AMERICAN MOBILE SATELLITE CORP
SC 13D, 1999-10-18
COMMUNICATIONS SERVICES, NEC
Previous: BIG ENTERTAINMENT INC, PRE 14A, 1999-10-18
Next: MACROMEDIA INC, S-8, 1999-10-18





                                                                    OMB APPROVAL
                                                           OMB Number: 3235-0145
                                                        Expires: August 31, 1999
                                                        Estimated average burden
                                                         hours per form....14.90


================================================================================



                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                  SCHEDULE 13D

                    Under the Securities Exchange Act of 1934

                           (Amendment No. _________)*

                        XM Satellite Radio Holdings Inc.
                        --------------------------------
                                (Name of Issuer)

                 Class A Common Stock, par value $.01 per share
- --------------------------------------------------------------------------------
                         (Title of Class of Securities)

                                   983759 10 1
- --------------------------------------------------------------------------------
                                 (CUSIP Number)

            Randy S. Segal, Senior Vice President and General Counsel
                      American Mobile Satellite Corporation
                            10802 Parkridge Boulevard
                                Reston, VA 20191
- --------------------------------------------------------------------------------
                  (Name, Address and Telephone Number of Person
               Authorized to Receive Notices and Communications)

                                 October 8, 1999
- --------------------------------------------------------------------------------
             (Date of Event which Requires Filing of this Statement)

If the filing person has previously  filed a statement on Schedule 13G to report
the  acquisition  which is the subject of this  Schedule 13D, and is filing this
schedule because of ss.ss. 240.13d-1(e),  240.13(d)-1(f) or 240.13d-1(g),  check
the following box |_|.

Note:  Schedules  filed in paper format shall include a signed original and five
copies of the schedule,  including all  exhibits.   See ss.  240.13d-7 for other
parties to whom copies are to be sent.

*The  remainder of this cover page shall be filled out for a reporting  person's
initial filing on this form with respect to the subject class of securities, and
for  any  subsequent   amendment   containing   information  which  would  alter
disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the  Securities  Exchange  Act of
1934 ("Act") or otherwise  subject to the liabilities of that section of the Act
but  shall be  subject  to all other  provisions  of the Act  (however,  see the
Notes).

Potential persons who are to respond to the collection of information  contained
in this form are not  required to respond  unless the form  displays a currently
valid OMB control number.


<PAGE>


                                  SCHEDULE 13D
<TABLE>
<CAPTION>

- --------------------------------------------------------------------------------
CUSIP No.  983759 10 1                                              13D - Page 2
- --------------------------------------------------------------------------------

<S>        <C>
1          NAME OF REPORTING PERSON:  American Mobile Satellite Corporation
           S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON:  93-0976127
- --------------------------------------------------------------------------------
2          CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
                                                                         (a) |_|
                                                                         (b) |_|
- --------------------------------------------------------------------------------
3          SEC USE ONLY

- --------------------------------------------------------------------------------
4          SOURCE OF FUNDS*:           WC, OO

- --------------------------------------------------------------------------------
5          CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
           ITEMS 2(d) or 2(e):             |_|
- --------------------------------------------------------------------------------
6          CITIZENSHIP OR PLACE OF ORGANIZATION:             Delaware
- --------------------------------------------------------------------------------

                           7            SOLE VOTING POWER:       18,072,176
        NUMBER OF
          SHARES        --------------------------------------------------------
       BENEFICIALLY
         OWNED BY          8            SHARED VOTING POWER:              0
           EACH
        REPORTING       --------------------------------------------------------
          PERSON
           WITH            9            SOLE DISPOSITIVE POWER:  18,072,176

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

                          10            SHARED DISPOSITIVE POWER:         0
- --------------------------------------------------------------------------------

11         AGGREGATE AMOUNT BENEFICIALLY OWNED
           BY EACH REPORTING PERSON:    18,072,176

- --------------------------------------------------------------------------------
12         CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11)
           EXCLUDES CERTAIN SHARES*

- --------------------------------------------------------------------------------
13         PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11):        41.0%

- --------------------------------------------------------------------------------
14         TYPE OF REPORTING PERSON*:   CO

- --------------------------------------------------------------------------------
</TABLE>


                      *SEE INSTRUCTIONS BEFORE FILLING OUT!
          INCLUDE BOTH SIDES OF THE COVER PAGE, RESPONSES TO ITEMS 1-7
      (INCLUDING EXHIBITS) OF THE SCHEDULE, AND THE SIGNATURE ATTESTATION.


<PAGE>

                                                                    13D - Page 3


Item 1.           Security and Issuer

         This Statement  relates to the Class A common stock, par value $.01 per
share  ("Class A  Stock"),  of XM  Satellite  Radio  Holdings  Inc.,  a Delaware
corporation (the "Issuer"). The Issuer's principal executive offices are located
at 1250 23rd Street, N.W., Washington, DC 20037-1100.


Item 2.           Identity and Background

         This Statement is filed by American  Mobile  Satellite  Corporation,  a
Delaware corporation ("American Mobile").  American Mobile's business address is
10802 Parkridge Boulevard, Reston, Virginia 20191-5416.

         American Mobile is a nationwide provider of wireless data, dispatch and
voice communications services.

         Prior to October 8, 1999,  American  Mobile owned  6,689,250  shares of
Class B common  stock,  par value $.01 per share (the  "Class B Stock"),  of the
Issuer,  which  shares  constituted  substantially  all of the  then-outstanding
voting stock of the Issuer.  On October 8, 1999, the Issuer completed an initial
public  offering  of  10,000,000  shares of Class A Stock (the  "Offering").  As
described  under  Item  4  below,  upon  completion  of  the  Offering,  certain
outstanding  convertible  debt securities of the Issuer owned by American Mobile
converted into an aggregate of 11,182,926  shares of Class B Stock.  As a result
of this conversion, as of October 8, 1999, American Mobile owned an aggregate of
17,872,176 shares of Class B Stock of the Issuer.

         The Class B Stock may be converted, on a one-for-one basis, into shares
of Class A Stock under certain  circumstances,  as described under Item 4 below.
Class B Stock is substantially  similar to Class A Stock, except that each share
of Class B Stock is entitled to three votes,  while Class A Stock is entitled to
one vote per share.

         In  addition  to the Class B Stock  described  above,  American  Mobile
purchased  200,000  shares of Class A Stock on October  8, 1999,  as part of the
Offering.

         This Statement  covers the 200,000 shares of Class A Stock purchased by
American Mobile on October 8, 1999, as well as the 17,872,176  shares of Class B
Stock owned by American  Mobile as of such date.  (Collectively,  such shares of
Class A Stock and Class B Stock are sometimes  referred to in this  Statement as
the "Securities.")

