EXHIBIT 10.39


                               MOTIENT CORPORATION


                          REGISTRATION RIGHTS AGREEMENT


         This REGISTRATION RIGHTS AGREEMENT (this "Agreement") is made as of
April 7, 2004 by and among (i) MOTIENT CORPORATION, a Delaware corporation, (the
"Company") (ii) The Raptor Global Portfolio, Ltd., The Tudor BVI Global
Portfolio, Ltd., The Altar Rock Fund L.P. and Tudor Proprietary Trading, L.L.C.
(collectively, the "Tudor Investors"), each of which is listed on Schedule 1
hereto, and (iii) each other investor listed on Schedule 1 hereto (each of the
persons or entities described in clauses (ii) and (iii), individually, an
"Investor" and, collectively, the "Investors").

         WHEREAS, the Company has agreed to issue and sell to the Investors, and
the Investors have agreed to purchase from the Company, an aggregate of
4,215,910 shares (the "Shares") of the Company's common stock, $0.01 par value
per share (including any securities into which or for which such shares may be
exchanged for, or converted into, pursuant to any stock dividend, stock split,
stock combination, recapitalization, reclassification, reorganization or other
similar event, the "Common Stock"), all upon the terms and conditions set forth
in the Common Stock Purchase Agreement, dated as of the date hereof, between the
Company and the Investors (the "Stock Purchase Agreement"); and

         WHEREAS, the terms of the Stock Purchase Agreement provide that it
shall be a condition precedent to the closing of the transactions thereunder,
for the Company and the Investors to execute and deliver this Agreement.

         NOW, THEREFORE, in consideration of the premises and mutual covenants
contained herein, the parties hereto hereby agree as follows:

         1. DEFINITIONS. The following terms shall have the meanings provided
therefor
below or elsewhere in this Agreement as described below:

         "Affiliates" means any Person that, directly or indirectly, through one
or more intermediaries, controls, is controlled by, or is under common control
with, a Person, as such terms are used and construed under Rule 144, and with
respect to the Tudor Investors, in addition to the foregoing, the term
"Affiliate" shall also include the Related Entities.

         "Board" means the board of directors of the Company.

         "Business Day" means any day except Saturday, Sunday and any day which
shall be a federal legal holiday or a day on which banking institutions in the
State of Delaware are authorized or required by law or other governmental action
to close.

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         "Closing Date" means the date on which the transactions contemplated by
the Stock Purchase Agreement are consummated.

         "Exchange Act" means the Securities Exchange Act of 1934, as amended,
and all of the rules and regulations promulgated thereunder.

         "Person" (whether or not capitalized) means an individual, partnership,
limited liability company, corporation, association, trust, joint venture,
unincorporated organization, and any government, governmental department or
agency or political subdivision thereof.

         "Prospectus" means the prospectus included in any Registration
Statement (including, without limitation, a prospectus that includes any
information previously omitted from a prospectus filed as part of an effective
Registration Statement in reliance upon Rule 430A promulgated under the
Securities Act), as amended or supplemented by any prospectus supplement, with
respect to the terms of the offering of any portion of the Registrable Shares
covered by such Registration Statement, and all other amendments and supplements
to the Prospectus, including post-effective amendments, and all material
incorporated by reference in such Prospectus.

         "Registrable Shares" means, at the relevant time of reference thereto,
the Shares and the Warrant Shares (including any shares of capital stock that
may be issued in respect thereof pursuant to a stock split, stock dividend,
recombination, reclassification or the like), provided, however, that the term
"Registrable Shares" shall not include any of the Shares or Warrant Shares that
are actually sold pursuant to a registration statement that has been declared
effective under the Securities Act by the SEC.

         "Registration Statement" means the Mandatory S-1 Registration
Statement, any Demand Registration on Form S-3, and any additional registration
statements contemplated by this Agreement, including (in each case) the
Prospectus, amendments and supplements to such registration statement or
Prospectus, including pre- and post-effective amendments, all exhibits thereto,
and all material incorporated by reference in such registration statement or
Prospectus.

         "Related Entities" includes, with respect to Tudor, any entities for
which any of the Tudor Entities or any its affiliates serve as general partner
and/or investment adviser or in a similar capacity, and all mutual funds or
other pooled investment vehicles or entities under the control or management of
any of the Tudor Entities or the general partner or investment adviser thereof,
or an any affiliate of any of them. For purposes of this Agreement, (a) "Tudor
Entities" means each of the following: any entity for which Tudor Investment
Corporation or an Affiliate thereof acts as general partner and/or investment
adviser, Tudor Investment Corporation, Tudor Group Holdings LLC, their
respective Affiliates, or any Affiliate or Affiliated Group of Tudor Investment
Corporation and/or Tudor Group Holdings LLC, and (b) with respect to the Tudor
Entities, "Affiliated Group" has the meaning given to it in Section 1504 of the
Internal Revenue Code of 1986, as amended, and in addition includes any
analogous combined, consolidated, or unitary group, as defined under any
applicable state, local or foreign income tax law.

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         "Rule 144" means Rule 144 promulgated under the Securities Act and any
successor or substitute rule, law or provision.

         "SEC" means the Securities and Exchange Commission.

