are redeemed  according to their  terms),  or options to purchase or
rights to subscribe  for such  convertible  or  exchangeable  securities,  for a
consideration  per Unit greater than the Per Unit Purchase  Price (plus,  in the
case of such  options,  rights,  or  securities,  the  additional  consideration
required  to be  paid  to  Newco  LP  upon  exercise,  conversion  or  exchange)
immediately  prior  to such  event,  then  the Per  Unit  Purchase  Price  shall
forthwith be lowered to a price equal to the price obtained by multiplying:

          (i) the Per Unit Purchase  Price in effect  immediately  prior to such
     event by

          (ii) a  fraction  of which (x) the  denominator  shall be the Per Unit
     Purchase Price  immediately prior to such event and (y) the numerator shall
     be the result of dividing:

               (1) the  product  of (A) the  number  of Units  outstanding  on a
          fully-diluted  basis and (B) the Per Unit Purchase Price, in each case
          immediately prior to such event, minus (2) the aggregate consideration
          paid by Newco LP in such  event  (plus,  in the case of such  options,
          rights,  or  convertible  or  exchangeable  securities,  the aggregate
          additional  consideration  to be  paid  by  Newco  LP  upon  exercise,
          conversion or exchange), by

               (2) the  number of Units  outstanding  on a  fully-diluted  basis
          immediately after such event.

     (e) For  the  purposes  of any  adjustment  of a Per  Unit  Purchase  Price
pursuant to paragraphs (a) and (b) of this Section 2.2, the following provisions
shall be applicable:

          (i) In the case of the issuance of Units for cash in a public offering
     or private placement, the consideration shall be deemed to be the amount of
     cash paid therefor before deducting any discounts, commissions or placement
     fees  payable  by  Newco  LP to  any  underwriter  or  placement  agent  in
     connection with the issuance and sale thereof.

          (ii) In the case of the issuance of Units for a consideration in whole
     or in part  other  than cash,  the  consideration  other than cash shall be
     deemed to be the fair market value  thereof as  determined in good faith by
     the board of directors of Newco GP.

          (iii) In the case of the  issuance of options to purchase or rights to
     subscribe  for  Units,  securities  by  their  terms  convertible  into  or
     exchangeable  for Units,  or options to purchase or rights to subscribe for
     such convertible or exchangeable securities:

               (1) the  aggregate  maximum  number  of  Units  deliverable  upon
          exercise of such options to purchase or rights to subscribe  for Units
          shall be deemed to have been issued at the time such options or rights
          were  issued  and  for a  consideration  equal  to  the  consideration
          (determined  in the  manner  provided  in  subparagraphs  (i) and (ii)
          above), if any, received by Newco LP upon the issuance of such options
          or rights plus the minimum  purchase price provided in such options or
          rights for the Units covered thereby;

               (2) the  aggregate  maximum  number  of  Units  deliverable  upon
          conversion of or in exchange for any such  convertible or exchangeable
          securities  or upon the  exercise  of options to purchase or rights to
          subscribe  for  such   convertible  or  exchangeable   securities  and
          subsequent conversion or exchange thereof shall be deemed to have been
          issued at the time such securities, options, or rights were issued and
          for a consideration  equal to the  consideration  received by Newco LP
          for any such securities and related  options or rights  (excluding any
          cash  received on account of accrued  interest or accrued  dividends),
          plus the additional consideration,  if any, to be received by Newco LP
          upon the conversion or exchange of such  securities or the exercise of
          any related  options or rights (the  consideration  in each case to be
          determined in the manner provided in paragraphs (i) and (ii) above);

               (3) on any  change  in  the  number  of  Units  deliverable  upon
          exercise of any such options or rights or  conversions of or exchanges
          for  such   securities,   other  than  a  change  resulting  from  the
          anti-dilution  provisions  thereof,  the  applicable Per Unit Purchase
          Price shall forthwith be readjusted to such Per Unit Purchase Price as
          would have been obtained had the adjustment  made upon the issuance of
          such options,  rights or securities not converted prior to such change
          or options or rights related to such securities not converted prior to
          such change been made upon the basis of such change; and

               (4) no further adjustment of the Per Unit Purchase Price adjusted
          upon the issuance of any such options, rights,  convertible securities
          or  exchangeable  securities  shall be made as a result of the  actual
          issuance of Units on the exercise of any such rights or options or any
          conversion or exchange of any such securities.

     (f)  Notwithstanding  anything  in this  Section  2.2 to the  contrary,  no
adjustment to the Per Unit Purchase Price shall be made upon the issuance of any
interests in Newco LP issued (i) pursuant to this  Agreement or the  Convertible
Notes or any of the transactions  contemplated  hereby or thereby (including the
conversion or redemption of the Convertible  Notes), (ii) in connection with the
acquisition of the business of another entity, whether by the purchase of equity
securities,  assets or otherwise, (iii) as part of an initial public offering or
other registered  underwritten  public offering of Newco LP's  securities,  (iv)
under  an  employee  compensation  plan  approved  by the  Newco GP and (v) upon
conversion or exchange of any Convertible Note.

     (g)  Within 10  Business  Days  after  the  occurrence  of any event  which
requires any  adjustment  of the Per Unit  Purchase  Price,  Newco LP shall give
written notice thereof to the Second Closing Investors.  Such notice shall state
the Per Unit Purchase Price  resulting from such  adjustment and shall set forth
in  reasonable  detail the method of  calculation  and the facts upon which such
calculation  is based.  Such  calculation  shall be certified by an  appropriate
officer of the general partner of Newco LP.

     (h) No adjustment of the Per Unit Purchase Price shall be made in an amount
of less  than 1% of the Per Unit  Purchase  Price  in  effect  at the time  such
adjustment  is  otherwise  required to be made,  but any such lesser  adjustment
shall be carried  forward  and shall be made at the time and  together  with the
next  subsequent  adjustment  which,  together with any  adjustments  so carried
forward, shall amount to not less than 1% of such Per Unit Purchase Price.

     (i) In the  event  of a  reduction  in the Per  Unit  Purchase  Price,  the
aggregate Investor Purchase Price shall not be reduced,  but the number of Class
A Preferred Units to the purchased by each Second Closing Investor at the Second
Closing  shall be  proportionately  increased  to reflect  the  reduced Per Unit
Purchase Price then in effect.

2.3.     The Second Closing.
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     (a) The closing of the  transactions  contemplated  by this  Section 2 (the
"Second  Closing")  shall take place at the  offices of Hogan & Hartson  L.L.P.,
8300  Greensboro  Drive,  Suite 1100,  McLean,  Virginia within ninety (90) days
following  the date (the "FCC Order  Finality  Date") that the FCC  Applications
Order shall have been issued and become a Final FCC Order  (unless the FCC Order
Finality Date shall occur subsequent to March 31, 2003, in which case the Second
Closing Investors shall have the option to proceed with the Second Closing until
June 30, 2003) or on such other date as shall be mutually agreed by Newco LP (by
vote of a majority of the  disinterested  directors  of Newco GP) and the Second
Closing Investors (the "Second Closing Date"). At the Second Closing the parties
shall  execute and deliver (and cause their  affiliates  to execute and deliver)
the  agreements   and  the  other   certificates,   documents  and   instruments
contemplated  hereby and shall consummate the transactions  contemplated by this
Section 2.

     (b) At the Second Closing,  Newco LP shall deliver to each Investor, to TMI
Sub and to Parent Sub an executed copy of the Newco LP Agreement  evidencing the
limited partnership interests in Newco LP (the "Interests") held by such person.
In the case of each Second Closing Investor, such delivery shall be made against
receipt at the Second Closing by Newco LP from such Second  Closing  Investor of
its portion of the Investor Purchase Price, which shall be paid by wire transfer
to an account  designated  in writing by Newco LP at least three  business  days
prior to the Second Closing.  If any Second Closing  Investor shall fail to make
the payment contemplated by the preceding sentence (or shall fail to participate
in the Second  Closing),  the other  Second  Closing  Investors  in such  Second
Closing  Investor's  Investor Group (as shown on Schedule IV) shall be obligated
to make up for the  resulting  shortfall.  If any  Investor  Group shall fail to
comply with its obligations hereunder,  the other Second Closing Investors shall
have the pro rata right (but not the  obligation)  to make up for the  resulting
shortfall, in which case the other Second Closing Investor(s) shall be deemed to
have consented to the Investor Interests being re-allocated appropriately.

     (c) At the  Second  Closing,  all of the  Convertible  Notes  that have not
theretofore   been   converted  into  Interests  by  the  holder  thereof  shall
automatically  convert  into  Interests  in Newco LP in  accordance  with  their
respective  terms and the Newco LP  Agreement  delivered  at the Second  Closing
pursuant to Section 2.3(b) shall  evidence such Interests in Newco LP;  provided
that at or prior to the Second  Closing,  Newco LP shall have  received at least
US$50 million in total funding from the Second  Closing  Investors  (through the
combination  of Pre-Funded  Capital and the Investor  Purchase Price paid at the
Second Closing).

     (d) At the  Second  Closing,  Newco LP shall  repay in cash all of the then
outstanding  principal of and accrued interest on the MSI Note and the TMI Note,
in accordance with their respective terms; provided that such repayment shall be
subject in all cases to the terms of the TMI Note and the MSI Note; and provided
further that in respect to such repayment of the MSI Note,  there shall not have
been an Event of  Default  under the  Convertible  Notes  pursuant  to which the
holders  thereof have declared the Convertible  Notes due and payable;  provided
further that at or prior to the Second Closing,  Newco LP shall have received at
least US$50 million in total funding from the Second Closing Investors  (through
the  combination of Pre-Funded  Capital and the Investor  Purchase Price paid at
the Second Closing).

2.4.     Conditions to the Second Closing.
- -----------------------------------------

     (a)  Conditions  to the  Obligations  of  Newco LP and the  Second  Closing
Investors.  The  obligations  of Newco LP and the Second  Closing  Investors  to
consummate  the  transactions  contemplated  hereby at the  Second  Closing  are
subject to the  satisfaction  of the  following  condition:  no  ruling,  order,
injunction,  decree,  statute, rule or regulation of any governmental  authority
shall  prevent  the  consummation  of  the  transactions   contemplated  hereby;
provided,  however,  that the  parties  shall  use all  commercially  reasonable
efforts  to cause  any such  decree,  ruling,  injunction  or other  order to be
vacated or lifted.

     (b)  Conditions to the  Obligations of the Second  Closing  Investors.  The
obligations  of each Second  Closing  Investor to  consummate  the  transactions
contemplated  hereby at the Second  Closing are subject to the  satisfaction  or
waiver,  on or before the  Second  Closing  Date,  of the  following  additional
conditions:

          (i)  Representations,  Warranties  and  Covenants  of  Newco  LP.  The
     representations  and  warranties of Newco LP set forth in Section 8 of this
     Agreement  shall be true and  correct in all  material  respects  as of the
     Second  Closing Date except for such  breaches as would not have a Material
     Adverse  Effect  on  Newco  LP;  provided,  however,  that  if  any  of the
     representations and warranties are already qualified as to Material Adverse
     Effect,  such  representation  or warranty  shall be true and correct as of
     such  dates in all  respects  (i.e.,  as  written).  Newco  LP  shall  have
     performed in all material  respects its  respective  covenants set forth in
     this Agreement to be performed prior to or at the Second Closing; provided,
     however,  that if any of the covenants are already qualified in any respect
     by materiality or as to Material  Adverse Effect,  such covenant shall have
     been performed in all respects (i.e., as written).  Newco LP shall not have
     taken  any  action  which  would  violate  any  provision  of the  Newco LP
     Agreement.  At the Second  Closing,  Newco LP shall  deliver to each Second
     Closing  Investor an officer's  certificate,  dated the Second Closing Date
     and duly executed by an executive officer of Newco GP, certifying as to the
     satisfaction  of the  condition  set forth in clause (xiii) below and as to
     Newco LP's  compliance  with the  conditions  applicable to it set forth in
     this clause (i) and in clauses (ii), (iii), (vii) and (viii).

          (ii)  Newco  LP  Agreement  Addendum.  The  addendum  to the  Newco LP
     Agreement  attached  hereto as Exhibit Y shall have been duly  executed  by
     Newco  LP and  all  Persons  (other  than  such  Second  Closing  Investor)
     necessary to make such addendum  binding on and enforceable  against all of
     the limited partners in Newco LP.

          (iii) Newco GP Stockholders  Agreement  Addendum.  The addendum to the
     Newco GP  Stockholders  Agreement  attached  hereto as Exhibit Z shall have
     been duly  executed  by Newco GP and all  Persons  (other  than such Second
     Closing   Investor)   necessary  to  make  such  addendum  binding  on  and
     enforceable against all of the stockholders of Newco GP.

          (iv)  Opinions of Counsel to Newco LP. Such  Second  Closing  Investor
     shall have  received  an  opinion of counsel to Newco LP,  dated the Second
     Closing Date,  reasonably  satisfactory to Telcom  Satellite  Ventures Inc.
     (the "Lead Second Closing  Investor")  with respect to matters  customarily
     addressed by legal  counsel in  connection  with  transactions  of the type
     contemplated hereby to occur in connection with the Second Closing.

          (v) Good Standing Certificates.  Newco LP shall have delivered to such
     Second Closing Investor a copy of a certificate of good standing,  dated as
     of a date not earlier than five days prior to the Second Closing Date, from
     the State of Delaware and the Commonwealth of Virginia.

          (vi) Secretary's  Certificates.  Newco LP shall have delivered to such
     Second Closing Investor certificates executed by the secretary of Newco GP,
     dated  the  Second  Closing  Date,  each  certifying  (A)  a  copy  of  the
     organizational documents of Newco LP and Newco GP, (B) resolutions of Newco
     GP's Board of Directors  authorizing the transactions  contemplated  hereby
     and by the Ancillary Agreements, (C) incumbency matters, and (D) such other
     proceedings  relating to the authorization,  execution and delivery of this
     Agreement,  the  Ancillary  Agreements  and the  transactions  contemplated
     hereby  and  thereby  as may be  reasonably  requested  by the Lead  Second
     Closing Investor.

          (vii) No Pending Action. No action, suit,  investigation,  proceeding,
     temporary  restraining order,  preliminary or permanent injunction or other
     order or  decree  shall be  pending  or  threatened  in any  court or other
     tribunal or before any arbitrator or governmental authority which (A) could
     have a  Material  Adverse  Effect on Newco LP or (B) seeks to  prevent  the
     consummation of the transactions  contemplated  hereby,  and is material in
     nature.

          (viii) FCC Approval. The FCC Applications Order shall have been issued
     and become a Final FCC Order on or before March 31, 2003.

          (ix) Other Consents and Approvals.  The Transaction Parties shall have
     received  all  governmental,  shareholder  and  third  party  consents  and
     approvals  (including the consents of lenders,  but excluding FCC approval,
     which is covered by clause  (vii)  above)  which are  material  and, in the
     reasonable  judgment  of the Lead Second  Closing  Investor,  necessary  in
     connection with the transactions  contemplated  hereby and by the Ancillary
     Agreements  including  the  expiration  or  termination  of any  applicable
     waiting period under the HSR Act.

          (x) No Material  Adverse  Effect.  Since the date hereof,  no Material
     Adverse  Effect shall have occurred with respect to Newco LP, nor shall any
     event or events have occurred  which would be  reasonably  likely to have a
     Material Adverse Effect on Newco LP.

          (xi) Other  Documents.  Newco LP shall have  delivered  to such Second
     Closing Investor such other documents as counsel to the Lead Second Closing
     Investor may reasonably request.

          (xii) Other Investors.  Each other Second Closing Investor (other than
     any  other  Second  Closing  Investor  in such  Second  Closing  Investor's
     Investor Group) shall be prepared to close simultaneously.

          (xiii) First Closing.  All  transactions  contemplated  hereby to have
     occurred at or in connection  with the First Closing shall have occurred as
     contemplated  hereby,  without any material  default by any party hereto or
     any waiver of, or  non-compliance  with, any of the conditions set forth in
     Section 1.6.

     (c) Conditions to the  Obligations of Newco LP. The obligations of Newco LP
to consummate  the  transactions  contemplated  hereby at the Second Closing are
subject to the satisfaction or waiver,  on or before the Second Closing Date, of
the  following  additional  conditions:  (i)  Representations,   Warranties  and
Covenants of the Second Closing Investors. The representations and warranties of
each Second Closing  Investor set forth in Section 5 of this Agreement  shall be
true and correct in all  material  respects as of the date when made and (unless
made as of a specified date) as of the Second Closing Date;  provided,  however,
that if any of the  representations  and warranties are already  qualified as to
Material  Adverse  Effect,  such  representation  or warranty  shall be true and
correct as of such dates in all respects (i.e., as written). Each Second Closing
Investor shall have  performed in all material  respects its covenants set forth
in this Agreement to be performed prior to or at the Second  Closing;  provided,
however,  that if any of the covenants  are already  qualified in any respect by
materiality  or as to Material  Adverse  Effect,  such covenant  shall have been
performed in all respects (i.e., as written).  At the Second Closing each Second
Closing Investor shall deliver to Newco LP an officer's  certificate,  dated the
Second Closing Date and duly executed by an executive officer,  certifying as to
such Second Closing Investor's  compliance with the conditions  applicable to it
set forth in this clause (i) and in clause (v).

               (ii) Newco LP  Agreement  Addendum.  The addendum to the Newco LP
          Agreement  attached  hereto as Exhibit Y shall have been duly executed
          by all Persons  (other than Newco LP)  necessary to make such addendum
          binding on and  enforceable  against  all of the  limited  partners in
          Newco LP.

               (iii) Newco GP Stockholder  Agreement  Addendum.  The addendum to
          the Newco GP Stockholders Agreement attached hereto as Exhibit Z shall
          have been duly  executed  by all  Persons  (other  than such Newco GP)
          necessary to make such addendum binding on and enforceable against all
          of the stockholders of Newco GP.

               (iv) Secretary's Certificates. Each Second Closing Investor shall
          have  delivered to Newco LP a certificate  executed by its  Secretary,
          dated the Second Closing Date, certifying (A) resolutions of its Board
          of Directors  authorizing the transactions  contemplated  herein,  (B)
          incumbency  matters,  and (C) such other  proceedings  relating to the
          authorization, execution and delivery of this Agreement, the Ancillary
          Agreements  to which it is a party and the  transactions  contemplated
          hereby and thereby as may be reasonably requested by Newco LP.

               (v)  No  Pending   Action.   No  action,   suit,   investigation,
          proceeding,  temporary  restraining  order,  preliminary  or permanent
          injunction  or other order or decree shall be pending or threatened in
          any court or other tribunal or before any  arbitrator or  governmental
          authority  which presents a substantial  possibility of preventing the
          consummation of any material transaction contemplated hereby or by any
          Ancillary Agreement.

               (vi) Consents and  Approvals.  The Second  Closing  Investors and
          Newco LP shall have received all  governmental,  shareholder and third
          party consents and approvals (including consents of lenders) which are
          material  and, in the  reasonable  judgment of Newco LP,  necessary in
          connection  with  the  transactions  contemplated  hereby  and  by the
          Ancillary  Agreements  including the  expiration or termination of any
          applicable waiting period under the HSR Act.

2.5.  Required  Consents.  Prior to the  Second  Closing  Date,  except  for any
transaction,  agreement, undertaking, activity or other action required in order
for Newco LP to perform its obligations specifically set forth in this Agreement
or any  Ancillary  Agreement  or for  Newco  LP to  exercise  any of its  rights
specifically  set forth  herein or  therein,  Newco LP shall not take any of the
following  actions,  without  the prior  consent  of the of  Existing  Investors
holding not less than 50.1% of the Percentage Interests in Newco LP then held by
all Existing Investors in Newco LP:

     (a)  neither  Newco LP nor any  Subsidiary  of Newco LP shall,  directly or
indirectly, make, create, incur, assume or suffer to exist any Lien upon or with
respect to any part of its  property or assets,  whether now owned or  hereafter
acquired, or offer or agree to do so, other than the following:

          (i) any Lien in favor of the holders of the Convertible Notes;

          (ii)  Liens to secure  Purchase  Money  Indebtedness  permitted  under
     Section  2.5(g)(i)  below,  provided  that such Liens cover only the assets
     acquired with such Purchase Money Indebtedness.

          (iii) Liens for taxes, fees, assessments or other governmental charges
     which are not delinquent or remain payable without penalty, unless the same
     are being  contested in good faith by appropriate  proceedings and adequate
     reserves in accordance with GAAP are maintained;

          (iv) carriers', warehousemen's, mechanics', landlords', materialmen's,
     repairmen's  or other  similar  Liens  arising  in the  ordinary  course of
     business  which do not secure Debt and are not delinquent or remain payable
     without penalty;

          (v) Liens  (other than any Lien  imposed by ERISA) on the  property of
     Newco LP incurred,  or pledges or deposits  required,  in  connection  with
     workmen's  compensation,  unemployment  insurance and other social security
     legislation;

          (vi) Liens on the property of Newco LP securing (1) the performance of
     bids,  trade  contracts  (other  than for  borrowed  money or other  Debt),
     leases,  statutory  obligations,  and (2)  obligations on surety and appeal
     bonds, and (3) other  obligations of a like nature incurred in the ordinary
     course of business  which do not secure Debt,  provided that all such Liens
     in the aggregate could not cause a Material Adverse Effect;

          (vii)  easements,   rights-of-way,   restrictions  and  other  similar
     encumbrances  incurred in the  ordinary  course of business  which,  in the
     aggregate,  are not  substantial  in  amount,  and which do not in any case
     materially  detract  from the  value of the  property  subject  thereto  or
     interfere with the ordinary conduct of the businesses of Newco LP;

          (viii) Liens on contract  rights  under  subscriber  equipment  leases
     sold, pledged or otherwise  transferred pursuant to any bona fide financing
     of such leases; and

          (ix)  Liens  to  secure  Debt  permitted  under  Section  2.5(g)(vii);
     provided  that all such Liens in the  aggregate  could not cause a Material
     Adverse Effect.

     (b)  neither  Newco LP nor any  Subsidiary  of Newco LP shall,  directly or
indirectly,  (i) sell, assign,  lease, convey,  transfer or otherwise dispose of
(whether  in one or a series of  transactions)  any of its  assets,  business or
property,  (including accounts and notes receivable) (with or without recourse),
or enter into equipment sale-leaseback transactions or (ii) merge or consolidate
with any other  Person,  or enter into any  agreement to do any of the foregoing
described in clauses (i) or (ii) except for the following:

          (i) sales,  transfers,  or other  dispositions of inventory,  or used,
     worn-out  or surplus  property,  or property of no further use to Newco LP,
     all in the ordinary course of business;

          (ii) sales,  transfers,  or other  dispositions  of  equipment  in the
     ordinary  course of business to the extent that such equipment is exchanged
     for credit against the purchase price of similar  replacement  equipment or
     the proceeds of such sale are reasonably  promptly  applied to the purchase
     price of such replacement equipment;

          (iii)  sales,  transfers,  or  other  dispositions  of  communications
     services,   capacity  or  equipment  pursuant  to  the  customer  contracts
     providing for the sale of communications services, capacity or equipment in
     the ordinary course of business;

          (iv) sales, transfers, or other dispositions of assets in the ordinary
     course of business  having a fair market value not  exceeding  $500,000 per
     item or $1,000,000 in the  aggregate in any fiscal year  (excluding  sales,
     transfers and  dispositions  theretofore  approved in  accordance  with the
     terms hereof in such fiscal year);

          (v) sales,  transfers or other  dispositions  of contract rights under
     subscriber  equipment  leases  pursuant to any bona fide  financing of such
     leases permitted under Section 2.5(g) below;

          (vi) non-exclusive licenses of technology and other intangible assets,
     excluding spectrum licenses;


          (vii) sales of mobile earth terminals and related equipment, and other
     inventory;

          (viii) sales,  transfers,  or other dispositions of assets as a result
     of the  combination  and  integration  of the Existing Sub Business and the
     Existing TMI Business as  contemplated  by the Operations  Plan,  including
     without  limitation  the  sale,  transfer  or  other  disposition  of:  (y)
     duplicative or  unnecessary  assets,  or (z) assets in connection  with the
     closing of  facilities  and  reductions  in  workforce;  provided that such
     disposition  does not  include a  disposition  of the FCC  Licenses  or the
     Canadian Licenses;

          (ix) any wholly-owned Subsidiary of Newco LP may merge, consolidate or
     combine with or into,  or transfer (for no  consideration)  assets to Newco
     LP;   provided  that  Newco  LP  shall  be  the   continuing  or  surviving
     corporation; and

          (x) any wholly-owned  Subsidiary of Newco LP may sell, lease, transfer
     or  otherwise  dispose  of  any  or  all  of  its  assets  (upon  voluntary
     liquidation or otherwise), to another wholly-owned Subsidiary.

     (c)  neither  Newco LP nor any  Subsidiary  of Newco LP shall,  directly or
indirectly,  make or  acquire  any  Investment  in any  Person  other  than  the
following:

          (i)  Investments  in Persons which are  wholly-owned  Subsidiaries  of
     Newco LP (including Newco Sub (as defined in the Investment  Agreement)) on
     the First Closing Date;

          (ii) Investments in Mobile Satellite Ventures (Canada) Inc. and Mobile
     Satellite Ventures Holdings (Canada) Inc. as required by the Capacity Lease
     Agreement,  the Rights and Services Agreement or the Canadian  Shareholders
     Agreement (as such terms are defined in the Investment Agreement);

          (iii) Cash Equivalents; and

          (iv) any Investment not otherwise  permitted by the foregoing  clauses
     (i),  (ii) and (iii)  if,  immediately  after  such  Investment  is made or
     acquired,  the  aggregate net book value (or  aggregate  cost  thereof,  if
     greater than book value at the time of  determination)  of all  Investments
     permitted by this clause (iii) does not exceed $2,000,000.

     (d)  neither  Newco LP nor any  Subsidiary  of Newco  LP  shall  repay  any
outstanding  Debt to  holders  of  equity  securities  of  Newco LP  except  for
repayments  under  the  Convertible  Notes,  repayments  under  the TMI Note and
repayments under the MSI Note, each in accordance with their respective terms.

     (e) other than Investments  permitted by Section 2.5(c)(ii),  neither Newco
LP nor any  Subsidiary of Newco LP shall,  directly or  indirectly,  (i) pay any
funds  to or for  the  account  of any  Affiliate  which  is not a  wholly-owned
Subsidiary of Newco LP, (ii) make any investment in any Affiliate which is not a
wholly-owned  Subsidiary  of  Newco  LP  (whether  by  acquisition  of  stock or
indebtedness,  by  loan,  advance,  transfer  of  property,  guarantee  or other
agreement to pay,  purchase or service,  directly or  indirectly,  any Debt,  or
otherwise),  (iii) lease,  sell,  transfer or  otherwise  dispose of any assets,
tangible or intangible,  to any Affiliate which is not a wholly-owned Subsidiary
of Newco LP, or (iv) except in the ordinary  course of business  consistent with
past  practice,  participate  in,  or  effect,  any other  transaction  with any
Affiliate  which is not a  wholly-owned  Subsidiary  of Newco LP, except in each
case on an  arm's-length  basis on terms  at least as  favorable  to Newco LP as
could have been obtained from a third party that was not an Affiliate.

     (f) neither  Newco LP nor any  Subsidiary  of Newco LP shall (i) declare or
make any dividend  payment or other  distribution of assets,  properties,  cash,
rights,  obligations  or  securities on account of any Units of any class of its
equity,  or (ii) redeem,  repurchase or otherwise acquire for value any Units of
its equity or any  warrants,  rights or options to acquire  such  Units,  now or
hereafter  outstanding,  in either case  except as  provided in the  Convertible
Notes or in the Newco LP Agreement.