         Information  with respect to the  executive  officers and  directors of
American Mobile,  including name, business address, present principal occupation
or employment,  and the name,  principal business and address of any corporation
or other  organization in which such  employment is conducted,  is listed on the
schedule attached hereto as Annex A, which is incorporated herein by reference.

         None of American  Mobile nor, to the best of its knowledge,  any of its
executive  officers or directors has, during the last five years, been convicted
in a criminal proceeding  (excluding traffic violations or similar misdemeanors)
or been party to a civil  proceeding  of a judicial  or  administrative  body of
competent  jurisdiction and as a result of such proceedings was or is subject to
a judgment, decree or final order enjoining future violations of, or prohibiting
or mandating  activities subject to, federal or state securities laws or finding
any violation with respect to such laws.



<PAGE>


                                                                    13D - Page 4


         To the best knowledge of American Mobile, all of its executive officers
and directors are United States citizens.


Item 3.           Source and Amount of Funds or Other Consideration


         Shares of Class B Stock

         The 17,872,176  shares of Class B Stock owned by American  Mobile as of
the date of this  Statement  were  acquired  for various  consideration,  over a
period of several years, prior to the consummation of the Offering, and prior to
the Issuer becoming  subject to Section 12(g) of the Securities  Exchange Act of
1934,  as amended  (the  "Exchange  Act").  Set forth  below is a summary of the
consideration  paid by American Mobile for the shares of Class B Stock currently
owned by it.

         In May 1997, American Mobile formed the Issuer and contributed $143,000
to the  Issuer  to  establish  the  Issuer's  original  application  for its FCC
license.  Also in 1997, American Mobile provided the Issuer with $1.5 million as
a capital  contribution.  The funds used for these  contributions  came from the
working capital of American Mobile. At the same time in 1997, WorldSpace,  Inc.,
a Maryland corporation unrelated to American Mobile ("WorldSpace"), acquired 20%
of the voting  stock in the  Issuer,  and was also  granted  certain  options to
acquire additional capital stock of the Issuer.  Between May 1997 and July 1999,
WorldSpace  provided  additional funds to the Issuer, in the form of both equity
investments and loans,  including loans  represented by notes  convertible  into
stock of the Issuer.

         In January 1999, American Mobile loaned the Issuer  approximately $21.4
million,  in  exchange  for  shares of  common  stock of the  Issuer  and a note
convertible into additional shares of common stock of the Issuer. The funds used
for this loan were borrowed by American  Mobile from Baron Asset Fund ("Baron"),
in exchange for a $21.5 million junior  subordinated  secured  exchangeable note
(the  "Baron  Note")  issued by  American  Mobile to  Baron.  The Baron  Note is
exchangeable,  under certain  circumstances  described under Item 4 below,  into
shares  of Class B Stock  owned by  American  Mobile.  The  Baron  Note  accrues
interest at the rate of 6% per annum,  with all interest payments deferred until
the maturity date, December 31, 2004. If the Baron Note is exchanged into shares
of Class A Stock pursuant to its terms, all interest accrued through the date of
such exchange will be extinguished.

         On July 7, 1999,  American  Mobile  acquired from XM Ventures,  a trust
established by WorldSpace,  all of WorldSpace's debt and equity interests in the
Issuer, other than a $75 million loan from WorldSpace to the Issuer, in exchange
for 8,614,244 shares of American Mobile's common stock, par value $.01 per share
(the  "Exchange  Transaction").  As a result of these  transactions,  WorldSpace
ceased to have any direct  equity or debt  interest in the Issuer.  Concurrently
with  this   transaction,   the  Issuer  issued  $250  million  of  subordinated
convertible  notes to several new strategic and financial  investors  other than
American  Mobile,  and the Issuer  used $75 million of the  proceeds  from these
notes to repay the outstanding loan payable to WorldSpace.

         Immediately after the Exchange Transaction,  the Issuer reorganized its
capital structure and the shares of common stock of the Issuer owned by American
Mobile were exchanged on a one-for-one  basis for shares of Class B Stock.  As a
result,  American Mobile owned 125 shares of Class B Stock of the Issuer,  which
constituted  100% of the  outstanding  Class B Stock,  and  which  were the only
shares of the  Issuer's  capital  stock then  outstanding.  Also as part of this
reorganization, certain of the debt interests acquired by American Mobile in the
Exchange  Transaction were exchanged for a single convertible note issued by the
Issuer, convertible into shares of the Issuer's Class B common stock.



<PAGE>


                                                                    13D - Page 5


         In September 1999, the Issuer effected a 53,514 for 1 stock split. As a
result,  the 125  shares of Class B Stock  then owned by  American  Mobile  were
exchanged for 6,689,250 shares of Class B Stock.

         On October 8, 1999,  upon the  completion of the  Offering,  all of the
convertible  notes  of the  Issuer  owned  by  American  Mobile  converted  into
11,182,926  shares  of Class B  Stock.  As a result  of this  conversion,  as of
October 8, 1999,  American  Mobile owned an aggregate  of  17,872,176  shares of
Class B Stock.


         Shares of Class A Stock

         American Mobile purchased 200,000 shares of Class A Stock of the Issuer
in the Offering.  The consideration  paid by American Mobile was $2,400,000,  or
$12.00 per share,  which was the initial public  offering price in the Offering.
The source of such consideration was cash on hand.

         To the best knowledge of American Mobile, the funds used by the persons
listed in Annex A to purchase  the shares of Class A Stock  specified  in Item 5
below came from personal savings of such persons.


Item 4.           Purpose of Transaction

         The 17,872,176  shares of Class B Stock owned by American  Mobile as of
the date of this  Statement  were  acquired  for various  consideration,  over a
period of several years, prior to the consummation of the Offering, and prior to
the  Issuer  becoming  subject  to  Section  12(g) of the  Exchange  Act.  These
transactions  are described in detail in Item 3 above.  American  Mobile was the
initial,  sole  stockholder of the Issuer.  The  subsequent  changes in American
Mobile's ownership interest in the Issuer, prior to the Offering,  were effected
to maximize the potential  future value to American Mobile and its  stockholders
of its interest in the Issuer.

         American  Mobile  purchased  200,000  shares  of  Class A Stock  in the
Offering  in order to  demonstrate  its  commitment  to the  Issuer's  long-term
business plans and objectives,  and because  American Mobile  concluded that the
initial  public  offering  price  of  the  Offering  represented  an  attractive
opportunity to increase its equity position in the Issuer.  American Mobile also
noted that several of the other  significant  equity  stakeholders in the Issuer
elected to similarly participate in the Offering.