         "Securities Act" means the Securities Act of 1933, as amended, and all
of the rules and regulations promulgated thereunder.

         "Warrants" means the warrants to purchase Common Stock, dated as of the
date hereof, issued by the Company to the Investors pursuant to the Stock
Purchase Agreement, a form of which is attached hereto as Exhibit A.

         "Warrant Shares" means the shares of Common Stock issued or issuable
upon the exercise of the Warrants.

         2. MANDATORY FORM S-1 REGISTRATION.

         (a) As promptly as possible after the date hereof, and in any event no
later than June 30, 2004 (the "Filing Date") the Company will prepare and file
with the SEC a registration statement on Form S-1 for the purpose of registering
under the Securities Act all of the Registrable Shares for resale by, and for
the account of, each Investor as an initial selling stockholder thereunder (the
"Mandatory S-1 Registration Statement"). The Mandatory S-1 Registration
Statement shall permit the Investors to offer and sell, on a delayed or
continuous basis pursuant to Rule 415 under the Securities Act, any or all of
the Registrable Shares. The Company agrees to use its best efforts to cause the
Mandatory S-1 Registration Statement to be declared effective as soon as
possible but in no event later than ninety (90) calendar days after the Filing
Date (the "Mandatory Effective Date") (including filing with the SEC, within
three (3) Business Days of the date that the Company is notified (orally or in
writing, whichever is earlier) by the SEC that the Mandatory S-1 Registration
Statement will not be "reviewed" or will not be subject to further review, a
request for acceleration of effectiveness in accordance with Rule 461
promulgated under the Securities Act (an "Acceleration Request"), which request
shall request an effective date that is within three (3) Business Days of the
date of such request). The Company shall notify each Investor in writing
promptly (and in any event within one (1) Business Day) after the Company's
submission of an Acceleration Request to the SEC. The Company shall be required
to keep the Mandatory S-1 Registration Statement continuously effective
(including through the filing of any required post-effective amendments) until
the earlier to occur of (i) the date after which all of the Registrable Shares
registered thereunder shall have been sold and (ii) the second (2nd) anniversary
of the later to occur of (a) the Mandatory Effective Date and (b) the date on
which each Warrant has either vested in full, or the date on which by the terms
of such Warrant there are no additional Warrant Shares with respect to which it
is possible for the Warrant to vest; provided, that in either case such date
shall be extended by the amount of time of any Suspension Period. Thereafter,
the Company shall be entitled to withdraw the Mandatory S-1 Registration
Statement and, upon such withdrawal, the Investors shall have no further right
to offer or sell any of the Registrable Shares pursuant to the Mandatory S-1
Registration Statement (or any Prospectus relating thereto).

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         (b) Notwithstanding anything in this Section 2 to the contrary, if the
Company shall furnish to the Investors a certificate signed by the President or
Chief Executive Officer of the Company stating that the Board has made the good
faith determination (i) that the continued use by the Investors of the Mandatory
S-1 Registration Statement for purposes of effecting offers or sales of
Registrable Shares pursuant hereto would require, under the Securities Act and
the rules and regulations promulgated thereunder, premature disclosure in the
Mandatory S-1 Registration Statement (or the Prospectus relating thereto) of
material, nonpublic information concerning the Company, its business or
prospects or any proposed material transaction involving the Company, (ii) that
such premature disclosure would be materially adverse to the Company, its
business or prospects or any such proposed material transaction or would not be
in the best interests of the Company and (iii) that it is therefore essential to
suspend the use by the Investors, of the Mandatory S-1 Registration Statement
(and the Prospectus relating thereto), then the right of the Investors to use
the Mandatory S-1 Registration Statement (and the Prospectus relating thereto)
for purposes of effecting offers or sales of Registrable Shares pursuant thereto
shall be suspended for a period (the "Suspension Period") not greater than
fifteen (15) consecutive Business Days during any consecutive twelve (12) month
period. During the Suspension Period, the Investors shall not offer or sell any
Registrable Shares pursuant to or in reliance upon the Mandatory S-1
Registration Statement (or the Prospectus relating thereto). The Company agrees
that, as promptly as possible, but in no event later than one (1) Business Day,
after the consummation, abandonment or public disclosure of the event or
transaction that caused the Company to suspend the use of the Mandatory S-1
Registration Statement (and the Prospectus relating thereto) pursuant to this
Section 2(c), the Company will as promptly as possible lift any suspension,
provide the Investors with revised Prospectuses, if required, and will notify
the Investors of their ability to effect offers or sales of Registrable Shares
pursuant to or in reliance upon the Mandatory S-1 Registration Statement.

         (c) It shall be a condition precedent to the obligations of the Company
to register Registrable Shares for the account of an Investor pursuant to this
Section 2 or Section 3 that such Investor furnish to the Company such
information regarding itself, the Registrable Securities held by it, and the
method of disposition of such securities as shall be required to effect the
registration of such Investor's Registrable Securities.

         (d) Notwithstanding anything in this Agreement to the contrary, the
Investors' sole remedy for the failure of the Company to file the Mandatory S-1
Registration Statement on or prior to June 30, 2004, shall be the vesting of the
Warrants as provided for therein.

