EXHIBIT 10.43


                               MOTIENT CORPORATION

                          REGISTRATION RIGHTS AGREEMENT

This REGISTRATION RIGHTS AGREEMENT (this "Agreement") is made as of June 30,
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") and (iii) each investor listed on Schedule
1 hereto (each such investor, 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 3,500,000
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
Securities Purchase Agreement, dated as of the date hereof, between the Company
and the Investors (the "Securities Purchase Agreement"); and

WHEREAS, the terms of the Securities 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.

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

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"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.

"Related Entities" includes, with respect to the Tudor Investors, any entities
for which any of the Tudor Entities or any of its affiliates serve as general
partner and/or investment advisor 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 any affiliate 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 or any 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.

"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.

"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.

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"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 Securities
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 prior to
July 15, 2004, the Company shall include the Registrable Shares on the Mandatory
S-1 Registration Statement (as such term is defined in that certain Registration
Rights Agreement made as of April 7, 2004 by and among the Company and the other
parties thereto (as amended from time to time, the "Previous Registration Rights
Agreement")). The Mandatory S-1 Registration Statement shall be filed pursuant
to the terms of this Agreement and the Previous Registration Rights Agreement
and 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 the Mandatory Effective Date (as such term
is defined in the Previous Registration Rights Agreement) (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 (as such term is
defined in the Previous Registration Rights Agreement) 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 (as defined below).
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 as promptly as possible after the date hereof, and in any
event on or prior to July 15, 2004, or for the failure of the Company to make
effective the Mandatory S-1 Registration Statement on or prior to November 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
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


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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) (i) furnish to each Investor copies of all documents filed with the SEC
prior to their being filed with the SEC, (ii) use commercially reasonable
efforts to cause its officers and directors, counsel and certified public
accountants to respond to such inquiries as shall be necessary, in the
reasonable opinion of such Investor, to conduct a reasonable investigation
within the meaning of the Securities Act, and (iii) notify the Investors 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.

(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.

(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.

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(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
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


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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 Securities 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 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.

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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 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


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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
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,


                                       10
<PAGE>

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.

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
<PAGE>

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, and only 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.

(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.

                                       12
<PAGE>

(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
<PAGE>





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 & COO



                                  INVESTOR:


                        ----------------------------
                         [Name of Investor]




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





                                       14
<PAGE>




                                    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 Operating 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 Investors shall be addressed as set forth in Schedule
1 below




<PAGE>




                                   Schedule 1

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


Name and Address
----------------

Rockbay Capital Fund, LLC
600 Fifth Avenue
New York, NY  10020


Rockbay Capital Institutional Fund, LLC
600 Fifth Avenue
New York, NY  10020


Rockbay Capital Offshore Fund, Ltd.
600 Fifth Avenue
New York, NY  10020


Glenview Capital Partners, L.P.
399 Park Avenue
39th Floor
New York, NY  10022


Glenview Institutional Partners, L.P..
399 Park Avenue
39th Floor
New York, NY  10022


Glenview Capital Master Fund, Ltd..
399 Park Avenue
39th Floor
New York, NY  10022


GCM Little Arbor Master Fund, Ltd..
399 Park Avenue
39th Floor
New York, NY  10022

<PAGE>

OZ Master Fund, Ltd.
Goldman Sachs (Cayman) Trust, Limited
Harbour Center, 2nd Floor
George Town, Grand Cayman
Cayman Islands, B.W.I.


OZ Mac 13 Ltd.
Maples and Calder, Attorneys-at-law
Ugland House
P.O. Box 309, South Church Street
George Town
Grand Cayman, Cayman Islands


Fleet Maritime, Inc.
The International Trust Company of Liberia
80 Broad Street
City of Monrovia
Country of Monfserrado
Republic of Liberia


John Waterfall
600 Fifth Avenue, 27th Floor
New York, NY  10020


Edwin Morgens
600 Fifth Avenue, 27th Floor
New York, NY  10020


Strome Hedgecap Limited


Catalyst Credit Opportunity Fund Offshore
Attn:  Conifer Securities
One Ferry Building, Suite 255
San Francisco, CA  94111


Catalyst Credit Opportunity Fund
Attn:  Conifer Securities
One Ferry Building, Suite 255
San Francisco, CA  94111

<PAGE>

DCM Ltd.
Attn:  Conifer Securities
One Ferry Building, Suite 255
San Francisco, CA  94111


York Capital Management, L.P.
390 Park Avenue, 15th Floor
New York, NY  10022


York Investment Limited
390 Park Avenue, 15th Floor
New York, NY  10022


York Select, L.P.
c/o York Capital Management, L.P.
390 Park Avenue, 15th Floor
New York, NY  10022


York Select Unit Trust
c/o York Capital Management, L.P.
390 Park Avenue, 15th Floor
New York, NY  10022


York Distressed Opportunities Fund, L.P.
c/o York Capital Management, L.P.
390 Park Avenue, 15th Floor
New York, NY  10022
ID No.:  13-4153848

York Global Value Partner, L.P.
c/o York Capital Management, L.P.
390 Park Avenue, 15th Floor
New York, NY  10022


The Raptor Global Portfolio Ltd.

The Tudor BVI Global Portfolio Ltd.

Tudor Proprietary Trading, L.L.C.

The Altar Rock Fund L.P.

<PAGE>

LC Capital Master Fund, Ltd
680 Fifth Avenue
Suite 1202 New York, NY 10019 ID No.: 98-0374362

Singer Children's Management Trust
c/o Romulus Holdings, Inc.
560 Sylvan Avenue
Englewood Cliffs, NJ  07632
ID No.:  22-6765093



Greywolf Capital Partners II LP



Greywolf Capital Overseas Fund



Highland Equity Focus Fund, L.P.