Exhibit 10.1

EXECUTION

REGISTRATION RIGHTS AGREEMENT

This REGISTRATION RIGHTS AGREEMENT (this “Agreement”), dated as of September 25,
2006, is by and between Motient Corporation, a Delaware corporation (“Motient”),
and SkyTerra Communications, Inc., a Delaware corporation (“SkyTerra”). Certain
capitalized terms used herein are defined in Section 7 below. Capitalized terms
not otherwise defined herein have the meaning ascribed to them in the MSV
Exchange Agreement (as hereinafter defined).

RECITALS:

WHEREAS, Motient, MVH Holdings Inc., a Delaware corporation and wholly owned
subsidiary of Motient (“MVH”), and SkyTerra have entered into an Exchange
Agreement, dated as of May 6, 2006 (the “MSV Exchange Agreement”), that
provides, subject to the terms and conditions thereof, for the purchase by
SkyTerra of 100% of the limited partnership units (the “MSV LP Units”) of Mobile
Satellite Ventures, LP, a Delaware limited partnership (“MSV”) and common stock
of Mobile Satellite Ventures GP, Inc., a Delaware corporation and the general
partner of MSV (“MSV GP Shares”), held directly by MVH (the “MSV Exchange”);

WHEREAS, as part of the consideration to be paid in the MSV Exchange, SkyTerra
will issue an aggregate of 44,333,417 shares (the “Acquired Shares”) of
non-voting common stock, par value $0.01 per share of SkyTerra, exchangeable in
certain circumstances for an equal number of shares of common stock, par value
$0.01 per share, of SkyTerra (“Common Shares”) pursuant to Section 4.7 of the
MSV Exchange Agreement;

WHEREAS, in order to induce Motient to consummate the transactions under the MSV
Exchange Agreement, SkyTerra has agreed to provide certain registration rights
on the terms and subject to the conditions set forth herein; and

WHEREAS, it is a condition to the closing of the transactions under the MSV
Exchange Agreement that SkyTerra and Motient enter into this Agreement;

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

SECTION 1. REGISTRATION UNDER THE SECURITIES ACT.

1.1 Registration.

(a) As promptly as possible after the date hereof, and in any event prior to the
date that is ten (10) business days following the date hereof, SkyTerra shall
prepare and file with the Securities and Exchange Commission (the “SEC”) a
registration statement on the appropriate form for the purpose of registering
under the Securities Act 14,407,343 of the Common Shares (as appropriately
adjusted in accordance with the MSV Exchange Agreement) (the “Resale Shares”)
for resale by Motient (the “Resale Registration Statement”). SkyTerra agrees to
use its commercially reasonable efforts to cause the Resale Registration
Statement to be declared effective as soon as practicable after the filing
thereof with the SEC.

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(b) SkyTerra shall keep the Resale Registration Statement effective (including
through the filing of any required post-effective amendments) until the earlier
to occur of (i) such time as Motient has sold all of the Common Shares
registered thereunder or (ii) July 15, 2010; provided, that such date shall be
extended by the amount of time of any period during which Motient may not use
the Resale Registration Statement as the result of the occurrence of an event
described in Section 1.2(e) (ii), (iii) or (iv) below. Thereafter, SkyTerra
shall be entitled to withdraw the Resale Registration Statement and, upon such
withdrawal, Motient shall have no further right to sell any of the Common Shares
pursuant to the Resale Registration Statement (or any prospectus forming a part
thereof).

(c) Pursuant to Section 1.3(b)(ii) of the MSV Exchange Agreement, SkyTerra has
filed a registration statement on Form S-3 (File No. 333-135580) with the SEC
registering under the Securities Act 25,478,273 of the Common Shares (as
appropriately adjusted in accordance with the MSV Exchange Agreement) for
distribution by Motient as a dividend to the Motient Common Stockholders (the
“Distribution Registration Statement”). The Distribution Registration Statement
was declared effective by the SEC on September 22, 2006.

(d) Pursuant to Section 1.3(b)(iii) of the MSV Exchange Agreement, SkyTerra has
filed a registration statement on Form S-3 (File No. 333-135580) with the SEC
registering under the Securities Act 4,447,801 of the Common Shares (as
appropriately adjusted in accordance with the MSV Exchange Agreement) for
distribution by Motient to the holders of Motient’s Series A Cumulative
Convertible Preferred Stock and Series B Cumulative Convertible Preferred Stock
upon the election by the holders of such shares to convert such shares of
Motient preferred stock into shares of Motient Common Stock (the “Preferred
Registration Statement” and, together with the Distribution Registration
Statement and the Resale Registration Statement, the “Registration Statements”).
The Preferred Registration Statement was declared effective by the SEC on
September 22, 2006. The registrations effected pursuant to the Registration
Statements are referred to herein as the “Registrations.”