         Certain of  American  Mobile's  rights  with  respect to the Issuer are
governed by a shareholders'  agreement by and among the Issuer, American Mobile,
and certain other  significant  shareholders  of the Issuer (the  "Shareholders'
Agreement").  Pursuant to the Shareholders' Agreement, American Mobile currently
has four  representatives  on the Board of Directors of the Issuer, and also has
the  right  to  approve  one of the two  independent  members  of the  Board  of
Directors of the Issuer.  Certain other material provisions of the Shareholders'
Agreement are described in more detail in Item 6 below.

         There are certain  restrictions on American Mobile's ability to sell or
otherwise transfer the Securities. Under the Shareholders' Agreement, except for
affiliated  transactions,  American  Mobile may not  transfer any of its Class A
Stock or Class B Stock until the earlier of the date on which the Issuer  begins
commercial  operations,  or  October  8,  2000.  Shares  of  Class B  Stock  are
transferable  only upon  conversion into shares of Class A Stock and, in certain
circumstances  as described  below,  to Baron,  which can transfer its shares of
Class B Stock only upon conversion into shares of Class A Stock.



<PAGE>


                                                                    13D - Page 6


         In  addition,  American  Mobile has signed a "lock-up"  agreement  with
Bear,  Stearns  &  Co.  Inc.  and  Donaldson,   Lufkin  &  Jenrette   Securities
Corporation, the lead underwriters for the Offering. Pursuant to this agreement,
American Mobile has agreed not to sell, offer to sell, contract to sell, pledge,
hypothecate,  sell any option or contract to purchase or  otherwise  transfer or
dispose of,  directly or  indirectly,  any shares of Class A Stock or securities
convertible  into Class A Stock,  for a period of 180 days  after the  effective
date of the registration statement filed by the Issuer in the Offering.

         The  Securities  are also  subject to  certain  pledge  agreements  and
related contingencies, as described below.

         American Mobile has granted a first priority lien on all of the 200,000
shares  of Class A Stock  owned by it, as well as  16,557,262  shares of Class B
Stock owned by it, to its bank lenders, to secure American Mobile's  obligations
under its term loan facility. American Mobile has also granted a second priority
lien  on  all  such  shares  to  Hughes   Electronics   Corporation,   Singapore
Telecommunications,  Ltd.,  and Baron Capital  Partners,  L.P., as guarantors of
American  Mobile's  term and  revolving  loan  facilities,  to  secure  American
Mobile's  obligations  under an  agreement  that  requires  American  Mobile  to
reimburse  such  guarantors in the event the guarantors are required to make any
payment under the bank facility guarantees.

         In  addition,  American  Mobile  has  granted  a lien on the  remaining
1,314,914  shares  of  Class B Stock  owned by it to  Baron  to  secure  certain
obligations of American  Mobile  pursuant to the Baron Note.  Under the terms of
the Baron Note,  commencing on January 15, 2000, Baron may elect to exchange the
principal amount of the Baron Note (or any portion thereof) into an aggregate of
1,314,914  shares  of Class B Stock of the  Issuer  owned  by  American  Mobile.
American  Mobile  has  granted  Baron a lien on such  shares of Class B Stock to
secure its obligation to Baron to deliver the required number of shares of Class
B Stock upon exchange of the Baron Note.

         Except as described  above in this Item 4 and below in Item 6, American
Mobile does not have any plans or  proposals  that relate to or would  result in
any of the actions or events  specified  in clauses (a) through (j) of Item 4 of
Schedule 13D.  Notwithstanding  the foregoing,  and subject to the  restrictions
under the Shareholders'  Agreement,  American Mobile may determine to change its
investment intent with respect to the Issuer at any time in the future. American
Mobile intends to vote its shares as it deems  appropriate from time to time. In
determining from time to time whether to sell its shares of the Issuer's Class A
Stock (and in what amounts) or to retain such shares,  American Mobile will take
into consideration such factors as it deems relevant, including the business and
prospects of the Issuer,  anticipated future developments concerning the Issuer,
existing and anticipated  market conditions from time to time,  general economic
conditions,  regulatory matters,  and other opportunities  available to American
Mobile.  American Mobile reserves the right to acquire additional  securities of
the Issuer in the open market, in privately  negotiated  transactions (which may
be with the Issuer or with third  parties) or otherwise,  to dispose of all or a
portion of its holdings of  securities  of the Issuer or to change its intention
with respect to any or all of the matters referred to in this Item 4.

         To the best knowledge of American Mobile, all shares identified in Item
5 below as beneficially owned by persons listed in Annex A were acquired by such
persons for investment purposes.  Such persons may buy or sell shares of Class A
Stock in the future as they deem  appropriate,  but,  to the best  knowledge  of
American Mobile, and except as otherwise  indicated herein, such persons have no
present  plan or  proposal  that  relates to or would  result in the  actions or
events specified in clauses (a) through (j) of Item 4 of Schedule 13D.




<PAGE>


                                                                    13D - Page 7


Item 5.           Interest in Securities of the Issuer


         After  giving  effect to the issuance of  10,000,000  shares of Class A
Stock by the  Issuer in the  Offering,  and  based on  information  provided  to
American  Mobile by the Issuer (the  "Available  Data"),  there were  26,194,471
shares of Class A Stock of the Issuer outstanding on October 8, 1999.

         As of October 8,  1999,  American  Mobile  beneficially  owned  200,000
shares of Class A Stock,  which  represents  approximately  0.76% of the Class A
Stock outstanding.  Subject to the restrictions and agreements described in Item
4 above,  American Mobile has the sole power to vote (or to direct the vote) and
the sole  power to  dispose  (or to direct  the  disposition)  of these  shares.
American Mobile acquired these shares in the Offering.

         American Mobile also  beneficially  owns  17,872,176  shares of Class B
Stock.  The  Issuer's  Class B Stock  is  convertible  into  Class A Stock  on a
one-for-one  basis. Class B Stock is entitled to three votes for each share, and
Class A Stock is  entitled  to one vote per share.  Because the Class B Stock is
currently  convertible  into Class A Stock,  under Rule 13d-3 under the Exchange
Act,  American Mobile is deemed to beneficially  own the shares of Class A Stock
that can be  acquired  upon  conversion  of the  Class B Stock.  Subject  to the
restrictions and agreements  described in Item 4 above,  American Mobile has the
sole power to vote (or to direct the vote) and the sole power to dispose  (or to
direct the disposition) of these shares.