         2A.      MANDATORY S-3 REGISTRATION RIGHTS

(a) If at any time any Registrable Shares are not able to be resold pursuant to
an effective Registration Statement, Form S-3 (or other equivalent form) is then
available for the registration of such Registrable Shares, and the Company shall
receive from any Investor (including for this purpose its Affiliates) who holds
(or who together hold) at least twenty-five percent (25%) of the then
outstanding Registrable Shares a written request or requests (a "Demand Notice")
that the Company effect a registration on Form S-3 (a "Demand Registration"), or


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any successor or substitute form, with respect to all or a part of the
Registrable Shares owned by such Investor(s), then the Company will promptly
give written notice of the proposed registration and the Investor's or
Investors' request therefor to all other Investors, and use best efforts to
effect such registration, as soon as practicable and in any event within thirty
(30) days, of all or such portion of such Investor's or Registrable Shares as
are specified in such request, together with all or such portion of the
Registrable Shares of any other Investor or Investors joining in such request as
are specified in a written request given within ten (10) business days after
receipt of such written notice from the Company; provided, however, that the
Company may temporarily suspended the use of such registration statement for the
same reasons and on the same terms as described in Section 2(b) above. The
Company shall not be required to effect more than three (3) registrations
pursuant to this Section 2A(a) during any consecutive twelve (12) month period.

         (b) It shall be a condition precedent to the obligations of the Company
to register Registrable Shares for the account of an Investor pursuant to this
Section 2 or Section 3 that such Investor furnish to the Company such
information regarding itself, the Registrable Securities held by it, and the
method of disposition of such securities as shall be required to effect the
registration of such Investor's Registrable Securities.

         3. "PIGGYBACK REGISTRATION".

         (a) If at any time any Registrable Shares are not able to be resold
pursuant to an effective Registration Statement, and the Company proposes to
register any of its Common Stock under the Securities Act, whether as a result
of an offering for its own account or the account of others (but excluding any
registrations to be effected on Forms S-4 or S-8 or other applicable successor
Forms), the Company shall, each such time, give to the Investors twenty (20)
days' prior written notice of its intent to do so, and such notice shall
describe the proposed registration and shall offer such Investors the
opportunity to register such number of Registrable Shares as each such Investor
may request. Upon the written request of any Investor given to the Company
within fifteen (15) days after the receipt of any such notice by the Company,
the Company shall include in such Registration Statement all or part of the
Registrable Shares of such Investor, to the extent requested to be registered.

         (b) If a registration pursuant to Section 3 hereof involves an
underwritten offering and the managing underwriter shall advise the Company in
writing that, in its opinion, the number of shares of Common Stock requested by
the Investors to be included in such registration is likely to affect materially
and adversely the success of the offering or the price that would be received
for any shares of Common Stock offered in such offering, then, notwithstanding
anything in this Section 3 to the contrary, the Company shall only be required
to include in such registration, to the extent of the number of shares of Common
Stock which the Company is so advised can be sold in such offering, (i) first,
the number of shares of Common Stock requested to be included in such
registration for the account of any stockholders of the Company (including the
Investors), pro rata among such stockholders on the basis of the number of
shares of Common Stock that each of them has requested to be included in such
registration, and (ii) second, any shares of Common Stock proposed to be
included in such registration for the account of the Company.

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         (c) In connection with any offering involving an underwriting of
shares, the Company shall not be required under this Section 3 or otherwise to
include the Registrable Shares of any Investor therein unless such Investor
accepts and agrees to the terms of the underwriting, which shall be reasonable
and customary, as agreed upon between the Company and the underwriters selected
by the Company.

         4. OBLIGATIONS OF THE COMPANY. In connection with the Company's
registration obligations hereunder, the Company shall, as expeditiously as
practicable:

         (a) No less than five (5) Business Days prior to filing, as required
hereunder, the Mandatory S-1 Registration Statement or Prospectus or any
amendments or supplements thereto (including any document that would be
incorporated or deemed to have been incorporated therein by reference (other
than documents containing material nonpublic information)), the Company shall
(i) furnish to each Investor and any counsel selected by the Investors holding a
majority of the Registrable Shares ("Investors' Counsel") copies of all such
documents to be filed with the SEC, which documents shall be subject to the
review of the Investors and Investors' Counsel, (ii) cause its officers and
directors, counsel and certified public accountants to respond to such inquiries
as shall be necessary, in the reasonable opinion of Investors' Counsel, to
conduct a reasonable investigation within the meaning of the Securities Act, and
(iii) notify the Investors and the Investors' Counsel of any stop order issued
or threatened by the SEC and use best efforts to prevent the entry of such stop
order or to remove it if entered. The Company shall not file the Mandatory S-1
Registration Statement, Prospectus or any amendments or supplements (other than
periodic reports required under the Exchange Act) thereto to which Investors
holding a majority of the Registrable Shares shall reasonably object to in
writing prior to filing; provided; however that the deadline set forth in
Section 2 hereof by which date the Mandatory S-1 Registration Statement is to be
filed shall be tolled during any period in which the Company and the Investors
address matters raised by the Investors in such written objection only if, and
for so long as, such objecting Investors consent in writing to such tolling.