     (g) neither Newco LP nor any  Subsidiary  of Newco LP shall create,  incur,
assume,  guaranty,  suffer to exist,  or otherwise  become or remain directly or
indirectly liable with respect to, any Debt, other than the following:

          (i) Purchase Money Indebtedness not to exceed  US$9,000,000 at any one
     time outstanding;

          (ii)  accounts  payable to trade  creditors for goods and services and
     current  operating  liabilities  (not the result of the borrowing of money)
     incurred in the ordinary course of Newco LP's business, as the case may be,
     in accordance  with  customary  terms and paid within the  specified  time,
     unless contested in good faith by appropriate  proceedings and reserved for
     in accordance with GAAP;

          (iii) income taxes payable and deferred taxes;

          (iv) accrued expenses and deferred income;

          (v) Debt  outstanding  as of the First Closing Date that is identified
     and quantified on Exhibit B to the Convertible Notes;

          (vi) Debt  incurred  to finance  in-orbit  insurance  in an  aggregate
     amount outstanding at any time not to exceed $5,000,000;

          (vii) any other Debt incurred after First Closing Date;  provided that
     the aggregate  outstanding  principal  amount of all such Debt shall not at
     any time exceed $2,000,000 outstanding; and

     (h) neither Newco LP nor any Subsidiary of Newco LP shall (i) amend, alter,
repeal or otherwise modify, or consent to the amendment,  alteration,  repeal or
other  modification  of,  the FCC  Licenses  or (ii)  amend,  alter,  repeal  or
otherwise  modify,  or consent  to the  amendment,  alteration,  repeal or other
modification of, any agreements relating to the Canadian Licenses,  or waive any
contractual  rights  thereto;  except  in each  case,  amendments,  alterations,
repeals,  or other  modifications  or  waivers  (y)  which do not have  Material
Adverse  Effect on Newco LP, or (z)  required by any law,  rule,  regulation  or
order of any Government Authority.

     (i) Newco LP shall not permit the  removal  of its  general  partner or the
appointment of a replacement general partner.

SECTION 3.        Parent Conversions.
- ------------------------------------

3.1.     Parent Conversions.
- ---------------------------

     (a) The Investor  Group  Designee  designated by each of the three Existing
Investor's  Investor  Groups  indicated on Schedule IV hereto shall have a right
upon  written  notice  (the  "Conversion  Notice")  to  Parent  on behalf of all
Existing Investors in such Investor Group Designee's Investor Group delivered on
or before June 30,  2003,  to require  (and upon  receipt of such notice  Parent
shall cause and do all things necessary  (including  preparing and filing within
15 days after  receipt of such notice all  required  documents  and  filings) to
obtain all third-party or government  consents,  approvals and authorizations as
may be necessary or advisable to), as promptly as  practicable  (but in no event
later than the latest of (i) the  expiration or  termination  of any  applicable
waiting period under the HSR Act, (ii) the receipt of all necessary  third party
or governmental  consents,  authorizations  or approvals and (iii) 15 days after
receipt of such notice) either,  at the option of each Existing Investor in such
Investor Group, (x) cause a Delaware direct wholly-owned corporate subsidiary of
Parent to merge, in a reorganization intended to be tax-free, into such Existing
Investor  pursuant  to a merger  agreement  substantially  in the form  attached
hereto as  Exhibit I (each,  a "Parent  Merger");  provided  that such  Existing
Investor shall be a corporation permitted under applicable law and its governing
instruments  to  effectuate  a Parent  Merger  and shall  have  represented  and
warranted that such Existing  Investor has no assets or  liabilities  other than
the  Investor  Interests  held by it and its rights and  obligations  under this
Agreement and the Ancillary  Agreements or (y) exchange  shares of common stock,
par value  US$0.01 per share,  of Parent  ("Parent  Common Stock) for all of the
Investor Interests held by such Existing Investor (each, a "Parent Exchange" and
together  with the Parent  Mergers,  the "Parent  Conversions").  In each Parent
Merger,  all of the capital  stock of the Existing  Investor  shall be converted
into shares of Parent Common  Stock,  and in each Parent  Exchange,  the Limited
Partnership  Interests  held by the Existing  Investor  shall be  exchanged  for
Parent  Common  Stock,  in each case with the number of shares of Parent  Common
Stock to be issued to be determined by dividing the Original  Purchase Price (as
defined  below) for the interest in Newco LP held by such Existing  Investor (A)
by US$12,  if the Closing  Price as of the date of  delivery  of the  Conversion
Notice  (the  "Notice  Closing  Price")  is less than or equal to US$24,  (B) by
US$20,  if the Notice Closing Price is greater than or equal to US$40, or (C) if
the Notice Closing Price is greater than US$24 and less than US$40, then by such
number equal to one-half of the Notice Closing Price, as the case may be. In the
event Parent is excused from registering  shares of Parent Common Stock on Forms
S-4 as  contemplated  by  Section 3 of the  Registration  Rights  Agreement,  an
Investor may delay the closing of the Parent  Conversion until such registration
is available or revoke its election  with respect to the Parent  Conversion,  in
which  case such  election  shall be deemed not to have been  exercised  for any
purpose  hereunder.  For purposes of the foregoing,  the term "Original Purchase
Price"  shall mean the sum of (x) the amount paid in June 2000 by such  Existing
Investor for its  interests in Newco LLC (i.e.,  an aggregate of $50 million for
all  Existing  Investors)  and (y) the  amount,  if  any,  paid by the  Existing
Investor at the Second Closing for its additional Limited Partnership  Interests
in Newco LP (i.e., an aggregate of $5 million for all Existing  Investors).  The
number of Units as to which this Section 3.1 applies is 4,487,805.

     (b) For purposes of this  Agreement,  "Closing  Price" means as of any date
and subject to adjustment in the event of a stock split,  stock dividend,  stock
combination or other  recapitalization  of Parent (i) if shares of Parent Common
Stock are listed on a national securities  exchange,  the average of the closing
sale prices per share therefor on the largest securities  exchange on which such
shares are traded on the last twenty (20) trading days before such date, (ii) if
such  shares are listed on The Nasdaq  National  Market but not on any  national
securities  exchange,  the average of the closing bid and asked prices per share
therefor on The Nasdaq  National  Market on the last twenty  (20)  trading  days
before  such date,  or (iii) if such  shares are not listed on either a national
securities  exchange or The Nasdaq National  Market,  the average of the closing
bid and asked  prices per share  therefor in the over the counter  market on the
last thirty (30) trading days before such date.

     (c) If there  shall be any  consolidation  or merger  to which  Parent is a
party,  or any sale or  conveyance  of the  property of Parent as an entirety or
substantially  as an  entirety  (any such event being  called a "Parent  Capital
Reorganization"), then, effective upon the effective date of such Parent Capital
Reorganization,  the Existing  Investors  shall have the right to receive in the
Parent  Conversion  the kind and amount of shares of stock and other  securities
and  property  (including  cash) which the  Existing  Investors  would have been
entitled to receive in connection with such Parent Capital Reorganization if the
Parent  Conversion  had been effected  immediately  prior to such Parent Capital
Reorganization.  As a condition to effecting any Parent Capital  Reorganization,
Parent or the  successor  or  surviving  corporation,  as the case may be, shall
execute and deliver to each  Existing  Investor an agreement as to such Existing
Investor's rights in accordance with this Section 3.1(c). The provisions of this
Section   3.1(c)   shall   similarly   apply  to   successive   Parent   Capital
Reorganizations.

3.2. Staged  Exercise.  To the extent the exercise by the Existing  Investors of
their  rights under  Section 3.1 would  require  prior  approval by the FCC, the
Existing  Investors  and Parent shall enter into such  arrangements  as shall be
reasonably  satisfactory  to the  Existing  Investors  and  Parent to avoid such
result, until the FCC will have had a reasonable time to approve such a request,
including without  limitation,  if the Existing Investors shall so elect, either
(x) Parent  giving the Existing  Investors or their  designees the power to vote
some or all of the  limited  partnership  interests  acquired  by  Parent in the
Parent Conversion(s) until such time as the FCC grants any necessary transfer of
control  application,  or (y) the Existing  Investors  transferring a portion of
their Units to other entities prior to effecting the Parent Conversion(s), which
other entities  would have the right to effect a Parent  Conversion at such time
as the FCC grants any necessary transfer of control application.

SECTION 4.        Representations and Warranties of Parent and Newco.
- --------------------------------------------------------------------

     Except as  disclosed  in the  disclosure  schedule  delivered by Parent and
Newco and incorporated  herein (which shall be updated on the First Closing Date
to reflect  events  occurring in the ordinary  course of business since the date
hereof)  (the  "Parent/Newco  Disclosure  Schedule"),  Parent  and Newco  hereby
represent  and warrant (x) jointly and  severally to the Investors and (y) as to
itself (and in the case of Parent, as to Parent Sub and Sub) to TMI, as follows:

4.1. Organization and Good Standing; Power and Authority;  Qualifications.  Each
of Parent, Parent Sub and Newco LLC (a) is duly organized,  validly existing and
in good standing under the laws of its  jurisdiction of organization and (b) has
all requisite corporate or limited liability company power and authority to own,
lease and  operate its  properties  and to carry on its  business  as  presently
conducted.  Each of Parent, Parent Sub and Newco LLC has all requisite power and
authority  to enter  into and carry out the  transactions  contemplated  by this
Agreement and the Ancillary Agreements to which it is a party.

4.2. Authorization of the Documents. The execution,  delivery and performance by
Parent,  Parent Sub and Newco LLC of this  Agreement  and each of the  Ancillary
Agreements  to which it is a party,  and the  consummation  of the  transactions
contemplated  hereby and  thereby  have been duly  authorized  by all  requisite
action on the part of Parent, Parent Sub and Newco LLC, respectively (and do not
or will not require the approval or consent of the shareholders of Parent),  and
this  Agreement  and  each  of  the  Ancillary  Agreements  when  executed  will
constitute a legal, valid and binding  obligation of each of Parent,  Parent Sub
and Newco LLC, enforceable against Parent and Parent Sub and Newco in accordance
with its terms  except to the  extent  that  enforceability  may be  limited  by
bankruptcy,  insolvency  or  other  similar  laws  affecting  creditors'  rights
generally and except to the extent that the remedy of specific  performance  and
injunction  and other  forms of  equitable  relief may be  subject to  equitable
defenses.  As of the First Closing, the Cross Licensing  Agreement,  as amended,
will have been duly authorized, executed and delivered by Motient Communications
and will be the legal, valid and binding  obligation of Motient  Communications,
enforceable  against it in  accordance  with its terms except to the extent that
enforceability  may be limited by  bankruptcy,  insolvency or other similar laws
affecting  creditors'  rights generally and except to the extent that the remedy
of specific  performance and injunction and other forms of equitable  relief may
be subject to equitable defenses.

4.3.     Capitalization.
- -----------------------

     (a) Parent.  The authorized  capitalization of Parent as of the date hereof
consists of: (i) 200,000 shares of preferred stock, par value US$0.01 per share,
none of which are issued and outstanding,  and (ii) 150,000,000 shares of Parent
Common  Stock,  of which  50,055,190  shares were issued and  outstanding  as of
September  28, 2001.  Since  September  28, 2001,  no shares of capital stock of
Parent have been issued except  pursuant to the exercise of options  outstanding
on September 28, 2001.  All such  outstanding  shares of Parent Common Stock are
validly issued,  fully paid and nonassessable.  The information set forth on the
capitalization table set forth in Section 4.3(a) of the Parent/Newco  Disclosure
Schedule,   including,   without  limitation,   the  information  regarding  the
outstanding  options to purchase  Parent  Common Stock and fully  diluted  share
information  is true,  correct and  complete as September  28,  2001.  Except as
listed in Section 4.3(a) of the Parent/Newco  Disclosure Schedule,  there are no
outstanding options, warrants,  subscription rights, calls or commitments of any
character  whatsoever  relating to, or  securities or rights  convertible  into,
shares of any class of capital stock of Parent, or by which Parent or any of its
subsidiaries  is or may become bound to issue  additional  shares of its capital
stock or options,  warrants or other rights to purchase or acquire any shares of
its capital stock or other rights,  agreements or commitments which obligate the
Parent to register any shares of its capital stock.

     (b) Newco.  The  members of Newco LLC are as  reflected  on Schedule I. All
such  outstanding  interests  in Newco LP will be  validly  issued  at the First
Closing.  Except pursuant to the Newco LP Agreement, no partner of Newco LP will
be  entitled  to  pre-emptive  rights.  There are not now and will not as of the
First Closing be, any outstanding options, warrants,  subscription rights, calls
or commitments of any character  whatsoever  relating to, or interests or rights
convertible into, or exchangeable  for,  interests of any character of Newco LP,
or by which Newco LP is or may become bound to issue additional interests. Newco
LLC has not,  since its  inception,  declared  or paid any  dividend or made any
other distribution of cash or other property to its members.

4.4. Authorization and Issuance of Interests. The authorization,  issuance, sale
and delivery of the TMI Interest, the Investor Interests,  the Convertible Notes
and the Interests  which may be issued upon the  conversion  of the  Convertible
Notes  (the  "Conversion   Interests")   pursuant  to  this  Agreement  and  the
authorization,  reservation,  issuance, sale and delivery of Parent Common Stock
pursuant to the Parent  Conversions  have been duly  authorized by all requisite
action on the part of Newco LLC and Parent, as the case may be, and when issued,
sold and delivered in accordance with this Agreement,  (i) the TMI Interest, the
Investor  Interests  and the  Conversion  Interests  will be validly  issued and
outstanding with no personal liability attaching to the ownership thereof (other
than as provided in the DRULPA) and (ii) the Parent Common Stock will be validly
issued and outstanding,  fully paid and nonassessable with no personal liability
attaching  to  ownership   thereof,   in  each  case,  free  and  clear  of  any
Encumbrances,  other than  Encumbrances,  if any, arising as a result of actions
taken by TMI Sub or the Investors or arising pursuant to applicable  federal and
state  securities  laws,  and not  subject to  preemptive  or similar  rights of
partners or stockholders of Newco LP, Parent or others. The terms, designations,
powers,  preferences and relative,  optional and other special  rights,  and the
qualifications,  limitations and restrictions, of the TMI Interest, the Investor
Interests and the Conversion  Interests are as stated in the Newco LP Agreement.
Parent has  reserved a  sufficient  number of shares of Parent  Common Stock for
issuance in the event of the Parent Conversions.

4.5.     SEC and Other Documents; Financial Statements.
- ------------------------------------------------------

     (a)  Parent  has  delivered  or  made   available  to  the  Investors  each
registration statement, report, proxy statement or information statement and all
exhibits,  amendments  and  supplements  thereto filed with the  Securities  and
Exchange  Commission  ("SEC") since January 1, 2001, which are listed in Section
4.5(a) of the  Parent/Newco  Disclosure  Schedule,  each in the form  (including
exhibits  and  any  amendments  and  supplements  thereto)  filed  with  the SEC
(collectively,  including any such reports filed  subsequent to the date hereof,
the "Parent Reports"). Except as set forth in Section 4.5(a) of the Parent/Newco
Disclosure  Schedule,  the  Parent  Reports  were filed with the SEC in a timely
manner and constitute all forms,  reports and documents  required to be filed by
Parent under the Securities Act of 1933, as amended (the "Securities  Act"), the
Securities  Exchange Act of 1934, as amended (the "Exchange  Act") and the rules
and regulations  promulgated  thereunder (the  "Securities  Laws").  As of their
respective dates, the Parent Reports (i) complied,  and any Parent Reports filed
with  the SEC  subsequent  to the date  hereof  will  comply,  as to form in all
material  respects with the applicable  requirements  of the Securities Laws and
(ii) did not, and any Parent  Reports filed with the SEC  subsequent to the date
hereof will not,  contain  any untrue  statement  of a material  fact or omit to
state a material  fact  required to be stated  therein or  necessary to make the
statements made therein, in the light of the circumstances under which they were
made,  not  misleading.  There  is  no  unresolved  violation  asserted  by  any
government authority with respect to any of the Parent Reports.

     (b) Each of the balance  sheets  included in or  incorporated  by reference
into the Parent  Reports  (including  the related  notes and  schedules)  fairly
presented the  financial  position of the entity or entities to which it relates
as of its date and each of the  statements of operations,  stockholders'  equity
(deficit)  and cash flows  included in or  incorporated  by  reference  into the
Parent Reports  (including any related notes and schedules) fairly presented the
results of operations,  retained  earnings or cash flows, as the case may be, of
the entity or entities to which it relates for the periods set forth therein, in
each case in  accordance  with GAAP  consistently  applied  during  the  periods
involved,  except  as may be  noted  therein  and  except,  in the  case  of the
unaudited  statements,  for the absence of notes thereto,  and subject to normal
recurring  year-end  adjustments which have not been and will not be material in
nature or amount.

4.6. No Undisclosed Liabilities. Except as disclosed in the Parent Reports filed
prior to the date  hereof,  and  except  for  normal  or  recurring  liabilities
incurred since June 30, 2001 in the ordinary course of business  consistent with
past practices, Parent and its subsidiaries do not have any liabilities,  either
accrued,  contingent  or  otherwise,  of the type  required to be  reflected  in
financial  statements in accordance with GAAP, and whether due or to become due,
which  individually  or in the aggregate,  have had or are reasonably  likely to
have a Material Adverse Effect on Parent.

4.7.  Absence of Certain  Changes or Events.  Except as  disclosed in the Parent
Reports  filed with the SEC prior to the date  hereof or in  Section  4.7 of the
Parent/Newco  Disclosure  Schedule,  since  December  31,  2000,  Parent and its
subsidiaries  have conducted  their  respective  businesses only in the ordinary
course, and there has not been (a) any change,  circumstance or event that could
reasonably be expected to result in a Material Adverse Effect on Parent,  Parent
Sub,  Newco,  Sub or the  transactions  contemplated  by this  Agreement  or the
Ancillary  Agreements,  (b) any  declaration,  setting  aside or  payment of any
dividend  or other  distribution  with  respect  to the Parent  Common  Stock or
Investor  Interests,  (c)  any  material  commitment,   contractual  obligation,
borrowing,  capital  expenditure or transaction  (each, a "Commitment")  entered
into by  Parent  or any of its  subsidiaries  outside  the  ordinary  course  of
business,  or (d) any  material  change in the Parent's  accounting  principles,
practices or methods.

4.8. No Conflict.  The execution and delivery by each of Parent and Newco LLC of
this  Agreement,  and by Parent,  Newco LLC, Newco LP, Newco GP, Sub, Parent Sub
and Motient Communications of the Ancillary Agreements to which it is or will be
a party, and the  consummation by each of them of the transactions  contemplated
hereby and  thereby  and  compliance  with the  provisions  hereof  and  thereof
(including,  without limitation, the issuance, sale and delivery of the Investor
Interests,  the  Convertible  Notes and the Conversion  Interests)  will not (a)
violate or conflict  with,  or require any consent,  approval,  notice or filing
under, any provision of any domestic  (federal,  state or local) or foreign law,
statute, rule or regulation, or any ruling, writ, injunction, order, judgment or
decree of any court, administrative agency or other governmental body applicable
to it, or any of its  properties  or assets other than  violations  or conflicts
which would not  reasonably  be expected  to have a Material  Adverse  Effect on
Parent, Newco LLC, Newco LP, Sub, Parent Sub or the transactions contemplated by
this Agreement or the Ancillary Agreements,  (b) conflict with, or result in any
violation  or breach of, or  constitute  (with due  notice or lapse of time,  or
both) a default or loss of a benefit under, or cause or permit the  acceleration
under,  the terms,  conditions or provisions of (i) the Series A and Series B 12
1/4% Senior Notes due 2008 Indenture,  dated March 31, 1998, of Motient Holdings
Inc.  ("Holdings")  (the  "Indenture")  or (ii) any other  indenture,  mortgage,
guaranty, lease, license or other contract, agreement or understanding,  written
or oral (each, a "Contract") to which Parent, Newco LLC, Newco LP, Sub or Parent
Sub is a party or to which any of their properties or assets are subject (all of
which  are  listed  in  Section  4.8 of the  Disclosure  Schedule)  which  could
reasonably be expected to have a Material  Adverse Effect on Parent,  Newco LLC,
Newco LP, Sub or Parent Sub or the transactions  contemplated by this Agreement,
or any of the Ancillary Agreements,  (c) result in the creation or imposition of
any Encumbrance upon any of Parent's,  Newco LLC's,  Newco LP's, Sub's or Parent
Sub's properties or assets which could reasonably be expected to have a Material
Adverse  Effect  on  Parent,  Newco  LLC,  Newco  LP,  Sub,  Parent  Sub  or the
transactions  contemplated by this Agreement or any of the Ancillary Agreements,
or (d)  violate  Parent's,  Newco  LLC's,  Newco  LP's,  Sub's or  Parent  Sub's
organizational documents. Parent, Sub and Parent Sub have received all necessary
consents  or waivers  from their  lenders  and  guarantors  with  respect to the
transactions  contemplated  hereby  and by the  Ancillary  Agreements,  and  the
fairness  opinion(s)  required by Section 4.11 of the  Indenture  has/have  been
obtained and copies of such  documents  have been delivered to the Investors and
TMI. No other  consent,  waiver,  approval,  document or action is required  for
Parent  and  its  subsidiaries  (including  Sub  and  Parent  Sub) to be in full
compliance  with the  provisions of the agreements  relating to their  financing
arrangements  upon consummation of the transactions  contemplated  hereby and by
the Ancillary Agreements.

4.9. Litigation;  Orders. Except as set forth in the Parent Reports, there is no
civil, criminal or administrative action, suit, claim, notice, hearing, inquiry,
proceeding  or  investigation  at law  or in  equity  by or  before  any  court,
arbitrator or similar panel,  governmental  instrumentality  or other agency now
pending or, to the best knowledge of Parent,  threatened  against  Parent,  Sub,
Parent Sub,  Newco LLC or the assets  (including the  Intellectual  Property) of
Parent,  Sub,  Parent Sub,  or Newco LLC (a  "Litigation")  which if  determined
adversely to Parent,  Sub, Parent Sub, or Newco could  reasonably be expected to
have a  Material  Adverse  Effect  on  Parent,  Sub,  Parent  Sub,  Newco or the
transactions contemplated by this Agreement or the Ancillary Agreements. None of
Parent, Sub, Parent Sub, or Newco LLC is subject to any order, writ,  injunction
or decree of any court of any federal,  state,  municipal  or other  domestic or
foreign  governmental   department,   commission,   board,  bureau,   agency  or
instrumentality.

4.10.  Compliance with Laws; Permits.  Except as provided in Section 4.10 of the
Parent/Newco  Disclosure  Schedule  and except for  matters  governed by Section
4.15,  Parent,  Parent  Sub,  Newco LLC and Sub are and have been,  since  their
respective dates of  organization,  in compliance with, and have conducted their
business in compliance with, all federal,  state, local and foreign laws, rules,
ordinances,  codes,  consents,   authorizations,   registrations,   regulations,
decrees, directives,  judgments and orders, including environmental,  applicable
to them other than  instances of  non-compliance  which have not had and are not
reasonably  expected to have a Material  Adverse  Effect on Parent,  Parent Sub,
Newco,  Sub  or  the  transactions  contemplated  hereby  or  by  the  Ancillary
Agreements.  Each of  Parent,  Parent  Sub,  Newco LLC and Sub has all  federal,
state,  local and foreign  governmental  licenses,  permits,  qualifications and
authorizations  ("Permits")  materially necessary in the conduct of its business
as currently  conducted.  All such Permits are in full force and effect,  and no
material  violations  have occurred in respect of any such Permits;  no material
proceeding is pending or, to the best knowledge of Parent,  threatened to revoke
or limit any such  Permit;  and no such Permit will be  suspended,  cancelled or
adversely  modified in any  material  respect as a result of the  execution  and
delivery of this Agreement or the Ancillary  Agreements and the  consummation of
the transactions contemplated hereby or thereby.

4.11.  Offering  Exemption.  Assuming  the accuracy of the  representations  and
warranties  contained  in Section 5 and Section 6 hereof,  the offer and sale of
the  TMI  Interest,  the  Investor  Interests,  the  Convertible  Notes  and the
Conversion Interests as contemplated hereby, and issuance and delivery of Parent
Common  Stock in  connection  with the Parent  Conversions  are each exempt from
registration under the Securities Act as in effect on the date of this Agreement
and under  applicable  state  securities  and "blue sky" laws,  as  currently in
effect.

4.12. Consents. No permit,  authorization,  consent or approval of or by, or any
notification of or filing with, any person (governmental or private) is required
by Parent or Newco in connection with the execution, delivery and performance of
this  Agreement,  or by Parent,  Newco or Sub in connection  with the execution,
delivery and performance of the Ancillary Agreements to which it is a party, the
consummation  by  Parent,   Newco,   Parent  Sub  or  Sub  of  the  transactions
contemplated  by  Section  1  hereof  or by  the  Ancillary  Agreements,  or the
issuance,  sale or delivery of the TMI  Interest,  the  Convertible  Notes,  the
Conversion Interests,  the Investor Interests or Parent Common Stock (other than
(i) such notifications or filings required under the HSR Act, the Communications
Act of 1934,  as  amended  (the  "FCC  Act")  and  applicable  federal  or state
securities laws, if any, which shall be made on a timely basis and (ii) permits,
authorizations,  consents  and  approvals  which,  if not  obtained,  could  not
reasonably be expected to have a Material Adverse Effect on Parent,  Newco, Sub,
Parent Sub or the transactions  contemplated by this Agreement and the Ancillary
Agreements).

4.13. Brokers. No agent,  broker,  investment banker or other firm or person, is
or will be entitled to any broker's or finder's fee or any other  commission  or
similar  fee from  Parent,  Sub,  Parent  Sub or Newco in  connection  with this
Agreement or the Ancillary  Agreements or any of the  transactions  contemplated
hereby or thereby.

4.14.  Public Utility Holding Company,  Etc. Neither Parent or Newco LLC nor any
Subsidiary  is: (i) a "public  utility  company" or a "holding  company,"  or an
"affiliate" or a "subsidiary  company" of a "holding company," or an "affiliate"
of a "public utility company," a "holding company" or a "subsidiary  company" of
a holding  company as such  terms are  defined  in the  Public  Utility  Holding
Company Act of 1935, as amended,  or (ii) a "public  utility," as defined in the
Federal  Power  Act,  as  amended,  or  (iii)  an  "investment  company"  or  an
"affiliated  person" thereof or an "affiliated  person" of any such  "affiliated
person," as such terms are  defined in the  Investment  Company Act of 1940,  as
amended.

4.15.    FCC.
- ------------

     (a) Section 4.15 of the Parent/Newco  Disclosure  Schedule  contains a true
and  complete  list  of  all  material  licenses,  permits,  and  authorizations
("Licenses"),  including  the  frequencies  authorized  for and the issuance and
expiration  dates of each  such  License,  issued to Parent or Sub by the FCC in
connection  with the operation of the Existing Sub Business.  No such License is
subject to any  restriction  or  condition  which  would  limit in any  material
respect the full operation of the Existing Sub Business as now operated,  and no
proceeding, inquiry, investigation or other administrative action is pending or,
to Parent's knowledge,  threatened by or before the FCC that would reasonably be
expected  to result in the  revocation  of any  material  FCC  authorization  or
otherwise  impair in any material respect the full operation of the Existing Sub
Business. The representations  contained in this Section 4.15 are limited by the
statements  set forth in the  section  of  Parent's  most  recent  SEC Form 10-K
entitled  "Business  --  Regulation"  filed  with the  Securities  and  Exchange
Commission on April 2, 2001 ("Regulatory Disclosure").  The statements contained
in the Regulatory Disclosure fully and accurately describe,  with respect to the
Existing Sub Business,  the material legal matters and proceedings arising under
the  Communications   Act  of  1934,  as  amended,   and  the  published  rules,
regulations, and policies promulgated thereunder by the FCC.

     (b) Section 4.15 of the Parent/Newco  Disclosure  Schedule  contains a true
and complete list of all material pending  applications,  including requests for
extension of construction or other performance milestones ("Applications"),  and
including  the  frequencies  applied  for and  the  filing  date  of  each  such
Application,  that have been filed by Parent or Sub with the FCC relating to the
Existing  Sub  Business.  Neither  Parent nor Sub is aware of any reason why any
Application  would not  granted  by the FCC.  Parent and Sub have  delivered  to
Investor true and complete  copies of the Licenses and  Applications,  including
any all additions, amendments and other modifications thereto.

     (c) Sub is the  authorized  legal holder of all the Licenses.  The Licenses
are in good  standing,  are in full force and effect,  and are unimpaired by any
act or  omission  of  Parent,  Sub,  or any of  their  officers,  directors,  or
employees;  and the operation of the Existing Sub Business is in full compliance
with the Licenses.  These  Licenses are sufficient for the lawful conduct of the
business  and  operation  of the  Existing Sub Business in the manner and to the
full extent they are  currently  conducted.  All material  reports,  forms,  and
statements  required to be filed with the FCC with  respect to the  Existing Sub
Business have been filed and are complete and accurate in all material respects.

     (d) In 1999,  Sub had access to the  spectrum  assigned  to Sub in the 1999
coordination  agreement  among  the  North  American  L-band  operators.  Parent
believes  that Sub  should  continue  to have  access in 2001 to as much of this
spectrum as Sub is able to use.

