<PAGE>   1
                              AMENDED AND RESTATED
                              EMPLOYMENT AGREEMENT

         THIS AMENDED AND RESTATED EMPLOYMENT AGREEMENT (the "Amended
Agreement") is made as of this 1st day of September 1999 (the "Effective Date")
between ORBCOMM GLOBAL, L.P. (the "Company") and ROBERT F. LATHAM (the
"Executive").

                              W I T N E S S E T H:

         WHEREAS, the Company and the Executive previously entered into that
certain Employment Agreement (the "Employment Agreement") dated as of May 15,
1997 (the "Original Effective Date"); and

         WHEREAS, the Company and the Executive desire to amend and restate the
Employment Agreement as set forth herein.

         NOW, THEREFORE, the Company and the Executive each agree as follows:

         1.       Employment; Duties. During the term of this Amended
Agreement, the Company hereby employs the Executive and the Executive accepts
employment as Executive Vice President, Special Projects of the Company. In
such capacity, the Executive shall perform such duties as may be assigned to
him from time to time by the Chairman and Chief Executive Officer of the
Company. During his period of employment with the Company, the Executive will
(a) work out of his home office, unless requested otherwise, and (b) devote his
best efforts to those duties assigned to him hereunder and shall not engage in
any employment or activities detrimental to the best interests of the Company
without the approval of the Chairman and Chief Executive Officer of the
Company. Except as otherwise provided herein, the Executive shall not conduct
any activities on behalf of the Company or hold himself out as representing the
Company except at the direction of the Chairman and Chief Executive Officer or
his designee. The Company understands and agrees that, notwithstanding the
foregoing, and subject to Sections 6(a) and (b), the Executive may serve during
the term of this Amended Agreement as a director on the boards of directors of
business, civic or community corporations or entities other than the Company,
if he shall obtain the prior written approval of the Company's General
Partners, which approval may be withheld if the Company's General Partners
reasonably determine that the Executive's so serving as a director for any such
corporation or entity would interfere with the performance of the Executive's
duties hereunder or would conflict with the best interests of the Company.

         2.       Term. The term of this Amended Agreement shall commence on
the Effective Date and end on September 30, 1999. This Amended Agreement shall
not be renewable by either party.

         3.       Compensation. During the term of this Amended Agreement, the
Company shall pay to the Executive compensation equal to an annual base salary
at the rate of two hundred

<PAGE>   2


thirty-three thousand dollars ($233,000) per annum, prorated for any partial
employment year, payable in bi-weekly installments in arrears.

         4.       Other Compensation and Benefits.

         (a)      Payment on Expiration. On the expiration of the term of this
Amended Agreement, the Company shall pay the Executive a lump sum payment equal
to two hundred sixty-three thousand, eight hundred forty-nine dollars
($263,849). The payment of this amount and performance by the Company of its
other obligations set forth in this Agreement shall constitute full and final
satisfaction of all of the Company's obligations to the Executive, and all of
the Executive's rights, under this Amended Agreement and the Employment
Agreement.

         (b)      Legal Review of Amended Agreement. The Company shall pay the
Executive's actual legal expenses incurred in the review of this Amended
Agreement, up to a maximum of $1,000.

         (c)      Benefits. During the term of this Amended Agreement, the
Executive shall be entitled to participate in any profit sharing plan,
retirement plan, group life insurance plan or other insurance plan or medical
expense plan maintained by the Company for its senior executives generally and,
if applicable, their family members. The Company reserves the right to
discontinue or to amend such plans to conform to legal requirements or for
other reasons, as determined by the Company to be in the best interest of the
business.

         (d)      Directors and Officers Insurance. The Company shall use all
commercially reasonable efforts to maintain Directors and Officers Insurance
covering such claims and in such amounts as the Company shall determine to be
appropriate.