         On a fully converted basis, as of the date of this Statement,  American
Mobile is deemed to beneficially own an aggregate of 18,072,176  shares of Class
A Stock,  which  represents  approximately  41.0% of the Issuer's  Class A Stock
outstanding  after  issuance  of the  17,872,176  shares  of Class A Stock  upon
conversion of the Class B Stock owned by American Mobile.

         As described above in Item 4, 16,557,262 of the shares of Class B Stock
owned by American  Mobile,  and all of the 200,000 shares of Class A Stock owned
by  American  Mobile,   are  pledged  to  American  Mobile's  bank  lenders  and
guarantors, to secure American Mobile's obligations under its term and revolving
credit facilities.  In addition,  1,314,914 of the shares of Class B Stock owned
by American Mobile are pledged to Baron to secure American Mobile's  obligations
under the Baron Note.

         To the best knowledge of American Mobile,  only the following executive
officers and  directors of American  Mobile  beneficially  own shares of Class A
Stock of the Issuer:

<TABLE>
<S>                                                               <C>
         Robert L. Goldsmith                                       3,600  shares
         Billy J. Parrott                                          6,000  shares
         Gary M. Parsons                                          24,716  shares
         Walter V. Purnell, Jr.                                   10,000  shares
         Andrew A. Quartner                                       15,000  shares
         Randy S. Segal                                           26,757  shares
         Jack A. Shaw                                             26,757  shares
</TABLE>

         In each  case,  the  number  of  shares  of Class A Stock  owned by the
persons listed above  constitutes less than 1% of the outstanding  Class A Stock
of the Issuer.  Of the shares set forth above,  all such shares are beneficially
owned directly or indirectly by the persons named, except that all of the shares
indicated for each of Ms. Segal and Mr. Shaw  represent  shares of Class A Stock
which such  persons  have the right to  acquire  pursuant  to options  which are
exercisable  currently,  and 10,000 of the shares of Class A Stock indicated for
Mr. Parsons are owned jointly by Mr.  Parsons and his wife. In addition,  14,716
of the shares of Class A Stock owned by Mr.  Parsons are subject to the Issuer's
right to repurchase such shares if Mr. Parsons' service as Chairman of the Board
of Directors of the Issuer ends


<PAGE>


                                                                    13D - Page 8


prior to the  first  anniversary  of the  date the  shares  were  issued  to Mr.
Parsons. Mr. Parsons also owns options exercisable for 267,570 shares of Class A
Stock,  which options are not  exercisable  within 60 days.  Except as set forth
above,  to the best  knowledge  of  American  Mobile,  no  executive  officer or
director of American Mobile beneficially owns any shares of Class A Stock of the
Issuer  or has the right to  acquire  such  shares.  American  Mobile  expressly
disclaim  beneficial  ownership of the shares of Class A Stock shown as owned by
the persons identified in the above table.

         American  Mobile may be deemed to comprise a group  (within the meaning
of Section  13(d)(3) of the Exchange Act) with the following  entities by virtue
of  the  Shareholders'  Agreement:  (1)  General  Motors  Corporation  ("General
Motors");  (2)  DIRECTV  Enterprises,   Inc.  ("DIRECTV");   (3)  Clear  Channel
Investments,  Inc.  ("Clear  Channel");  (4) Columbia XM Radio Partners,  L.L.C.
("Columbia");  (5)  Telcom-XM  Investors,  L.L.C.  ("Telcom");  and (6)  Madison
Dearborn Capital Partners III, L.P. ("M-D Capital  Partners"),  Madison Dearborn
Special Equity III, L.P. ("M-D Special  Equity"),  and Special  Advisors Fund I,
L.L.C.  ("Special  Advisors,"  and,  together with M-D Capital  Partners and M-D
Special  Equity,  "Madison  Dearborn").   American  Mobile  expressly  disclaims
beneficial  ownership  of the  shares  of  Class A Stock of the  Issuer  held by
General Motors, DIRECTV, Clear Channel,  Columbia,  Telcom, or Madison Dearborn,
and the filing of this Statement by American Mobile shall not be construed as an
admission by American  Mobile that it is, for  purposes of Section  13(d) of the
Exchange Act, the beneficial  owner of any of the shares of Class A Stock of the
Issuer held by General  Motors,  DIRECTV,  Clear  Channel,  Columbia,  Telcom or
Madison Dearborn.

         Based solely upon the Available Data, American Mobile believes that, as
of October 8, 1999 (the closing date of the Offering),  General Motors, DIRECTV,
Clear Channel,  Columbia,  Telcom and Madison  Dearborn  beneficially  owned the
number of shares of Class A Stock of the  Issuer  set forth in the table  below,
constituting  in each case that  percentage  of the Class A Stock of the  Issuer
outstanding on October 8, 1999 set forth in the table.
<TABLE>
<CAPTION>

    Name of Beneficial Owner        Number of Shares             Percentage

<S>                                    <C>        <C>               <C>
    General Motors                     11,106,504 (1)               30.03%
    DIRECTV                             5,553,252 (2)               17.58%
    Clear Channel                       8,329,877                   31.80%
    Columbia                            2,776,626                   10.60%
    Telcom                              2,696,626                   10.29%
    M-D Capital Partners                2,702,200                   10.31%
    M-D Special Equity                     58,247                        *
    Special Advisors                       16,179                        *
    ------------------
    *  Less than 1%
</TABLE>

     (1) Includes 10,786,504 shares of Class A Stock issuable upon conversion of
     Series A convertible preferred stock of the Issuer,  5,393,252 of which are
     owned by DIRECTV,  an indirect  subsidiary of General Motors. The shares of
     Class  A  Stock  issuable  upon  conversion  of the  Series  A  convertible
     preferred  stock were deemed to be outstanding for the purpose of computing
     the  percentage of the Class A Stock owned by General  Motors,  but not for
     the purpose of computing the percentage of Class A Stock owned by any other
     person.

     (2) Includes  5,393,252 shares of Class A Stock issuable upon conversion of
     Series A convertible  preferred stock of the Issuer.  The shares of Class A
     Stock issuable upon conversion of the Series A convertible  preferred stock
     were deemed to be  outstanding  for the purpose of computing the percentage
     of the Class A Stock owned by DIRECTV, but not for the purpose of computing
     the percentage of Class A Stock owned by any other person.



<PAGE>

                                                                    13D - Page 9


         Except for the transactions reported in this Statement, American Mobile
has not engaged in any other  transactions  in the Issuer's Class A Stock within
the past 60 days.