4.16. Sub  Representations  and Warranties.  All  representations and warranties
made by Sub in or pursuant to the Amended and Restated Sub Asset Sale  Agreement
(as qualified by the disclosure  schedule thereto),  are incorporated  herein as
though made in their entirety by Parent in this Agreement.

4.17.  Restrictions.  As of the First Closing, Newco shall not be a party to, or
subject to, any loan agreement or other  financing  document  giving rise to any
obligations,  restrictions, limitations or Encumbrances with respect to Newco or
its assets,  other than the TMI Note,  the MSI Note and the  Convertible  Notes.
Following  consummation  of the First Closing the  requirements of Parent's Loan
Agreements relating to Parent's subsidiaries shall cease to be applicable, other
than  Parent's  pledge  of all of its  interest  in  Newco LP to its  banks  and
guarantors.  4.18.  Newco LLC  Activities.  The Newco  Financial  Statements (as
defined in the June Investment  Agreement) comply with provisions of Section 7.8
of the June Investment Agreement.  Since inception, Newco LLC has not engaged in
any activity  requiring the consent of the Existing Investors under the terms of
the June  Agreements  other than  activities  for which such  consents have been
obtained.

4.19. Accredited Investor. Parent Sub is an "Accredited Investor" (as defined in
Rule 501(a) under the Securities Act).

4.20.  Disclosure.  Neither this Agreement nor any Ancillary  Agreement (nor any
certificate  or  instrument  executed in connection  with this  Agreement or any
Ancillary  Agreement)  furnished or made to TMI or the Investors by or on behalf
of Parent,  Parent Sub, Sub or Newco omits to state a material  fact required to
be  stated  herein  or  therein  or  necessary  in order to make the  statements
contained herein or therein, in light of the circumstances under which they were
made, not misleading.

4.21.  Newco  Financial  Statements.  Each of the balance sheets included in the
Newco Financial  Statements fairly presented the financial  position of Newco as
of the date thereof and the statements of operations,  members' capital and cash
flows  included  therein fairly  presented the results of  operations,  members'
capital or cash flows,  as the case may be, for the period set forth,  or ended,
therein,  in each case in accordance with GAAP  consistently  applied during the
period involved,  except as may be noted therein and subject to normal recurring
year end adjustments which have not been, and will not be, material in nature or
amount.

4.22. No Undisclosed  Liabilities  of Newco.  Except as disclosed in the balance
sheet dated August 31, 2001, included in the Newco Financial Statements,  copies
of which  have been  provided  to TMI and the  Investors,  and except for normal
recurring  liabilities  incurred  since  such  date in the  ordinary  course  of
business  consistent with past practices,  Newco does not have any  liabilities,
either accrued, contingent or otherwise, of the type required to be reflected in
financial  statements in accordance with GAAP or which, whether due or to become
due,  individually  or in the aggregate,  have had or are  reasonably  likely to
have, a Material Adverse Effect on Newco.

4.23.  Absence of Certain  Changes and Events.  Except as disclosed in the Newco
Financial Statements,  since the date thereof,  Newco has conducted its business
only in the ordinary course and there has not been (a) any change,  circumstance
or event that  could  reasonably  be  expected  to result in a Material  Adverse
Effect  on  Newco,  (b)  any  declaration   setting  aside  or  payment  of  any
distribution to any member thereof, (c) any material Commitment (other than this
Agreement and agreements and  instruments  contemplated  hereby) entered into by
Newco  outside the ordinary  course of business,  or (d) any material  change in
Newco's accounting principles or methods.

4.24.  Title.  Newco  has  good  and  marketable  title  to all of its  material
properties and assets,  real and personal,  owned,  leased or licensed,  in each
case subject only to Encumbrances created in the ordinary course of business.

4.25.    No Other Agreements.

     There are no other  agreements to which any of Parent,  Parent Sub or Newco
is a party related to or connected with the  transactions  contemplated  hereby,
except for the Ancillary Agreements.

SECTION 5.        Representations and Warranties of the Investors.
- -----------------------------------------------------------------

     Each  Investor  represents  and  warrants  to the other  parties  hereto as
follows:

5.1.     Investment Representations.
- -----------------------------------

     (a) In the  case of each  Second  Closing  Investor,  such  Second  Closing
Investor understands that the limited partner interests in Newco LP to be issued
pursuant  hereto (the  "Additional  Interests") and the Parent Common Stock that
may be issued pursuant to the Parent Conversion (the "Parent Securities"), or in
the case of a Note Investor,  the Convertible Notes and the Conversion Interests
that may be issued pursuant to the Convertible Notes (the "Note Securities") (i)
have not been, and will not be, registered under the Securities Act or any state
securities  laws,  (ii) are being offered and sold pursuant to an exemption from
registration   contained   in  the   Securities   Act   based  in  part  on  the
representations  of such  Investor  contained in this  Agreement,  and (iii) the
Investor  Interests,  the Parent  Securities and the Note  Securities may not be
sold  unless  such  disposition  is  registered  under  the  Securities  Act and
applicable state securities laws or is exempt from registration thereunder.

     (b) Acquisition for Own Account.  Such Investor will acquire the Additional
Interests, Parent Securities and/or the Note Securities, as the case may be, for
its own account,  for  investment  only and not with a view to the  distribution
thereof within the meaning of the Securities Act.

     (c)  Accredited  Investor;   Domicile.  Such  Investor  is  an  "Accredited
Investor" (as defined in Rule 501(a) under the Securities Act). Such Investor is
a resident of the State or  Commonwealth  set forth next to such Investor's name
on Schedule III or IV hereto,  as the case may be, and the  Investor  Interests,
the Parent  Securities  and/or  the Note  Securities,  as the case may be,  were
offered and sold to such Investor solely in the State or Commonwealth  set forth
next to such Investor's name on Schedule III or IV hereto.

     (d) Investors  Able to Bear Economic  Risk.  Such Investor has  substantial
experience in evaluating and investing in private  transactions of securities in
companies  similar to Newco and Parent so that it is capable of  evaluating  the
merits and risks of its  investment  in Newco and Parent and has the capacity to
protect its own interests.  Such Investor  understands that an investment in the
Additional Interests,  the Parent Securities and/or the Note Securities,  as the
case may be,  acquired  pursuant to this  Agreement  is highly  speculative  and
involves  substantial economic risk. Such Investor understands that it must bear
the  economic  risk  of  this  investment  indefinitely  unless  the  Additional
Interests,  the Parent  Securities and/or the Note Securities that such Investor
purchases are registered  pursuant to the  Securities  Act, or an exemption from
registration  is  available  for the  resale of such  securities,  and that such
Investor may sustain, and is financially able to sustain, a complete loss of its
investment  pursuant to this Agreement.  Such Investor  understands that neither
Parent  nor  Newco has any  present  intention  of  registering  the  Additional
Interests,  the Parent  Securities  or the Note  Securities.  Such Investor also
understands  that there is no assurance  that any  exemption  from  registration
under the Securities Act for the resale of such securities will be available and
that, even if available,  such exemption may not allow such Investor to transfer
all or any portion of Additional  Interests and/or Parent  Securities and/or the
Note  Securities  under the  circumstances,  in the amounts or at the times such
Investor might propose.

     (e)  Investor  Can  Protect  Its  Interest.  By  reason  of  its  or of its
management's business or financial experience, such Investor has the capacity to
protect its own interests in connection  with the  transactions  contemplated by
this  Agreement.  Further,  such  Investor  is  aware of no  publication  of any
advertisement  in  connection  with  the   transactions   contemplated  by  this
Agreement.

     (f) Newco Information.  Such Investor has had an opportunity to discuss the
business,  management  and financial  affairs of Parent,  Sub and Newco LLC with
directors,  officers and management of Parent,  Sub and Newco LLC. Such Investor
has also had the  opportunity  to ask  questions  of, and receive  answers from,
Parent, Sub and Newco LLC and its management  regarding the terms and conditions
of its  investment.  Such  Investor  is  not  relying  on  any  representations,
warranties  or  information  as to  Newco  other  than the  representations  and
warranties made to it herein or pursuant hereto and in the Ancillary Agreements.

5.2. Organization and Good Standing;  Power and Authority.  Such Investor (i) is
duly  organized,  validly  existing and in good  standing  under the laws of its
jurisdiction  of  organization  and (ii) has all requisite  corporate  power and
authority to own,  lease and operate its properties and to carry on its business
as presently  conducted.  Such Investor has all requisite power and authority to
enter into and carry out the transactions contemplated by this Agreement and the
Ancillary Agreements to which it is a party.

5.3. Authorization of Documents. The execution, delivery and performance by each
Investor of this Agreement and each of the Ancillary Agreements to which it is a
party and the consummation of the transactions  contemplated  hereby and thereby
have been duly authorized by all requisite  corporate action on the part of such
Investor, and this Agreement and each of such Ancillary Agreements when executed
will  constitute  a  legal,  valid  and  binding  obligation  of such  Investor,
enforceable  against such Investor in accordance  with its terms,  except to the
extent that  enforceability  may be limited by  bankruptcy,  insolvency or other
similar laws affecting creditors' rights generally and except to the extent that
the remedy of specific  performance  and injunction and other forms of equitable
relief may be subject to equitable defenses.

5.4. No Conflict.  The execution and delivery by such Investor of this Agreement
and the Ancillary  Agreements to which it is a party,  and the  consummation  by
such Investor of the transactions contemplated hereby and thereby and compliance
with the provisions hereof and thereof will not (a) violate or conflict with, or
require any consent,  approval,  notice or filing  under,  any  provision of any
domestic (federal,  state or local) or foreign law, statute, rule or regulation,
or any  ruling,  writ,  injunction,  order,  judgment  or decree  of any  court,
administrative agency or other governmental body applicable to it, or any of its
properties  or assets,  (b) conflict  with, or result in any violation or breach
of, or constitute  (with due notice or lapse of time, or both) a default or loss
of a benefit  under,  or cause or permit  the  acceleration  under,  the  terms,
conditions or provisions of any indenture, mortgage, guaranty, lease, license or
other  contract,  agreement or  understanding,  written or oral to which it is a
party or to which its properties or assets is subject, which could reasonably be
expected  to have a  Material  Adverse  Effect  on such  Investor's  ability  to
consummate the  transactions  contemplated  by the Agreement,  (c) result in the
creation or imposition of any Encumbrance  upon any of its properties or assets,
which could  reasonably  be expected to have a Material  Adverse  Effect on such
Investor's ability to consummate the transactions contemplated by this Agreement
or (d) violate its organizational documents.

5.5. Litigation;  Orders. There is no civil, criminal or administrative  action,
suit, claim, notice, hearing, inquiry,  proceeding or investigation at law or in
equity by or  before  any  court,  arbitrator  or  similar  panel,  governmental
instrumentality  or other  agency now pending or, to the best  knowledge of such
Investor, threatened against such Investor which if determined adversely to such
Investor could  reasonably be expected to have a Material Adverse Effect on such
Investor's   ability  to  consummate  the  transactions   contemplated  by  this
Agreement. Such Investor is not subject to any order, writ, injunction or decree
of any court of any  federal,  state,  municipal  or other  domestic  or foreign
governmental department, commission, board, bureau, agency or instrumentality.

5.6.  Compliance with Laws;  Permits.  Such Investor is and has been,  since the
date of its incorporation, in compliance with, and has conducted its business in
compliance with, all federal, state, local and foreign laws, rules,  ordinances,
codes,   consents,   authorizations,    registrations,   regulations,   decrees,
directives,  judgments and orders  applicable to it, which if Investor failed to
comply  would be  reasonably  likely to have a Material  Adverse  Effect on such
Investor's ability to consummate the transactions contemplated by this Agreement
and the Ancillary Agreements.

5.7. Consents.  No permit,  authorization,  consent or approval of or by, or any
notification of or filing with, any person (governmental or private) is required
by such Investor in connection  with the execution,  delivery and performance of
this Agreement, or in connection with the execution, delivery and performance of
the Ancillary  Agreements to which it is a party,  or the  consummation  by such
Investor  of the  transactions  contemplated  hereby or thereby  (other than (i)
notifications  or filings required under the HSR Act, the FCC Act and applicable
federal or state  securities  law, if any, which shall be made on a timely basis
and (ii) permits, authorizations, consents and approvals which, if not obtained,
could not  reasonably  be  expected  to have a Material  Adverse  Effect on such
Investor's ability to consummate the transactions contemplated by this Agreement
and the Ancillary Agreements).

5.8. Brokers. No agent, broker, investment banker or other firm or person, is or
will be entitled to any  broker's or  finder's  fee or any other  commission  or
similar fee from such Investor in connection  with this  Agreement or any of the
transactions  contemplated  hereby for which anyone but such  Investor  would be
responsible.

5.9. Financial Resources. In the case of each Note Investor, such Note Investor
shall have sufficient cash available to it on and as of the First Closing Date
to perform its obligations under Sections 1.2(a) and 1.5(c) hereof (including
paying the purchase price for the Convertible Notes specified opposite such Note
Investor's name on Schedule III hereto) and prior to the First Closing Date
shall provide the other parties hereto with any information reasonably requested
by them as to the beneficial ownership and financial resources of such Note
Investor.

SECTION 6.        Representations and Warranties of TMI.
- -------------------------------------------------------

     Except  as  disclosed  in the  disclosure  schedule  delivered  by TMI  and
incorporated herein (which shall be updated on the First Closing Date to reflect
events  occurring in the ordinary course of business since the date hereof) (the
"TMI  Disclosure  Schedule"),  TMI  represents and warrants to the other parties
hereto as follows:

6.1.     Investment Representations.
- -----------------------------------

     (a) TMI  understands  that the TMI Interest (i) has not been,  and will not
be,  registered  under the Securities Act or any state  securities laws, (ii) is
being offered and sold pursuant to an exemption from  registration  contained in
the Securities Act based in part on the representations of TMI contained in this
Agreement, and (iii) may not be sold unless such disposition is registered under
the  Securities  Act and  applicable  state  securities  laws or is exempt  from
registration thereunder.  TMI also understands that the TMI Interest (i) has not
been  qualified for  distribution  to the public in Ontario under the Securities
Act (Ontario),  (ii) is being offered and sold pursuant to an exemption from the
prospectus and registration  requirements of such Act, and (iii) may not be sold
in Canada unless qualified for distribution to the public by registered  dealers
under  applicable  securities  laws in Canada or such sale is made in accordance
with an exemption  from the  prospectus and  registration  requirements  of such
applicable securities law.

     (b) Acquisition for Own Account.  TMI Sub is acquiring the TMI Interest for
its own account,  for  investment  only and not with a view to the  distribution
thereof within the meaning of the Securities Act.

     (c) Accredited Investor;  Domicile. TMI Sub is an "Accredited Investor" (as
defined in Rule 501(a) under the Securities Act). TMI has its executive  offices
in Ontario,  Canada and the TMI  Interest was offered and sold to TMI Sub solely
in New York and Ontario.

     (d) TMI Able to Bear Economic Risk. TMI  understands  that an investment in
the TMI Interest acquired  pursuant to this Agreement is highly  speculative and
involves  substantial  economic  risk.  TMI  understands  that it must  bear the
economic  risk of this  investment  indefinitely  unless  the  TMI  Interest  is
registered  pursuant to the Securities Act, or an exemption from registration is
available,  and that TMI may  sustain,  and is  financially  able to sustain,  a
complete loss of its investment pursuant to this Agreement. TMI understands that
Newco LLC has no present  intention of  registering  the TMI Interest.  TMI also
understands  that there is no assurance  that any  exemption  from  registration
under the  Securities  Act will be available and that,  even if available,  such
exemption  may not allow TMI to transfer  all or any portion of the TMI Interest
under the circumstances, in the amounts or at the times TMI might propose.

     (e) TMI Can Protect Its Interest.  By reason of its or of its  management's
business  or  financial  experience,  TMI has the  capacity  to protect  its own
interests in connection  with the  transactions  contemplated by this Agreement.
Further,  as of  the  date  hereof  TMI  is  aware  of  no  publication  of  any
advertisement  in  connection  with  the   transactions   contemplated  by  this
Agreement.

     (f) Newco Information.  TMI has had an opportunity to discuss the business,
management  and  financial  affairs of Newco LLC with  directors,  officers  and
management  of Parent and Newco  LLC.  TMI has also had the  opportunity  to ask
questions of, and receive answers from,  Parent and Newco LLC and its management
regarding the terms and conditions of this Investment. TMI is not relying on any
representations,   warranties  or   information  as  to  Newco  other  than  the
representations   and  warranties  made  to  it  herein  and  in  the  Ancillary
Agreements.

6.2. Organization and Good Standing; Power and Authority.  Each of TMI, Canadian
Holdco,  Canadian License Co. and ULC (as of the date hereof and as of the First
Closing  Date)  and TMI Sub (as of the  First  Closing  Date  only)  (i) is duly
organized,  validly  existing  and  in  good  standing  under  the  laws  of its
jurisdiction of organization, (ii) has all requisite power and authority to own,
lease and  operate its  properties  and to carry on its  business  as  presently
conducted and as proposed to be conducted, and (iii) has all requisite power and
authority  to enter  into and carry out the  transactions  contemplated  by this
Agreement and the Ancillary  Agreements to which it is (or is to be) a party. As
of the First Closing Date, TMI will be the sole limited  partner of TMI Sub, and
a wholly owned subsidiary of TMI will be the sole general partner of TMI Sub. As
of the date hereof, TMI owns 100% of the issued and outstanding capital stock of
(a)  Canadian  Holdco,  (b)  Canadian  License  Co.  and (c) ULC.  Copies of the
organizational  documents of Canadian Holdco,  Canadian License Co. and ULC have
been delivered to Parent and to each of the Investors.

6.3. Authorization of Documents. The execution, delivery and performance by TMI,
Canadian  Holdco,  Canadian License Co. and ULC (as of the date hereof and as of
the First  Closing  Date) and by TMI Sub (as of the First  Closing Date only) of
this  Agreement and each of the Ancillary  Agreements to which it is a party and
the consummation of the transactions  contemplated  hereby and thereby have been
duly authorized by all requisite  corporate action on the part of such entities,
and this  Agreement  and each of such  Ancillary  Agreements  when executed will
constitute a legal, valid and binding  obligation of such entities,  enforceable
against  them  in  accordance  with  its  terms,   except  to  the  extent  that
enforceability  may be limited by  bankruptcy,  insolvency or other similar laws
affecting  creditors'  rights generally and except to the extent that the remedy
of specific  performance and injunction and other forms of equitable  relief may
be subject to equitable defenses.

6.4. No Conflict.  The execution and delivery by each of TMI,  Canadian  Holdco,
Canadian  License Co. and ULC (as of the date hereof and as of the First Closing
Date) and by TMI Sub (as of the First  Closing Date only) of this  Agreement and
the Ancillary  Agreements to which it is a party,  and the  consummation by TMI,
Canadian  Holdco,  Canadian License Co. and ULC (as of the date hereof and as of
the First  Closing  Date) and by TMI Sub (as of the First  Closing Date only) of
the  transactions  contemplated  hereby  and  thereby  and  compliance  with the
provisions  hereof and thereof  will not  (subject to  obtaining  all  necessary
consents  and  approvals  as set out herein and therein) (a) violate or conflict
with, or require any consent, approval, notice or filing under, any provision of
any  domestic  (federal,  state or  local)  or  foreign  law,  statute,  rule or
regulation,  or any ruling, writ,  injunction,  order, judgment or decree of any
court, administrative agency or other governmental body applicable to it, or any
of its properties or assets,  with the exception of the Industry Canada Approval
and the CRTC  Approval,  (b) conflict with, or result in any violation or breach
of, or constitute  (with due notice or lapse of time, or both) a default or loss
of a benefit  under,  or cause or permit  the  acceleration  under,  the  terms,
conditions or provisions of any indenture, mortgage, guaranty, lease, license or
other  contract,  agreement or  understanding,  written or oral to which it is a
party or to which its properties or assets is subject, which could reasonably be
expected  to have a  material  adverse  effect on the  ability of any of them to
consummate  the  transactions  contemplated  by this  Agreement or the Ancillary
Agreements, (c) result in the creation or imposition of any Encumbrance upon any
of their  properties  or assets,  which could  reasonably  be expected to have a
material  adverse  effect  on the  ability  of any of  them  to  consummate  the
transactions  contemplated by this Agreement or the Ancillary  Agreements or (d)
violate the organizational documents of any of them.

6.5. Litigation;  Orders. There is no civil, criminal or administrative  action,
suit, claim, notice, hearing, inquiry,  proceeding or investigation at law or in
equity by or  before  any  court,  arbitrator  or  similar  panel,  governmental
instrumentality  or other  agency now pending or, to the best  knowledge of TMI,
threatened  which could reasonably be expected to have a material adverse effect
on the ability of TMI, TMI Sub, Canadian Holdco,  Canadian License Co. or ULC to
consummate  the  transactions   contemplated  by  this  Agreement  or  Ancillary
Agreements. None of TMI, Canadian Holdco, Canadian License Co. or ULC (as of the
date  hereof  and as of the  First  Closing  Date)  or TMI Sub (as of the  First
Closing Date only) is subject to any material order, writ,  injunction or decree
of any court of any  federal,  state,  municipal  or other  domestic  or foreign
governmental  department,  commission,  board, bureau, agency or instrumentality
which could  reasonably be expected to have a Material  Adverse Effect on any of
such entities or a material  adverse  effect on TMI's ability to consummate  the
transactions contemplated by this Agreement.

6.6.  Compliance with Laws;  Permits.  Each of TMI,  Canadian  Holdco,  Canadian
License Co. and ULC (as of the date hereof and as of the First Closing Date) and
by TMI Sub (as of the First  Closing Date only) is and has been,  since the date
of its  organization,  in  compliance  with,  and has  conducted its business in
compliance with, all federal, state, local and foreign laws, rules,  ordinances,
codes,   consents,   authorizations,    registrations,   regulations,   decrees,
directives,  judgments  and orders  applicable  to it,  other than  instances of
non-compliance  which would not have a Material Adverse Effect on its ability to
consummate  the  transactions  contemplated  by this Agreement and the Ancillary
Agreements.  With the exception of the Industry Canada Application Order and the
CRTC Approval,  each of TMI, Canadian Holdco,  Canadian License Co., and ULC (as
of the date hereof and as of the First Closing Date) or TMI Sub (as of the First
Closing  Date only) has all Permits  materially  necessary in the conduct of its
business as currently conducted.  All such Permits are in full force and effect,
and no material  violations  have  occurred in respect of any such  Permits;  no
material  proceeding is pending or, to the best knowledge of TMI,  threatened to
revoke or limit any such Permit; and no such Permit will be suspended, cancelled
or  adversely  modified  as a  result  of the  execution  and  delivery  of this
Agreement or the Ancillary  Agreements and the  consummation of the transactions
contemplated hereby or thereby.

6.7. Consents.  No permit,  authorization,  consent or approval of or by, or any
notification of or filing with, any person (governmental or private) is required
by TMI in  connection  with the  execution,  delivery  and  performance  of this
Agreement, or in connection with the execution,  delivery and performance of the
Ancillary  Agreements to which it is a party, or the  consummation by TMI of the
transactions  contemplated  hereby or thereby (other than (i)  notifications  or
filings  required  under the HSR Act, the FCC Act,  the Canadian  Communications
Statutes and  applicable  federal  (U.S.  or  Canadian)  or state or  provincial
securities  law, if any,  which shall be made on a timely basis,  (ii) contracts
requiring  consent to assign as disclosed in the TMI Asset Sale  Agreements  and
the disclosure schedule(s) thereto, and (iii) permits, authorizations,  consents
and approvals which, if not obtained, could not reasonably be expected to have a
Material  Adverse  Effect  on  TMI's  ability  to  consummate  the  transactions
contemplated by this Agreement and the Ancillary Agreements).

6.8.  Canadian  Holdco  and  Canadian  License  Co.  As of the date  hereof  and
immediately  prior to the First Closing,  (i) Canadian Holdco,  Canadian License
Co.  and  ULC  have  no  assets  or  liabilities   other  than  nominal  capital
contributions  and their respective  rights and obligations  arising pursuant to
the TMI Asset Sale  Agreements,  and (ii) TMI holds 100  percent of the  capital
stock of each of Canadian Holdco, Canadian License Co. and ULC.

6.9.  TMI  Representations  and  Warranties.  All  of  the  representations  and
warranties  made by TMI and  its  affiliates  in or  pursuant  to the  Ancillary
Agreements  are  incorporated  herein as though made in their entirety by TMI in
this Agreement as of the date or dates such  representations  and warranties are
made pursuant to the Ancillary Agreements.

6.10. Solvency. TMI has, and will have as of the First Closing Date, the ability
to pay its debts as they become due.

6.11. Brokers. No agent,  broker,  investment banker or other firm or person, is
or will be entitled to any broker's or finder's fee or any other  commission  or
similar fee acting on behalf of TMI or any of its affiliates in connection  with
this Agreement or any of the transactions contemplated hereby.

6.12.    TMI Licenses.

     (a)  Section  6.12(a) of the TMI  Disclosure  Schedule  contains a true and
complete  list of all  material  licenses,  permits,  and  authorizations  ("TMI
Licenses"),  including  the  frequencies  authorized  for and the  issuance  and
expiration dates of each such License, issued to TMI by the FCC, Industry Canada
and the CRTC in connection  with the operation of the Existing TMI Business.  No
such TMI License is subject to any restriction or condition which would limit in
any  material  respect the full  operation  of the  Existing TMI Business as now
operated,  and no proceeding,  inquiry,  investigation  or other  administrative
action is  pending  or, to TMI's  knowledge,  threatened  by or before  the FCC,
Industry  Canada or the CRTC that would  reasonably be expected to result in the
revocation  of any  material  FCC,  Industry  Canada  or CRTC  authorization  or
otherwise  impair in any material respect the full operation of the Existing TMI
Business.

     (b)  Section  6.12 of the  TMI  Disclosure  Schedule  contains  a true  and
complete  list of all  material  pending  applications,  including  requests for
extension of construction or other performance  milestones ("TMI Applications"),
and including the  frequencies  applied for and the filing date of each such TMI
Application,  that have been filed by TMI with the FCC,  Industry  Canada or the
CRTC  relating  to the  Existing  TMI  Business  and the future  business  to be
conducted by Canadian License Co. and Canadian  Holdco.  TMI is not aware of any
reason why any TMI  Application  relating to the Existing TMI Business would not
be granted by the FCC,  Industry  Canada or the CRTC as the case may be. TMI has
delivered to each Investor true and complete  copies of the TMI Licenses and TMI
Applications,   including   any  and  all   additions,   amendments   and  other
modifications thereto.

     (c) TMI is the  authorized  legal holder of all the TMI  Licenses.  The TMI
Licenses are in good standing,  are in full force and effect, and are unimpaired
by any act or omission of TMI or any of its officers,  directors,  or employees;
and the  operation of the Existing TMI Business is in full  compliance  with the
TMI  Licenses.  The TMI Licenses are  sufficient  for the lawful  conduct of the
business  and  operation  of the  Existing TMI Business in the manner and to the
full extent they are  currently  conducted.  All material  reports,  forms,  and
statements  required to be filed with the FCC, Industry Canada and the CRTC with
respect  to the  Existing  TMI  Business  have been filed and are  complete  and
accurate in all material respects.

     (d) TMI is eligible to operate as a  telecommunications  common  carrier in
Canada, as defined under and in accordance with the Canadian  Telecommunications
Act (the "Telecommunications  Act") and the Canadian  Telecommunications  Common
Carrier Ownership and Control Regulations (the "Ownership Regulations").

     (e) TMI does not violate the prohibition  contained in subsection  16(4) of
the  Telecommunications  Act against operating in Canada as a telecommunications
common carrier when ineligible to do so.

     (f)  Control of TMI is not  exercised  by any  person(s)  that is (are) not
Canadian,  in accordance with the meanings  ascribed to the term "control" under
the   Telecommunications  Act  and  the  term  "Canadian"  under  the  Ownership
Regulations.

     (g) TMI is eligible to hold radio  licences  authorizing  the  operation in
Canada of radio apparatus,  as defined under and in accordance with the Canadian
Radiocommunication   Act  (the   "Radiocommunication   Act")  and  the  Canadian
Radiocommunication Regulations (the "Radio Regulations").

     (h) TMI does not violate the  prohibition  contained in subsection  4(1) of
the  Radiocommunication  Act against  operating radio apparatus in Canada except
under and in accordance with a radio licence issued by Industry Canada.