(e) SkyTerra shall keep the (i) Distribution Registration Statement effective
(including through the filing of any required post-effective amendments) until
such time as Motient declares and pays the dividend of the Common Shares to the
Motient Common Stockholders referenced in the Distribution Registration
Statement and (ii) Preferred Registration Statement effective (including through
the filing of any required post-effective amendments) until the earlier to occur
of (A) the date after which all of the Common Shares registered thereunder shall
have been distributed by Motient to its preferred stockholders and (B) July 15,
2010; provided, that such date shall be extended by the amount of time of any
period during which Motient may not use the Preferred Registration Statement as
the result of the occurrence of an event described in Section 1.2(e) (ii),
(iii) or (iv) below. Thereafter, SkyTerra shall be entitled to withdraw the
Distribution Registration Statement and the Preferred Registration Statement, as
applicable, and, upon such withdrawal, Motient shall have no further right to
distribute any of the Common Shares pursuant to the Distribution Registration
Statement or Preferred Registration Statement (or any prospectus forming a part
thereof), as applicable.

1.2 Registration Procedures. Subject to the terms and conditions hereof,
whenever any Common Shares are required to be registered pursuant to this
Agreement or were required to be registered pursuant to the MSV Exchange
Agreement, SkyTerra shall use its commercially

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reasonable efforts to effect the registration (if not previously effected) and
the sale or distribution of such Common Shares (if not previously sold or
distributed) in accordance with the intended method of disposition thereof, and
pursuant thereto SkyTerra shall as expeditiously as practicable:

 

  (a) promptly prepare and file with the SEC the applicable registration
statement with respect to such Common Shares (and any amendments, including any
post-effective amendments or supplements to such registration statement SkyTerra
deems to be necessary) and use its commercially reasonable efforts to cause such
registration statement to become effective and to comply with the provisions of
the Securities Act applicable to it; provided, that before filing a registration
statement or prospectus or any amendments or supplements thereto, SkyTerra shall
furnish to counsel for Motient copies of all such documents proposed to be
filed, including documents incorporated by reference in the registration
statement and, if requested by Motient, the exhibits incorporated by reference
so as to provide Motient and its counsel a reasonable opportunity to review and
comment on such documents, and SkyTerra (i) will make such changes and additions
thereto as reasonably requested by counsel to Motient prior to filing any
registration statement or amendment thereto or any prospectus or any supplement
thereto and (ii) if Motient is an underwriter or controlling person of SkyTerra,
to include therein material relating to Motient or the plan of distribution for
the Common Shares registered thereunder, furnished to SkyTerra in writing,
which, in the reasonable judgment of Motient, should be included;

 

  (b) furnish to Motient such number of copies of such registration statement,
each amendment and supplement thereto, the prospectus included in such
registration statement and such other documents as Motient may reasonably
request in order to facilitate the disposition of such Common Shares registered
thereunder; provided, however, that SkyTerra shall have no obligation to furnish
copies of a final prospectus if the conditions of Rule 172(c) under the
Securities Act are satisfied by SkyTerra;

 

  (c) prepare and file with the SEC such amendments and supplements to such
registration statement and the prospectus used in connection therewith as may be
necessary to keep such registration statement with respect to such Common Shares
registered thereunder effective for the applicable time periods as specified in
Section 1.1 in order to complete the disposition of the Common Shares covered by
such registration statement and comply with the provisions of the Securities Act
with respect to the disposition of all Common Shares covered by such
registration statement during such period in accordance with the intended
methods of disposition thereof as set forth in such registration statement;

 

  (d) use its commercially reasonable efforts to register or qualify such Common
Shares under such other securities or blue sky laws of such jurisdictions as
Motient (or any other holder whose securities are included in a registration
statement on which Common Shares are registered) reasonably requests and do any
and all other acts and things which may be reasonably necessary or advisable to
enable Motient to consummate the disposition in such jurisdictions of the Common
Shares owned by

 

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Motient (provided that SkyTerra shall not be required to (i) qualify generally
to do business in any jurisdiction where it would not otherwise be required to
qualify but for this subsection, (ii) subject itself to taxation in any such
jurisdiction or (iii) consent to general service of process in any such
jurisdiction);

 