         (e)      Options. On the Original Effective Date, the Executive was
granted options (the "Options") to purchase 55,000 shares of the Common Stock,
par value $.01 per share (the "Common Stock"), of Orbital Communications
Corporation ("OCC"). Each Option was exercisable in accordance with the terms
set forth in the stock option agreement reflecting such grant; provided that
notwithstanding the vesting schedule set forth in such agreement, the parties
agree that as of the expiration of the term of this Amended Agreement, the
vesting schedule for the Options shall be revised for unvested options such
that, vesting of the next annual installment (e.g. 13,750) shall be deemed to
have occurred in equal quarters amounts (e.g. approximately, 3,438) for each
full calendar quarter the Executive was employed by the Company (from the last
annual vesting date) prior to the such expiration date. In addition, on the
exercise of any vested portion of the Options, payment of any withholding taxes
then due could be made by the Executive (i) surrendering Common Stock held by
the Executive having a fair market value equal to such withholding tax
obligation or (ii) requesting that OCC withhold from the shares to be delivered
to the Executive on the exercise of vested Options a number of shares of Common
Stock having a fair market value equal to such withholding tax obligation.

         5.       Business Expenses; Professional Memberships. During the term
of this Amended Agreement, the Company shall reimburse the Executive for all
reasonable and necessary (a)

                                      -2-

<PAGE>   3


business expenses, including, but not limited to, travel expenses and telephone
usage charges incurred by him in the performance of his duties under this
Amended Agreement, and (b) professional membership dues, against presentation
of proper receipts or other proof of expenditure, and subject to such
reasonable guidelines or limitations provided to the Executive, and which are
to be applied prospectively only as the General Partners or the Chief Executive
Officer of the Company may impose. The Executive shall be furnished with a
portable computer (including monitor) and a docking station for use in his
home, as well as a printer for use in his home. On the expiration of the term
of this Amended Agreement, the Executive shall be entitled to retain, and the
Company shall be deemed to have transferred to the Executive title to, such
portable computer (including monitor), docking station and printer.

         6.       Company Matters.

         (a)      Proprietary Information and Inventions.  On the Original
Effective Date, the Executive executed an Employee Non-Disclosure Agreement.
The Executive agrees to abide by the terms and conditions set forth therein.

         (b)      Non-Solicitation of Employees; Non-Compete. The Executive
agrees that, during the term of this Amended Agreement and for a period of one
year thereafter, he will not solicit or encourage any employee of the Company
to terminate his or her employment with the Company or to accept employment
with any other employer with whom the Executive might become affiliated
subsequent to his termination. In addition, the Executive reaffirms his
obligations under the each of the stock option agreements reflecting the grant
of stock options to the Executive on May 15, 1997, July 18, 1997 and January
16, 1998 (the "Stock Option Agreements"), including those obligations set forth
in Section 7 thereof, and agrees to abide by the covenants and agreements set
forth therein. The parties also agree that the term of the non-competition set
forth in Section 7 of the Stock Option Agreements shall continue for a period
of twelve months after the expiration of the term of this Amended Agreement.

         (c)      Resignation on Termination. On expiration of the term of this
Amended Agreement, the Executive shall immediately resign any directorships,
offices or other positions that he may hold in the Company or any of its
affiliates.

         7.       Miscellaneous.

         (a)      Work Authorization. The Company shall be responsible for
obtaining all appropriate work authorization papers necessary for the Executive
to be employed by the Company during the term of this Amended Agreement.

         (b)      Entire Agreement; Binding Effect. This Amended Agreement sets
forth the entire understanding between the parties as to the subject matter of
this Amended Agreement and merges and supersedes all prior agreements,
commitments, representations, writings and discussions between them including
the terms of the Employment Agreement; and neither of the parties shall be
bound by any obligations, conditions, warranties or representations with
respect to the subject matter of this Amended Agreement, other than as
expressly provided in this


                                      -3-

<PAGE>   4

Amended Agreement or as duly set forth on or subsequent to the date of
execution of this Amended Agreement in writing and signed by the proper and
duly authorized representative of the party to be bound hereby. This Amended
Agreement is binding on the Executive and on the Company and its successors and
assigns (whether by assignment, by operation of law or otherwise).