     (i)  Control of TMI is not  exercised  by any  person(s)  that is (are) not
Canadian,  in accordance with the meanings  ascribed to the terms "Canadian" and
"Canadian-owned and controlled" under the Radio Regulations.

     (j)  Canadians,  as defined under the Ownership  Regulations  and the Radio
Regulations,  beneficially  own,  directly or  indirectly,  in the aggregate and
otherwise than by way of security only, all of the interests in TMI.

6.13.    Other Representations and Warranties.

     (a) Except for the CRTC Approval,  the Industry  Canada  Approval,  the FCC
Change  of  Control   Approval  and  the  FCC  Other   Approvals,   no  consent,
authorization,  approval, order, exemption,  waiver, or other action of the FCC,
Industry Canada or the CRTC is required for the consummation of the transactions
contemplated by this Agreement.

     (b) The business and  operations  conducted and proposed to be conducted by
TMI, TMI Sub, Canadian License Co., and Canadian Holdco are not regulated by any
federal or provincial utility or rate-regulating commission, other than the CRTC
and Industry Canada,  in the areas in which TMI, TMI Sub,  Canadian License Co.,
and Canadian  Holdco conduct or propose to conduct their business and operations
and TMI, TMI Sub,  Canadian  License Co., and Canadian Holdco are not, and based
on existing  regulations  will not be,  required to obtain any License or Permit
from any such  utility or  rate-regulating  commission,  other than the CRTC and
Industry Canada, in any such province.

     (c) To the  best of TMI's  knowledge,  there is no  pending  or  threatened
change in the  Canadian  Communications  Statutes  which  would  have a Material
Adverse  Effect  on the  Existing  TMI  Business,  other  than  recently-imposed
Canadian universal service support mechanisms.

6.14.    First Closing Date Licenses.

     (a) Provided that the CRTC Approval  shall have been granted and shall have
been  issued and become  effective  and that the  Industry  Canada  Transfer  of
License  Approval  shall have been issued and become  effective  as of the First
Closing Date:  Canadian  License Co. will be the authorized  legal holder of all
the Canadian License Co. Licenses, which will be in good standing, in full force
and effect, and unimpaired by any act or omission of Canadian License Co. or any
of their  officers,  directors,  or  employees;  the  operation  of the Canadian
License Co. business will be in full  compliance  with the Canadian  License Co.
Licenses;  the Canadian  License Co.  Licenses will be sufficient for the lawful
conduct of the business and operation of the Canadian License Co. business;  and
all material reports,  forms, and statements  required to be filed with Industry
Canada and the CRTC with respect to the Canadian  License Co. business will have
been filed and will be complete and accurate in all material respects.

     (b) As of the First Closing Date,  Canadian License Co. will be eligible to
hold radio licences  authorizing the operation in Canada of radio apparatus,  as
defined under and in accordance  with the  Radiocommunication  Act and the Radio
Regulations.

     (c) As of the First Closing Date, Canadian License Co. will not violate the
prohibition contained in subsection 4(1) of the  Radiocommunication  Act against
operating  radio apparatus in Canada except under and in accordance with a radio
licence issued by Industry Canada.

     (d) As of the First Closing Date,  Canadian License Co. will be eligible to
operate as a  telecommunications  common carrier in Canada, as defined under and
in accordance with the Telecommunications Act and the Ownership Regulations.

     (e) As of the First Closing Date, Canadian License Co. will not violate the
prohibition contained in subsection 16(4) of the  Telecommunications Act against
operating in Canada as a telecommunications common carrier when ineligible to do
so.

     (f) As of the First Closing Date,  control of Canadian License Co. will not
be exercised by any person(s) that is (are) not Canadian, in accordance with the
meanings ascribed to the term "control" under the Telecommunications Act and the
term "Canadian" under the Ownership Regulations. Control of Canadian License Co.
is not exercised by any person(s) that is (are) not Canadian, in accordance with
the  meanings  ascribed  to  the  terms  "Canadian"  and   "Canadian-owned   and
controlled" under the Radio Regulations.

     (g) As of the First Closing Date, Canadians, as defined under the Ownership
Regulations  and the Radio  Regulations,  will  beneficially  own,  directly  or
indirectly,  in the aggregate and otherwise than by way of security only, 80% of
the voting  equity of Canadian  License Co. and 66 2/3% of the voting  equity of
Canadian Holdco.

     (h) As of the First  Closing  Date,  Canadian  Holdco,  in  respect  of its
ownership  of and control  over  Canadian  License Co will be a carrier  holding
corporation, as defined under the Ownership Regulations.

     (i) As of the First Closing Date, Canadian Holdco will be a carrier holding
corporation  that is a qualified  corporation,  as defined  under the  Ownership
Regulations.

6.15.  Disclosure.  Neither this Agreement nor any Ancillary  Agreement (nor any
certificate  or  instrument  executed in connection  with this  Agreement or any
Ancillary  Agreement)  furnished or made to Parent, Newco or the Investors by or
on behalf of TMI or TMI Sub omits to state a material fact required to be stated
herein or therein or necessary in order to make the statements  contained herein
or  therein,  in light of the  circumstances  under  which they were  made,  not
misleading.

SECTION 7.        Right to Require Valuation.
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     (a) If one or more of the Existing  Investors  shall have  exercised its or
their rights under Section 3.1 (the "Flipper(s)"),  then, beginning on the fifth
anniversary of the Second Closing Date, those Existing Investors who were in the
same  Investors  Group as the Flippers  (the "Flipper  Sisters")  shall have the
right (i) by delivery of a notice (the  "Appraisal  Notice") to Newco LP and the
other  partners in Newco LP, to require  that the Fair Market  Value (as defined
below) of Newco LP be determined  as provided  below and (ii) unless the Limited
Partnership  Interests  then held by such Existing  Investors (but excluding any
Units that were  acquired  after the  Second  Closing  other  than from  another
Existing  Investor  (other than Units acquired by such other  Existing  Investor
after the Second Closing)) are purchased pursuant to clause (d) or (f) below, to
exercise the rights provided in clause (e) below.

     (b) As used herein, the term "Fair Market Value" shall mean the fair market
value of all of the  partnership  interests  of Newco LP,  meaning the best cash
price  obtainable upon an auction of all the partnership  interests in Newco LP,
in the  form  of a sale of such  interests  or a  merger  in  which  all of such
interests  are  converted  into the right to receive cash at the closing of such
merger,  conducted  by a  nationally  recognized  investment  banking  firm with
substantial  experience valuing  telecommunications  businesses,  with the buyer
being an entity which is under no  compulsion to buy and the sellers being under
no compulsion to sell, and with all parties having  reasonable  knowledge of all
relevant  facts.  The  Fair  Market  Value  shall be  determined  by one or more
Appraisers  in  accordance  with clause (c) below or by agreement of the Flipper
Sisters and Newco LP.

     (c) As used herein,  the term  "Appraiser"  shall mean an appraiser  having
experience  valuing  telecommunications  businesses  selected as  follows.  Upon
delivery of the Appraisal Notice, the Flipper Sisters and Newco LP shall attempt
to agree upon a mutually acceptable Appraiser. If, within 10 days of the date of
the date of delivery of the Appraisal  Notice,  the Flipper Sisters and Newco LP
agree upon an  appraiser  to  determine  the Fair Market Value of Newco LP, then
such appraiser shall be the Appraiser and shall make such  determination of Fair
Market Value within 60 days of the date of such  person's  engagement,  and such
determination  shall govern.  If the Flipper Sisters and Newco LP do not, within
such  10 day  period,  agree  as to a  single  Appraiser,  or if  the  Appraiser
appointed  as provided  above fails to  determine  such fair market value within
sixty days of the date of such  person's  engagement,  then each of the  Flipper
Sisters and Newco LP, by notice to the other,  shall appoint one  Appraiser.  If
either the Flipper  Sisters or Newco LP shall fail to appoint  such an Appraiser
within 10 days after the lapse of such 10 or 60 day period, as applicable,  then
the  Appraiser  appointed by the party that does so appoint an  Appraiser  shall
make the  determination of such Fair Market Value and such  determination  shall
govern. If two Appraisers are appointed  pursuant to the fourth sentence of this
paragraph  (c)  and  they  agree  upon  such  Fair  Market  Value,  their  joint
determination  shall govern.  If said two Appraisers  fail to reach an agreement
within 30 days after the appointment of the last Appraiser to be appointed,  the
two  Appraisers  selected  shall within 10 days following the end of such 30 day
period,  select a third Appraiser and each of the three Appraisers shall make an
appraisal  as to the Fair Market  Value within 30 days of the date of such third
Appraiser's  appointment.  In  the  event  three  Appraisers  are  appointed  as
aforesaid,  the Fair  Market  Value  shall be deemed to be an amount  derived by
averaging  the two  appraised  values  that  are  closest  to one  another.  All
decisions of the  Appraiser(s)  shall be rendered in writing and shall be signed
by the  Appraiser(s).  The Fair Market Value determined as herein provided shall
be  conclusive,  final and binding on the  parties.  The cost of the Fair Market
Value  determination  (and the other costs of the Flipper  Sisters in connection
with the  process  contemplated  by this  Section 7) shall be borne by Newco LP,
provided  that if the  Fair  Market  Value  determination  contemplated  by this
Section  7 is  completed  once but  does  not  result  in a  disposition  of the
interests  sought to be sold by the Flipper  Sisters,  the Flipper Sisters shall
bear the costs associated with any subsequent determination of Fair Market Value
(and related  expenses of the Flipper  Sisters  incurred in connection  with the
transaction  contemplated by this Section 7) if such subsequent process does not
result in a disposition.

     (d) If,  following  the  determination  of Fair Market Value of Newco LP in
accordance with the foregoing,  the Flipper Sisters desire to sell the Units and
shares of Newco GP stock held by them (collectively,  "Newco Securities"),  they
shall notify TMI,  Parent and the Lead Note  Investor of such  determination  in
writing,  and TMI,  Parent and the Lead Note Investor  shall have the right,  by
written  notice  delivered to the Flipper  Sisters  within 20 days of receipt of
such notice from the Flipper  Sisters,  to purchase (or  designate a third party
purchaser for), on a pro rata basis  determined by reference to their respective
ownership of Newco LP equity interests on an as converted basis all but not less
than all the Newco  Securities  held by the Flipper  Sisters (or, if any of such
Flipper  Sisters so elects,  all shares of capital stock of such Flipper Sister)
for cash in an amount  equal to the Fair Market Value  multiplied  by a fraction
the  numerator  of which is the number of Units held by the Flipper  Sisters and
the  denominator  of which is the total number of outstanding  Units.  If any of
TMI,  Parent Sub or the Lead Note Investor  elect not to exercise their purchase
right to the Newco  Securities in full,  the  opportunity  to purchase any Newco
Securities thus left unpurchased shall thereafter be re-allocated among those of
TMI,  Parent Sub and the Lead Note  Investor who elect to exercise on a pro rata
basis,  determined by reference to their respective ownership interests of Newco
LP equity  interests on an as converted  basis.  In the event that the Lead Note
Investor  elects not to exercise its purchase  right in full, TMI Sub and Parent
Sub shall have the right (but not the obligation) to purchase (or to designate a
third party to purchase for) any Newco  Securities thus left  unpurchased by the
Lead  Note  Investor  on a pro rata  basis,  determined  by  reference  to their
respective ownership interests of Newco LP equity interests. The closing of such
sale shall occur as soon as practicable  but in no event more than 60 days after
delivery  of  such  notice  of  purchase.  In  connection  with  such  sale  the
transferors  shall not be required  to make any  representations  or  warranties
other than (i) they have good title to the  securities  being  transferred  (ii)
they  have all  necessary  authority  to effect  such  transfer  and (iii)  such
securities are being  transferred  free and clear of all liens and  encumbrances
other  than  liens  securing  indebtedness  of  Newco  LP  and/or  Newco  GP and
encumbrances arising under this Agreement and the Ancillary Agreements.

     (e) If,  following  the  determination  of Fair Market Value of Newco LP in
accordance with the foregoing, the Flipper Sisters desire to sell the Units held
by them but neither TMI nor Parent nor the Lead Note Investor  elects to proceed
as  contemplated by clause (d) (or if one or both do elect to so proceed but the
closing  does not occur within the time period  specified  in clause  (d)),  the
Flipper  Sisters shall have the right to cause Newco LP and Newco GP (or, if the
Flipper Sisters so elect, all ownership  interests in Newco GP and all ownership
interests in the Investors  and in each entity that holds an ownership  interest
in Newco LP) to be  disposed  of,  whether by sale,  merger or  otherwise,  in a
transaction or series of related transactions (collectively, a "Sale"). The Sale
shall be on the same terms as would be obtained by  applying  Section  8.5(b) of
the Newco GP  Agreement,  except  the  parties to such Sale may be  required  to
provide different representations,  warranties and covenants to the buyer to the
extent  reasonably  required  to reflect  the  differences  in the nature of the
interests being transferred  (i.e., a transfer of the differing equity interests
of the entities owning the ownership  interests in Newco LP).  Without  limiting
the  generality of the  foregoing,  the Sale provided in this Section 7(e) shall
provide each of the Existing  Investors,  Parent, TMI and the Lead Note Investor
(as if the Lead Note Investor had converted  all of its  Convertible  Notes into
Newco  LP  equity  interests  immediately  prior  to such  sale)  with  the same
percentage  of the  consideration  to be  received  from  the  buyer as would be
obtained by applying  Section 8.5(b) of the Newco GP Agreement  (i.e., as if the
buyer had acquired all of the  ownership  interests in Newco  directly,  and the
proceeds of such acquisition  were distributed by each Investor,  Parent Sub and
TMI Sub to each  Investor  Parent,  Parent  and  TMI,  respectively);  provided,
however,  that  if  any  of the  Investors,  Parent  Sub  or  TMI  Sub  has  any
liabilities,  then such  liabilities  shall be taken into account and reduce the
consideration to be received by the owners of such entity.  Without limiting the
foregoing,  the  parties  expressly  acknowledge  and agree that the most likely
method of structuring a Sale is through the transfer of the ownership  interests
in the  various  entities  that  hold  interests  in Newco by  sale,  merger  or
otherwise  and that such a  transaction  may be fully  taxable to a party  while
being treated as a tax-free  reorganization  by others or may otherwise  involve
tax  consequences  that are different for, and  potentially  adverse to, a party
compared to the other parties to this  Agreement.  If the Flipper Sisters do not
wish to control the Sale process,  then Newco GP, Newco LP and all other parties
shall take all actions reasonably specified by the Flipper Sisters to facilitate
and effect a Sale. In either case,  Newco GP, Newco LP, each partner of Newco LP
and each of their respective  officers,  directors and stockholders shall have a
fiduciary  duty to  cooperate  fully  with  such  process  and to take all steps
reasonably  requested by the Flipper Sisters to facilitate such Sale at the best
price  available  under the  circumstances,  taking into  account  all  relevant
considerations,  one of the most  important of which is hereby  agreed to be the
need to provide liquidity to the owners of the Investors promptly even if market
conditions at the time may not be  favorable.  In no event,  however,  shall the
Flipper  Sisters  cause  Newco LP to be sold at a price of less than 80% of Fair
Market Value unless the Flipper  Sisters shall have made the offer  contemplated
by clause (f) below and such  offer  shall  have been  rejected  or the offer is
accepted  but then the sale is not  consummated.  No  partner of Newco LP or any
affiliate of any such partner shall be permitted to be, or participate, directly
or  indirectly,  as, a buyer or financing  source in  connection  with such Sale
unless (A) such affiliate is not a Control Party (as such term is defined in the
Newco GP  Agreement) of such  partner,  (B) such partner has fully  disclosed to
Newco LP and all of the other  partners  of Newco LP the role that such  partner
and/or its affiliate  shall have in the Sale and (C) the consent by such partner
to the Sale is not  required to have the consent of the Flipper  Sisters to such
Sale.

     (f) Prior to causing  Newco LP to be sold for a price less than 80% of Fair
Market  Value,  the Flipper  Sisters shall make a written offer (the "Offer") to
sell the Interests  then held by them to the other parties  hereto at a price to
be specified by the Flipper Sisters. If such Offer is accepted by written notice
to the Flipper  Sisters  within five business days of the date of receipt of the
Offer, then such Units shall be sold to such parties at the price specified at a
closing  to be held  within  30 days of such  acceptance.  If such  Offer is not
accepted within such 5 business day period,  or if such Offer is so accepted but
the closing does not occur within such 30 day period,  the Flipper Sisters shall
be free to cause a sale of Newco LP to occur at a price  not  lower  than 90% of
the price specified in the Offer and on terms not less favorable,  on the whole,
than those specified in the offer. If the Flipper Sisters desire to cause a sale
of Newco LP at a price lower than 90% of the price specified in the Offer,  then
prior to such sale the Flipper  Sisters  shall be required  again to comply with
the procedures in this Section 7(f).

     (g) For the purposes of Clauses (e) and (f) above,  the "price" involved in
a transaction  or proposed  transaction  shall be determined by reference to the
present  fair  market  value  of  the  consideration  to  be  received  in  such
transaction, taking into account all relevant considerations.

SECTION 8.        Representations and Warranties of Newco LP.
- ------------------------------------------------------------

     Newco LP shall  deliver  to each  Second  Closing  Investor  at the  Second
Closing a  disclosure  schedule  taking any  necessary  exceptions  to following
representations  and warranties (the "Newco LP Disclosure  Schedule");  provided
that the Newco LP  Disclosure  Schedule  shall be  prepared  by Newco LP in good
faith to reflect as fairly as possible the nature and scope of  exceptions  that
the parties  hereto have agreed  upon in  connection  with the other  Disclosure
Schedules  delivered  herewith.  Except as disclosed in the Newco LP  Disclosure
Schedule,  Newco LP shall  represent  and warrant to the Investors on the Second
Closing Date as follows:

8.1. Organization and Good Standing; Power and Authority;  Qualifications. Newco
LP (a) is duly organized,  validly  existing and in good standing under the laws
of  its  jurisdiction  of  organization  and  (b)  has  all  requisite   limited
partnership  power and authority to own, lease and operate its properties and to
carry on its  business as then  conducted.  Newco LP has all  requisite  limited
partnership  power and  authority  to enter into and carry out the  transactions
contemplated  by this  Agreement and the  Ancillary  Agreements to which it is a
party.  Newco  LP  is  qualified  to  transact  business  as a  foreign  limited
partnership  in, and is in good standing under the laws of the  Commonwealth  of
Virginia.

8.2. Authorization of the Documents. The execution,  delivery and performance by
Newco LP of this Agreement and each of the Ancillary Agreements to which it is a
party, and the consummation of the transactions  contemplated hereby and thereby
have been duly  authorized  by all action on the part of Newco LP (and do not or
will not require the  approval or consent of the limited  partners of Newco LP),
and this  Agreement and each of the Ancillary  Agreements to which it is a party
will constitute a legal,  valid and binding  obligation of Newco LP, enforceable
against  Newco LP in  accordance  with  its  terms  except  to the  extent  that
enforceability  may be limited by  bankruptcy,  insolvency or other similar laws
affecting  creditors'  rights generally and except to the extent that the remedy
of specific  performance and injunction and other forms of equitable  relief may
be subject to equitable defenses.

8.3.  Capitalization.  Immediately prior to the Second Closing, the ownership of
Newco  LP  shall  be as then set  forth  in the  Newco  LP  Agreement.  All such
outstanding  Limited  Partnership  Interests  will  be  validly  issued.  Except
pursuant to the Newco LP Agreement or the Newco GP Agreement, no limited partner
of Newco LP is entitled to  pre-emptive  rights.  There are not as of the Second
Closing any  outstanding  options or rights to acquire any interest in Newco LP.
Except in accordance  with the Newco LP Agreement,  Newco LP has not,  since its
inception, declared or paid any dividend or made any other distribution of cash,
stock or other property to its partners.

8.4.  Authorization  and  Issuance of  Investor  Interests.  The  authorization,
reservation,  issuance, sale and delivery of the Additional Interests to be sold
at the  Second  Closing  have  been duly  authorized  by all  requisite  limited
partnership  action on the part of Newco LP and when issued,  sold and delivered
in accordance with this Agreement, the Investor Interests will be validly issued
and outstanding,  with no personal liability  attaching to the ownership thereof
(other  than as  provided in the  DRULPA),  free and clear of any  Encumbrances,
other than  Encumbrances,  if any,  arising as a result of actions  taken by the
Investors or arising  pursuant to applicable  federal and state securities laws,
and not  subject to  preemptive  or similar  rights of  partners  of Newco LP or
others. The terms, designations,  powers, preferences and relative, optional and
other special rights, and the qualifications,  limitations and restrictions,  of
the Investor  Interests are as stated in the Newco LP Agreement and the Newco GP
Agreement.

8.5.  Financial  Statements.  Each of the  balance  sheets  included in the most
recent monthly and quarterly Newco  Financial  Statements  fairly  presented the
financial  position of the entity or entities to which it relates as of its date
and each of the  statements of  operations,  members'  capital or  stockholders'
equity  (deficit)  and cash  flows  included  in the  most  recent  monthly  and
quarterly Newco Financial Statements fairly presented the results of operations,
members' capital or retained  earnings or cash flows, as the case may be, of the
entity or entities to which it relates  for the  periods set forth  therein,  in
each case in  accordance  with GAAP  consistently  applied  during  the  periods
involved,  except as may be noted  therein  and except for the  absence of notes
thereto,  and subject to normal recurring  year-end  adjustments  which have not
been and will not be material in nature or amount.

8.6. No  Undisclosed  Liabilities.  Except as disclosed  in the Newco  Financial
Statements,  and except for normal or recurring  liabilities  incurred since the
date of the Newco  Financial  Statements  in the  ordinary  course  of  business
consistent with past practices,  Newco LP does not have any liabilities,  either
accrued,  contingent  or  otherwise,  of the type  required to be  reflected  in
financial  statements in accordance with GAAP, and whether due or to become due,
which  individually  or in the aggregate,  have had or are reasonably  likely to
have a Material Adverse Effect on Newco LP.

8.7.  Absence of Certain  Changes or Events.  Except as  disclosed  in the Newco
Financial Statements, since the date of the Newco Financial Statements, Newco LP
has conducted its business only in the ordinary  course,  and there has not been
(a) any  change,  circumstance  or event that could  reasonably  be  expected to
result in a Material  Adverse Effect on Newco LP, (b) any  declaration,  setting
aside or payment  of any  dividend  or other  distribution  with  respect to the
Investor  Interests,  (c) any material  Commitment entered into by Newco outside
the  ordinary  course of  business,  or (d) any  material  change in Newco  LP's
accounting principles, practices or methods.

8.8. No Conflict. The execution and delivery by Newco LP of this Agreement,  and
by  Newco  LP of the  Ancillary  Agreements  to  which  it is a  party,  and the
consummation by Newco of the  transactions  contemplated  hereby and thereby and
compliance  with the  provisions  hereof  and  thereof  will not (a)  violate or
conflict  with, or require any consent,  approval,  notice or filing under,  any
provision of any  domestic  (federal,  state or local) or foreign law,  statute,
rule or regulation,  or any ruling, writ, injunction,  order, judgment or decree
of any court, administrative agency or other governmental body applicable to it,
or any of its  properties  or assets other than  violations  or conflicts  which
would not reasonably be expected to have a Material  Adverse Effect on Newco LP,
(b) conflict with, or result in any violation or breach of, or constitute  (with
due notice or lapse of time, or both) a default or loss of a benefit  under,  or
cause or permit the acceleration  under, the terms,  conditions or provisions of
(i) the  Indenture or (ii) any Contract to which Newco LP is a party or to which
its  properties  or  assets is  subject  (all of which  are  listed  in  Section
8.8(b)(ii)  of the Newco LP  Disclosure  Schedule)  which  could  reasonably  be
expected  to have a  Material  Adverse  Effect  on Newco LP,  (c)  result in the
creation or imposition of any  Encumbrance  upon any of Newco LP's properties or
assets which could  reasonably be expected to have a Material  Adverse Effect on
Newco LP, or (d) violate Newco LP's organizational documents.

8.9.  Litigation;  Orders.  There  is no  Litigation  against  Newco LP which if
determined adversely to Newco LP could reasonably be expected to have a Material
Adverse  Effect  on  Newco  LP.  Newco LP is not  subject  to any  order,  writ,
injunction  or decree of any court of any  federal,  state,  municipal  or other
domestic or foreign governmental department,  commission,  board, bureau, agency
or instrumentality.

8.10. Compliance with Laws; Permits. Newco LP is and has been, since its date of
organization,  in compliance  with, and has conducted its business in compliance
with, all federal,  state,  local and foreign laws,  rules,  ordinances,  codes,
consents,  authorizations,   registrations,  regulations,  decrees,  directives,
judgments and orders, including  environmental,  applicable to it which if Newco
failed to comply could  reasonably be expected to have a Material Adverse Effect
on Newco LP. Newco LP has all Permits materially necessary in the conduct of its
business as currently conducted.  All such Permits are in full force and effect,
and no material  violations  have  occurred in respect of any such  Permits;  no
material proceeding is pending or, to the best knowledge of Newco LP, threatened
to  revoke or limit  any such  Permit;  and no such  Permit  will be  suspended,
cancelled  or  adversely  modified  in any  material  respect as a result of the
execution  and delivery of this  Agreement or the Ancillary  Agreements  and the
consummation of the transactions contemplated hereby or thereby.

8.11.  Title.  Newco  LP has good and  marketable  title to all of its  material
properties  and  assets,  real  and  personal,  and has  good  title  to all its
leasehold  interests,  in each case subject only to Encumbrances  created in the
ordinary course of business.

8.12. ERISA Matters. Each plan maintained by or contributed to by Newco LP is in
compliance  in all respects  with all  presently  applicable  provisions of law,
including,  without  limitation,  the Employee Retirement Income Security Act of
1974,  as amended,  including  the  regulations  and  published  interpretations
thereunder ("ERISA"); neither Newco LP nor any entity that is or was at any time
treated as a single employer with Newco LP under Section 414(b), (c), (m) or (o)
of the Internal Revenue Code of 1986, as amended,  including the regulations and
published  interpretations  thereunder  (the  "Code") has incurred or expects to
incur  liability  with respect to a plan subject to Title IV of ERISA or Section
412 of the Code;  and each "pension  plan" (as defined in ERISA) for which Newco
LP would have any  liability  that is intended  to be  qualified  under  Section
401(a) of the Code is so  qualified  in all  material  respects  and nothing has
occurred,  whether by action or by failure to act, which would cause the loss of
such qualification.

8.13.  Insurance.  Newco LP maintains property and casualty,  general liability,
personal injury,  director and officer and other similar types of insurance with
financially  sound and reputable  insurers that is adequate and consistent  with
industry standards.  Newco LP has not received notice from, and has no knowledge
of any threat by, any insurer (that has issued any insurance policy to Newco LP)
that such insurer  intends to deny coverage under or cancel,  discontinue or not
renew any insurance policy covering Newco LP presently in force.

8.14. Labor Relations;  Employees. Newco LP is not delinquent in payments to any
of its employees, for any wages, salaries, commissions,  bonuses or other direct
compensation  for any services  performed by the date hereof or amounts required
to be reimbursed by them to the date hereof, (ii) Newco LP is in compliance with
all applicable federal,  state and local laws, rules and regulations  respecting
employment,  employment practices, labor, terms and conditions of employment and
wages and hours except where failure to comply would not, individually or in the
aggregate,  have a Material  Adverse  Effect on Newco LP,  (iii) Newco LP is not
bound by or  subject  to (and none of its  assets or  properties  is bound by or
subject to) any written or oral,  express or implied,  commitment or arrangement
with any labor union, and no labor union has requested or, to the best knowledge
of Newco LP, has sought to represent any of the  employees,  representatives  or
agents of Newco LP, (iv) there is no labor strike, dispute, slowdown or stoppage
actually pending,  or, to the best knowledge of Newco LP, threatened  against or
involving  Newco LP, and (v) to the best  knowledge of Newco LP, no salaried key
employee has any plans to terminate his or her employment with Newco LP. Each of
the  executive  officers  of  Newco  LP who has or had  access  to  confidential
information  of Newco LP has  executed  a  confidentiality  agreement,  and such
agreements are in full force and effect.