  (e) notify Motient, at any time when a prospectus relating thereto is required
to be delivered under the Securities Act, (i) when a registration statement or
any post-effective amendment has become effective under the Securities Act,
(ii) of any written request by the SEC for amendments or supplements to such
registration statement or prospectus, (iii) of the happening of any event as a
result of which the prospectus included in such registration statement contains
an untrue statement of a material fact or omits any fact necessary to make the
statements therein, in light of the circumstances under which they were made,
not misleading (whereupon Motient shall immediately cease any offers, sales or
other distribution of Common Shares registered thereunder), and, subject to
1.3(c), SkyTerra shall promptly prepare a supplement or amendment to such
prospectus so that, as thereafter used by Motient for the resale of the Common
Shares or delivered to the stockholders of Motient in connection with the
distribution of such Common Shares, such prospectus shall not contain an untrue
statement of a material fact or omit to state any fact necessary to make the
statements therein, in light of the circumstances under which they were made,
not misleading, and (iv) of the issuance of any stop order suspending the
effectiveness of a registration statement, or of any order suspending or
preventing the use of any related prospectus or suspending the qualification of
any of the Common Shares included in such registration statement for sale or
distribution in any jurisdiction;

 

  (f) in the event of the issuance of any stop order suspending the
effectiveness of a registration statement, or of any order suspending or
preventing the use of any related prospectus or suspending the qualification of
any Common Shares included in such registration statement for sale or
distribution in any jurisdiction, SkyTerra shall use its commercially reasonable
efforts promptly to obtain the withdrawal of such order and shall prepare and
file an amended or supplemented prospectus, if required; and

 

  (g) provide a transfer agent and registrar for all such Common Shares not
later than the effective date of such registration statement;

 

  (h) use its commercially reasonable efforts to cause such Common Shares
covered by such registration statement to be registered with or approved by such
other governmental agencies or authorities as may be necessary to enable Motient
to complete the disposition of the Common Shares covered by such registration
statement and comply with the provisions of the Securities Act with respect to
the disposition of all Common Shares covered by such registration statement
during such period in accordance with the intended methods of disposition by
Motient thereof set forth in such registration statement;

 

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  (i) make available for inspection by Motient, any underwriter participating in
any disposition pursuant to such registration statement, and any attorney,
accountant or other agent retained by Motient or underwriter, all financial and
other records, pertinent corporate documents and properties of SkyTerra, and
cause SkyTerra’s officers, managers, employees and independent accountants to
supply all information reasonably requested by SkyTerra, underwriter, attorney,
accountant or agent in connection with such registration statement; and

 

  (j) make generally available to its stockholders a consolidated earnings
statement (which need not be audited) for the 12 months beginning after the
effective date of such registration statement as soon as reasonably practicable
after the end of such period, which earnings statement shall satisfy the
requirements of an earning statement under Section 11(a) of the Securities Act.

1.3 Other Procedural Matters.

 

  (a) SEC Correspondence. SkyTerra shall make available to Motient promptly
after the same is prepared and publicly distributed, filed with the SEC, or
received by SkyTerra, one copy of each registration statement and any amendment
thereto, each preliminary prospectus and each amendment or supplement thereto,
each letter written by or on behalf of SkyTerra to the SEC or the staff of the
SEC (or other governmental agency or self-regulatory body or other body having
jurisdiction, including any domestic or foreign securities exchange), in each
case relating to such registration statement. SkyTerra will promptly respond to
any and all comments received from the SEC, with a view towards causing each
registration statement or any amendment thereto to be declared effective by the
SEC as soon as practicable and shall file an acceleration request as soon as
practicable following the resolution or clearance of all SEC comments or, if
applicable, following notification by the SEC that any such registration
statement or any amendment thereto will not be subject to review.

 

  (b) SkyTerra may require Motient to furnish to SkyTerra any other information
regarding Motient and the distribution of such securities, including without
limitation the plan of disposition of the Common Shares, as SkyTerra reasonably
determines, is required to be included in any registration statement.

 

  (c) Motient agrees that, upon notice from SkyTerra of the happening of any
event as a result of which the prospectus included in such registration
statement contains an untrue statement of a material fact or omits any material
fact necessary to make the statements therein not misleading (a “Suspension
Notice”), Motient will forthwith discontinue disposition of Common Shares
pursuant to such registration statement until Motient is advised in writing by
SkyTerra that the use of the prospectus may be resumed and is furnished with a
supplemented or amended prospectus as contemplated by Section 1.2 hereof;
provided, however, that such postponement of sales of Common Shares by Motient
shall not in any event exceed (i) twenty (20) consecutive days or
(ii) forty-five (45) days in the aggregate in any 12 month period. If SkyTerra
shall give Motient any Suspension Notice, SkyTerra shall extend the

 

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period of time during which SkyTerra is required to maintain the applicable
registration statements effective pursuant to this Agreement by the number of
days during the period from and including the date of the giving of such
Suspension Notice to and including the date Motient either is advised by
SkyTerra that the use of the prospectus may be resumed. In any event, SkyTerra
shall not be entitled to deliver more than a total of three (3) Suspension
Notices or notices of any Delay Period in any 12 month period.