         To the best  knowledge  of American  Mobile,  no  executive  officer or
director has effected any  transactions  in the Class A Stock within the past 60
days,  except that the following  persons  purchased shares of Class A Stock, in
the amounts indicated below, in the Offering,  at a purchase price of $12.00 per
share:

<TABLE>
<S>                                                              <C>
         Robert L. Goldsmith                                       3,600  shares
         Billy J. Parrott                                          6,000  shares
         Gary M. Parsons                                         10,000   shares
         Walter V. Purnell, Jr.                                  10,000   shares
         Andrew A. Quartner                                      15,000   shares
</TABLE>

         A trust for the  benefit  of the  minor  children  of Gary M.  Parsons,
Chairman  of the Board of  Directors  of  American  Mobile and the  Issuer,  has
acquired a minority  membership  interest in each of  Columbia  and Telcom and a
minority  participatory interest in each of M-D Capital Partners and M-D Special
Equity. Mr. Parsons disclaims beneficial ownership of these interests.

         Based solely upon the information set forth in the Issuer's Prospectus,
dated October 5, 1999, and on the Available Data, American Mobile believes that:
(1) on October 8, 1999,  each of General  Motors and DIRECTV  acquired  from the
Issuer  in a  private  placement  5,393,252  shares  of the  Issuer's  Series  A
convertible  preferred  stock upon  conversion of $50,000,000  principal  amount
(plus accrued interest) of convertible  subordinated  notes previously issued to
each of General  Motors and  DIRECTV by the  Issuer,  at a  conversion  price of
approximately  $9.52 per share,  and (2) on  October  8,  1999,  each of General
Motors and DIRECTV  acquired 160,000 shares of the Issuer's Class A Stock in the
Offering,  at a purchase price of $12.00 per share,  the initial public offering
price of the Class A Stock.

         Based solely upon the information set forth in the Issuer's Prospectus,
dated October 5, 1999, and on the Available Data, American Mobile believes that:
(1) on October  8, 1999,  Clear  Channel  acquired  from the Issuer in a private
placement  8,089,877  shares of Class A Stock  upon  conversion  of  $75,000,000
principal  amount (plus  accrued  interest) of a convertible  subordinated  note
previously  issued to Clear  Channel by the  Issuer,  at a  conversion  price of
approximately  $9.52 per  share,  and (2) on  October  8,  1999,  Clear  Channel
acquired  240,000  shares of the Issuer's  Class A Stock in the  Offering,  at a
purchase  price of $12.00 per share,  the initial  public  offering price of the
Class A Stock.

         Based solely upon the information set forth in the Issuer's Prospectus,
dated October 5, 1999, and on the Available Data, American Mobile believes that:
(1) on October 8, 1999,  each of Columbia and Telcom acquired from the Issuer in
a  private  placement  2,696,626  shares  of Class A Stock  upon  conversion  of
$25,000,000 principal amount (plus accrued interest) of convertible subordinated
notes  previously  issued to each of  Columbia  and Telcom by the  Issuer,  at a
conversion price of  approximately  $9.52 per share, and (2) on October 8, 1999,
Columbia  acquired  80,000 shares of the Issuer's Class A Stock in the Offering,
at a purchase price of $12.00 per share,  the initial  public  offering price of
the Class A Stock.

         Based solely upon the information set forth in the Issuer's Prospectus,
dated October 5, 1999, and on the Available Data, American Mobile believes that:
(1) on October 8,  1999,  M-D  Capital  Partners  acquired  from the Issuer in a
private  placement  2,622,200  shares  of  Class  A  Stock  upon  conversion  of
$24,310,000 principal amount (plus accrued interest) of convertible subordinated
notes previously  issued to M-D Capital Partners by the Issuer,  at a conversion
price of approximately  $9.52 per share, and (2) on October 8, 1999, M-D Capital
Partners  acquired  80,000 shares of the Issuer's Class A Stock in the Offering,
at a purchase price of $12.00 per share,  the initial  public  offering price of
the Class A Stock.


<PAGE>


                                                                   13D - Page 10



         Based solely upon the information set forth in the Issuer's Prospectus,
dated October 5, 1999, and on the Available Data,  American Mobile believes that
on October 8, 1999,  M-D Special  Equity  acquired  from the Issuer in a private
placement  58,247 shares of Class A Stock upon conversion of $540,000  principal
amount (plus accrued  interest) of  convertible  subordinated  notes  previously
issued  to  M-D  Special  Equity  by  the  Issuer,  at  a  conversion  price  of
approximately $9.52 per share.

         Based solely upon the information set forth in the Issuer's Prospectus,
dated October 5, 1999, and on the Available Data,  American Mobile believes that
on October  8,  1999,  Special  Advisors  acquired  from the Issuer in a private
placement  16,179 shares of Class A Stock upon conversion of $150,000  principal
amount (plus accrued  interest) of  convertible  subordinated  notes  previously
issued to Special Advisors by the Issuer, at a conversion price of approximately
$9.52 per share.

         American  Mobile does not know of any other person  having the right to
receive or the power to direct the receipt of  dividends  from,  or the proceeds
from the sale of, the shares of Class A Stock of the Issuer  beneficially  owned
by American Mobile.



Item 6. Contracts, Arrangements, Understandings or Relationships with Respect to
Securities of the Issuer


         Shareholders' Agreement

         Set forth below is a description of certain material  provisions of the
Shareholders' Agreement:

         Governance Provisions. The Issuer's board of directors consists of nine
members,  four of whom are selected by American  Mobile,  including the Issuer's
Chairman and President and Chief Executive  Officer,  three of whom are selected
by certain other shareholders,  and two independent directors,  one of whom must
be approved by American  Mobile,  and one of whom must be approved by a majority
of certain  other  shareholders.  Following  receipt of  approval  of the FCC to
transfer  control  of the  Issuer  from  American  Mobile to a diffuse  group of
shareholders,  the  Issuer's  board of directors  will consist of nine  members,
three of whom  will be  selected  by  American  Mobile,  three  of whom  will be
selected  by  certain  other  shareholders,  two of  whom  will  be  independent
directors of recognized  industry  experience and stature whose nominations must
be approved by American Mobile and a majority of certain other shareholders, and
one of whom will be the Issuer's  President  and Chief  Executive  Officer.  The
foregoing board rights are subject to the parties to the Shareholders' Agreement
maintaining  their original  investment or certain minimum share  percentages in
the Issuer.