8.15.    Agreements.

     (a) Newco LP is not a party to, or bound or subject to, any Contract, other
than (x) any  Contract  which (i)  pursuant  to its  terms,  has  expired,  been
terminated  or fully  performed  by the parties,  and in each case,  under which
Newco LP has no liability,  contingent or  otherwise,  or (ii) involves  monthly
payments to or from Newco LP (as opposed to an  indemnity  agreement  or similar
contract  under which a party is not  required to make fixed  monthly  payments)
which  monthly  payments do not  aggregate on an annual basis to  US$250,000  or
more, and in each case, is not material to the business, condition (financial or
otherwise),  operations or prospects of Newco LP and (y) as set forth in Section
8.15 of the Newco LP Disclosure Schedule.

     (b) Assuming the due execution  and delivery by the other parties  thereto,
each of such Contracts is, as of the date hereof,  legal, valid,  binding and in
full force and effect and enforceable in accordance with its terms.  There is no
breach, violation or default by Newco LP (or, to the best knowledge of Newco LP,
any other party) under any such Contract except where such breach,  violation or
default would not,  individually  or in the aggregate,  have a Material  Adverse
Effect  on  Newco  LP,  and  no  event  (including,   without  limitation,   the
consummation of the  transactions  contemplated by this Agreement)  which,  with
notice or lapse of time or both,  would (A)  constitute  a breach,  violation or
default by Newco LP (or,  to the best  knowledge  of Newco LP, any other  party)
under any such  Contract  except where such breach,  violation or default  would
not,  individually or in the aggregate,  have a Material Adverse Effect on Newco
LP,  or (B)  give  rise  to any  lien or  right  of  termination,  modification,
cancellation,  prepayment,  suspension,  limitation,  revocation or acceleration
against Newco LP under any such  Contract.  Newco LP is not or, to the knowledge
of Newco  LP,  no other  party to any of such  Contracts  (i) is in  arrears  in
respect of the  performance or  satisfaction  of the terms and conditions on its
part to be  performed  or  satisfied  under  any of such  Contracts  or (ii) has
granted or has been granted any waiver or indulgence under any of such Contracts
or has repudiated any provision thereof.

8.16.  Offering  Exemption.  Assuming  the accuracy of the  representations  and
warranties  contained in Section 5 hereof, the issuance and delivery of Investor
Interests to the Second Closing  Investors at the Second Closing are exempt from
registration under the Securities Act as in effect on the date of this Agreement
and under  applicable  state  securities  and "blue sky" laws,  as  currently in
effect.

8.17. Consents. No permit,  authorization,  consent or approval of or by, or any
notification of or filing with, any person (governmental or private) is required
by Newco LP in connection  with the execution,  delivery and performance of this
Agreement,  or by  Newco  LP in  connection  with the  execution,  delivery  and
performance of the Ancillary Agreements to which it is a party, the consummation
by Newco LP of the transactions contemplated hereby or thereby, or the issuance,
sale or delivery of the Investor Interests (other than (i) such notifications or
filings required under the HSR Act, the FCC Act and applicable  federal or state
securities laws, if any, which shall be made on a timely basis and (ii) permits,
authorizations,  consents  and  approvals  which,  if not  obtained,  could  not
reasonably be expected to have a Material Adverse Effect on Newco LP).

8.18. Brokers. No agent,  broker,  investment banker or other firm or person, is
or will be entitled to any broker's or finder's fee or any other  commission  or
similar fee from Newco LP in  connection  with this  Agreement or the  Ancillary
Agreements or any of the transactions contemplated hereby or thereby.

8.19.  Public Utility Holding Company,  Etc. Neither Newco LP nor any Subsidiary
is: (i) a "public utility company" or a "holding  company," or an "affiliate" or
a "subsidiary  company" of a "holding  company," or an "affiliate" of a " public
utility  company," a "holding  company" or a  "subsidiary  company" of a holding
company as such terms are defined in the Public Utility  Holding  Company Act of
1935,  as amended,  or (ii) a "public  utility," as defined in the Federal Power
Act, as amended,  or (iii) an  "investment  company" or an  "affiliated  person"
thereof or an "affiliated person" of any such "affiliated person," as such terms
are defined in the Investment Company Act of 1940, as amended.

8.20.    FCC.
- ------------

     (a) Section 8.20(a) of the Newco LP Disclosure Schedule contains a true and
complete list of all material Licenses, including the frequencies authorized for
and the issuance and expiration  dates of each such License,  issued to Newco LP
or Newco Sub by the FCC in  connection  with the  operation  of the Existing Sub
Business. No such License is subject to any restriction or condition which would
limit in any material respect the full operation of the Existing Sub Business as
now operated, and no proceeding,  inquiry, investigation or other administrative
action is pending or, to Newco LP's  knowledge,  threatened by or before the FCC
that would  reasonably  be expected to result in the  revocation of any material
FCC authorization or otherwise impair in any material respect the full operation
of the Existing Sub Business. The representations contained in this Section 8.20
are limited by the  statements  set forth in the section of Parent's most recent
Regulatory  Disclosure.  The statements  contained in the Regulatory  Disclosure
fully and accurately  describe,  with respect to the Existing Sub Business,  the
material legal matters and proceedings  arising under the  Communications Act of
1934, as amended, and the published rules, regulations, and policies promulgated
thereunder by the FCC.

     (b) Section 8.20(b) of the Newco LP Disclosure Schedule contains a true and
complete  list of all  material  Applications,  and  including  the  frequencies
applied for and the filing date of each such  Application,  that have been filed
by Parent or Sub or Newco LP or Newco Sub with the FCC  relating to the Existing
Sub  Business.  Neither  Newco LP nor Newco Sub is aware of any  reason  why any
Application  would not granted by the FCC.  Newco LP have  delivered to Investor
true and  complete  copies  of the  Licenses  and  Applications,  including  any
additions, amendments and other modifications thereto.

     (c) Newco Sub is the  authorized  legal holder of all the  Licenses,  other
than  Licenses held by Canadian  License Co. The Licenses are in good  standing,
are in full force and  effect,  and are  unimpaired  by any act or  omission  of
Parent, Sub or Newco LP, or any of their officers,  directors, or employees; and
the  operation of the  business of Newco LP and Newco Sub is in full  compliance
with the Licenses.  These  Licenses are sufficient for the lawful conduct of the
business  and  operation  of the  Existing Sub Business in the manner and to the
full extent they are  currently  conducted.  All material  reports,  forms,  and
statements  required to be filed with the FCC with  respect to the  Existing Sub
Business have been filed and are complete and accurate in all material respects.

     (d)  Canadian  License Co. is the  authorized  legal holder of the Canadian
License Co.  Licenses.  The Canadian  License Co. Licenses are in good standing,
are in full force and effect,  and are unimpaired by any act or omission of TMI,
Canadian License Co., or any of the officers,  directors, or employees of either
TMI or Canadian  License  Co.; and the  operation  of the  Canadian  License Co.
business is in full  compliance  with the  Canadian  License Co.  Licenses.  The
Canadian  License Co.  Licenses  are  sufficient  for the lawful  conduct of the
business and operation of Canadian License Co. All material reports,  forms, and
statements  required to be filed with Industry  Canada and the CRTC with respect
to the  Canadian  License  Co.  business  have been filed and are  complete  and
accurate in all material respects.

     (e) In 1999,  Sub had access to the  spectrum  assigned  to Sub in the 1999
coordination agreement among the North American L-band operators. Newco believes
that Newco Sub should  continue  to have access for the year in which the Second
Closing occurs to as much of this spectrum as Newco Sub is able to use.

8.21.  Restrictions.  Other than Newco LP's obligations  under the TMI Note, the
MSI Note and the Convertible  Notes,  Newco LP is not and will not be a party to
any loan agreement or other financing  document giving rise to any  obligations,
restrictions,  limitations  or  Encumbrances  with  respect  to  Newco LP or its
assets.  During any period when Parent  shall own an interest in Newco LP of 50%
or greater,  the only  contractual  obligations  of Parent  relating to Newco LP
(other than those  contained in this  Agreement  and the  Ancillary  Agreements)
shall  be  the  provisions  of  Parent's  existing  Loan  Agreements.  Following
consummation  of the First  Closing and assuming that Parent shall then own less
than a 50% Interest in Newco LP, such requirements shall cease to be applicable,
other than Parent's pledge of all of its Limited Partnership  Interests in Newco
LP to its banks and guarantors.

8.22.  Environmental  Matters.  There are,  with respect to Newco LP, no past or
present  violations of  Environmental  Law (as defined below),  nor any actions,
activities,   circumstances,   conditions,  events,  incidents,  or  contractual
obligations  which are  reasonably  likely to give rise to any  liability  which
would have a Material  Adverse Effect on Newco LP pursuant to any  Environmental
Law,  and  neither  Parent nor Newco LP has  received  any  written  notice with
respect  to any of the  foregoing  nor is  any  Litigation  pending  or,  to the
knowledge  of Parent  and Newco LP,  threatened  in  connection  with any of the
foregoing.

     (a) For purposes of this Section 8.22,  capitalized terms used herein shall
have the following meanings:

          (i)  "Environmental  Laws" shall mean,  all  applicable  provisions of
     federal,  state, local or foreign law (including  applicable  principles of
     common and civil law), statutes, ordinances, rules, regulations,  published
     standards and  directives  that have the force and effect of law,  permits,
     licenses,  judgments,  writs,  injunctions,  decrees  and  orders  enacted,
     promulgated or issued by any Public Authority, and all indemnity agreements
     and other contractual  obligations,  as in effect at such date, relating to
     (i) the  protection  of the  environment,  including  the air,  surface and
     subsurface soils, surface waters,  groundwaters and natural resources,  and
     (ii)  occupational  health and safety and  exposure of persons to Hazardous
     Materials. Environmental Laws shall include the Comprehensive Environmental
     Response,  Compensation and Liability Act, 42 U.S.C.  ss.ss.  9601 et seq.,
     and any other laws imposing or creating liability with respect to Hazardous
     Materials.

          (ii) "Hazardous  Material"  shall mean any substance  regulated by any
     Environmental Law.

          (iii)  "Public  Authority"  shall  mean any  supranational,  national,
     regional, state or local government court,  governmental agency, authority,
     board, bureau, instrumentality or regulatory body.

8.23.  Proprietary Rights. Except for matters which would not, in the aggregate,
have a Material Adverse Effect on Newco LP, (i) Newco LP is the sole owner, free
and clear of any Encumbrance, of, or has a valid license, without the payment of
any royalty  except with  respect to  off-the-shelf  software  and  otherwise on
commercially  reasonable  terms,  to, all U.S. and foreign  trademarks,  service
marks, logos,  designs,  trade names, internet domain names and corporate names,
and the goodwill of the business  connected  therewith and  symbolized  thereby,
patents,  registered  designs,  copyrights,  computer  software  and  databases,
whether or not  registered,  web sites and web pages and related  items (and all
intellectual property and proprietary rights incorporated therein) and all other
trade secrets,  research and development,  formulae,  know-how,  proprietary and
intellectual   property   rights  and   information,   including   all   grants,
registrations and applications relating thereto (collectively,  the "Proprietary
Rights")  described in Section 8.23 of the Newco LP Disclosure  Schedule,  (such
Proprietary  Rights owned by or licensed to Newco LP,  collectively,  the "Newco
Rights");  (ii)  Newco LP has  taken,  and will  take,  all  actions  which  are
necessary  or  advisable  in order to protect the Newco  Rights,  and to acquire
Proprietary  Rights,   consistent  with  prudent  commercial  practices  in  the
telecommunications  industry;  (iii) Newco LP's  rights in the Newco  Rights are
valid and enforceable; (iv) neither Parent nor Newco LP has received any demand,
claim,  notice or  inquiry  from any  person or entity in  respect  of the Newco
Rights which challenges,  threatens to challenge or inquires as to whether there
is any basis to  challenge,  the  validity of, or the rights of Newco LP in, any
such Newco  Rights,  and neither  Parent nor Newco LP knows of any basis for any
such challenge; (v) Newco LP is not in violation or infringement of, and has not
violated or  infringed,  any  Proprietary  Rights of any other person or entity;
(vi) to the  knowledge of Parent and Newco LP, no person or entity is infringing
any Newco Rights;  and (vii) except on an arm's-length basis for value and other
commercially reasonable terms, Newco LP has not granted any license with respect
to any Newco Rights to any person or entity.

8.24.  Disclosure.  Neither this Agreement nor any Ancillary  Agreement (nor any
certificate  or  instrument  executed in connection  with this  Agreement or any
Ancillary Agreement) furnished or made to the Investors by or on behalf of Newco
LP omits to state a material  fact  required  to be stated  herein or therein or
necessary in order to make the statements  contained herein or therein, in light
of the circumstances under which they were made, not misleading.

SECTION 9.        Sole Economics.
- --------------------------------

     The  parties  acknowledge  and agree  that the  economic  interests  of the
parties in the joint business  contemplated hereby and by the Newco LP Agreement
and the Asset Sale Agreements are intended to be in the proportions set forth in
the  Newco  LP  Agreement,  and  that to the  extent  any  party  (or any of its
affiliates) derives any economic benefit, or incurs any economic detriment, from
the ownership or operation of any of the Related Entities, the parties will make
equitable  arrangements  for the sharing of such  benefit or  detriment as shall
reflect, as closely as practicable,  the proportional  ownership in Newco LP set
forth from time to time in the Newco LP Agreement.

SECTION 10.       Certain Other Covenants.
- -----------------------------------------

10.1.  Notification of Certain Matters. Each party shall notify each other party
in writing of its  discovery of any matter that would render any of such party's
representations  and  warranties  contained  herein  untrue or  incorrect in any
material respect.

10.2. Hart Scott-Rodino  Filing. The parties shall make any appropriate  filings
of  Notification  and Report  Forms  pursuant to the HSR Act with respect to the
transactions  contemplated  hereby in a timely  manner  (i.e.,  sufficiently  in
advance of the anticipated  closings so as to be not likely to result in a delay
of  the  closings)  and  supply  as  promptly  as  practicable   any  additional
information and documentary  material that may be requested  pursuant to the HSR
Act and take all other actions  reasonably  necessary to cause the expiration or
termination  of the  applicable  waiting  periods  under  the HSR Act as soon as
practicable.

10.3.    Certain Additional Covenants.
- -------------------------------------

     (a) Parent shall cause  Parent Sub, Sub and Newco LLC to promptly  perform,
and Parent hereby  unconditionally  guarantees  the prompt  performance by Newco
LLC, Sub, and Parent Sub of, their respective  obligations  under this Agreement
and the Ancillary Agreements,  including, without limitation, the obligations of
Sub to consummate the transactions contemplated by the Ancillary Agreements.

     (b) Until after the First  Closing,  Parent shall not, and shall not permit
any of its direct or indirect  subsidiaries to, engage in any transaction  which
would have the effect of transferring  ultimate  control of Sub to any person or
entity not controlled by Parent,  or of divesting  Parent of ultimate control of
Sub,  without  the  consent of the Lead Note  Investor,  TMI and a  majority  in
interest of the Existing  Investors,  which  consent  shall not be  unreasonably
withheld if (i) in connection  with a bona fide  disposition  of assets in which
the stock or assets of Sub constitute less than 50% in terms of value,  ultimate
control of Sub is  transferred  to a person or entity which shall have agreed in
writing to be bound by the  provisions  hereof  applicable to Parent,  (ii) such
transaction  shall not materially  interfere with or impede the  consummation of
the transactions contemplated by this Agreement and/or the Ancillary Agreements,
and (iii) Parent  shall  expressly  acknowledge  in writing that it shall remain
fully liable in respect of all liabilities and obligations  (including indemnity
obligations)  undertaken by it under this Agreement and the Ancillary Agreements
even if such liabilities or obligations  arise from actions taken (or not taken)
by such transferee.

     (c) Each party  hereto  shall use all  commercially  reasonable  efforts to
satisfy at the appropriate  times all closing  conditions to the consummation of
the First Closing and the Second Closing, the Parent Conversions,  and the other
transactions contemplated hereby and by the Ancillary Agreements. Without in any
way  limiting  the  generality  of the  foregoing,  each  party  shall  use  all
reasonable best efforts to cause the conditions  specified  herein as conditions
to the First  Closing  that are within such  party's  control to be satisfied by
October 31, 2001.

     (d) From the date hereof until the First Closing,  Parent shall not, permit
Newco LLC or Sub to become bound by any contract, undertaking or obligation that
would (i)  prohibit,  restrict,  require  any  consent  for, or give rise to any
obligation as a result of, the transactions contemplated hereby or the Ancillary
Agreements,  other than standard  anti-assignability  clauses in ordinary course
agreements,  provided that the inability to transfer such agreements to Newco LP
would not have a Material  Adverse Effect on Newco LP; (ii) be considered out of
the ordinary  course of business  for Parent,  Sub or Newco,  including  without
limitation  non-preemptable  service contracts,  prepaid contracts and contracts
giving  preferential  access to spectrum or otherwise providing customers with a
preferred  status;  or (iii) obligate Parent,  Sub or Newco to commit to provide
both a specified amount of satellite  transmission  power and a specified amount
of bandwidth,  thereby depleting Parent's or, or Sub's available satellite-based
communications network power and bandwidth capacity.

     (e) From the date hereof until the First Closing, without the prior written
consent of Parent,  Newco,  the Lead  Investor and a majority in interest of the
Existing Investors,  which consent shall not be unreasonably withheld, TMI shall
not, and shall not permit TMI Sub to, become bound by any contract,  undertaking
or  obligation  that would (i) prohibit,  restrict,  require any consent for, or
give rise to any obligation as a result of, the transactions contemplated hereby
or the Ancillary Agreements,  other than standard  anti-assignability clauses in
ordinary  course  agreements,  provided  that the  inability  to  transfer  such
agreements  to Newco LP would not have a  Material  Adverse  Effect on Newco LP;
(ii) be  considered  out of the ordinary  course of business for TMI and TMI Sub
(if TMI or TMI Sub had  entered  into such  contract or  obligation),  including
without  limitation  non-preemptable  service  contracts,  prepaid contracts and
contracts  giving   preferential  access  to  spectrum  or  otherwise  providing
customers  with a preferred  status;  or (iii) obligate TMI to commit to provide
both a specified amount of satellite  transmission  power and a specified amount
of bandwidth,  thereby depleting TMI's available satellite-based  communications
network power and bandwidth capacity;  provided,  however, that TMI is permitted
after  the date  hereof to (A)  enter  into an  agreement  with  Telecom  Mexico
substantially  in  the  form  of  the  proposal  dated  September  21,  2000  as
resubmitted by letter dated November 15, 2000 from TMI to Telecommunicaciones de
Mexico,  and (B) enter into service provider contracts that require a prepayment
by the customer  provided such contracts are entered into in the ordinary course
of  TMI's  business  consistent  with  past  practice  and  do not  involve  any
affiliates of TMI. At the First Closing,  TMI's remaining  obligations under any
contract  of the types  contemplated  by  clauses  (A) and (B) of the  preceding
sentence shall be assigned to Newco (or, if appropriate,  Canadian  License Co.)
along  with an  amount of cash  corresponding  to the  amount of any  prepayment
relating to such remaining obligations.

     (f) Investment Company Act. Until after the Second Closing, Parent will not
become  an  "investment  company"  or  an  "affiliated  person"  thereof  or  an
"affiliated  person" of any such "affiliated  person," as such terms are defined
in the Investment Company Act of 1940, as amended.

10.4.  Transactions  with  Affiliates.  Except  as set  forth  herein  or in the
Ancillary  Agreements,  Newco will not, prior to or in connection with the First
Closing, engage in any transaction or group of related transactions  (including,
without limitation,  the purchase,  lease, sale or exchange of properties of any
kind or the rendering of any service) with any affiliate, except in the ordinary
course of  business  and  pursuant  to the  reasonable  requirements  of Newco's
business  and upon fair and  reasonable  terms no less  favorable  to Newco than
would be obtainable in a comparable  arm's-length  transaction with a person not
an  affiliate.  As used  herein,  the term  "affiliate"  shall mean any officer,
director,  10% or greater stockholder,  or any family member of any such person,
or any  business  entity  controlled  by any such person;  without  limiting the
generality of the foregoing,  Parent and each of its subsidiaries and affiliates
shall be deemed to be affiliates of Newco.

10.5.  Reservation  of Common  Stock.  From and after the Second  Closing  Date,
Parent  shall at all times  reserve  and keep  available  out of its  authorized
shares of common  stock,  solely for the purpose of issue or  delivery  upon the
consummation of the Parent  Conversions,  the maximum number of shares of Parent
Common Stock that may be issuable or deliverable in connection  therewith.  Such
shares of Parent Common Stock are or will be duly authorized and, when issued or
delivered in  accordance  with the  provisions  of Section 3.1 hereof,  shall be
validly issued, fully paid and non-assessable.

10.6.  Use of  Proceeds.  The amount  received by Newco LP at the First  Closing
shall be used as follows: (a) US$45,000,000 shall be paid to Sub pursuant to the
Amended and Restated Sub Asset Sale Agreement, (b) US$7,500,000 shall be paid to
TMI pursuant to the TMI Asset Sale Agreements and (c) the remaining US$2,500,000
shall be used for general corporate purposes.

10.7.    Financial Information.
- ------------------------------

     From the date hereof through the Second  Closing Date,  Newco shall furnish
to TMI, Parent and the Investors the following financial statements:

     (a) within 115 days after the end of each fiscal year of Newco,  an audited
balance sheet of Newco as of the end of such fiscal year and the related audited
statements of  operations,  members'  capital or  stockholders'  equity and cash
flows for the fiscal  year then  ended,  prepared  in  accordance  with GAAP and
certified by a firm of independent public  accountants  selected by the Board of
Directors of Newco; and

     (b)  within  45 days  after  the end of each  fiscal  month  of  Newco,  an
unaudited  balance  sheet of Newco as of the end of such  fiscal  month  and the
related unaudited statements of operations,  stockholders' equity and cash flows
for the fiscal month then ended,  prepared in accordance  with GAAP,  except for
the  absence  of  notes  thereto  and  subject  to  normal  recurring  year  end
adjustments which will not be material in nature or amount, and certified by the
chief financial  officer of Newco (the most recent of which shall be referred to
herein as the "Newco Financial Statements").

10.8.    FCC Application; Next-Gen Satellite.
- --------------------------------------------

     (a)  Without  the  consent of TMI,  Parent,  the Lead Note  Investor  and a
majority in interest  of the  Existing  Investors,  which  consent  shall not be
withheld  unreasonably,  neither the FCC  Applications  nor the Industry  Canada
Application shall be amended in any material respect.

     (b) From and after the First Closing,  Newco and Canadian License Co. will,
at their own expense,  use all  commercially  reasonable  efforts to obtain such
licenses, consents,  authorizations and approvals of the FCC and Industry Canada
as are  necessary  for Newco LP and  Canadian  License  Co. or their  respective
successors to develop a next-generation mobile satellite system substantially in
accordance with the FCC Applications and Industry Canada Application.  Newco and
Canadian License Co. will use all commercially  reasonable  efforts to develop a
next-generation  mobile  satellite  system for Newco and Canadian License Co. in
accordance  with such licenses,  consents,  authorizations  and approvals as are
granted by the FCC and Industry Canada pursuant to such Applications.

     (c) The parties agree not to interfere with the granting to Newco, Canadian
License  Co.  or  their  respective  successors,  of  the  licenses,   consents,
authorizations  and approvals  contemplated by the FCC Applications and Industry
Canada  Application,  and not to attempt to take away or otherwise deprive Newco
or  Canadian  License  Co., or their  respective  successors,  of any  licenses,
consents, authorizations and approvals which are granted to them pursuant to the
FCC Applications and Industry Canada Application.

10.9.  Operations  Plan.  The parties agree to proceed in  accordance  with this
Section 10.9,  except as otherwise  determined by a vote of the Limited Partners
of Newco and the Note  Investors (as if the Note  Investors had converted all of
their  Convertible  Notes into  equity  interests  of Newco LP) holding at least
eighty  percent (80%) of the  Percentage  Interests held by all Newco LP limited
partners and the Note  Investors (as if the Note  Investors had converted all of
their  Convertible  Notes into equity  interests of Newco LP),  from the date of
First  Closing  until the earlier of the Second  Closing Date or  September  30,
2002:

     (a) The parties agree that Newco shall adopt the  Operations  Plan attached
hereto as Exhibit R (the "Operations Plan");

     (b) The parties agree that Newco will implement the  combination of TMI and
Sub operations (location,  platform, services, employees) as contemplated in the
Operations Plan;

     (c) Subject to paragraph (b) above, Newco will have the right to modify its
operations on an ongoing basis  provided that such  modification  does not cause
Newco to go from  being  cash  positive  during  any  calendar  quarter  to cash
negative during such calendar quarter or any quarter thereafter; and

     (d) Newco shall  promote and support the marketing and sale of TMI's packet
data and TAMS  services  provided  that such  services are  profitable  and cash
positive or reasonably  expected to be profitable and cash positive.  Subject to
the immediately preceding sentence,  Newco will use all commercially  reasonable
efforts to avoid  liability  under Section 3.8(c) under the Amended and Restated
Sub Asset Sale Agreement.

10.10.   Non-compete; Non-solicitation; Exclusivity as to L-Band.
- ----------------------------------------------------------------

     (a) Without the express prior written consent of Newco LP and the Lead Note
Investor,  neither (i) Parent nor any  subsidiary of Parent nor (ii) TMI nor any
subsidiary  of TMI shall,  at any time during the  two-year  period  immediately
following the First Closing,  directly or indirectly,  own,  manage,  control or
participate in the ownership, management or control of, any entity that directly
competes  with the Existing Sub Business or the Existing TMI  Business,  in each
case, as such businesses were conducted  immediately prior to the First Closing;
and provided,  further, that the foregoing shall not prohibit Parent or TMI from
owning  as a  passive  investment  5% or less of the  outstanding  equity of any
publicly-traded entity.

     (b) Parent and TMI agree that they and their respective  subsidiaries shall
not,  for a period of one year  after the First  Closing,  actively  solicit  or
attempt to solicit,  without the  express  written  consent of Newco LP, any key
employee of Newco LP or any  subsidiary of Newco LP. Newco LP agrees that it and
its respective  subsidiaries shall not, for a period of one year after the First
Closing,  actively  solicit or attempt to solicit,  without the express  written
consent of the affected party, any key employee of TMI or Parent or any of their
respective  subsidiaries.  Notwithstanding  the foregoing,  this  prohibition on
solicitation does not apply to actions taken by a party either:  (a) as a result
of an employee's  affirmative  response to a general  recruitment effort carried
out through a public solicitation or general solicitation, or (b) as a result of
an employee's initiative.  For purposes of this paragraph, key employees include
supervisory  personnel,  executives,  personnel  in  charge  of any  department,
section or  subdivision  of the  company  and  project,  contract  managers  (or
directors),  and senior  personnel and technical  specialists  on any individual
project or projects.

     (c)  Parent,  Sub,  Newco  and TMI agree  that  they will take all  actions
necessary or desirable  (i) for Newco Sub to remain the only entity  licensed by
the FCC to operate one or more Mobile Satellite Service satellites in the L-band
(i.e.,  1525-1559/1626.5-1660.5 MHz) and (ii) for no L-band earth stations to be
licensed  by the FCC to  operate  in the United  States in  connection  with any
non-U.S.  licensed L-band  satellites;  and (iii) to maximize the scope of those
licenses (including the spectrum coordinated with respect thereto).

10.11.   Survival of Representations, Warranties, Agreements and Covenants;
         Indemnifications.
- ---------------------------------------------------------------------------

     (a) Survival.  All  representations  and warranties  made in or pursuant to
this  Agreement  and in or pursuant to the  Ancillary  Agreements  shall survive
until  two  years  after  the date made  (except  that the  representations  and
warranties  made in Sections  4.8(b)(i)  and  8.8(b)(i)  shall survive until the
expiration  of the statute of  limitations  applicable to any claims that may be
made by the holders of the Series A and Series B 12 1/4%  Senior  Notes due 2008
issued  by  Holdings).  A  party's  rights  to pursue  claims  for  breaches  of
representations  and warranties shall in no way be affected by any investigation
or  knowledge  of the subject  matter  thereof made by or on behalf of any party
hereto, except as set forth in clause (j) below.