 

  (d) Neither SkyTerra nor Motient shall permit any officer, manager,
underwriter, broker or any other person acting on behalf of SkyTerra to use any
free writing prospectus (as defined in Rule 405 under the Securities Act) in
connection with any registration statement covering Common Shares filed pursuant
to the Exchange Agreement or this Agreement, without the prior written consent
of SkyTerra, Motient and any underwriter.

1.4 Expenses.

 

  (a) Registration Expenses. All Registration Expenses shall be borne by
SkyTerra.

 

  (b) Selling Expenses. All expenses incident to Motient’s performance of or
compliance with this Agreement, including, without limitation, all fees and
expenses of counsel for Motient, fees and expenses of Motient’s transfer agent,
and any broker or dealer discounts or commissions attributable to the
disposition of Common Shares shall be borne solely by Motient.

SECTION 2. LOCKUP AGREEMENT.

2.1 Except for the (i) disposition of Common Shares by Motient to its
stockholders pursuant to the Preferred Registration Statement and (ii) the
distribution by Motient of Common Shares to holders of Motient common stock as
described in Section 4.8 of the MSV Exchange Agreement, Motient hereby agrees to
not effect any public sale or distribution (including any sales pursuant to Rule
144) of equity securities of SkyTerra, or any securities convertible into or
exchangeable or exercisable for such securities, during the seven days prior to
and the 90-day period beginning on the effective date of any underwritten
registered public offering of equity securities of SkyTerra or securities
convertible or exchangeable into or exercisable for equity securities of
SkyTerra (except as part of such underwritten registration), unless the
underwriters managing the registered public offering otherwise consent in
writing, and Motient will deliver an undertaking to the managing underwriters
(if requested) consistent with this covenant. Motient shall not be obligated to
comply with the provisions of this Section 2.1 more than two times in any
12-month period.

SECTION 3. INDEMNIFICATION.

3.1 Indemnification by SkyTerra. SkyTerra agrees to indemnify, to the extent
permitted by law, Motient, its officers, directors, employees and Affiliates and
each Person who controls Motient (within the meaning of the Securities Act)
against all losses, claims, damages, liabilities, and expenses caused by any
untrue or alleged untrue statement of material fact contained in any
registration statement described in this Agreement and/or the MSV Exchange
Agreement,

 

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(including, without limitation, the Distribution Registration Statement (as
defined in the MSV Exchange Agreement), the Resale Registration Statement and
the Preferred Registration Statement) (each a “Transaction Registration
Statement”) or any prospectus forming a part of any such Transaction
Registration Statement or any “issuer free writing prospectus” (as defined in
Securities Act Rule 433), or any amendment thereof or supplement thereto or any
omission or alleged omission of a material fact required to be stated therein or
necessary to make the statements therein, in light of the circumstances under
which they were made, not misleading or any violation or alleged violation by
SkyTerra of the Securities Act, the Exchange Act or applicable “blue sky” laws,
except insofar as the same are made in reliance and in conformity with any
information furnished in writing to SkyTerra by Motient expressly for use
therein or by the failure of Motient to deliver a copy of such registration
statement or prospectus or any amendments or supplements thereto as required by
law after SkyTerra has furnished Motient with a sufficient number of copies of
the same.

3.2 Indemnification by Motient. In connection with any registration statement in
which Motient is participating, Motient shall furnish to SkyTerra in writing
such information as SkyTerra reasonably requests for use in connection with any
such registration statement or prospectus and, to the extent permitted by law,
shall indemnify SkyTerra, its directors, officers, employees and Affiliates, and
each Person who controls SkyTerra (within the meaning of the Securities Act),
against any losses, claims, damages, liabilities, and expenses resulting from
any untrue or alleged untrue statement of material fact contained in any
Transaction Registration Statement, the prospectus or preliminary prospectus
forming a part of such Transaction Registration Statement or any amendment
thereof or supplement thereto or any omission or alleged omission of a material
fact required to be stated therein or necessary to make the statements therein,
in light of the circumstances under which they were made, not misleading, but
only to the extent that any information so furnished in writing by Motient
contains such untrue statement or omits a material fact required to be stated
therein necessary to make the statements therein not misleading; provided,
however, that any such obligation of Motient to indemnify SkyTerra hereunder
shall be limited to (i) the net proceeds to Motient from the sale of the Common
Shares pursuant to the Resale Registration Statement in the case of the Resale
Registration Statement, and (ii) the value of the Common Shares distributed
pursuant to the Distribution Registration Statement or the Preferred
Registration Statement, as applicable, based on the average of the high and low
sales price of Common Shares for the five trading day period immediately prior
to the date of such distribution with respect to the Distribution Registration
Statement or the Preferred Registration Statement, as applicable.