         Conversion  of Class B Stock to Class A Stock.  The Class B Stock owned
by American Mobile is convertible into Class A Stock, on a one-for-one basis, at
any time at American Mobile's discretion.  In addition,  under the Shareholders'
Agreement, the holders of a majority of the outstanding shares of Class A Stock,
which must include at least 20% of the public holders of the Class A Stock,  may
require  conversion by American  Mobile.  This  conversion will not be effected,
however,  if the FCC does not approve the transfer of control of the Issuer from
American Mobile to a diffuse group of shareholders.



<PAGE>


                                                                   13D - Page 11


         Non-Competition.  American  Mobile has  agreed not to compete  with the
Issuer in the  satellite  radio  business  in the  United  States for so long as
American  Mobile holds 5% of the Issuer's common stock and for a period of three
years  following any transfer which results in American  Mobile owning less than
5% of the Issuer's common stock.

         Restrictions  on Transfer of Securities.  As described in Item 4 above,
except for affiliated transactions,  American Mobile may not transfer any of its
Class A Stock or Class B Stock until the earlier of the date on which the Issuer
begins  commercial  operations,  or October 8, 2000. Shares of Class B Stock are
transferable  only upon  conversion into shares of Class A Stock and, in certain
circumstances  as  described in Item 4 above,  to Baron,  which can transfer its
shares only upon conversion into shares of Class A Stock.


         Registration Rights Agreement

         In addition to the contracts and agreements described above and in Item
4 above,  American  Mobile has certain  registration  rights with respect to the
Securities, pursuant to a registration rights agreement, dated July 7, 1999 (the
"Registration  Rights  Agreement"),  by and among the Issuer,  American  Mobile,
Baron, and certain other  stockholders  named therein.  Commencing July 7, 2000,
American Mobile and the other  stockholders  that are party to the  Registration
Rights Agreement are entitled to demand registration with respect to their Class
A Stock, including shares issuable upon conversion of other securities. American
Mobile is entitled to make two demands. These rights are subject to the Issuer's
right to defer the timing of a demand registration and an underwriters' right to
cut back shares in an underwritten  offering.  In certain  instances if a demand
registration  is cut back by more than 75% of the  number  of shares  originally
requested to be  registered,  then the party  requesting  registration  shall be
entitled to one additional  demand  registration  request.  In addition to these
demand  rights,  following the Issuer's  commencement  of commercial  operation,
parties to the  Registration  Rights  Agreement may request  registration  of at
least  $25.0  million  of  Class A Stock.  Parties  to the  Registration  Rights
Agreement  also  have  rights  to  include  their  Class A Stock  in  registered
offerings initiated by the Issuer, other than an offering for high yield debt.

         Other than the Shareholders'  Agreement,  Registration Rights Agreement
and the other  agreements  described  in Item 4 above,  there are no  contracts,
arrangements,  understandings,  or relationships  between American Mobile or, to
the best of its knowledge, any executive officer or director of American Mobile,
and any other person with respect to any securities of the Issuer, including any
contract, arrangement,  understanding or relationship concerning the transfer or
the voting of any securities of the Issuer,  finder's fees, joint ventures, loan
or option  arrangements,  puts or calls,  guarantees  of  profits,  division  of
profits or loss, or the giving or withholding of proxies.


Item 7.           Material to be Filed as Exhibits

Exhibit 1         Shareholders'  Agreement,  dated  as  of  July 7, 1999, by and
                  among the Issuer,  American  Mobile,  Baron Asset Fund,  Clear
                  Channel  Investments,  Inc., Columbia XM Radio Partners,  LLC,
                  DIRECTV,  Inc., General Motors  Corporation,  Madison Dearborn
                  Capital  Partners  III,  L.P.,  Special  Advisors Fund I, LLC,
                  Madison  Dearborn  Special  Equity III,  L.P.,  and Telcom- XM
                  Investors,  L.L.C.  (incorporated by reference to Exhibit 99.2
                  to American Mobile's registration  statement on Form S-3 (File
                  No. 333-81459)).

Exhibit 2         Registration  Rights  Agreement,  dated  July 7, 1999, by  and
                  among the Issuer, American Mobile, the Baron Asset Fund series
                  of Baron Asset Fund,  and the holders of Series A subordinated
                  convertible  notes  of the  Issuer  named  in  such  agreement
                  (incorporated by


<PAGE>

                                                                   13D - Page 12


                  reference to Exhibit  99.3  to  American Mobile's registration
                  statement on Form S-3 (File No. 333-81459)).

Exhibit 3         $21,500,000 Junior Subordinated  Secured  Exchangeable Note,
                  dated  January 15,  1999,  issued by American  Mobile to Baron
                  Asset Fund (the "Baron Note") (filed herewith).

Exhibit 3a        Amendment, dated July 7, 1999, to the Baron Note (filed
                  herewith).



<PAGE>

                                                                   13D - Page 13


                                    SIGNATURE


                  After  reasonable  inquiry and to the best of my knowledge and
belief,  I certify  that the  information  set forth in this  Statement is true,
complete and correct.


                                      AMERICAN MOBILE SATELLITE CORPORATION



                                      By:      /s/ Randy S. Segal

                                      Name:    Randy S. Segal
                                      Title:   Senior Vice President and General
                                               Counsel


Date:    October 18, 1999





<PAGE>


                                                                   13D - Page 14


                                     ANNEX A


DIRECTORS OF AMERICAN MOBILE


<TABLE>
<CAPTION>
                                       Present Principal
Name and Business Address               Occupation or Employment
- -------------------------               ------------------------


<S>                                     <C>
Douglas I. Brandon                      Vice President - External Affairs & Law
AT&T Wireless Services, Inc.            AT&T Wireless Services, Inc.
1150 Connecticut Avenue, N.W.
4th Floor
Washington, DC  20036

Billy J. Parrott                        President and Chief Executive Officer
Antifire, Inc.                          Antifire, Inc.
276 Fifth Avenue
Suite 301
New York, NY  10001

Gary M. Parsons                         Chairman of the Board of Directors
American Mobile Satellite Corporation   American Mobile Satellite Corporation
10802 Parkridge Boulevard
Reston, VA  20191

Walter V. Purnell, Jr.                  President and Chief Executive Officer
American Mobile Satellite Corporation   American Mobile Satellite Corporation
10802 Parkridge Boulevard
Reston, VA  20191

Andrew A. Quartner                      Corporate Counsel
Nextlink Communications, Inc.           Nextlink Communications, Inc.
1730 Rhode Island Avenue, N.W.
Suite 1000
Washington, DC  20036

Jack A. Shaw                            Chairman and Chief Executive Officer
Hughes Network Systems                  Hughes Network Systems
11717 Exploration Lane
Germantown, MD  20876
</TABLE>