         (b) Prepare and file with the SEC such amendments and supplements,
including post-effective amendments, to each Registration Statement and the
Prospectus used in connection therewith as may be necessary to keep the
Registration Statement continuously effective as required herein, and prepare
and file with the SEC such additional Registration Statements as necessary to
register for resale under the Securities Act all of the Registrable Shares
(including naming any permitted transferees of Registrable Shares as selling
stockholders in such Registration Statement); (ii) cause any related Prospectus
to be amended or supplemented by any required Prospectus supplement, and as so
supplemented or amended to be filed pursuant to Rule 424; (iii) respond as
promptly as possible to any comments received from the SEC with respect to each
Registration Statement or any amendment thereto and as promptly as possible
provide the Investors true and complete copies of all correspondence from and to
the SEC relating to the Registration Statement (other than correspondence
containing material nonpublic information); and (iv) comply with the provisions
of the Securities Act and the Exchange Act with respect to the disposition of
all Registrable Shares covered by such Registration Statement as so amended or
in such Prospectus as so supplemented.

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         (c) Notify the Investors and Investors' Counsel as promptly as possible
(i) when the SEC notifies the Company whether there will be a "review" of a
Registration Statement and whenever the SEC comments in writing on such
Registration Statement; and (ii) when a Registration Statement, or any
post-effective amendment or supplement thereto, has become effective, and after
the effectiveness thereof: (A) of any request by the SEC or any other federal or
state governmental authority for amendments or supplements to the Registration
Statement or Prospectus or for additional information; (B) of the issuance by
the SEC or any state securities commission of any stop order suspending the
effectiveness of the Registration Statement covering any or all of the
Registrable Shares or the initiation of any proceedings for that purpose; and
(C) of the receipt by the Company of any notification with respect to the
suspension of the qualification or exemption from qualification of any of the
Registrable Shares for sale in any jurisdiction, or the initiation or
threatening of any proceeding for such purpose. Without limitation of any
remedies to which the Investors may be entitled under this Agreement, if any of
the events described in Section 4(c)(ii)(A), 4(c)(ii)(B), and 4(c)(ii)(C) occur,
the Company shall use best efforts to respond to and correct the event.

         (d) Notify the Investors and Investors' Counsel as promptly as possible
of the happening of any event as a result of which the Prospectus included in or
relating to a Registration Statement contains an untrue statement of a material
fact or omits any fact necessary to make the statements therein not misleading;
and, thereafter, the Company will as promptly as possible prepare (and, when
completed, give notice to each Investor) a supplement or amendment to such
Prospectus so that, as thereafter delivered to the purchasers of such
Registrable Shares, such Prospectus will not contain an untrue statement of a
material fact or omit to state any fact necessary to make the statements therein
not misleading; provided that upon such notification by the Company, the
Investors will not offer or sell Registrable Shares until the Company has
notified the Investors that it has prepared a supplement or amendment to such
Prospectus and delivered copies of such supplement or amendment to the Investors
(it being understood and agreed by the Company that the foregoing proviso shall
in no way diminish or otherwise impair the Company's obligation to as promptly
as possible prepare a Prospectus amendment or supplement as above provided in
this Section 4(d) and deliver copies of same as above provided in Section 4(h)
hereof), and it being further understood that, in the case of the Mandatory S-1
Registration Statement, any such period during which the Investors are
restricted from offering or selling Registrable Shares shall constitute a
Suspension Period.

         (e) Upon the occurrence of any event described in Section 4(d) hereof,
as promptly as possible, prepare a supplement or amendment, including a
post-effective amendment, to the Registration Statement or a supplement to the
related Prospectus or any document incorporated or deemed to be incorporated
therein by reference, and file any other required document so that, as
thereafter delivered, neither the Registration Statement nor such Prospectus
will contain an untrue statement of a material fact or omit to state a material
fact required to be stated therein or necessary to make the statements therein,
in light of the circumstances under which they are made, not misleading.

         (f) Use best efforts to avoid the issuance of or, if issued, obtain the
withdrawal of, (i) any order suspending the effectiveness of any Registration


                                       7


Statement or (ii) any suspension of the qualification (or exemption from
qualification) of any of the Registrable Shares for sale in any jurisdiction, as
promptly as possible (it being understood that, in the case of the Mandatory S-1
Registration Statement, any period during which the effectiveness of the
Mandatory S-1 Registration Statement or the qualification of any Registrable
Shares is suspended shall constitute a Suspension Period).

         (g) Furnish to the Investors and Investors' Counsel, without charge, at
least one conformed copy of each Registration Statement and each amendment
thereto, and all exhibits to the extent requested by such Investor or Investors'
Counsel (including those previously furnished or incorporated by reference) as
promptly as possible after the filing of such documents with the SEC.

         (h) As promptly as possible furnish to each selling Investor, without
charge, such number of copies of a Prospectus, including a preliminary
Prospectus, in conformity with the requirements of the Securities Act, and such
other documents (including, without limitation, Prospectus amendments and
supplements) as each such selling Investor may reasonably request in order to
facilitate the disposition of the Registrable Shares covered by such Prospectus
and any amendment or supplement thereto. The Company hereby consents to the use
of such Prospectus and each amendment or supplement thereto by each of the
selling Investors in connection with the offering and sale of the Registrable
Shares covered by such Prospectus and any amendment or supplement thereto to the
extent permitted by federal and state securities laws and regulations.