     (b)  Indemnification  by Parent.  Parent shall  indemnify and hold harmless
each Investor and (without  duplication of remedies)  Newco from and against all
damages,  losses,  claims,  liabilities  and  obligations,  costs  and  expenses
(including  attorneys' fees) ("Losses")  arising in any way out of or related to
(i) the breach by Parent,  Newco, Motient  Communications,  Sub or Parent Sub of
any  representation  or warranty  made to the  Investors  by Parent,  Newco LLC,
Newco,  Motient  Communications,  Sub or Parent Sub  herein or in any  Ancillary
Agreement or in any document delivered  pursuant hereto or thereto,  or (ii) the
breach by  Parent,  Newco,  Motient  Communications,  Sub,  or Parent Sub of any
covenant or agreement  contained herein or in any Ancillary  Agreement or in any
document delivered  pursuant hereto or thereto.  Parent shall indemnify and hold
harmless TMI from and against all Losses arising in any way out of or related to
(i) the breach by Parent,  Sub or Parent Sub of any  representation  or warranty
made to TMI by Parent, Sub or Parent Sub herein or in any Ancillary Agreement or
in any  document  delivered  pursuant  hereto or thereto,  or (ii) the breach by
Parent,  Sub, or Parent Sub of any covenant or agreement  contained herein or in
any Ancillary Agreement or in any document delivered pursuant hereto or thereto.
For purposes of this Section 10.11(b),  and 10.11(f) below, the terms "material"
and  "Material  Adverse  Effect",  and  other  materiality   qualifiers  in  the
representations and warranties  contained herein or in the Ancillary  Agreements
and in any documents  delivered  pursuant hereto or thereto,  shall be deemed to
refer to  matters,  and  groups of related  matters,  that have a  financial  or
economic  impact,  or are capable of having a financial or economic  impact,  of
US$100,000  or more.  For purposes of the foregoing  sentence,  matters shall be
considered to be within "groups of related  matters" if they relate to any given
Section of the  representations  and  warranties.  (For purposes of illustration
only,  Section  4.6 would be  deemed to be  breached  if  Parent  had  failed to
disclose a liability  of  US$25,000  and a liability  of  US$90,000,  but not if
Parent had failed to disclose seven liabilities of US$10,000 each.).

     (c)  Indemnification  by Newco. Newco shall indemnify and hold harmless TMI
and each  Investor  from and  against  all  Losses  arising in any way out of or
related to (i) the breach by Newco of any  representation  or  warranty  made by
Newco herein or in any Ancillary Agreement or document delivered pursuant hereto
or thereto,  or (ii) the breach by Newco of any covenant or agreement  contained
herein or in any Ancillary  Agreement or document  delivered  pursuant hereto or
thereto.

     (d) No Duplication of Remedies.  To the extent any party may have more than
one remedy for any Losses  incurred by it, it may pursue all available  remedies
but in no event shall be entitled to collect and retain any amount  hereunder in
excess of its Losses.

     (e)  Indemnification  by Investors.  Each Investor shall indemnify and hold
harmless the other parties hereto from and against all Losses arising in any way
out of or related to (i) the breach by such  Investor of any  representation  or
warranty  made by such Investor  herein or in any Ancillary  Agreement or in any
document  delivered  pursuant  hereto  or  thereto,  or (ii) the  breach by such
Investor  of any  covenant or  agreement  contained  herein or in any  Ancillary
Agreement or in any document delivered pursuant hereto or thereto.

     (f) Indemnification by TMI. TMI shall indemnify and hold harmless the other
parties  hereto from and against all Losses arising in any way out of or related
to (i) the breach by TMI or TMI Sub of any  representation  or warranty  made by
such party herein or in any  Ancillary  Agreement  or in any document  delivered
pursuant  hereto or thereto or (ii) the breach by TMI or TMI Sub of any covenant
or agreement  contained herein or in any Ancillary  Agreement or in any document
delivered pursuant hereto or thereto.

     (g) Notice of Claims.  All claims for  indemnification  hereunder  shall be
resolved in accordance with the following procedures:

          (i) If the party seeking indemnification (the "Indemnified Party") has
     incurred or  reasonably  believes  that it may incur any  Losses,  it shall
     deliver   promptly   written   notice  to  the   indemnifying   party  (the
     "Indemnifying Party"), setting forth the nature and amount of the Losses or
     potential Losses, if possible, and further referencing the sections of this
     Agreement or in any other document delivered pursuant hereto upon which the
     claim for indemnification  for such Losses is based (a "Claim Notice").  If
     an Indemnified  Party receives  notice of a third-party  claim for which it
     intends to seek indemnification  hereunder,  it shall give the Indemnifying
     Party  written  notice  of such  claim,  so that the  Indemnifying  Party's
     defense of such claim under this  Agreement may be timely  instituted.  The
     failure by an  Indemnified  Party to provide such written  notice shall not
     constitute a waiver of the  Indemnified  Party's right to indemnity  unless
     such failure has prejudiced the Indemnifying Party's ability to defend such
     claim, and then only to the extent of such prejudice.

          (ii) If,  after  receiving  a Claim  Notice,  the  Indemnifying  Party
     desires to dispute such claim or the amount claimed in the Claim Notice, it
     shall deliver to the Indemnified Party a written objection to such claim or
     payment  setting forth the basis for disputing such claim or payment.  Such
     notice shall be delivered  within thirty (30) days after the date the Claim
     Notice to which it relates is received  by the  Indemnifying  Party.  If no
     such  notice is  received  within the  aforementioned  30-day  period,  the
     Indemnified  Party  shall be  entitled  to payment for such Losses from the
     Indemnifying Party within ten (10) days of the end of such 30-day objection
     period.

          (iii) If the Indemnifying Party shall agree that it is responsible for
     all amounts that may be recovered in connection  with a third-party  claim,
     action or suit  (including  waiving  any  deductible  or limit  that  might
     otherwise apply under this Section 10.11) the Indemnifying Party shall have
     the right to conduct and control through counsel of its own choosing, which
     counsel  shall be  reasonably  acceptable  to the  Indemnified  Party,  any
     third-party claim,  action or suit;  provided,  that the Indemnifying Party
     (x) demonstrates to the Indemnified Party's reasonable satisfaction that it
     has the financial ability to mount an appropriate defense of such claim and
     (y) diligently contests and defends such claim. The Indemnified Party shall
     be entitled at any time, at its own cost and expense (except that such cost
     and  expense  shall be paid by the  Indemnifying  Party if the  Indemnified
     Party reasonably  determines that the Indemnifying  Party is not adequately
     representing  or,  because of a conflict of  interest,  may not  adequately
     represent the interests of the  Indemnified  Party) to  participate in such
     defense and to be represented by attorneys of its choosing. Except with the
     prior written  consent of the Indemnified  Party no Indemnifying  Party, in
     the  defense of such  claim or  litigation,  shall  consent to entry of any
     judgment or order, interim or otherwise,  or enter into any settlement that
     provides  for  injunctive  or  other   nonmonetary   relief  affecting  the
     Indemnified Party or that does not include as an unconditional term thereof
     the giving by each  claimant or  plaintiff to such  Indemnified  Party of a
     release from all liability with respect to such claim or litigation.

          (iv) In the event that the Indemnifying Party does not elect to defend
     against any third-party  claim,  the  Indemnified  Party may defend against
     such claim in such manner as it may deem  appropriate and the  Indemnifying
     Party  shall be  liable  for any  legal  expenses  reasonably  incurred  in
     connection with such defense; provided, however, that the Indemnified Party
     shall not,  without the consent of the  Indemnifying  Party,  which consent
     shall  not be  unreasonably  withheld,  settle or  consent  to the entry of
     judgment with respect to such third-party claim.

          (v) In the event of any claim by a third  party,  the  parties  hereto
     agree that they will cooperate fully with each other in connection with the
     defense or settlement of such matter.

     (h) Limitation on Amounts. The Indemnifying Party shall not be obligated to
pay any amounts for  indemnification  under this  Section  10.11 with respect to
breaches of representations  and warranties until the aggregate  indemnification
obligation of such Indemnifying  Party hereunder exceeds  US$500,000,  whereupon
the Indemnifying Party shall be liable for all amounts for which indemnification
may be sought which exceed  US$500,000.  Notwithstanding  the  foregoing,  in no
event  shall the  aggregate  liability  of (v)  Parent  and Newco to the  Second
Closing Investors exceed (i) US$100,000,000 (less any amount theretofore paid by
Parent and/or Newco to the Second Closing  Investors  pursuant to Section 7.9 of
the June Investment Agreement) except in the case of any breach by Parent or Sub
of the  representations  and warranties made in Sections 4.8(b)(i) or 8.8(b)(i);
(w) Parent and Newco to the Note Investors exceed US$52,500,000, (x) TMI (or the
obligations of Parent to TMI) exceed the sum of the following  amounts:  (i) the
$7.5 million in cash paid to TMI pursuant to the TMI-Newco Asset Sale Agreement,
(ii) the  initial  principal  amount of the TMI Note and  (iii) the fair  market
value of the TMI Interest as of the date of breach (determined as if such breach
had not  occurred);  (y) any Note  Investor  exceed  (i) in the  event the First
Closing has not yet occurred, such Note Investor's commitment under Section 1.2,
and (ii) in the event the First Closing has occurred,  the outstanding principal
amount of the  Convertible  Note(s)  purchased by such Note Investor plus if the
Convertible Note(s) purchased by such Note Investor shall have been converted in
part or in full, the fair market value of such Note Investor's interest in Newco
as of the date of breach  (determined as if such breach had not  occurred);  and
(z) any Second Closing  Investor  exceed (i) in the event the Second Closing has
not yet occurred,  such Second Closing Investor's  commitment under Section 2.1,
and (ii) in the event the Second Closing has occurred,  the fair market value of
such  Second  Closing  Investor's  interest  in Newco  as of the date of  breach
(determined as if such breach had not occurred).  Parent, Newco and the Existing
Investors  further  agree  that  any sums  paid by  Parent  and/or  Newco to the
Existing Investors pursuant to this Section 10.11 shall reduce the amount of the
cap on  Parent's  and  Newco's  liability  contained  in the second  sentence of
Section  7.9(g) of the June  Investment  Agreement on a dollar for dollar basis.
The  foregoing  limits on  indemnification  shall not apply to any claims  under
Section 9 hereof or to any claims for fraud or willful breach.

     (i) Force  Majeure.  Notwithstanding  any other  provision  of this Section
10.11,  no party shall be liable for any failure of  performance of the terms of
this  Agreement  due  solely  to acts of God,  fires,  floods  or other  natural
catastrophes;  national  emergencies,  insurrections,  riots or  wars;  strikes,
lockouts,  work  stoppages  or other  labor  difficulties  beyond  such  party's
reasonable control.

     (j) Knowledge.  Notwithstanding  any other provision of this Section 10.11,
Parent  shall have no  liability  to any  Investor as to any  representation  or
warranty relating to Newco if such Investor did know that the  representation or
warranty was false when made.

     (k) Exclusive Remedy.  Indemnification pursuant to this Section 10.11 shall
be the exclusive remedy for any breach of  representations  and warranties or of
any  covenant or  agreement  in this  Agreement by any party or any other matter
pertaining to this Agreement or the transactions contemplated hereby, other than
Losses  relating  to other  written  agreements  between  the parties and Losses
relating to fraud or violation of securities laws; provided that nothing in this
Section 10.11 shall prevent any party from obtaining  equitable  relief in order
to require another party to perform its obligations hereunder.

     (l) Claims  Relating to Section 6.10. No claim may be asserted  against TMI
hereunder with respect to Section 6.10 hereof except to the extent of any claims
asserted  against Newco (or losses suffered by Newco) arising out of or relating
to claims by creditors of TMI.

10.12. GTIS Contract Amendment. TMI will use all commercially reasonable efforts
to procure the GTIS Contract Amendment within 120 days of the date hereof.

10.13.  Newco/Newco Sub Management Agreement.  Upon the First Closing,  Newco LP
will enter into a shared  services  agreement with Newco Sub,  pursuant to which
Newco LP will provide certain  management and related services to Newco Sub, and
pursuant  to which Newco Sub will have  authority  to direct the  operations  of
Newco LP and its  affiliates,  to the extent  required by the FCC in  connection
with the  licenses it issues to Newco Sub, to ensure  compliance  with FCC rules
and  regulations.  To the  extent  required  by the FCC in  connection  with the
Licenses  held by Newco Sub,  such  agreement  shall  provide Newco Sub with the
authority to direct its  affiliates'  operations to insure  compliance  with FCC
rules and regulations.

10.14. Employee Confidentiality.  Each of the parties agrees that it shall cause
its  employees  who are engaged in work on behalf of or for the benefit of Newco
after the date hereof to execute an agreement  providing that all work performed
by  such  employee  for  Newco  shall  be  considered  works  for  hire  and all
proprietary rights therein shall be owned by Newco; provided,  that with respect
to employees of Telcom Ventures or its affiliates, the foregoing agreement shall
in all cases be  subject  to the terms and  conditions  of that  certain  Patent
Assignment Agreement, dated as of the date hereof.

10.15. Certain Releases and Consents. TMI shall obtain, as of the First Closing,
(i) the release by BCE of BCE's security  interest in the assets of TMI and (ii)
the  consent of BCE  pursuant  to the  Indemnity  Agreement  dated June 30, 1993
between TMI and BCE Inc.

10.16.  Certain  Sales Tax. In regard to the  tangible  personal  property to be
transferred  by TMI to ULC  pursuant to the TMI-ULC  Asset Sale  Agreement,  the
parties will use reasonable  commercial  efforts to reduce or eliminate the tax,
if any,  payable by ULC pursuant to the Ontario  Retail Sales Tax Act, RSO 1990,
c. R31, as amended,  provided that such reasonable  commercial efforts shall not
be construed to require any party to give an opinion, representation or warranty
to any other party.

10.17. Appointment of Investor Group Designees.  Without in any way limiting any
Investor's  right  to  vote  or  transfer  its  Investor  Interest  in its  sole
discretion  or to  otherwise  exercise  its rights or receive  the  benefits  of
ownership of such Investor Interest  (subject,  in each case to the limitations,
restrictions  and other  provisions  contained in the Newco LP Agreement),  each
Existing Investor hereby irrevocably  delegates the power and authority relating
to the exercise of the Parent Conversions,  and the matters set forth in clauses
(i) through (iv) below, to such Existing  Investor's  Investor Group Designee as
set forth on  Schedule  IV hereto  (each,  an  "Investor  Group  Designee")  and
appoints such Investor Group Designee as its true and lawful agent and attorney,
for and in the name,  place and stead of such Existing  Investor (i) to exercise
at any time the right to deliver a Conversion  Notice,  (ii) to request a Parent
Conversion,  (iii) to exercise such Existing Investor's rights under Section 3.1
of this  Agreement and (iv) to send or receive  notices,  and make elections and
decisions of any type,  under this  Agreement.  Each  Existing  Investor  hereby
affirms that this grant of power and  authority  may under no  circumstances  be
revoked  except  with the prior  written  consent  of such  Existing  Investor's
Investor Group Designee and Newco LP, which shall not be unreasonably  withheld.
The authority given to any Investor Group Designee  hereunder may be transferred
by such  Investor  Group  Designee to any single person or entity upon notice to
Newco  LP,  but in no  event  shall  there be more  than  three  Investor  Group
Designees.

10.18.  Release under Indenture.  Parent shall use all  commercially  reasonable
efforts to have Sub released from its obligation  under its Subsidiary  Guaranty
(as defined in the  Indenture)  by the Trustee (as defined in the  Indenture) in
accordance with Section 11.05 of the Indenture as soon as reasonably practicable
after the First Closing. Parent shall deliver to TMI and each of the Investors a
copy of such release.

10.19.   No Waiver by Newco LP.
- ------------------------------

     Prior to the First Closing,  Newco LP and its subsidiaries  shall not waive
nor  consent  to any waiver of any of their  rights  under any of the Asset Sale
Agreements to which any of them is a party, or amend or consent to the amendment
of such agreements,  without the prior written consent of the Lead Note Investor
(which consent shall not be unreasonably withheld, delayed or conditioned).

SECTION 11.       Termination.
- -----------------------------

11.1. Termination. (a) If the First Closing shall not have occurred on or before
January 1, 2002,  any party who is not in  material  breach  hereunder  shall be
entitled to  terminate  this  Agreement by written  notice to the other  parties
hereto.

     (b) If the First Closing  shall have occurred but the Second  Closing shall
not have occurred by June 30, 2003, either of Newco LP (by vote of a majority of
the  disinterested  directors  of Newco  GP) on the one hand,  and the  Existing
Investors on the other hand,  provided that such party is not in material breach
hereunder,  shall be entitled to terminate the provisions of Section 2 hereof by
written notice to the other parties hereto,  but the remainder of this Agreement
shall remain in full force and effect.

11.2. Termination Upon Breach. Prior to the First Closing, if any party shall be
in material breach hereunder  (understood to mean a breach which would allow one
or more of the other  parties to decline to close),  and such  breach  shall not
have been cured  within 30 days of written  notice  thereof,  then any party who
shall be  entitled  to decline to close  shall be  entitled  to  terminate  this
Agreement by notice to the other parties hereto.

11.3. Consequences of Termination. In the event the First Closing does not occur
for reasons other than a breach by one or more of the parties hereto, each party
shall pay its own costs and expenses in connection  herewith,  except that Newco
shall pay the  reasonable  costs and  expenses  incurred by Parent,  TMI and the
Investors in connection with the transactions  contemplated  hereby as set forth
in Section 23. In the event the First Closing does not occur because of a breach
by one or more of the  parties  hereto,  such party shall be liable to the other
parties  hereto (i) in the case of a breach that was not  willful,  only for the
reasonable costs and expenses incurred by the other parties hereto in connection
with the transactions contemplated hereby, and (ii) in the case of a breach that
was willful,  for all Losses  incurred by the other parties  resulting from such
breach  (including  without  limitation  their  reasonable costs and expenses as
contemplated by clause (i)). Upon termination of this Agreement,  all rights and
obligations of the parties  hereunder,  other than rights and obligations  under
Sections  10.11,  this  Section  11.3,  and  Sections  15, 20, 21 and 23,  shall
terminate and the January  Investment  Agreement  shall be reinstated  and shall
continue  in full  force and effect as between  the  parties  thereto as if this
Agreement had not been entered into.

SECTION 12.       Further Assurances.
- ------------------------------------

     At any time or from time to time after the First Closing,  the parties will
cooperate with each other, and at the request of another party,  each party will
execute  and  deliver any further  instruments  or  documents  and take all such
further action as the other party may reasonably request in order to evidence or
effectuate  the  consummation  of the  transactions  contemplated  hereby and to
otherwise carry out the intent of the parties hereunder.

SECTION 13.       Successors and Assigns.
- ----------------------------------------

     This  Agreement  shall bind and inure to the benefit of the parties and the
respective successors,  permitted assigns,  heirs and personal  representatives,
except that none of Parent,  Newco or TMI may assign its rights and  obligations
under this  Agreement  to any person  without the prior  written  consent of the
Investors. In addition, and whether or not any express assignment has been made,
the  provisions  of this  Agreement  that are for each  Investor's  benefit as a
purchaser or holder of Investor  Interests or Parent Common Stock or Convertible
Notes or Conversion  Interests are also for the benefit of, and  enforceable by,
any  subsequent  holder of such  Investor  Interests  or Parent  Common Stock or
Convertible Notes or Conversion Interests. An Investor may assign its rights and
obligations hereunder to any affiliate or to any of its stockholders, members or
partners,  or to any other party to this Agreement.  Subject to the restrictions
contained  in Newco LLC's  Operating  Agreement  or the Newco LP  Agreement,  an
Investor may also assign its rights and  obligations  hereunder,  including  its
rights pursuant to Section 3 hereof, to any permitted transferee of its Investor
Interest;  provided  that such  transferee  agrees in writing to be bound by the
terms of this Agreement, including that the appropriate Investors Group Designee
holds the right to request a Parent  Conversion as to the Investor Interest held
by such transferee.

SECTION 14.       Entire Agreement.
- ----------------------------------

     This Agreement and the Ancillary Agreements and the other writings referred
to herein or  delivered  pursuant  hereto  which form a part hereof  contain the
entire agreement among the parties with respect to the subject matter hereof and
supersede all prior arrangements or understandings with respect thereto.

SECTION 15.       Notices.
- -------------------------

     All notices,  requests,  consents and other communications hereunder to any
party shall be deemed to be  sufficient  if  contained  in a written  instrument
delivered in person or sent by telecopy, nationally recognized overnight courier
or first class registered or certified mail, return receipt  requested,  postage
prepaid,  addressed  to such party at the  address set forth below or such other
address as may  hereafter  be  designated  in writing by such party to the other
parties:

                  (i)      If to Parent, Parent Sub, Newco LLC or Newco LP, to:

                           Motient Corporation
                           10802 Parkridge Boulevard
                           Reston, Virginia  20191-5416
                           Fax:  (703) 758-6134
                           Attention:  General Counsel

                           with a copy to:

                           Hogan & Hartson L.L.P.
                           8300 Greensboro Drive, Suite 1100
                           McLean, Virginia  22102
                           Fax:  (703) 610-6200

                           Attention:  Richard K.A. Becker, Esq.

                  (ii)     If to the Note Investors, to each of the Note
                           Investors at their addresses set forth on
                           Schedule III.

                           with a copy to:

                           Skadden, Arps, Slate, Meagher & Flom LLP
                           Four Times Square
                           New York, NY  10036
                           Fax:  (917) 777-2918
                           Attention:  Gregory A. Fernicola, Esq.

                  (iii)    If to the Second Closing Investors, to each of the
                           Investor Group Designees at their addresses set forth
                           on Schedule IV.

                           with a copy to:

                           Kirkpatrick & Lockhart LLP
                           1251 Avenue of the Americas
                           45th Floor
                           New York, NY  10020-1104
                           Fax:  (212) 536-3901
                           Attention:  William J. Phillips, Esq.

                  (iv)     If to TMI or TMI Sub, to:

                           TMI Communications Inc.
                           1601 Telesat Court
                           Gloucester, Ontario
                           KIB5P4
                           Attention:  Legal Department

                           with a copy to:

                           Salans Hertzfeld Heilbronn Christy & Viener
                           620 Fifth Avenue
                           New York, New York  10020
                           Attention:  Owen D. Kurtin, Esq.

     All such  notices,  requests,  consents and other  communications  shall be
deemed to have been given when received.

SECTION 16.       Amendments.
- ----------------------------

     The terms and provisions of this  Agreement may be modified or amended,  or
any of the provisions hereof waived, temporarily or permanently, pursuant to the
written  consent  of  Parent,  TMI,  and on  behalf  of each  Investor,  by such
Investor's  Investor Group Designee.  No waiver of any of the provisions of this
agreement shall be deemed to or shall constitute a waiver of any other provision
hereof (whether or not similar). No delay on the part of any party in exercising
any right, power or privilege  hereunder shall operate as a waiver thereof.  The
covenants  contained  herein  relating to operations of Newco LP after the First
Closing  may be amended  with the  written  consent of persons  holding at least
50.1% of the limited partnership interests (in the case of the Note Investors on
an as converted  basis) in Newco LP,  provided that if any such amendment  would
have a materially  disproportionate effect on any party, such party's consent to
such  amendment  shall  also  be  required.  For  example  (and  not  by  way of
limitation),  an  amendment  to or waiver of any of the  covenants  contained in
Section  2.5  hereof  shall be  deemed to have a  materially  disproportionately
effect on the Existing Investors.

SECTION 17.       Counterparts.
- ------------------------------

     This Agreement may be executed in any number of counterparts, and each such
counterpart  hereof shall be deemed to be an original  instrument,  but all such
counterparts together shall constitute but one agreement.

SECTION 18.       Headings.
- --------------------------

     The  headings of the  sections of this  Agreement  have been  inserted  for
convenience  of  reference  only and  shall  not be  deemed to be a part of this
Agreement.

SECTION 19.       Nouns and Pronouns.
- ------------------------------------

     Whenever the context may require,  any pronouns  used herein shall  include
the corresponding masculine,  feminine or neuter forms, and the singular form of
names and pronouns shall include the plural and vice versa.

SECTION 20.       Governing Law.
- -------------------------------

     This Agreement is being executed and delivered in, and shall be governed by
and  construed in  accordance  with the laws of, the State of New York,  without
regard to its  principles  of  conflicts  of law that would  give  effect to the
application  of the law of  another  jurisdiction.  Each of the  parties  hereto
hereby irrevocably and  unconditionally  consents to submit to the non-exclusive
jurisdiction  of the courts of the State of New York and of the United States of
America,  in each case having  jurisdiction over the County of New York, for any
litigation  arising  out of or  relating  to this  Agreement  and the  Ancillary
Agreements and the transactions  contemplated hereby and thereby (and agrees not
to commence any  litigation  relating  thereto except in such courts unless such
courts shall have declined to exercise  jurisdiction),  and further  agrees that
service of any process,  summons,  notice or document by U.S. registered mail to
its respective address set forth in this Agreement shall be effective service of
process for any  litigation  brought  against it in any such court.  Each of the
parties hereto hereby  irrevocably and  unconditionally  waives any objection to
the  laying of venue of any  litigation  arising  out of this  Agreement  or the
transactions  contemplated  hereby in the courts of the State of New York or the
United States of America,  in each case having  jurisdiction  over the County of
New York, and hereby further irrevocably and  unconditionally  waives and agrees
not to plead or claim in any such court that any such litigation  brought in any
such court has been brought in an inconvenient or improper forum .

SECTION 21.       Publicity.
- ---------------------------

     (a) Except as may be required by applicable  law,  stock  exchange rules or
listing  agreements,  each of the  parties  hereto  agrees  that it will make no
public  statement  regarding  the  transactions  contemplated  hereby unless the
language and timing of such  statement has been approved by Parent,  TMI and the
Investor Group Designees.  Each Party acknowledges that it has received or shall
receive confidential and proprietary information concerning the assets, business
plans,  intellectual  property  rights and  operations  of Newco and the Related
Entities ("Confidential  Information").  Each party agrees that the Confidential
Information  is a valuable  asset of Newco or its owner,  as the case may be and
its public  disclosure  or use outside of Newco's  activities  without the prior
consent of Newco would cause  substantial harm to Newco.  Therefore,  each party
agrees to treat all Confidential  Information  received by it with the amount of
care that a reasonable business person would use to protect its own valuable and
proprietary  confidential  information  and shall not disclose any  Confidential
Information to any Person who does not have a contractual  obligation with Newco
to keep such Confidential Information confidential or does not have the right to
have such  Confidential  Information  disclosed  to it under an  agreement  with
Newco. In addition, each party shall not personally,  and shall not permit other
Persons (including its Affiliates) to utilize  Confidential  information for any
purpose other than for the benefit of Newco.

     (b)  Notwithstanding  the  foregoing,  a party  may  disclose  Confidential
Information to its affiliates,  professional advisors,  lenders and investors if
either (i) such Persons have agreed for the benefit of Newco, to comply with the
provision of this Section 21 or (ii) the disclosing party agrees for the benefit
of Newco and the other parties  hereto to be  responsible  for any breach by any
such Person.

     (c)  As  used  herein,   "Confidential   Information"   shall  not  include
information  (i) that has become  generally  available to the public  through no
fault of the receiving Person,  (ii) to the minimum extent necessary in order to
comply with any law, order,  regulation,  ruling or other  governmental  request
pursuant to subpoena or government order, provided that in the event a receiving
person is subject to such a subpoena or order,  it shall notify in writing Newco
of such event,  and shall  cooperate with any  reasonable  request or efforts by
Newco to take  reasonable  legally  permissible  actions  to limit  the scope of
disclosure  required in order for such  Person to comply  with such  subpoena or
order and (iii) as may be  required  or  appropriate  in response to any report,
statement or testimony submitted to any municipal,  state or national (including
foreign  regulatory  body  having or  claiming  to have  jurisdiction  over such
Person.

SECTION 22.       Severability.
- ------------------------------

     Whenever possible, each provision of this Agreement shall be interpreted in
such manner as to be effective and valid, but if any provision of this Agreement
is held to be  invalid or  unenforceable  in any  respect,  such  invalidity  or
unenforceability  shall not render invalid or unenforceable  any other provision
of this Agreement.

SECTION 23.       Expenses.
- --------------------------

     Except as  otherwise  set forth in this  Agreement,  Newco LP shall pay all
costs and expenses  reasonably  incurred by (i) the Existing  Investors (up to a
maximum of US$150,000),  (ii) Parent (up to a maximum of US$150,000),  (iii) TMI
(up to a maximum of  US$150,000),  (iii) the Lead Note Investor (up to a maximum
of  US$150,000),  and (iv)  Newco  LLC and  Newco  LP,  in  connection  with the
preparation,  negotiation  and  execution of this  Agreement  and the  Ancillary
Agreements and in connection with the closing of the  transactions  contemplated
hereby and thereby  (including  reasonable  legal fees incurred in preparing HSR
filings  and HSR  filing  fees)  except  for  expenses  relating  to any  Parent
Conversion,  which shall be paid by the Existing  Investors  electing to cause a
Parent  Conversion.  Such  payments  shall be made at the First Closing (or upon
termination  of  this  Agreement  if  the  First  Closing  shall  not  occur  as
contemplated  hereby) with respect to costs and expenses  incurred  through such
time,  and at the Second  Closing  (or upon  termination  of the  provisions  of
Section 2 hereof) with respect to costs and expenses incurred through such time.