3.3 Indemnification Procedures. Any Person entitled to indemnification hereunder
shall (i) give prompt written notice to the indemnifying party of any claim with
respect to which it seeks indemnification (provided that the failure to give
prompt notice shall not impair any Person’s right to indemnification hereunder
to the extent such failure has not prejudiced the indemnifying party) and
(ii) unless in such indemnified party’s reasonable judgment a conflict of
interest between such indemnified and indemnifying parties may exist with
respect to such claim, permit such indemnifying party to assume the defense of
such claim with counsel reasonably satisfactory to the indemnified party. If
such defense is assumed, the indemnifying party shall not be subject to any
liability for any settlement made by the indemnified party without its consent
(but such consent shall not be unreasonably withheld). An indemnifying party who
is not entitled to, or elects not to, assume the defense of a claim shall not be
obligated to pay the fees and expenses of more than one

 

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counsel (in addition to local counsel) for all parties indemnified by such
indemnifying party with respect to such claim, unless in the reasonable judgment
of any indemnified party there may be one or more legal or equitable defenses
available to such indemnified party that are in addition to or may conflict with
those available to another indemnified party with respect to such claim. Failure
to give prompt written notice shall not release the indemnifying party from its
obligations hereunder.

3.4 Investigation; Contribution. The indemnification provided for under this
Agreement shall remain in full force and effect regardless of any investigation
made by or on behalf of the indemnified party or any officer, director, or
controlling Person of such indemnified party and shall survive the transfer of
securities. If the indemnification provided under Section 3.1 or Section 3.2 of
this Agreement is held by a court to be unavailable or unenforceable in respect
of any losses, claims, damages, liabilities or expenses referred to herein, then
each applicable indemnifying party, in lieu of indemnifying such indemnified
party, shall contribute to the amount paid or payable by such indemnified Person
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 on the one hand and of the indemnified party on the other in connection
with the statements or omissions that result in such losses, claims, damages,
liabilities or expenses as well as any other relevant equitable considerations.
The relative fault of the indemnifying party on the one hand and of the
indemnified Person on the other shall be determined by reference to, among other
things, whether the untrue or alleged untrue statement of a material fact or the
omission or alleged omission to state a material fact relates to information
supplied by the indemnifying party or by the indemnified party, and by such
party’s relative intent, knowledge, access to information and opportunity to
correct or prevent such statement or omission. In no event shall the liability
of Motient for contribution pursuant to this Section 3.4 be greater than the
amount for which Motient would have been liable pursuant to Section 3.2 had
indemnification been available and enforceable.

SECTION 4. RULE 144 TRANSACTIONS.

4.1 Undertaking to File Reports and Cooperate in Rule 144 Transactions. For as
long as Motient continues to hold or has the right under the MSV Exchange
Agreement to acquire any Acquired Shares, SkyTerra shall use its commercially
reasonable efforts to file with the SEC, on a timely basis, all annual,
quarterly and other periodic reports required to be filed by it under Sections
13 and 15(d) of the Exchange Act, and the rules and regulations thereunder;
provided, however, that the foregoing shall not be construed to require SkyTerra
to prepare and file periodic reports if it is not required to do so under the
Exchange Act. In the event of any proposed sale by Motient of Acquired Shares
pursuant to Rule 144 under the Securities Act or otherwise as provided herein,
which sale is to be made in accordance with the terms of Section 5.1(d) hereof,
SkyTerra shall use its commercially reasonable efforts to cooperate with Motient
so as to enable such sales to be made in accordance with applicable laws, rules
and regulations, the requirements of the transfer agent of SkyTerra, and the
reasonable requirements of the broker through which the sales are proposed to be
executed, and shall, upon written request, furnish unlegended certificates
representing ownership of the shares of Common Shares sold thereby, such
certificates to be furnished in such numbers and denominations as Motient may
reasonably request.