         (i) Use best efforts to register and qualify (or obtain an exemption
from such registration and qualification) the Registrable Shares under such
other securities or blue sky laws of such jurisdictions as each Investor shall
request, to keep such registration or qualification (or exemption therefrom)
effective during the periods each Registration Statement is effective, and do
any and all other acts or things which may be reasonably necessary or advisable
to enable each Investor to consummate the public sale or other disposition of
Registrable Shares in such jurisdiction, provided that the Company shall not be
required in connection therewith or as a condition thereto to qualify to do
business or to file a general consent to service of process in any such states
or jurisdictions where it is not then qualified or subject to process.

         (j) Cooperate with the Investors to facilitate the timely preparation
and delivery of certificates representing the Registrable Shares to be delivered
to a transferee pursuant to a Registration Statement, which certificates shall
be free, to the extent permitted by the Stock Purchase Agreement and applicable
law, of all restrictive legends, and to enable such Registrable Shares to be in
such denominations and registered in such names as such Investors may request.

         (k) Cooperate with any reasonable due diligence investigation
undertaken by the Investors, any managing underwriter participating in any
disposition pursuant to a Registration Statement, Investors' Counsel and any
attorney, accountant or other agent retained by Investors or any managing
underwriter, in connection with the sale of the Registrable Shares, including,
without limitation, making available any documents and information; provided,
however, that the Company will not deliver or make available to any Investor


                                       8


material, nonpublic information unless such Investor specifically requests and
consents in advance in writing to receive such material, nonpublic information
and, if requested by the Company, such Investor agrees in writing to treat such
information as confidential.

         (l) At the request of an Affiliate, the Company shall amend any
Registration Statement to include such Affiliate as a selling stockholder in
such Registration Statement.

         (m) Comply with all applicable rules and regulations of the SEC in all
material respects.

         5. EXPENSES OF REGISTRATION. The Company shall pay for all expenses
incurred in connection with a registration pursuant to this Agreement and
compliance with Section 4 of this Agreement, including without limitation (i)
all registration, filing and qualification fees and expenses (including without
limitation those related to filings with the SEC, the Nasdaq National Market
System and in connection with applicable state securities or blue sky laws),
(ii) all printing expenses, (iii) all messenger, telephone and delivery expenses
incurred by the Company, (iv) all fees and disbursements of counsel for the
Company and Investors' Counsel, and (v) all fees and expenses of all other
Persons retained by the Company in connection with the consummation of the
transactions contemplated by this Agreement.

         6. DELAY OF REGISTRATION. Subject to Section 11(d) hereof, the
Investors and the Company (other than with respect to Section 4(d) hereof) shall
not take any action to restrain, enjoin or otherwise delay any registration as
the result of any controversy which might arise with respect to the
interpretation or implementation of this Agreement.

         7. INDEMNIFICATION. In the event that any Registrable Shares of the
Investors are included in a Registration Statement pursuant to this Agreement:

         (a) To the fullest extent permitted by law, the Company will indemnify
and hold harmless each Investor and each officer, director, fiduciary, agent,
investment advisor, employee, member (or other equity holder), general partner
and limited partner (and affiliates thereof) of such Investor, each broker or
other person acting on behalf of such Investor and each person, if any, who
controls such Investor within the meaning of the Securities Act, against any
losses, claims, damages or liabilities, joint or several, (the "Losses") to
which they may become subject under the Securities Act or otherwise, insofar as
such Losses (or actions in respect thereof) arise out of or relate to any untrue
or alleged untrue statement of any material fact contained in the Registration
Statement, or arise out of or relate to the omission or alleged omission to
state therein a material fact required to be stated therein, or necessary to
make the statements therein not misleading, or any violation by the Company of
the Securities Act or state securities or blue sky laws applicable to the
Company and leading to action or inaction required of the Company in connection
with such registration or qualification under such Securities Act or state
securities or blue sky laws; and, subject to the provisions of Section 7(c)
hereof, the Company will reimburse on demand such Investor, such broker or other
person acting on behalf of such Investor or such officer, director, fiduciary,
employee, member (or other equity holder), general partner, limited partner,
affiliate or controlling person for any legal or other expenses reasonably
incurred by any of them in connection with investigating or defending any such
loss, claim, damage, liability or action; provided, however, that the indemnity
agreement contained in this Section 7(a) shall not apply to amounts paid in


                                       9


settlement of any such Losses if such settlement is effected without the consent
of the Company (which consent shall not be unreasonably withheld), nor shall the
Company be liable in any such case for any such loss, damage, liability or
action to the extent that it solely arises out of or is based upon an untrue
statement of any material fact contained in the Registration Statement or
omission to state therein a material fact required to be stated therein or
necessary to make the statements therein not misleading, in each case to the
extent that such untrue statement or alleged untrue statement or omission or
alleged omission was made in the Registration Statement, in reliance upon and in
conformity with written information furnished by such Investor expressly for use
in connection with such Registration Statement.