SECTION 24.       Certain Defined Terms.
- ---------------------------------------

     "Additional Interests" has the meaning set forth in Section 5.1(a).

     "Affiliate"  means with  respect to a  specified  Person,  any Person  that
directly or indirectly  controls,  is controlled  by, or is under common control
with, the specified Person. As used in this definition, the term "control" means
the  possession,  directly  or  indirectly,  of the power to direct or cause the
direction of the management and policies of a Person,  whether through ownership
of voting securities, by contract or otherwise.

     "Amended  and  Restated  Sub Asset Sale  Agreement"  means the  Amended and
Restated  Sub Asset Sale  Agreement  dated as of January 8, 2001 between Sub and
Newco LLC.

     "Ancillary Agreements" means the agreements listed on Schedule VI.

     "Applications" has the meaning set forth in Section 4.15(b).

     "Appraisal Notice" has the meaning set forth in Section 7(a).

     "Appraiser" has the meaning set forth in Section 7(c).

     "Asset  Sale  Agreements"  means the Amended  and  Restated  Sub Asset Sale
Agreement and the TMI Asset Sale  Agreements,  in each case, as in effect on the
date  hereof,  and  without  giving  effect  to  any  amendment,   modification,
supplement, or restatement thereto or waiver thereunder.

     "BCE" has the meaning set forth in the preamble to this Agreement.

     "Canadian   Communications   Statutes"  means  the  Telecommunications  Act
(Canada), the Canadian  Radio-television and  Telecommunications  Commission Act
(Canada),  the  Radiocommunication  Act  (Canada),  or other  statutes of Canada
specifically  relating  to the  regulation  of the  Canadian  telecommunications
industry (including for this purpose the orders, rules, regulations, directives,
decisions, notices and policies promulgated pursuant to such statutes, including
the Radio Regulations,  the Canadian Telecommunications Common Carrier Ownership
and Control Regulations,  and applicable statutes or regulations, if any, of any
province of Canada  specifically  relating  to the  regulation  of the  Canadian
telecommunications  industry  and the orders,  rules,  regulations,  directives,
decisions, notices and policies promulgated thereunder.

     "Canadian  Holdco" shall mean Mobile Satellite  Ventures  Holdings (Canada)
Inc., an Ontario Corporation.

     "Canadian License Co." shall mean Mobile Satellite  Ventures (Canada) Inc.,
an Ontario Corporation.

     "Canadian License Co. Licenses" means the licenses  transferred to Canadian
License Co. pursuant to TMI Asset Sale Agreements.

     "Capital  Lease  Obligations"  means all monetary  obligations  of a Person
under any leasing or similar  arrangement  which,  in  accordance  with GAAP, is
required to be classified as a capital lease.

     "Cash  Equivalents"  means:  (i) securities  issued or fully  guaranteed or
insured by the United States  Government or any agency thereof and backed by the
full faith and credit of the United  States  having  maturities of not more than
twelve months from the date of acquisition;  (ii) certificates of deposit,  time
deposits,  Eurodollar time deposits, or banker's acceptances having in each case
a tenor of not more than six months,  issued by any U.S.  commercial bank having
combined  capital  and  surplus of not less than  $500,000,000  whose short term
securities are rated both A-1 or higher by Standard & Poor's Corporation and P-1
or higher by Moody's  Investors  Services,  Inc.;  (iii)  commercial paper of an
issuer rated either at least A-1 by Standard & Poor's  Ratings Group, a division
of McGraw-Hill,  Inc. and/or P-1 by Moody's Investors Service Inc. and in either
case having a tenor of not more than three months;  (iv)  repurchase  agreements
fully collateralized by securities issued by U.S. government  agencies;  and (v)
money market mutual funds invested in the instruments  permitted by clauses (i),
(ii), (iii) and (iv) above.

     "Claim Notice" has the meaning set forth in Section 10.11(g)(i).

     "Class A Preferred  Units"  shall have the  meaning  given such term in the
Newco LP Agreement.

     "Closing Price" has the meaning set forth in Section 3.1(b).

     "Code" has the meaning set forth in Section 8.12.

     "Commitment" has the meaning set forth in Section 4.7.

     "Confidential Information" has the meaning set forth in Section 21 hereof.

     "Contingent  Obligation"  means,  as applied to any  Person,  any direct or
indirect  liability  of that Person with respect to any Debt,  lease,  dividend,
letter of credit or other  obligation  (the  "primary  obligations")  of another
Person (the "primary obligor"), including, without limitation, any obligation of
that Person, whether or not contingent, (a) to purchase, repurchase or otherwise
acquire such primary obligations or any property constituting direct or indirect
security  therefor,  or (b) to advance or provide  funds (i) for the  payment or
discharge of any such primary obligation, or (ii) to maintain working capital or
equity capital of the primary  obligor or otherwise to maintain the net worth or
solvency or any balance  sheet item,  level of income or financial  condition of
the  primary  obligor,  or (c) to  purchase  property,  securities  or  services
primarily  for the purpose of assuring the owner of any such primary  obligation
of  the  ability  of the  primary  obligor  to  make  payment  of  such  primary
obligation,  or (d)  otherwise to assure or hold harmless the holder of any such
primary  obligation  against  loss in respect  thereof,  or (e) to  purchase  or
otherwise acquire,  or otherwise to assure a creditor against loss in respect of
any  Debt.  For  purposes  of this  definition,  the  amount  of any  Contingent
Obligation  shall be  deemed  to be an amount  equal to the  maximum  reasonably
anticipated liability in respect thereof.

     "Contract" has the meaning set forth in Section 4.8.

     "Conversion Certificate" has the meaning set forth in Section 1.6(b)(iii).

     "Conversion Notice" has the meaning set forth in Section 3.1(a).

     "Conversion Interests" has the meaning set forth in Section 4.4.

     "Convertible Notes" has the meaning set forth in Section 1.2(a).

     "Cross Licensing  Agreement" means the agreement  substantially in the form
attached hereto as Exhibit T.

     "CRTC"  shall mean the  Canadian  Radio-television  and  Telecommunications
Commission.

     "CRTC  Approval"  shall  mean  those  approvals  from  the CRTC  which  are
necessary  or  required to be  obtained  from the CRTC in order to transfer  any
international  telecommunications service provider licenses from TMI to Canadian
License Co.

     "Debt" means:  (i) all  indebtedness of Newco LP and its  Subsidiaries  for
borrowed  money,  including  borrowings of  commodities,  bankers'  acceptances,
letters of credit or letters of guarantee; (ii) all indebtedness of Newco LP and
its subsidiaries  for the deferred  purchase price of property or services other
than for goods and services  purchased  in the  ordinary  course of business and
paid for in accordance  with customary  practice and not  represented by a note,
bond,  debenture  or other  evidence  of  indebtedness;  (iii) all  indebtedness
created or arising under any conditional sale or other title retention agreement
with respect to property acquired by Newco LP and its subsidiaries  (even though
the rights and  remedies  of the seller or lender  under such  agreement  in the
event of default are limited to repossession or sale of such property); (iv) all
current  liabilities  of Newco LP and its  subsidiaries  represented  by a note,
bond,  debenture or other evidence of  indebtedness;  (v) all obligations  under
leases which have been or should be, in accordance  with U.S. GAAP,  recorded as
capital leases in respect of which Newco LP and its  subsidiaries  are liable as
lessee;  and (vi) all  indebtedness  of the kinds referred to in (i) through (v)
above  which  is  directly  or  indirectly   guaranteed  by  Newco  LP  and  its
subsidiaries or which Newco LP and its subsidiaries have agreed (contingently or
otherwise) to purchase or otherwise acquire, or in respect of which Newco LP and
its subsidiaries have otherwise assured a creditor or other Person against loss.

     "Document Standstill and Termination  Agreement" shall mean the Amended and
Restated  Document  Standstill and  Termination  Agreement of even date herewith
among Parent and the Existing  Investors,  as in effect on the date hereof,  and
without giving effect to any amendment, modification, supplement, or restatement
thereto or waiver thereunder.

     "Dollars" or "$" or "US$" means United States dollars.

     "DRULPA" has the meaning set forth in Section 1.1(a).

     "Encumbrances"  shall mean all  mortgages,  liens,  pledges,  encumbrances,
security  interests,  deeds  of  trust,  options,  encroachments,  reservations,
orders,  decrees,  judgments,  conditions,  restrictions,  charges,  agreements,
claims or equities of any kind.

     "Environmental Laws" has the meaning set forth in Section 8.22(a)(i).

     "ERISA" has the meaning set forth in Section 8.12.

     "Event of  Default"  has the  meaning  given  such term in the  Convertible
Notes.

     "Exchange Act" has the meaning set forth in Section 4.5(a).

     "Existing Investor" and "Existing  Investors" have the meaning set forth in
the opening paragraph of this Agreement.

     "Existing System Equipment Financing" means Debt, up to a maximum principal
amount of  US$4,000,000,  incurred by Newco LP for the purpose of enabling Newco
LP to acquire hardware or software,  to replace or upgrade hardware and software
owned by Newco LP as of the First  Closing  Date but only to the extent that the
proceeds of such Debt are applied to acquire such hardware or software.

     "Existing  Sub  Business" has the meaning set forth in the preamble to this
Agreement.

     "Existing  TMI  Business" has the meaning set forth in the preamble to this
Agreement.

     "Fair Market Value" has the meaning set forth in Section 7(b).

     "FCC" shall mean the United States Federal Communications Commission or any
successor  United  States  federal  agency or agencies with  responsibility  for
licensing the use of the radio frequency spectrum similar to that of the current
agency.

     "FCC Act" means the U.S. Communications Act of 1934, as amended.

     "FCC Applications" shall mean those two certain Applications filed with the
FCC:  one of which  was  filed by Sub and Newco  Sub,  in the form of  Exhibit Q
hereto,  requesting  authority  (1) to assign  Sub's FCC  licenses  and  pending
applications to Newco Sub (including  approval of foreign  ownership in Newco LP
and Newco GP of greater than 25 percent); (2) to modify those licenses to permit
Newco Sub to operate in a manner that is consistent  with the  Operations  Plan;
and (3) to launch and operate a  next-generation  satellite  system described in
said Application,  as said Application may be amended, modified, or supplemented
from time to time in  accordance  herewith;  the other of which was filed by TMI
and Newco Sub,  in the form of  Exhibit Q hereto,  requesting  authority  (1) to
assign  TMI's FCC  licenses  and  pending  applications  to Newco Sub and (2) to
modify  those  licenses  to permit  Newco  Sub to  operate  in a manner  that is
consistent with the Operations Plan.

     "FCC  Applications  Order"  shall  mean an  order  (or  orders)  of the FCC
granting in all material respects the FCC  Applications,  without the imposition
of any  conditions  that may  reasonably  be  expected  to result in a  Material
Adverse Effect on Newco or Canadian License Co.

     "FCC Change of Control  Approval"  shall mean an order or orders of the FCC
granting in all material  respects the requested  assignment of all material FCC
licenses from Sub and TMI to Newco Sub (including  approval of foreign ownership
in Newco LP and Newco GP of greater  than 25 percent)  and the  modification  of
those licenses sufficient to permit implementation of the Operations Plan.

     "FCC Other  Approvals"  shall  mean an order or orders of the FCC  granting
Newco  Sub in all  material  respects  the  authority  to launch  and  operate a
next-generation  satellite system as described in the FCC Applications,  as said
Application  may be  amended,  modified,  or  supplemented  from time to time in
accordance herewith.

     "Final FCC Order"  shall mean an order (or  orders) of the FCC  (including,
without  limitation,  the FCC  Applications  Order) with respect to which (a) no
request for a stay is pending,  no stay is in effect,  and any deadline that may
be designated by statute or regulation for filing such a request is passed;  (b)
no petition  for  rehearing  or  reconsideration  or  application  for review is
pending, and the time that may be designated by statute or regulation for filing
any such petition or application is passed;  (c) there is no  reconsideration by
the FCC on its own  motion  and the time that may be  designated  by  statute or
regulation for initiating any such reconsideration has passed; and (d) no appeal
is pending or in effect, and any deadline time that may be designated by statute
or regulation for filing any such appeal has passed.

     "Final Order Finality Date" has meaning set forth in Section 2.3(a).

     "First Closing" has the meaning set forth in Section 1.5(a).

     "First Closing Date" has the meaning set forth in Section 1.5(a).

     "First Closing Transactions" means the transactions contemplated hereby and
by the Ancillary Agreements which are to be consummated at the First Closing.

     "Flipper" has the meaning set forth in Section 7(a).

     "Flipper Sisters" has the meaning set forth in Section 7(a).

     "GAAP" means  generally  accepted  accounting  principles  set forth in the
opinions and pronouncements of the Accounting  Principles Board and the American
Institute of Certified Public  Accountants and statements and  pronouncements of
the Financial  Accounting Standards Board (or agencies with similar functions of
comparable stature and authority within the accounting  profession),  or in such
other  statements  by such other entity as may be in general use by  significant
segments  of  the  U.S.  accounting  profession,  which  are  applicable  to the
circumstances as of the date of determination.

     "Governmental Authority" means any nation or government, any state or other
political  subdivision  thereof,  any  central  bank  (or  similar  monetary  or
regulatory  authority) thereof,  any entity exercising  executive,  legislative,
judicial, regulatory or administrative functions of or pertaining to government,
and any  corporation  or other  entity  owned or  controlled,  through  stock or
capital ownership or otherwise, by any of the foregoing.

     "GTIS  Contract"  means  the GTIS  Bulk  Capacity  Lease  Agreement,  dated
September  14,  1998,  between  TMI and Her Majesty the Queen in Right of Canada
(acting  through and  represented  by the  Minister of  Communications)  and the
Operating Agreement,  dated April 3, 1996 between TMI and her Majesty the Queen,
as in effect on the date hereof,  and without  giving  effect to any  amendment,
modification, supplement, or restatement thereto or waiver thereunder

     "GTIS  Contract  Amendment"  means an  amendment  to the GTIS  Contract  as
contemplated by Exhibit N hereto.

     "Hazardous Material" has the meaning set forth in Section 8.22(a)(ii).

     "Holdings" has the meaning set forth in Section 4.8.

     "HSR Act" has the meaning set forth in Section 1.6(b)(xiii).

     "Indemnified Party" has the meaning set forth in Section 10.11(g)(i).

     "Indemnifying Party" has the meaning set forth in Section 10.11(g)(i).

     "Indenture" has the meaning set forth in Section 4.8.

     "Industry Canada" shall mean the Canadian Federal Department of Industry.

     "Industry  Canada  Application"  shall mean that certain  Application to be
filed  with the  Industry  Canada  by TMI,  in the  form of  Exhibit  S  hereto,
requesting  authority:  (1) to  assign to  Canadian  License  Co.  each of TMI's
existing Industry Canada licenses,  permits,  approvals and authorizations,  and
(2) to operate a next-generation satellite system described in said Application,
as said Application may be amended,  modified or supplemented  from time to time
in accordance herewith.

     "Industry  Canada  Application  Order"  shall  mean  those  authorizations,
licenses  and  approvals  which are  necessary  or required to be obtained  from
Industry Canada in order to grant approval to the Industry Canada Application.

     "Industry  Canada Approval" shall mean those  authorizations,  licenses and
approvals which are necessary or required to be obtained from Industry Canada in
order to grant approval to the Industry Canada Application.

     "Industry   Canada   Transfer  of  License   Approval"   shall  mean  those
authorizations, licenses and approvals of Industry Canada which are necessary to
grant,  in all  material  respects,  the  requested  assignment  of material TMI
licenses from TMI to Canadian License Co.

     "Interests" has the meaning set forth in Section 2.3(b).

     "Investment" means any investment in any Person,  whether by means of share
purchase,  capital contribution,  loan, Contingent  Obligation,  time deposit or
otherwise.

     "Investor"  and  "Investors"  have the  meaning  set  forth in the  opening
paragraph of this Agreement.

     "Investor Group" shall mean, with respect to any Investor,  such Investor's
Investor Group as identified on Schedule III or Schedule IV hereto,  as the case
may be.

     "Investor Group Designee" has the meaning set forth in Section 5.9(a).

     "Investor Interests" has the meaning set forth in Section 2.1.

     "Investor Purchase Price" has the meaning set forth in Section 2.1.

     "January  Agreements"  has the  meaning  set forth in the  preamble to this
Agreement.

     "January Investment Agreement" has the meaning set forth in the preamble to
this Agreement.

     "June  Agreements"  has the  meaning  set  forth  in the  preamble  to this
Agreement.

     "June  Investment  Agreement"  has the meaning set forth in the preamble to
this Agreement.

     "June  Transactions"  has the  meaning  set forth in the  preamble  to this
Agreement.

     "Lead Note Investor" has the meaning set forth in Section 1.6(b)(v).

     "Lead  Second  Closing  Investor"  has the  meaning  set  forth in  Section
2.3(b)(vii).

     "Licenses" has the meaning set forth in Section 4.15(a).

     "Lien"  means  any  mortgage,   deed  of  trust,   pledge,   hypothecation,
assignment,  charge or deposit  arrangement,  encumbrance,  lien  (statutory  or
other) or  preference,  priority  or other  security  interest  or  preferential
arrangement of any kind or nature  whatsoever  (including,  without  limitation,
those created by,  arising under or evidenced by any  conditional  sale or other
title  retention  agreement,  the  interest  of a lessor  under a Capital  Lease
Obligation, any financing lease having substantially the same economic effect as
any of the foregoing,  or the filing of any financing statement naming the owner
of the asset to which such lien relates as debtor,  under the Uniform Commercial
Code or any comparable law) and any contingent or other agreement to provide any
of the foregoing.  "Limited Partnership  Interests" has the meaning set forth in
the Newco LP Agreement.

     "Litigation" has the meaning set forth in Section 4.9.

     "Losses" has the meaning set forth in Section 10.11(b).

     "LP Certificate" has the meaning set forth in Section 1.6(b)(iii).

     "Market  Condition"  means  that,  as of any  date  and for each of the ten
trading days  immediately  preceding such date, (i) the NASDAQ  Composite  Index
closing  is not less  than  3300  (as  adjusted  equitably  for  changes  in the
calculation  of the NASDAQ  Composite  Index),  and (ii) the  closing  price for
Parent Common Stock is not less than $11.875 per share  (adjusted  equitably for
stock splits,  reverse stock splits, share combinations,  recapitalizations,  or
similar reorganizations of Parent Common Stock).

     "Material  Adverse  Effect"  shall  mean a material  adverse  effect on the
properties,  business, prospects,  operations,  earnings, assets, liabilities or
the condition (financial or otherwise) of the specified entity.  Notwithstanding
the foregoing,  the partial or complete  failure of the TMI Satellite shall not,
of itself,  be considered to have a Material  Adverse Effect on the Existing TMI
Business.

     "Motient  Communications"  means  Motient  Communications  Inc., a Delaware
corporation.

     "MSI Note" has the meaning set forth in Section 1.4(b).

     "New Investor" and "New Investors" has the meaning set forth in the opening
paragraph of this Agreement.

     "Newco" means (i) prior to the First Closing, Newco LLC, and (ii) after the
First Closing, Newco LP.

     "Newco  Financial  Statements"  has the  meaning  set forth in the  Section
10.7(b).

     "Newco GP" has the meaning set forth in Section 1.1(a).

     "Newco GP Stockholders  Agreement" means the agreement substantially in the
form attached hereto as Exhibit C.

     "Newco LLC" has the meaning in the opening paragraph of this Agreement.

     "Newco LLC Operating Agreement" means the Operating  Agreement,  dated June
29, 2000, by and between  Parent,  Newco LLC and the Existing  Investors,  as in
effect  on the  date  hereof,  and  without  giving  effect  to  any  amendment,
modification, supplement, or restatement thereto or waiver thereunder.

     "Newco LP" has the meaning set forth in the preamble to this Agreement.

     "Newco LP Agreement" has the meaning set forth in Section 1.1(a).

     "Newco LP  Disclosure  Schedule"  has the  meaning set forth in the opening
paragraph of Section 8.

     "Newco Rights" has the meaning set forth in Section 8.23.

     "Newco Securities" has the meaning set forth in Section 7(d).

     "Newco Sub" has the meaning set forth in Section 1.1(c).

     "Next Generation Financing" means Debt, up to a maximum principal amount of
US$5,000,000,  incurred by Newco LP for the purpose of enabling Newco LP to: (1)
acquire  hardware or software;  or (2) pay for legal,  regulatory  or consulting
costs directly related to the development of Newco LP's  next-generation  mobile
satellite system and its associated  terrestrial segment, but only to the extent
that the proceeds of such Debt are applied to acquire such hardware or software,
or to pay for such legal, regulatory and consulting costs.

     "Note Investors" has the meaning set forth in the opening paragraph of this
Agreement.

     "Note Securities" has the meaning set forth in Section 5.1(a).

     "Notice Closing Price" has the meaning set forth in Section 3.1(a).

     "Offer" has the meaning set forth in Section 7(f).

     "Operations Plan" has the meaning set forth in Section 10.9(a).

     "Original Purchase Price" has the meaning set forth in Section 3.1(a).

     "Ownership Regulations" has the meaning set forth in Section 6.12(d).

     "Parent" has the meaning in the opening paragraph of this Agreement.

     "Parent  Capital  Reorganization"  has the  meaning  set  forth in  Section
3.1(c).

     "Parent Common Stock" has the meaning set forth in Section 3.1(a).

     "Parent Conversions" has the meaning set forth in Section 3.1(a).

     "Parent Exchange" has the meaning set forth in Section 3.1(a).

     "Parent Interest" has the meaning set forth in Section 1.4(a).

     "Parent's  Loan  Agreements"  means the Term Credit  Agreement  dated as of
March 31, 1998 among Parent and the banks and other parties named  therein,  and
the Revolving Credit Agreement dated as of March 31, 1998 among Parent,  Sub and
the banks and other  parties  named  therein,  in each case, as in effect on the
date  hereof,  and  without  giving  effect  to  any  amendment,   modification,
supplement, or restatement thereto or waiver thereunder.

     "Parent Merger" has the meaning set forth in Section 3.1(a).

     "Parent/Newco Disclosure Schedule" has the meaning set forth in the opening
paragraph of Section 4.

     "Parent Reports" has the meaning set forth in Section 4.5(a).

     "Parent Securities" has the meaning set forth in Section 5.1(a).

     "Parent Sub" has the meaning set forth in Section 1.4(a).

     "Per Unit  Purchase  Price" means  $6.4465405156,  subject to adjustment in
accordance with Section 2.2.

     "Percentage Interests" has the meaning set forth in the Newco LP Agreement.

     "Permits" has the meaning set forth in Section 4.10.

     "Person"  means  any  individual,  corporation,   association,  partnership
(general or limited),  joint venture,  trust, estate, limited liability company,
or other legal entity or organization.

     "Pledge  Agreement" means the Pledge and Guaranty  Agreement in the form of
Exhibit X.

     "Pre-Funded Capital" shall have the meaning set forth in Section 2.1(b).

     "Pre-Funding Investor" shall have the meaning set forth in Section 2.1(b).

     "Proprietary Rights" has the meaning set forth in Section 8.23.

     "Public Authority" has the meaning set forth in Section 8.22(a)(iii).

     "Purchase Money  Indebtedness"  means any Debt incurred or assumed by Newco
LP to finance the cost (including the cost of  construction)  of an item of real
or personal property  (including the Existing System Equipment Financing and the
Next Generation  Financing) or the  improvement to such property,  the aggregate
principal  amount of which Debt does not exceed the sum of (i) 100% of such cost
and (ii)  reasonable  fees and  expenses  of Newco  LP  incurred  in  connection
therewith;  provided that such Debt is incurred or assumed within 90 days of the
acquisition of, or improvement to, such property.

     "Radiocommunication Act" has the meaning set forth in Section 6.12(g).

     "Radio Regulations" has the meaning set forth in Section 6.12(g).

     "Regulatory Disclosure" has the meaning set forth in Section 4.15(a).

     "Related Entities" means Canadian Holdco and Canadian License Co.

     "Sale" has the meaning set forth in Section 7(e).

     "SEC" has the meaning set forth in Section 4.5(a).

     "Second Closing" has the meaning set forth in Section 2.3(a).

     "Second Closing Date" has the meaning set forth in Section 2.3(a).

     "Second Closing Investors" has the meaning set forth in Section 2.1.

     "Securities Act" has the meaning set forth in Section 4.5(a).

     "Securities Laws" has the meaning set forth in Section 4.5(a).

     "Security Agreement" means the Security Agreement substantially in the form
of Exhibit W hereto.

     "Sub" has the meaning set forth in the preamble to this Agreement.

     "Sub Asset Sale  Agreement"  has the meaning  set forth in the  preamble to
this Agreement.

     "Subsidiary"  means,  as to any Person,  any corporation or other entity of
which  securities or other ownership  interests  having ordinary voting power to
elect a majority of the board of directors or other persons  performing  similar
functions are at the time directly or indirectly owned by such Person.

     "Telecommunications   Act  (Canada)"  means  the   Telecommunications   Act
(Canada), as amended.

     "TMI" has the meaning set forth in the opening paragraph of this Agreement.

     "TMI Applications" has the meaning set forth in Section 6.12(b).

     "TMI  Disclosure  Schedule"  has  the  meaning  set  forth  in the  opening
paragraph of Section 6.

     "TMI Interest" has the meaning set forth in Section 1.3(a)

     "TMI Licenses" has the meaning set forth in Section 6.12(a).

     "TMI Note" has the meaning set forth in Section 1.3(b).

     "TMI Sub" has the meaning set forth in Section 1.3(a).

     "TMI-Telesat  Letter  Agreement"  means the  agreement in the form attached
hereto as Exhibit Z.

     "TMI Asset Sale Agreements"  means the TMI-Newco Asset Sale Agreement,  the
TMI-Canadian  License  Co.  Asset  Sale  Agreement  and the  TMI-ULC  Asset Sale
Agreement,  in each case,  as in effect on the date hereof,  and without  giving
effect to any amendment,  modification,  supplement,  or restatement  thereto or
waiver thereunder.

     "TMI-Canadian  License  Co.  Asset  Sale  Agreement"  means the Asset  Sale
Agreement,  dated as of as of January 8,  2001,  as amended on the date  hereof,
between  Canadian  License  Co. and TMI,  as in effect on the date  hereof,  and
without giving effect to any further  amendment,  modification,  supplement,  or
restatement thereto or waiver thereunder.

     "TMI-Newco Asset Sale Agreement"  means the Asset Sale Agreement,  dated as
of as of January 8, 2001, as amended on the date hereof,  between Newco and TMI,
as in  effect on the date  hereof,  and  without  giving  effect to any  further
amendment,   modification,   supplement,   or  restatement   thereto  or  waiver
thereunder.

     "TMI-ULC Asset Sale  Agreement"  means the Asset Sale Agreement dated as of
as of January 8, 2001, as amended on the date hereof, between ULC and TMI, as in
effect on the date hereof,  and without giving effect to any further  amendment,
modification, supplement, or restatement thereto or waiver thereunder.

     "TMI  Satellite"  means the satellite  described in Schedule  2.3(a) of the
TMI-Canadian License Co. Asset Sale Agreement.

     "Transaction  Parties" shall mean the parties to this  Agreement,  TMI Sub,
Parent Sub, Canadian Holdco, Canadian License Co. and Newco LP, and "Transaction
Party" shall mean any of the foregoing.

     "ULC" means  3051361  Nova Scotia  ULC, a Nova Scotia  unlimited  liability
company.

     "Units" shall have the meaning set forth in the Newco LP Agreement.






     IN WITNESS WHEREOF, the parties hereto have duly executed this Agreement as
of the date first above written.