 

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SECTION 5. RESTRICTIONS ON TRANSFER.

5.1 Permitted Transfers. Motient hereby agrees that, until it and any permitted
transferees under paragraph (e) or (h) hereunder have disposed of all of the
Acquired Shares, it will not, directly or indirectly, without the prior written
consent of SkyTerra, sell, distribute, transfer or otherwise dispose (in each
case, a “Disposition”) of any Acquired Shares except:

 

  (a) the pro rata distribution of Common Shares by Motient to its common
stockholders in the form of a special dividend as described by Section 4.8 of
the MSV Exchange Agreement; or

 

  (b) distributions of Common Shares by Motient to its preferred stockholders
pursuant to the Preferred Registration Statement;

 

  (c) sales of Resale Shares pursuant to the Resale Registration Statement; or

 

  (d) sales of Resale Shares pursuant to Rule 144 under the Securities Act; or

 

  (e) sales or transfers of Resale Shares to any Person or group of related
Persons who would immediately thereafter not own or have the right to acquire or
vote with respect to Resale Shares consisting of, in the aggregate, more than
five percent (5%) (with each Person, other than Affiliates of the transferring
Holder, considered individually and not in the aggregate with other transferees)
of the total combined voting power of all SkyTerra Common Shares then
outstanding; provided, however, that in each such case, the transferee shall
receive and hold such Resale Shares subject to, and the transferee and all of
the transferees’ Affiliates shall agree to be bound by, all the terms of this
Agreement, which terms shall also inure to the benefit of such transferees, and
there shall be no further transfer of such Resale Shares, except in accordance
with the provisions of this Section 5.1; or

 

  (f) a bona fide pledge of or the granting of a security interest in the Resale
Shares or Resale Shares to an institutional lender for money borrowed, provided
that such lender acknowledges in writing that it has received a copy of this
Agreement and agrees, upon its becoming the owner of, or obtaining dispositive
authority with respect to or in connection with any disposition of, any such
Resale Shares, to be bound by the provisions of this Agreement in connection
with any right it may have to dispose of any such Resale Shares (and, upon
agreeing so to be bound, the provisions of this Agreement shall inure to the
benefit of such party); or

 

  (g) sales or transfers of Resale Shares pursuant to a tender or exchange offer
which the Board of Directors of SkyTerra does not oppose within 10 business days
after the date of commencement (as such term is defined in Rule 14d-2(a) of the
General Rules and Regulations under the Exchange Act) of such offer; or

 

  (h) dispositions of Resale Shares by Motient to any wholly owned subsidiary of
Motient or to a successor corporation of Motient; provided, however, that in
each such case, the transferee shall receive and hold such Resale Shares subject
to, and the transferee and all of the transferees’ Affiliates shall agree to be
bound by, all the

 

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terms of this Agreement, which terms shall also inure to the benefit of such
transferees, and there shall be no further transfer of such Resale Shares for
which they are exchangeable, except in accordance with the provisions of this
Section 5.1; or

 

  (i) dispositions pursuant to any merger, consolidation, reorganization or
recapitalization to which SkyTerra is a party or in connection with any
reclassification of the Acquired Shares or the Common Shares;

provided, that in the event that Motient seeks to effect a Disposition of any
Resale Shares pursuant to clauses (d), (e) or (h) of this Section 5.1, (i) such
Disposition is made in compliance with applicable securities laws, and
(ii) prior to such Disposition, Motient shall have delivered to SkyTerra an
opinion of counsel stating that such Disposition (A) is permitted by this
Agreement and the MSV Exchange Agreement, (B) does not require registration
under the Securities Act, and (C) assuming the accuracy of the representations
and warranties set forth in the MSV Exchange Agreement, does not cause the MSV
Exchange to be required to have been registered under the Securities Act;
provided, that with respect to Dispositions pursuant to Section 5.1(d), such
opinion shall only be required if requested by SkyTerra’s transfer agent and in
any event no opinion shall be required for Dispositions pursuant to Rule 144(k)
under the Securities Act.

SECTION 6. INTENTIONALLY OMITTED

SECTION 7. DEFINITIONS.

“Affiliate” means, with respect to any specified Person, any other Person that,
directly or indirectly or through one or more intermediaries, controls, is
controlled by or is under common control with such specified Person.

“Exchange Act” means the Securities Exchange Act of 1934, as amended, and the
rules and regulations thereunder, or any successor statute.

“Person” means any individual, firm, partnership, corporation, trust, joint
venture, limited liability company, association, joint stock company,
unincorporated organization, or any other entity or organization, including a
governmental entity or any department, agency, or political subdivision thereof.