         (b) To the fullest extent permitted by law, each Investor, severally
and not jointly, will indemnify and hold harmless the Company, each of its
directors, each of its officers who have signed the Registration Statement, each
person, if any, who controls the Company within the meaning of the Securities
Act, and all other Investors against any Losses to which the Company or any such
director, officer or controlling person or other Investor may become subject to,
under the Securities Act or otherwise, insofar as such Losses (or actions in
respect thereto) solely arise out of or are based upon any untrue statement of
any material fact contained in the Registration Statement, or solely arise out
of or relate to the omission to state therein a material fact required to be
stated therein or necessary to make the statements therein not misleading, in
each case to the extent that such untrue statement or alleged untrue statement
or omission or alleged omission was made in the Registration Statement in
reliance upon and in conformity with written information furnished by such
Investor expressly for use in connection with such Registration Statement; and,
subject to the provisions of Section 7(d) hereof, such Investor will reimburse
on demand any legal or other expenses reasonably incurred by the Company or any
such director, officer, controlling person, or other Investor in connection with
investigating or defending any such Losses, provided, however, that the maximum
amount of liability of such Investor hereunder shall be limited to the proceeds
(net of underwriting discounts and commissions, if any) actually received by
such Investor from the sale of Registrable Shares covered by such Registration
Statement; and provided, further, however, that the indemnity agreement
contained in this Section 7(b) shall not apply to amounts paid in settlement of
any such Losses if such settlement is effected without the consent of such
Investor against which the request for indemnity is being made (which consent
shall not be unreasonably withheld).

         (c) As promptly as possible after receipt by an indemnified party under
this Section 7 of notice of the threat, assertion or commencement of any action,
such indemnified party will, if a claim in respect thereof is to be made against
any indemnifying party under this Section 7, notify the indemnifying party in
writing of the commencement thereof and the indemnifying party shall have the
right to participate in and, to the extent the indemnifying party desires,
jointly with any other indemnifying party similarly noticed, to assume at its
expense the defense thereof with counsel mutually satisfactory to the parties;
provided, however, that, the failure to notify an indemnifying party promptly of


                                       10


the threat, assertion or commencement of any such action shall not relieve such
indemnifying party of any liability to the indemnified party under this Section
7 except (and only) to the extent that it shall be finally determined by a court
of competent jurisdiction (which determination is not subject to appeal or
further review) that such failure shall have proximately and materially
adversely prejudiced the indemnifying party.

         (d) If any indemnified party shall have reasonably concluded that there
may be one or more legal defenses available to such indemnified party which are
different from or additional to those available to the indemnifying party, or
that such claim or litigation involves or could have an effect upon matters
beyond the scope of the indemnity agreement provided in this Section 7, the
indemnifying party shall not have the right to assume the defense of such action
on behalf of such indemnified party, and such indemnifying party shall reimburse
such indemnified party and any person controlling such indemnified party for the
fees and expenses of counsel retained by the indemnified party which are
reasonably related to the matters covered by the indemnity agreement provided in
this Section 7. Subject to the foregoing, an indemnified party shall have the
right to employ separate counsel in any such action and to participate in the
defense thereof but the fees and expenses of such counsel shall not be at the
expense of the Company.

         (e) If the indemnification provided for in this Section 7 from the
indemnifying party is applicable by its terms but unavailable to an indemnified
party hereunder in respect of any Losses, then the indemnifying party, in lieu
of indemnifying such indemnified party, shall contribute to the amount paid or
payable by such indemnified party as a result of such losses, claims, damages,
liabilities or expenses in such proportion as is appropriate to reflect the
relative fault of the indemnifying party and indemnified party in connection
with the actions which resulted in such losses, claims, damages, liabilities or
expenses, as well as any other relevant equitable considerations. The relative
faults of such indemnifying party and indemnified party shall be determined by
reference to, among other things, whether any action in question, including any
untrue or alleged untrue statement of a material fact or omission or alleged
omission to state a material fact, has been made by, or relates to information
supplied by, such indemnifying party or indemnified party, and the parties'
relative intent, knowledge, access to information and opportunity to correct or
prevent such action. The amount paid or payable by a party as a result of the
losses, claims, damages, liabilities and expenses referred to above shall be
deemed to include, subject to the limitations set forth in Sections 7(a), 7(b)
7(c) and 7(d), any legal or other fees, charges or expenses reasonably incurred
by such party in connection with any investigation or proceeding. No person
guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of
the Securities Act) shall be entitled to contribution from any person. The
parties hereto agree that it would not be just and equitable if contribution
pursuant to this Section 7(e) were determined by pro rata allocation or by any
other method of allocation which does not take account of the equitable
considerations referred to in the immediately preceding paragraph.

         (f) The indemnity and contribution agreements contained in this Section
are in addition to any liability that any indemnifying party may have to any
indemnified party.