         (c)      Notices. All notices, approvals, consents, requests or
demands required or permitted to be given under this Amended Agreement shall be
in writing and shall be deemed sufficiently given three business days after
being deposited in the mail, registered or certified, postage prepaid, on
receipt if hand delivered or sent by facsimile (answerback received) or one
business day after being given to a reputable overnight courier and addressed
to the party entitled to receive such notice at the following address (or other
such addresses as the parties may subsequently designate):

                 The Company:              ORBCOMM Global, L.P.
                                           2455 Horse Pen Road
                                           Dulles, Virginia  20171

                 The Executive:

                                           21586 Misty Creek Lane
                                           Fairfax, Virginia  22033

         If notice is given by any other method, it shall be deemed effective
when the written notice is actually received.

         (d)      Waivers. No party shall be deemed to have waived any right,
power or privilege under this Amended Agreement or any provisions hereof unless
such waiver shall have been duly executed in writing and acknowledged by the
party to be charged with such waiver. The failure of any party at any time to
insist on performance of any of the provisions of this Amended Agreement shall
in no way be construed to be a waiver of such provisions, nor in any way to
affect the validity of this Amended Agreement or any part hereof. No waiver of
any breach of this Amended Agreement shall be held to be a waiver of any other
subsequent breach.

         (e)      Governing Law; Jurisdiction. This Amended Agreement shall be
governed by, and construed and enforced in accordance with, the laws of the
Commonwealth of Virginia, without giving effect to the conflict or choice of
law provisions thereof. In addition, each party hereto irrevocably and
unconditionally agrees that any suit, action or other legal proceeding arising
out of this Amended Agreement may be brought only in the Commonwealth of
Virginia.

         (f)      Release. In consideration of the agreements, covenants and
understandings contained herein, the Executive hereby releases, acquits and
forever discharges the Company, its subsidiaries, affiliates and successors and
any of their officers, partners, directors and employees, including but not
limited to Orbital Sciences Corporation and Teleglobe Inc. (collectively, the
"ORBCOMM Entities") of and from, and hereby waives all his rights with respect
to, any and all

                                      -4-

<PAGE>   5

rights, actions, suits, claims, causes of actions, damages, expenses or costs
of whatever nature arising out of, related to, or in connection with (a) the
Company's employment of the Executive and any and all other contracts and
agreements, whether oral or in writing, relating to such employment, (b) the
ORBCOMM Retirement Savings Plan for Employees of ORBCOMM Global, L.P., ORBCOMM
USA, L.P. and ORBCOMM International Partners, L.P. (the "ORBCOMM 401(k)"), (c)
any health or other benefit plans maintained by the Company or its affiliates,
(d) the matters set forth herein and (e) the Company's interactions with the
Executive, in the case of each of (a) - (e) above, up to the date of execution
of this Amended Agreement, including, but not limited to, any rights, actions,
suits, claims, causes of action, or liability under (i) any federal, state, or
local statute or regulation including, but not limited to, the Age
Discrimination in Employment Act ("ADEA"), or (ii) under common law principles,
except claims or proceedings necessary to enforce the provisions of this
Amended Agreement. The Executive further covenants and agrees never to join in
or commence any action, suit or proceeding, in law or in equity, or before any
administrative agency other than the Equal Employment Opportunity Commission,
or to incite, encourage, or participate in any such action, suit or proceeding,
against the ORBCOMM Entities in any way pertaining to or arising out of any
matters pertaining to this Amended Agreement. This Amended Agreement is
intended to include in its effect even claims not known or suspected to exist
at the time its execution. Claims that may arise (A) under the ADEA or (B)
relative to the ORBCOMM 401(k), or any health or other benefit plans maintained
by the Company or its affiliates, in either case after the date of the
execution of this Amended Agreement, are not released.

         (g)      Acknowledgement of Voluntariness. The Executive acknowledges
that he is signing this Amended Agreement voluntarily and of his own free will.

                                      -5-

<PAGE>   6


         IN WITNESS WHEREOF, this parties hereto have executed this Amended
Agreement as of the day and year first written above.

                                       ORBCOMM Global, L.P.

                                       By:
                                             ___________________________________
                                             Name:  Scott L. Webster
                                             Title:  Chairman and CEO

                                       _________________________________________
                                       Robert F. Latham


                                      -6-