“Registration Expenses” means all expenses incident to SkyTerra’s performance of
or compliance with this Agreement, including without limitation all registration
and filing fees, fees and expenses of compliance with securities or blue sky
laws, fees with respect to filings required to be made with the NASD, printing
expenses, messenger and delivery and mailing expenses, fees and disbursements of
custodians, and fees and disbursements of counsel for SkyTerra and all
independent certified public accountants retained by SkyTerra and other Persons
retained by SkyTerra.

“Securities Act” means the Securities Act of 1933, as amended, and the rules and
regulations thereunder, or any successor statute.

 

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SECTION 8. MISCELLANEOUS.

8.1 Legends and Stop Transfer Orders.

 

  (a) Motient hereby agrees that all certificates representing Acquired Shares
or the Common Shares for which they are exchanged that are presently owned or
are hereafter acquired by Motient, shall have the following legend (or other
legend to the same effect): “The shares represented by this certificate are
subject to restrictions on transfer and other restrictions pursuant to the
provisions of a Registration Rights Agreement, dated May 6, 2006, between
SkyTerra Communications, Inc. and Motient Corporation, a copy of which is on
file at the office of the corporate secretary of Motient Corporation.”

 

  (b) Motient hereby agrees to the entry of stop transfer orders with the
transfer agent and registrar of the Acquired Shares or the Common Shares for
which they are exchanged against the transfer (other than in compliance with
this Agreement) of legended securities held by Motient (or its permitted
transferees under Section 5.1(e) or (h) hereof).

 

  (c) SkyTerra agrees to remove any stop transfer orders provided in paragraph
(b) above in sufficient time to permit any party to make any transfer permitted
by the terms of this Agreement.

8.2 Consolidation or Merger of SkyTerra.

For as long as Motient continues to hold, or has the right under the MSV
Exchange Agreement to acquire, any Acquired Shares, if any of the following
events (collectively, a “SkyTerra Change of Control”) occurs, namely:

(a) any reclassification or exchange of the outstanding Common Shares (other
than a change in par value, or from par value to no par value, or from no par
value to par value, or as a result of a subdivision or combination);

(b) any merger, consolidation, statutory share exchange or combination of
SkyTerra with another corporation as a result of which holders of Common Shares
shall be entitled to receive stock or other securities with respect to or in
exchange for such Common Shares; or

(c) any sale or conveyance of the properties and assets of SkyTerra as, or
substantially as, an entirety to any other corporation as a result of which
holders of Common Shares shall be entitled to receive stock or other securities
with respect to or in exchange for such Common Shares;

SkyTerra shall enter into, or SkyTerra shall cause the successor or purchasing
corporation to enter into, as the case may be, an agreement with Motient that
provides Motient with substantially similar rights as provided in this Agreement
with respect to the stock or other securities to be issued in the SkyTerra
Change of Control transaction with respect to or in exchange for the Acquired
Shares and/or Common Shares.

 

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EXECUTION

8.3 Specific Performance. The parties hereto acknowledge and agree that in the
event of any breach of this Agreement, the non-breaching parties would be
irreparably harmed and could not be made whole by monetary damages. It is
accordingly agreed that the parties hereto shall and do hereby waive the defense
in any action for specific performance that a remedy at law would be adequate
and that the parties hereto, in addition to any other remedy to which they may
be entitled at law or in equity, shall be entitled to compel specific
performance of this Agreement in any action instituted hereunder.

8.4 Amendments and Waivers. The failure of any party to enforce any of the
provisions of this Agreement shall in no way be construed as a waiver of such
provisions and shall not affect the right of such party thereafter to enforce
each and every provision of this Agreement in accordance with its terms. No
modification, amendment, or waiver of any provision of this Agreement shall be
effective against Motient or SkyTerra except by a written agreement signed by
Motient and SkyTerra.

8.5 Successors and Assigns. All covenants and agreements in this Agreement by or
on behalf of any of the parties hereto shall bind and inure to the benefit of
the respective successors and permitted assigns of the parties hereto whether so
expressed or not including, without limitation, any Person which is the
successor to Motient or SkyTerra.

8.6 Severability. If any term, provision, covenant or restriction of this
Agreement, or any part thereof, is held by a court of competent jurisdiction or
any foreign federal, state, county, or local government or any other
governmental, regulatory, or administrative agency or authority to be invalid,
void, unenforceable, or against public policy for any reason, the remainder of
the terms, provisions, covenants, and restrictions of this Agreement shall
remain in full force and effect and shall in no way be affected, impaired, or
invalidated.