                                       11


         8. REPORTS UNDER THE EXCHANGE ACT. With a view to making available to
the Investors the benefits of Rule 144 and any other rule or regulation of the
SEC that may at any time permit the Investors to sell the Registrable Shares to
the public without registration, the Company agrees to use best efforts to: (i)
make and keep public information available, as those terms are understood and
defined in Rule 144, (ii) file with the SEC in a timely manner all reports and
other documents required to be filed by an issuer of securities registered under
the Securities Act or the Exchange Act; provided the parties hereto acknowledge
that such filings may not be made in a timely manner prior to June 30, 2004,
(iii) as long as any Investor owns any Shares or Warrant Shares, to furnish in
writing upon such Investor's request a written statement by the Company that it
has complied with the reporting requirements of Rule 144 and of the Securities
Act and the Exchange Act, and to furnish to such Investor a copy of the most
recent annual and quarterly reports of the Company, and such other reports and
documents so filed by the Company as may be reasonably requested in availing
such Investor of any rule or regulation of the SEC permitting the selling of any
such Shares without registration and (iv) undertake any additional actions
reasonably necessary to maintain the availability of a Registration Statement,
including any successor or substitute forms, or the use of Rule 144.

         9. TRANSFER OF REGISTRATION RIGHTS. Each Investor may assign or
transfer any or all of its rights under this Agreement to any Person, provided
such assignee or transferee agrees in writing to be bound by the provisions
hereof that apply to such assigning or transferring Investor. Upon any such, and
each successive, assignment or transfer to any permitted assignee or transferee
in accordance with the terms of this Section 9, such permitted assignee or
transferee shall be deemed to be an "Investor" (and a "Tudor Investor," as may
be appropriate) for all purposes of this Agreement.

         10. ENTIRE AGREEMENT. This Agreement constitutes and contains the
entire agreement and understanding of the parties with respect to the subject
matter hereof, and it also supersedes any and all prior negotiations,
correspondence, agreements or understandings with respect to the subject matter
hereof.

         11. MISCELLANEOUS.

         (a) This Agreement, and any right, term or provision contained herein,
may not be amended, modified or terminated, and no right, term or provision may
be waived, except with the written consent of (i) the holders of a majority of
the then outstanding Registrable Shares and (ii) the Company; provided that,
with respect to any right, term or provision relating to the Tudor Investors,
such right, term or provision shall not be amended, modified or terminated, and
no such right, term or provision shall be waived, except with the written
consent of (A) the Tudor Investors and (B) the Company.

         (b) This Agreement shall be governed by and construed and enforced in
accordance with the laws of the State of New York. This Agreement shall be
binding upon the parties hereto and their respective heirs, personal
representatives, successors and permitted assigns and transferees, provided that
the terms and conditions of Section 9 hereof are satisfied. Notwithstanding
anything in this Agreement to the contrary, if at any time any Investor
(including any successors or assigned) shall cease to own any Registrable
Shares, all of such Investor's rights under this Agreement shall immediately
terminate.

                                       12


         (c) Any notices to be given pursuant to this Agreement shall be in
writing and shall be given by certified or registered mail, return receipt
request. Notices shall be deemed given when personally delivered or when mailed
to the addresses of the respective parties as set forth on Exhibit A hereto, or
to such changed address of which any party may notify the others pursuant
hereto, except that a notice of change of address shall be deemed given when
received.

         (d) The parties acknowledge and agree that in the event of any breach
of this Agreement, remedies at law will be inadequate, and each of the parties
hereto shall be entitled to specific performance of the obligations of the other
parties hereto and to such appropriate injunctive relief as may be granted by a
court of competent jurisdiction. All remedies, either under this Agreement or by
law or otherwise afforded to any of the parties, shall be cumulative and not
alternative.

         (e) This Agreement may be executed in a number of counterparts. All
such counterparts together shall constitute one Agreement, and shall be binding
on all the parties hereto notwithstanding that all such parties have not signed
the same counterpart. The parties hereto confirm that any facsimile copy of
another party's executed counterpart of this Agreement (or its signature page
thereof) will be deemed to be an executed original thereof.

         (f) Except as contemplated in Section 9 hereof, this Agreement is
intended solely for the benefit of the parties hereto and is not intended to
confer any benefits upon, or create any rights in favor of, any Person
(including, without limitation, any stockholder or debt holder of the Company)
other than the parties hereto.

         (g) If any provision of this Agreement is invalid, illegal or
unenforceable, such provision shall be ineffective to the extent, but only to
the extent of, such invalidity, illegality or unenforceability, without
invalidating the remainder of such provision or the remaining provisions of this
Agreement, unless such a construction would be unreasonable.

         (h) This Agreement shall be binding upon, and inure to the benefit of,
the parties hereto and their permitted successors and assigns.



                           [signature pages to follow]









                                       13



         IN WITNESS WHEREOF, the parties hereto have executed this Registration
Rights Agreement as of the date and year first above written.


                                   MOTIENT CORPORATION



                                   By: /s/ Christopher Downie
                                       ----------------------------------------
                                   Name:   Christopher Downie
                                   Title:  Executive Vice President & CFO


                                   INVESTORS:


                                   THE RAPTOR GLOBAL PORTFOLIO LTD.
                                   By: Tudor Investment Corporation,
                                   Investment Advisors

                                   By: /s/ William T. Flaherty
                                       -----------------------------------------
                                   Name:   William T. Flaherty
                                   Title:  Managing Director


                                   THE TUDOR BVI GLOBAL PORTFOLIO, LTD.
                                   By: Tudor Investment Corporation,
                                   Trading Advisor

                                   By: /s/ William T. Flaherty
                                       -----------------------------------------
                                   Name:   William T. Flaherty
                                   Title:  Managing Director


                                   THE ALTAR ROCK FUND L.P.
                                   By: Tudor Investment Corporation,
                                   General Partner

                                   By: /s/ William T. Flaherty
                                       -----------------------------------------
                                   Name:   William T. Flaherty
                                   Title:  Managing Director


                                   TUDOR PROPRIETARY TRADING, L.L.C.