                              MOTIENT CORPORATION


                              By: /s/Gary M. Parsons
                                  ------------------
                              Name:  Gary M. Parsons
                              Title: Chairman

                              MOBILE SATELLITE VENTURES LLC


                              By: /s/Gary M. Parsons
                                  ------------------
                              Name:  Gary M. Parsons
                              Title: Chairman


                              TMI COMMUNICATIONS INC., for and on behalf of
                              TMI COMMUNICATIONS AND COMPANY LIMITED PARTNERSHIP


                              By: /s/Larry Boisvert
                                 -----------------------------------------------
                              Name:  Larry Boisvert
                              Title: President and CEO



                              By: /s/Ted Ignacy
                                 -----------------------------------------------
                              Name:  Ted Ignacy
                              Title: V.P. Finance





                                 NOTE INVESTORS:

                               MSV INVESTORS, LLC
                               By:  Rare Medium Group, Inc., its Managing Member


                               By: /s/Glenn S. Meyers
                                  ----------------------------------------------
                               Name: Chairman and Chief Executive Officer
                               Title: Glenn S. Meyers



                               EXISTING INVESTORS:
                               ------------------

                               COLUMBIA SPACE (QP), INC.


                               By: /s/James B. Fleming, Jr.
                                  ----------------------------------------------
                               Name: James B. Fleming, Jr.
                               Title: President

                               COLUMBIA SPACE (AI), INC.


                               By: /s/James B. Fleming, Jr.
                                  ----------------------------------------------
                               Name: James B. Fleming, Jr.
                               Title: President

                               COLUMBIA SPACE PARTNERS, INC.


                               By: /s/James B. Fleming, Jr.
                                  ----------------------------------------------
                               Name: James B. Fleming, Jr.
                               Title: President

                               NEW INVESTORS:
                               -------------

                               COLUMBIA SPACE (QP) II, INC.


                               By: /s/James B. Fleming, Jr.
                                  ----------------------------------------------
                               Name: James B. Fleming, Jr.
                               Title: President

                               COLUMBIA SPACE (AI) II, INC.


                               By: /s/James B. Fleming, Jr.
                                  ----------------------------------------------
                               Name: James B. Fleming, Jr.
                               Title: President

                               COLUMBIA SPACE PARTNERS II, INC.

                               By: /s/James B. Fleming, Jr.
                                  ----------------------------------------------
                               Name: James B. Fleming, Jr.
                               Title: President




                               EXISTING INVESTORS

                               SPECTRUM SPACE EQUITY
                               INVESTORS IV, INC.


                               By: /s/Kevin J. Maroni
                                  ----------------------------------------------
                                  Kevin J. Maroni
                                  Title:  Chairman and CEO

                               SPECTRUM SPACE IV PARALLEL, INC.


                               By: /s/Kevin J. Maroni
                                  ----------------------------------------------
                                  Kevin J. Maroni
                                  Title:  Chairman and CEO

                               SPECTRUM SPACE IV MANAGERS, INC.


                               By: /s/Kevin J. Maroni
                                  ----------------------------------------------
                                  Kevin J. Maroni
                                  Title:  Chairman and CEO





                                  NEW INVESTORS

                               SPECTRUM SPACE EQUITY
                               INVESTORS IV-II, INC.


                               By: /s/Kevin J. Maroni
                                  ----------------------------------------------
                                  Kevin J. Maroni
                                  Title:  Chairman and CEO

                               SPECTRUM SPACE IV PARALLEL II, INC.


                               By: /s/Kevin J. Maroni
                                  ----------------------------------------------
                                  Kevin J. Maroni
                                  Title:  Chairman and CEO

                               SPECTRUM SPACE IV MANAGERS II, INC.


                               By: /s/Kevin J. Maroni
                                  ----------------------------------------------
                                  Kevin J. Maroni
                                  Title:  Chairman and CEO

                                EXISTING INVESTOR

                               TELCOM SATELLITE VENTURES, INC.


                               By: /s/Kevin J. Maroni
                                  ----------------------------------------------
                                  Kevin J. Maroni
                                  Title:  Chairman and CEO

                                  NEW INVESTOR

                               TELCOM SATELLITE VENTURES II, INC.


                               By: /s/Kevin J. Maroni
                                  ----------------------------------------------
                                  Kevin J. Maroni
                                  Title:  Chairman and CEO





                                    SCHEDULES



Schedule I       -      Ownership of Newco LLC

Schedule II      -      Ownership of Newco LP Upon Conversion of Newco LLC

Schedule III     -      Convertible Notes To Be Purchased at First Closing

Schedule IV      -      Investor Interests To Be Purchased at Second Closing

Schedule V       -      Ownership of Newco LP Immediately After Second Closing

Schedule VI      -      Ancillary Agreements

Parent/Newco Disclosure Schedule

TMI Disclosure Schedule






                                    EXHIBITS

Exhibit A       Form of Newco GP Charter

Exhibit B       Form of Newco GP By-Laws

Exhibit C       Form of Newco GP Stockholders Agreement

Exhibit D       Form of Newco LP Limited Partnership Agreement

Exhibit E       Form of Convertible Note

Exhibit F       Form of US $11.5 Million Promissory Note (TMI)

Exhibit G       Form of US $15 Million Promissory Note (MSI)

Exhibit H       Form of Conversion Certificate and Form of Certificate of
                Limited Partnership

Exhibit I       Form of Merger Agreement

Exhibit J       Form of Capacity Lease

Exhibit K       Form of Rights and Services Agreement

Exhibit L       Form of Canadian Shareholders Agreement

Exhibit M       Omitted

Exhibit N       Memorandum of Understanding Describing Amendments to
                GTIS Contract

Exhibit O       Omitted

Exhibit P       Form of Guarantee

Exhibit Q       FCC Applications

Exhibit R       Operations Plan

Exhibit S       TMI Application to Industry Canada

Exhibit T       Form of Amended and Restated Cross-Licensing Agreement

Exhibit U       Form of Software License Agreement

Exhibit V       Form of Parent Transfer/Drag Along Letter

Exhibit W       Form of Security Agreement

Exhibit X       Form of Pledge and Guaranty Agreement

Exhibit Y       Form of Newco LP Agreement Addendum

Exhibit Z       Form of Newco GP Agreement Addendum






                                             SCHEDULE I

                               OWNERSHIP OF NEWCO LLC PRIOR TO CLOSING




- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------

                                                                        Number/          Percentage            Capital
            Name                             Address                 Type of Units         Interest          Contributions
            ----                             -------                 -------------         --------          -------------
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------

                                                                                                  
Motient                        10802 Parkridge Boulevard            80 Common Units         80.0%                $1.00
                               Reston, Virginia 20191-5416
                               Tel:  (703) 758-6130
                               Fax:  (703) 758-6134
                               Attention: General Counsel,

                               Hogan & Hartson L.L.P.
                               8300 Greensboro Drive
                               Suite 1100
                               McLean, Virginia  22102
                               Tel:  (703) 610-6123
                               Fax:  (703) 610-6200
                               Attention:  Richard K.A. Becker,
                               Esq.
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------

Telcom Satellite Ventures      211 North Union Street               7.2 Class A             7.20%             $18,000,000
Inc.                           Suite 300                            Preferred Units
                               Alexandria, Virginia 22314
                               Attention:  Hal B. Perkins
                               Tel:    (703) 706-3800
                               Fax:    (703) 706-3801
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------

Columbia Space (QP), Inc.      211 North Union Street               3.4504242 Class       3.4504242%          $8,626,061
                               Suite 300                            A Preferred
                               Alexandria, Virginia 22314           Units
                               Attention:  James Fleming
                               Tel:    (703) 519-3000
                               Fax:    (703) 519-3904
                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen Meredith, Esq.
                               Tel:  (617) 951-2233
                               Fax:  (888) 325-9120
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------

Columbia Space (AI), Inc.      211 North Union Street               0.19061125           0.19061125%           $476,528
                               Suite 300                            Class A
                               Alexandria, Virginia 22314           Preferred Units
                               Attention:  James Fleming
                               Tel:    (703) 519-3000
                               Fax:   (703) 519-3904
                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen Meredith, Esq.
                               Tel:    (617) 951-2233
                               Fax:   (888) 325-9120
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------

Columbia Space Partners, Inc.  211 North Union Street               2.75896456           2.75896456%          $6,897,411
                               Suite 300                            Class A
                               Alexandria, Virginia 22314           Preferred Units
                               Attention:  James Fleming
                               Tel:  (703) 519-3000
                               Fax:  (703) 519-3904
                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen
                               Meredith, Esq.
                               Tel:  (617) 951-2233
                               Fax:  (888) 325-9120
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
                               One International Place
Spectrum Space Equity          29th Floor                           6.18048 Class A        6.18048%           $15,451,200
Investors IV, Inc.             Boston, MA 82110                     Preferred Units
                               Attention:  Kevin Maroni
                               Tel:    (617) 464-4600
                               Fax:   (617) 464-4601
                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen
                               Meredith, Esq.
                               Tel:   (617) 951-2233
                               Fax:  (888) 325-9120
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------

Spectrum Space IV Parallel,    One International Place              0.14464 Class A       0.144640%            $361,600
Inc.                           29th Floor                           Preferred Units
                               Boston, MA 82110
                               Attention:  Kevin Maroni
                               Tel:    (617) 464-4600
                               Fax:   (617) 464-4601

                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen
                               Meredith, Esq.
                               Tel:   (617) 951-2233
                               Fax:  (888) 325-9120
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------

Spectrum Space IV Managers,    One International Place              0.07488 Class A       0.074880%            $187,200
Inc.                           29th Floor                           Preferred Units
                               Boston, MA 82110
                               Attention: Kevin Maroni
                               Tel:    (617) 464-4600
                               Fax:   (617) 464-4601

                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen
                               Meredith, Esq.
                               Tel:   (617) 951-2233
                               Fax:  (888) 325-9120
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------

Totals                                                              100 Units               100.0%          $50,000,001.00
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------












                                                SCHEDULE II

                              OWNERSHIP OF NEWCO LP UPON CONVERSION OF NEWCO LLC





- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------

                                                                        Number/          Percentage            Capital
            Name                             Address                 Type of Units         Interest          Contributions
            ----                             -------                 -------------         --------          -------------
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------

                                                                                                     
Motient Sub                    10802 Parkridge Boulevard            8,000,000             48.069032%             $1.00
                               -----------------------------------  Common Units
                               Reston, Virginia 20191-5416
                               Tel:  (703) 758-6130
                               Fax:  (703) 758-6134
                               Attention:  David Engvall, Vice
                               President and General Counsel

                               with a copy to:
                               Hogan & Hartson L.L.P.
                               8300 Greensboro Drive
                               Suite 1100
                               McLean, Virginia  22102
                               Tel:  (703) 610-6123
                               Fax:  (703) 610-6200
                               Attention:  Richard K.A. Becker,
                               Esq.
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------

Telcom Satellite Ventures      211 North Union Street               720,000 Class A       4.326213%           $18,000,000
Inc.                           Suite 300                            Preferred Units
                               Alexandria, Virginia 22314
                               Attention:  Hal B. Perkins
                               Tel:    (703) 706-3800
                               Fax:    (703) 706-3801
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------

Columbia Space (QP), Inc.      211 North Union Street               345,042.42            2.073232%           $8,626,061
                               Suite 300                            Class A
                               Alexandria, Virginia 22314           Preferred Units
                               Attention:  James Fleming
                               Tel:    (703) 519-3000
                               Fax:    (703) 519-3904
                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen Meredith, Esq.
                               Tel:  (617) 951-2233
                               Fax:  (888) 325-9120
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------

Columbia Space (AI), Inc.      211 North Union Street               19,061.12 Class       0.114531%            $476,528
                               Suite 300                            A Preferred
                               Alexandria, Virginia 22314           Units
                               Attention:  James Fleming
                               Tel:    (703) 519-3000
                               Fax:   (703) 519-3904
                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen Meredith, Esq.
                               Tel:    (617) 951-2233
                               Fax:   (888) 325-9120
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------

Columbia Space Partners, Inc.  211 North Union Street               275,896.46            1.657759%           $6,897,411
                               Suite 300                            Class A
                               Alexandria, Virginia 22314           Preferred Units
                               Attention:  James Fleming
                               Tel:  (703) 519-3000
                               Fax:  (703) 519-3904
                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen
                               Meredith, Esq.
                               Tel:  (617) 951-2233
                               Fax:  (888) 325-9120
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
                               One International Place
Spectrum Space Equity          29th Floor                           618,048.00            3.713621%           $15,451,200
Investors IV, Inc.             Boston, MA 82110                     Class A
                               Attention:  Kevin Maroni             Preferred Units
                               Tel:    (617) 464-4600
                               Fax:   (617) 464-4601
                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen
                               Meredith, Esq.
                               Tel:   (617) 951-2233
                               Fax:  (888) 325-9120
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------

Spectrum Space IV Parallel,    One International Place              14,464.00             0.086909%            $361,600
Inc.                           29th Floor                           Class A
                               Boston, MA 82110                     Preferred Units
                               Attention:  Kevin Maroni
                               Tel:    (617) 464-4600
                               Fax:   (617) 464-4601

                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen
                               Meredith, Esq.
                               Tel:   (617) 951-2233
                               Fax:  (888) 325-9120
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------

Spectrum Space IV Managers,    One International Place              7,488.00              0.044993%            $187,200
Inc.                           29th Floor                           Class A
                               Boston, MA 82110                     Preferred Units
                               Attention: Kevin Maroni
                               Tel:    (617) 464-4600
                               Fax:   (617) 464-4601

                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen
                               Meredith, Esq.
                               Tel:   (617) 951-2233
                               Fax:  (888) 325-9120
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
                                                                    6,636,481.51
TMI Sub                        1601 Telesat Court                   Common Units          39.876156%             $1.00
                               Gloucester Court
                               Canada K1B 1B9
                               Attn:  Rory McCormick

                               with a copy to:
                               Salans Hertzfeld Heilbronn Christy
                                 & Viener

                               Rockefeller Center
                               620 Fifth Avenue
                               New York, NY  10020-2457
                               Attn:  Owen D. Kurtin, Esq.
                               Tel:  (212) 623-8374
                               Fax: (212) 632-5555

- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------
                               8065 Leesburg Pike
Dean & Company                 Vienna, VA  22182                    6,250 Common          0.037554%              $1.00
                               Attention:  Dean Wilde, Chairman     Units


- ------------------------------ ------------------------------------ ----------------- ------------------- --------------------





                                                   SCHEDULE III



                   CONVERTIBLE NOTES TO BE PURCHASED AT THE FIRST CLOSING BY THE NOTE INVESTORS

                                                  NOTE INVESTORS

======================================== ========================= ============================= ===================================
                                           AGGREGATE PRINCIPAL
                                          AMOUNT OF CONVERTIBLE        NUMBER OF NOTES AND        NAME AND ADDRESS OF Investor group
           Name of investor               NOTES TO BE PURCHASED           DENOMINATIONS                         designee
           ----------------                           ---------           -------------                         --------
- ---------------------------------------- ------------------------- ----------------------------- -----------------------------------
- ---------------------------------------- ------------------------- ----------------------------- -----------------------------------
                                                                                           
                                         $50,000,000
NOTE INVESTOR GROUP 1:
                                                                                                 MSV Investors L.L.C.
                                                                                                 c/o Rare Medium Group, Inc.
MSV Investors, L.L.C.                                                                            28 West 23rd Street
                                                                                                 New York, New York 10010
                                                                                                 Attention:  General Counsel
Jurisdiction of                                                                                  Tel:    (646) 638-9600
Incorporation:  Delaware                                                                         Fax:    (646) 638-9716





- ---------------------------------------- ------------------------- ----------------------------- -----------------------------------
- ---------------------------------------- ------------------------- ----------------------------- -----------------------------------

                                                                                                 with a copy to:

                                                                                                 Skadden, Arps, Slate, Meagher &
                                                                                                 Flom LLP
                                                                                                 Four Time Square
                                                                                                 New York, NY 10036
                                                                                                 Attention:  Greg Fernicola
                                                                                                 Tel:    (212) 735-3000
                                                                                                 Fax:    (917) 777-2918
- ---------------------------------------- ------------------------- ----------------------------- -----------------------------------
- ---------------------------------------- ------------------------- ----------------------------- -----------------------------------
                                         $900,000
NOTE INVESTOR GROUP 2:
                                                                                                 Telcom Satellite Ventures Inc.
                                                                                                 211 North Union Street
Telcom Satellite Ventures II,                                                                    Suite 300
Inc.                                                                                             Alexandria, Virginia 22314
                                                                                                 Attention:  Hal B. Perkins
                                                                                                 Tel:    (703) 706-3800
                                                                                                 Fax:    (703) 706-3801

- ---------------------------------------- ------------------------- ----------------------------- -----------------------------------
- ---------------------------------------- ------------------------- ----------------------------- -----------------------------------
NOTE INVESTOR GROUP 3:                   $772,560                                                Spectrum Space Equity Investors IV,
                                                                                                 Inc.
                                                                                                 One International Place
Spectrum Space Equity                                                                            29th Floor
Investors IV-II, Inc.                                                                            Boston, MA 82110
                                                                                                 Attention:  Kevin Maroni
                                                                                                 Tel:    (617) 464-4600
                                                                                                 Fax:    (617) 464-4601
- ---------------------------------------- ------------------------- ----------------------------- -----------------------------------
- ---------------------------------------- ------------------------- ----------------------------- -----------------------------------
                                         18,080
Spectrum Space IV-II
Parallel, Inc.
- ---------------------------------------- ------------------------- ----------------------------- -----------------------------------
- ---------------------------------------- ------------------------- ----------------------------- -----------------------------------
                                         9,360
Spectrum Space IV-II                                                                             with a copy to:
Managers, Inc.
                                                                                                 Edwards & Angell, LLP
                                                                                                 101 Federal Street
                                                                                                 Boston, MA 02100
                                                                                                 Attention:  Stephen Meredith,
                                                                                                 Esq.
                                                                                                 Tel:    (617) 951-2233
                                                                                                 Fax:    (888) 325-9120
- ---------------------------------------- ------------------------- ----------------------------- -----------------------------------
- ---------------------------------------- ------------------------- ----------------------------- -----------------------------------

NOTE INVESTOR GROUP 4:                                                                           Columbia Space Partners, Inc.
                                                                                                 211 North Union Street
                                                                                                 Suite 300
Columbia Space (QP) II, Inc.             $431,303                                                Alexandria, Virginia 22314
                                                                                                 Attention:  James Fleming and Don
                                                                                                 Doering
                                                                                                 Tel:    (703) 519-3000
                                                                                                 Fax:    (703) 519-3904

- ---------------------------------------- ------------------------- ----------------------------- -----------------------------------
- ---------------------------------------- ------------------------- ----------------------------- -----------------------------------
                                         $23,826                                                 with a copy to:

Columbia Space (AI) II, Inc.                                                                     Edwards & Angell, LLP
                                                                                                 101 Federal Street
                                                                                                 Boston, MA 02100
                                                                                                 Attention:  Stephen Meredith,
                                                                                                 Esq.
                                                                                                 Tel:    (617) 951-2233
                                                                                                 Fax:    (888) 325-9120
- ---------------------------------------- ------------------------- ----------------------------- -----------------------------------
- ---------------------------------------- ------------------------- ----------------------------- -----------------------------------
Columbia Space Partners II,              $344,871
Inc.
- ---------------------------------------- ------------------------- ----------------------------- -----------------------------------









                                   SCHEDULE IV

                               EXISTING INVESTORS



======================================= =========================== =========================== ====================================
                                                                        purchase price for
                                            investor interests        INVESTOR INTERESTS to       NAME AND ADDRESS OF Investor group
           Name of investor                     Purchased                  be purchased                        designee
- --------------------------------------- --------------------------- --------------------------- ------------------------------------
- --------------------------------------- --------------------------- --------------------------- ------------------------------------

                                                                                       
INVESTOR GROUP 1:

Telcom Satellite Ventures,
Inc.
Jurisdiction of
Incorporation:  Delaware

                                        0.847900%                   US$1,800,000                Telcom Satellite
                                        (279,219.51                                             Ventures Inc.
                                        Class A                                                 211 North Union Street
                                        Preferred Units)                                        Suite 300
                                                                                                Alexandria, Virginia 22314
                                                                                                Attention:  Hal B. Perkins
                                                                                                Tel:    (703) 706-3800
                                                                                                Fax:    (703) 706-3801


- --------------------------------------- --------------------------- --------------------------- ------------------------------------
- --------------------------------------- --------------------------- --------------------------- ------------------------------------

INVESTOR GROUP 2:

Columbia Space (QP), Inc.
Jurisdiction of                                                     US$862,606
Incorporation:  Delaware
                                        0.406300%                                               Columbia Space
                                        (133,809.13                                             Partners, Inc.
                                        Class A                                                 211 North Union Street
                                        Preferred Units)                                        Suite 300
                                                                                                Alexandria, Virginia 22314
                                                                                                Attention:  James Fleming and Don
                                                                                                Doering
                                                                                                Tel:    (703) 519-3000
                                                                                                Fax:    (703) 519-3904
- --------------------------------------- --------------------------- --------------------------- ------------------------------------
- --------------------------------------- --------------------------- --------------------------- ------------------------------------
Columbia Space (AI), Inc.               0.022400%                   US$47,653                   with a copy to:
Jurisdiction of                         (7,392.00
Incorporation:  Delaware                Class A                                                 Edwards & Angell, LLP
                                        Preferred Units)                                        101 Federal Street
                                                                                                Boston, MA 02100
                                                                                                Attention:  Stephen Meredith,
                                                                                                Esq.
                                                                                                Tel:    (617) 951-2233
                                                                                                Fax:    (888) 325-9120
- --------------------------------------- --------------------------- --------------------------- ------------------------------------
- --------------------------------------- --------------------------- --------------------------- ------------------------------------
Columbia Space Partners, Inc.           0.324900%                   US$689,741
Jurisdiction of                         (106,993.99
Incorporation:  Delaware                Class A
                                        Preferred Units)
- --------------------------------------- --------------------------- --------------------------- ------------------------------------
- --------------------------------------- --------------------------- --------------------------- ------------------------------------
INVESTOR GROUP 3:

Spectrum Space Equity
Investors IV, Inc.
Jurisdiction of
Incorporation:  Delaware
                                        0.727800% (239,682.02       US$1,545,120
                                        Class A Preferred
                                        Units)
- --------------------------------------- --------------------------- --------------------------- ------------------------------------
- --------------------------------------- --------------------------- --------------------------- ------------------------------------
Spectrum Space IV Parallel,             0.017000%                   US$36,160
Inc.
                                        (5,609.21
Jurisdiction of                         Class A
Incorporation:  Delaware                Preferred Units)


- --------------------------------------- --------------------------- --------------------------- ------------------------------------
- --------------------------------------- --------------------------- --------------------------- ------------------------------------
Spectrum Space IV Managers,             0.008800%                   US$18,720
Inc.                                    (2,903.88
                                        Class A
Jurisdiction of                         Preferred Units)
Incorporation:  Delaware

- --------------------------------------- --------------------------- --------------------------- ------------------------------------
- --------------------------------------- --------------------------- --------------------------- ------------------------------------
Totals for Existing Investors                                       US$5,000,000
                                        2.355100%

                                        (775,609.74
                                        Class A
                                        Preferred Units)
======================================= =========================== =========================== ====================================







                                  NEW INVESTORS

======================================= =========================== =========================== ====================================
           Name of investor                 investor interests          purchase price for        NAME AND ADDRESS OF Investor group
           ----------------
                                                                      INVESTOR INTERESTS to
                                                Purchased                  be purchased                        designee
- --------------------------------------- --------------------------- --------------------------- ------------------------------------
- --------------------------------------- --------------------------- --------------------------- ------------------------------------

INVESTOR GROUP 1:

Telcom Satellite Ventures
II, Inc.
Jurisdiction of
Incorporation:  Delaware

                                        7.631100%                   US$16,200,000               Telcom Satellite
                                        (2,512,975.56                                           Ventures Inc.
                                        Class A                                                 211 North Union Street
                                        Preferred Units)                                        Suite 300
                                                                                                Alexandria, Virginia 22314
                                                                                                Attention:  Hal B. Perkins
                                                                                                Tel:    (703) 706-3800
                                                                                                Fax:    (703) 706-3801


- --------------------------------------- --------------------------- --------------------------- ------------------------------------
- --------------------------------------- --------------------------- --------------------------- ------------------------------------

INVESTOR GROUP 2:

Columbia Space (QP), II,                                                                        Columbia Space
Inc.                                    3.657000%                   US$7,763,455                Partners, Inc.
Jurisdiction of                         (1,204,282.18                                           211 North Union Street
Incorporation:  Delaware                Class A                                                 Suite 300
                                        Preferred Units)                                        Alexandria, Virginia 22314
                                                                                                Attention:  James Fleming and Don
                                                                                                Doering
                                                                                                Tel:    (703) 519-3000
                                                                                                Fax:    (703) 519-3904
- --------------------------------------- --------------------------- --------------------------- ------------------------------------
- --------------------------------------- --------------------------- --------------------------- ------------------------------------
Columbia Space (AI) II, Inc.            0.202000%                   US$428,875                  with a copy to:
Jurisdiction of                         (66,527.97
Incorporation:  Delaware                Class A                                                 Edwards & Angell, LLP
                                        Preferred Units)                                        101 Federal Street
                                                                                                Boston, MA 02100
                                                                                                Attention:  Stephen Meredith,
                                                                                                Esq.
                                                                                                Tel:    (617) 951-2233
                                                                                                Fax:    (888) 325-9120
- --------------------------------------- --------------------------- --------------------------- ------------------------------------
- --------------------------------------- --------------------------- --------------------------- ------------------------------------
Columbia Space Partners II,             2.924200%                   US$6,207,670
Inc.                                    (962,945.91
Jurisdiction of                         Class A
Incorporation:  Delaware                Preferred Units)
- --------------------------------------- --------------------------- --------------------------- ------------------------------------
- --------------------------------------- --------------------------- --------------------------- ------------------------------------
INVESTOR GROUP 3:

Spectrum Space Equity
Investors IV-II, Inc.
Jurisdiction of
Incorporation:  Delaware
                                        6.550600%                   US$13,906,080
                                        (2,157,138.22
                                        Class A Preferred
                                        Units)
- --------------------------------------- --------------------------- --------------------------- ------------------------------------
- --------------------------------------- --------------------------- --------------------------- ------------------------------------
Spectrum Space IV Parallel              0.153300%                   US$325,440
II, Inc.
                                        (50,482.89
Jurisdiction of                         Class A
Incorporation:  Delaware                Preferred Units)


- --------------------------------------- --------------------------- --------------------------- ------------------------------------
- --------------------------------------- --------------------------- --------------------------- ------------------------------------
Spectrum Space IV Managers              0.079400%                   US$168,480
II, Inc.                                (26,134.95
                                        Class A
Jurisdiction of                         Preferred Units)
Incorporation:  Delaware

- --------------------------------------- --------------------------- --------------------------- ------------------------------------
- --------------------------------------- --------------------------- --------------------------- ------------------------------------
Totals for New Investors                                            US$45,000,000
                                        21.197600%

                                        (6,980,487.68
                                        Class A
                                        Preferred Units)
======================================= =========================== =========================== ====================================











                                   SCHEDULE V

                 OWNERSHIP OF NEWCO LP FOLLOWING SECOND CLOSING



Parent                              8,387,804.87 units                 25.47%

Lead Note Investor                  7,756,097.42 units                 23.55%

Second Closing Investors            10,143,902.29units                 30.81%

TMI                                 6,636,481.51 units                 20.15%

Dean & Co.                          6,250.00 units                     0.02%

Total                               32,930,536.09 units                100%



Notes to schedule:

Motient includes initial 8,000,000 plus 387,804.87 units associated with $2.5
million note conversion.

Lead Note Investor includes $50.0 million of debt conversion.

Second Closing Investors includes units associated with initial $50 million
contribution, $2.5 million of note conversion, and $50 million from Second
Closing.



                                             SCHEDULE VI

                                        ANCILLARY AGREEMENTS

(1)      Newco LP Agreement

(2)      Newco GP Stockholders Agreement

(3)      Asset Sale Agreements

(4)      Telesat Preferred Provider Agreement

(5)      Canadian Shareholders Agreement

(6)      Capacity Lease Agreement

(7)      Amended and Restated Cross-Licensing Agreement

(8)      Amendment No. 2 to Research & Development Agreement

(9)      Rights and Services Agreement

(10)     Software License Agreement

(11)     Patent Assignment Agreement

(12)     TMI Note

(13)     MSI Note

(14)     TMI - Telesat Letter Agreement

(15)     Non-Interference Agreement

(16)     Telesat Management Services Agreement (Amendment)

(17)     Security Agreement

(18)     Guarantee

(19)     Pledge Agreement

(20)     Document Standstill and Termination Agreement

(21)     Parent Transfer/Drag Along Letter

(22)     Restoral Capacity Agreement

(23)     Amendment No. 2 to Registration Rights Agreement

(24)     Holdback Side Letter