<PAGE>


                                                                   13D - Page 15



EXECUTIVE OFFICERS OF AMERICAN MOBILE


<TABLE>
<CAPTION>

Name and Business Address
(all business addresses are               Present Principal
American Mobile Satellite Corporation     Occupation or Employment
10802 Parkridge Boulevard                 (all with American Mobile
Reston, VA  20191)                        Satellite Corporation)
- ----------  -----                         ----------------------

<S>                                       <C>
Robert L. Goldsmith                       Executive Vice President and
                                          Chief Operating Officer

Gary M. Parsons                           Chairman of the Board

Walter V. Purnell, Jr.                    President and Chief Executive Officer

Randy S. Segal                            Senior Vice President and
                                          General Counsel

W. Bartlett Snell                         Senior Vice President and Chief
                                          Financial Officer

</TABLE>


<PAGE>



                                                                       EXHIBIT 3

                              JUNIOR SUBORDINATED SECURED EXCHANGEABLE NOTE


THIS NOTE HAS NOT BEEN  REGISTERED  UNDER THE SECURITIES ACT OF 1933, AS AMENDED
(THE  "SECURITIES  ACT") OR ANY APPLICABLE  STATE SECURITIES LAWS. IT MAY NOT BE
SOLD OR OFFERED FOR SALE IN THE ABSENCE OF AN EFFECTIVE  REGISTRATION  STATEMENT
UNDER THE SECURITIES ACT AND COMPLIANCE  WITH SUCH STATE  SECURITIES  LAWS OR AN
OPINION OF COUNSEL  SATISFACTORY  TO THE COMPANY THAT SUCH  REGISTRATION  AND/OR
COMPLIANCE IS NOT REQUIRED.

$21,500,000
                                                                January 15, 1999

     FOR VALUE  RECEIVED,  American  Mobile  Satellite  Corporation,  a Delaware
corporation (the "Company"), promises to pay to the order of Baron Asset Fund on
behalf of The Baron Asset Fund Series, or its registered assigns (the "Holder"),
the principal sum of  $21,500,000  or such lesser amount as shall then equal the
outstanding  principal  amount  hereof,  together with interest from the date of
issuance of this Note on the unpaid principal  balance hereof at a rate equal to
six percent (6%) per annum,  computed on the basis of the actual  number of days
elapsed and a year of 365 days. All unpaid principal,  together with any accrued
but  unpaid  interest  and other  amounts  payable  hereunder,  shall be due and
payable on September 30, 2006 (the "Maturity Date"). Interest on this Note shall
accrue on a  quarterly  basis on January 1, April 1, July 1 and October 1, (each
an  "Interest  Accrual  Date") with the first such  Interest  Accrual Date being
April 1, 1999; provided, however, that right to accrued interest on this Note is
subject to Section 7(b) herein.

     This Note is issued pursuant to the Note Purchase  Agreement (the "Purchase
Agreement")  dated as of January  15,  1999 by and  between  the Company and the
Holder.

     The following is a statement of the rights of the Holder and the conditions
to which this Note is subject, and to which the Holder hereof, by the acceptance
of this Note, agrees:

         1.   Definitions. As used in this Note, the following capitalized terms
have the following meanings:

          (a) "Business  Day"  means any  day other than a  Saturday,  Sunday or
other day on which the national or state banks  located in the State of New York
are authorized to be closed.

          (b) "Exchange Price" has the meaning set forth in Section 7(a) hereof.

          (c) "Obligations"  means  the  principal,  interest and other  amounts
payable under this Note.

          (d) "Senior Debt" shall mean the  principal of (and premium,  if any),
unpaid  interest on and fees,  expenses,  costs of enforcement and other amounts
due in connection with (a) all outstanding indebtedness of the Company for money
borrowed  (other  than  this  Note) for the  payment  of which  the  Company  is
responsible  or liable,  or the  payment of which the  Company  has  guaranteed,
whether such  indebtedness  is  outstanding  as of the date hereof or thereafter
created,  incurred,  assumed  or  guaranteed  by  the  Company,  unless  in  the
instrument  creating  or  evidencing  the same or  pursuant to which the same is
outstanding it is specifically  provided that such  indebtedness is not superior
in right of payment to this Note,  (b) capital lease  obligations  determined in
accordance with generally accepted accounting principles,  (c) any obligation of
the Company to reimburse  banks  pursuant to letters of credit  extended by such
banks, advances made

                                       16

<PAGE>



by such  banks and other  credit  arrangements  entered  into with such banks in
connection  with tax-exempt  obligations  issued for the benefit of the Company,
and  (d)  renewals   extensions,   modifications  and  refundings  of  any  such
indebtedness or obligations,  provided however,  that Senior Debt shall not mean
the principal of (and premium,  if any), unpaid interest on and fees,  expenses,
costs  of  enforcement  and  other  amounts  due in  connection  with  any  such
indebtedness that is expressly subordinated to this Note.

          (e) "XM"  means XM  Satellite  Radio  Holdings,  Inc.,  a  corporation
organized under the laws of the State of Delaware.

          (f) "XM Common Stock" means the common stock of XM, having a par value
of $0.10 per share.

          (g) "XM  Convertible  Note" means the  Convertible  Note,  dated as of
January 15, 1999, for a principal amount of up to $806,050,  issued by XM to the
Company.

          (h) "XM Note Shares" means the shares of XM Common Stock issuable upon
exercise of the conversion rights under the XM Convertible Note.

          (i) "XM Owned  Shares"  means the  23.6502  shares of XM Common  Stock
owned by the Company.

         2.  Exchange  Event.  The  occurrence  of any of  the  following  shall
constitute an "Exchange Event" under this Note:

                  (a) Failure to Pay. The Company shall fail to pay (i) when due
any  principal  payment  on this  Note or (ii) any  interest  or  other  payment
required under the terms of this Note within five Business Days of its due date;

                  (b) Breaches of  Covenants.  The Company shall fail to observe
or to perform any other covenant,  obligation,  condition or agreement contained
in this Note, and such failure shall continue for 30 days.