                                   By: /s/ William T. Flaherty
                                       -----------------------------------------
                                   Name:   William T. Flaherty
                                   Title:  Managing Director




                                       14




                                   HIGHLAND CRUSADER OFFSHORE PARTNERS, L.P.
                                   By: Highland Capital Management, L.P.
                                   As General Partner

                                   By: /s/ Todd Travers
                                       ----------------------------------------
                                   Name:   Todd Travers
                                   Title:  Senior Portfolio Manager


                                   YORK DISTRESSED OPPORTUNITIES FUND, L.P.


                                   By: /s/ Adam J. Semler
                                        ----------------------------------------
                                   Name:   Adam J. Semler
                                   Title:  CFO


                                   YORK SELECT, L.P.


                                   By: /s/ Adam J. Semler
                                       -----------------------------------------
                                   Name:   Adam J. Semler
                                   Title:  CFO


                                   YORK SELECT UNIT TRUST


                                   By: /s/ Adam J. Semler
                                       -----------------------------------------
                                   Name:   Adam J. Semler
                                   Title:  CFO


                                   M&E ADVISORS LLC


                                   By: /s/ Philip Mandelbaum
                                       -----------------------------------------
                                   Name:   Philip Mandelbaum
                                   Title:  CFO





                                       15




                                   CATALYST CREDIT OPPORTUNITY FUND
                                   By Catalyst Investment Management, LLC,
                                   its managing member

                                   By: /s/ Francis X. Gallagher
                                       -----------------------------------------
                                   Name:   Francis X. Gallagher
                                   Title:  Principal


                                   CATALYST CREDIT OPPORTUNITY FUND
                                   OFFSHORE
                                   By Catalyst Investment Management, LLC,
                                   its managing member

                                   By: /s/  Francis X. Gallagher
                                       -----------------------------------------
                                   Name:   Francis X. Gallagher
                                   Title:  Principal


                                   DCM LTD.
                                   By Catalyst Investment Management, LLC,
                                   its managing member

                                   By: /s/ Francis X. Gallagher
                                       -----------------------------------------
                                   Name:   Francis X. Gallagher
                                   Title:  Principal


                                   GREYWOLF CAPITAL II L.P.


                                   By: /s/ William Troy
                                       ----------------------------------------
                                   Name:   William Troy
                                   Title:  COO


                                   GREYWOLF CAPITAL OVERSEAS FUND


                                   By: /s/ William Troy
                                       -----------------------------------------
                                   Name:   William Troy
                                   Title:  COO






                                       16



                                   LC CAPITAL MASTER FUND


                                   By: /s/ Richard P. Conway
                                       -----------------------------------------
                                   Name:   Richard P. Conway
                                   Title:  Director






                                       17





                                                                       Exhibit A

                  All correspondence to the Company shall be addressed as
follows:

                           Motient Corporation
                           300 Knightsbridge Parkway
                           Lincolnshire, IL  60069
                           Attention:   Christopher Downie,
                                        Executive Vice President
                                        and Chief Financial Officer
                           Telecopier:  (847) 478-4810

                  with copies to:

                           Motient Corporation
                           300 Knightsbridge Parkway
                           Lincolnshire, IL  60069
                           Attention:   Robert Macklin, Esq.
                           Telecopier:  (847) 478-4810

                           Andrews Kurth LLP
                           450 Lexington Avenue
                           New York, NY  10017
                           Attention:   Paul Silverstein, Esq.
                           Telecopier:  (212) 850-2929

                  All correspondence to the Tudor Investors shall be addressed
                  as follows:

                           Tudor Investment Corporation
                           15303 Ventura Boulevard, Suite 900
                           Sherman Oaks, CA  91403
                           Attention:   Darryl L. Schall
                           Telecopier:  (818) 380-3065

                  with copies to:

                           Tudor Investment Corporation
                           1275 King Street
                           Greenwich, CT  06831
                           Attention:   Stephen N. Waldman, Esq.
                           Telecopier:  (203) 861-5144

                           Bingham McCutchen, LLP
                           150 Federal Street
                           Boston, Massachusetts 02110
                           Attention:   Victor J. Paci, Esq.
                                        Meerie M. Joung, Esq.
                           Telecopier:  (617) 951-8736




                                       18


                                   Schedule 1


                                List of Investors
                                -----------------



The Raptor Global Portfolio Ltd.

The Tudor BVI Global Portfolio, Ltd.

The Altar Rock Fund L.P.

Tudor Proprietary Trading, L.L.C.

Highland Crusader Offshore Partners, L.P.

York Distressed Opportunities Fund, L.P.

York Select, L.P.

York Select Unit Trust

M&E Advisors LLC

Catalyst Credit Opportunity Fund

Catalyst Credit Opportunity Fund Offshore

DCM, Ltd.

Greywolf Capital II L.P.

Greywolf Capital Overseas Fund

LC Capital Master Fund