8.7 Entire Agreement. Except as otherwise expressly set forth herein, this
document embodies the complete agreement and understanding among the parties
hereto with respect to the subject matter hereof and supersedes and preempts any
prior understandings, agreements, or representations by or among the parties,
written or oral, which may have related to the subject matter hereof in any way.

8.8 Counterparts. This Agreement may be executed in two or more counterparts,
each of which shall be deemed an original, but all of which shall constitute one
and the same instrument, and it shall not be necessary in making proof of this
Agreement to produce or account for more than one such counterpart.

8.9 Headings. The headings in this Agreement are for convenience of reference
only and shall not limit or otherwise affect the meaning of terms contained
herein.

8.10 GOVERNING LAW; CONSENT OF EXCLUSIVE JURISDICTION; WAIVER OF JURY TRIAL.
THIS AGREEMENT AND THE VALIDITY AND PERFORMANCE OF THE TERMS HEREOF SHALL BE
GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK
WITHOUT REGARD TO PRINCIPLES OF CONFLICTS OF LAW OR CHOICE OF LAW. THE PARTIES
HERETO HEREBY AGREE THAT ALL ACTIONS OR PROCEEDINGS ARISING DIRECTLY OR

 

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EXECUTION

INDIRECTLY FROM OR IN CONNECTION WITH THIS AGREEMENT SHALL BE LITIGATED ONLY IN
THE STATE OR FEDERAL COURTS LOCATED IN MANHATTAN IN THE STATE OF NEW YORK. TO
THE EXTENT PERMITTED BY APPLICABLE LAW, THE PARTIES HERETO CONSENT TO THE
EXCLUSIVE JURISDICTION AND VENUE OF THE FOREGOING COURTS AND CONSENT THAT ANY
PROCESS OR NOTICE OF MOTION OR OTHER APPLICATION TO EITHER OF SAID COURTS OR A
JUDGE THEREOF MAY BE SERVED INSIDE OR OUTSIDE THE STATE OF NEW YORK BY
REGISTERED MAIL, RETURN RECEIPT REQUESTED, DIRECTED TO SUCH PARTY AT ITS ADDRESS
SET FORTH IN THIS AGREEMENT (AND SERVICE SO MADE SHALL BE DEEMED COMPLETE FIVE
(5) DAYS AFTER THE SAME HAS BEEN POSTED AS AFORESAID) OR BY PERSONAL SERVICE OR
IN SUCH OTHER MANNER AS MAY BE PERMISSIBLE UNDER THE RULES OF SAID COURTS. THE
PARTIES HERETO HEREBY WAIVE ANY RIGHT TO A JURY TRIAL IN CONNECTION WITH ANY
LITIGATION PURSUANT TO THIS AGREEMENT.

8.11 Notices. Any notices, reports or other correspondence (hereinafter
collectively referred to as “correspondence”) required or permitted to be given
hereunder shall be given in writing and shall be deemed given three business
days after the date sent by certified or registered mail (return receipt
requested), one business day after the date sent by overnight courier or on the
date given by telecopy (with confirmation of receipt) or delivered by hand, to
the party to whom such correspondence is required or permitted to be given
hereunder.

To Motient:

Motient Corporation

300 Knightsbridge Parkway

Lincolnshire Parkway

Lincolnshire, IL 60069

Facsimile: (847) 478-4810

Attention: General Counsel

with a copy (which shall not constitute notice) to:

Andrews Kurth LLP

600 Travis Street, Suite 4200

Houston, Texas 77002

Telecopy: (713) 238-7111

Attention: Mark Young

To SkyTerra:

SkyTerra Communications, Inc.

19 West 44th Street, Suite 507

New York, New York 10036

Facsimile:

Attn: Robert C. Lewis

 

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EXECUTION

with a copy (which shall not constitute notice) to:

Skadden, Arps, Slate, Meagher & Flom LLP

Four Times Square

New York, New York 10036

Facsimile: (917) 777-2918

Attn: Gregory A. Fernicola, Esq.

 

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EXECUTION

IN WITNESS WHEREOF, the parties hereto have executed this Registration Rights
Agreement on the day and year first above written.

 

SKYTERRA COMMUNICATIONS, INC. By:  

/s/ Jeffrey A. Leddy

Name:   Jeffrey A. Leddy Title:   Chief Executive Officer and President MOTIENT
CORPORATION By:  

/s/ Christopher Downie

Name:   Christopher Downie Title:  

Executive Vice President

and Chief Operating Officer

 

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