                  (c)  Voluntary  Bankruptcy  or  Insolvency  Proceedings.   The
Company  shall  (i) apply  for or  consent  to the  appointment  of a  receiver,
trustee,  liquidator or custodian of itself or of all or a  substantial  part of
its  property,  (ii) be unable,  or admit in writing its  inability,  to pay its
debts generally as they mature,  (iii) make a general assignment for the benefit
of its or any of its  creditors,  (iv) be dissolved or  liquidated in full or in
part, (v) become insolvent (as such term may be defined or interpreted under any
applicable statute),  (vi) commence a voluntary case or other proceeding seeking
liquidation,  reorganization or other relief with respect to itself or its debts
under any bankruptcy, insolvency or other similar law now or hereafter in effect
or consent to any such relief or to the  appointment of or taking  possession of
its  property  by any  official  in an  involuntary  case  or  other  proceeding
commenced  against it or (vii) take any action for the purpose of effecting  any
of the foregoing;

                  (d)   Involuntary   Bankruptcy  or   Insolvency   Proceedings.
Proceedings for the appointment of a receiver,  trustee, liquidator or custodian
of the Company or of all or a substantial  part of the property  thereof,  or an
involuntary case or other  proceedings  seeking  liquidation,  reorganization or
other  relief  with  respect  to the  Company  or the  debts  thereof  under any
bankruptcy,  insolvency or other similar law now or hereafter in effect shall be
commenced and an order for relief entered,  or such case or proceeding shall not
be dismissed or discharged within 45 days of commencement; or

                  (e) Event of Default on Senior  Debt. A default in the payment
of principal premium, if any, or interest with respect to Senior Debt.

                                       17

<PAGE>



         3.  Rights  of Holder  Upon  Exchange  Event.  Upon the  occurrence  or
existence of any Exchange Event,  the Note shall  automatically be exchanged for
the XM Owned  Shares and XM Note Shares,  and all rights,  title and interest in
the Collateral shall be transferred to Holder.

         4.  Subordination.  The  indebtedness  evidenced by this Note is hereby
expressly  subordinated,  to the extent and in the manner hereinafter set forth,
in right of payment to the prior payment in full of all of the Company's  Senior
Debt.

                  (a)  Event of  Default  on Senior  Debt.  No  payments  by the
Company on account of  principal  or  interest on this Note shall be made unless
full payment of amounts then due for principal, premium, if any, and interest on
Senior Debt has been made or duly  provided  for in money or money's  worth.  No
payment by the Company on account of principal or interest on this Note shall be
made if, at the time of such payment or immediately after giving effect thereto,
(i) there shall exist a default in the payment of principal, premium, if any, or
interest  with respect to any Senior Debt,  or (ii) there shall have occurred an
event of default (other than a default in the payment of principal,  premium, if
any, or interest) with respect to any Senior Debt, as defined  therein or in the
instrument under which the same is outstanding,  permitting the holders thereof,
or any trustee under any such  instrument,  to accelerate the maturity  thereof,
and such event of default  shall not have been cured or waived or shall not have
ceased to exist.  Nothing in this  Section  4(a) shall be deemed to restrict the
Holder's exchange rights set forth in Section 2(e).

                  (b)   Insolvency   Proceedings.   If  there  shall  occur  any
receivership,  insolvency,  assignment for the benefit of creditors, bankruptcy,
reorganization,  or  arrangements  with  creditors  (whether or not  pursuant to
bankruptcy or other insolvency  laws),  sale of all or substantially  all of the
assets,  dissolution,  liquidation,  or any other  marshaling  of the assets and
liabilities of the Company, no amount shall be paid by the Company in respect of
the principal of,  interest on or other amounts due with respect to this Note at
the time  outstanding,  unless and until the  principal  of  (premium,  if any),
interest  on,  and any fees and  expenses  relating  to,  the  Senior  Debt then
outstanding shall be paid in full.

                  (c) Subrogation.  Subject to the payment in full of all Senior
Debt, the Holder of this Note shall be subrogated to the rights of the holder(s)
of such Senior Debt (to the extent of the payments or distributions  made to the
holder(s) of such Senior Debt)  pursuant to the  provisions of this Section 4 to
receive payments and  distributions  of assets of the Company  applicable to the
Senior Debt until the principal of and interest on this Note is paid in full and
no such  payments  or  distributions  to the  Holder of  assets  of the  Company
otherwise  distributable  to the holders of Senior  Debt  shall,  as between the
Company, its creditors other than the holders of Senior Debt, and the Holder, be
deemed to be a payment  by the  Company  to the  Holder of or on  account of the
Note.  It is  understood  that the  provisions  of this Section 4(c) are and are
intended  solely for the purpose of defining the relative  rights of the Holder,
on the one hand, and the holders of Senior Debt, on the other hand.

                  (d) No Impairment.  Nothing  contained in this Section 4 shall
impair,  as between the Company and the Holder,  the  obligation of the Company,
subject to the terms and conditions  hereof,  to pay to the Holder the principal
hereof and interest hereon as and when the same become due and payable, or shall
prevent the Holder of this Note,  upon default  hereunder,  from  exercising all
rights, powers and remedies otherwise provided herein or by applicable law.

                  (e)  Reliance of Holders of Senior  Debt.  The Holder,  by its
acceptance  hereof,  shall be deemed to acknowledge and agree that the foregoing
subordination  provisions  are, and are intended to be, an  inducement  to and a
consideration  of each  holder of Senior  Debt,  whether  such  Senior  Debt was
created or acquired before or after the creation of the  indebtedness  evidenced
by this Note,  and each such holder of Senior Debt shall be deemed  conclusively
to have relied on such subordination  provisions in acquiring and holding, or in
continuing to hold, such Senior Debt.

                                       18

<PAGE>



         5.       Collateral.

                  (a) To secure the  Company's  payment and  performance  of the
Obligations and to secure the Company's  prompt,  full and faithful  performance
and  observance of all of the  provisions  under this Note and the Note Purchase
Agreement,  the Company (i) hereby grants the Holder a security  interest in all
of the Company's right, title and interest in and to the XM Owned Shares and the
XM Convertible Note including any right to XM Note Shares exchangeable  therefor
(collectively,   the  "Collateral"),  and  (ii)  delivers  herewith,  the  stock
certificates  representing  the XM Owned  Shares with stock  powers  executed in
blank and the XM Convertible Note.

                  (b) The Company covenants and agrees with Holder that: (a) the
security  interest  granted under this Note is in addition to any other security
interest  from time to time held by the Holder;  (b) the Holder may realize upon
all or part of any Collateral in any order it desires and any realization by any
means upon any Collateral  will not bar realization  upon any other  Collateral;
and (c) the security interest created is a continuing security interest and will
cover and secure  all  Obligations  both  present  and future of the  Company to
Holder pursuant to this Note. The Company  further  covenants and agrees to take
all  actions  requested  by the  Holder to  establish  or perfect  the  security
interest granted under this Note.

         6.  Prepayment.  This Note may be  prepaid as a whole or in part at any
time prior to the Maturity  Date upon at least ten Business  Days prior  written
notice to the Holder.  Any such prepayment shall be applied first to the payment
of expenses  due under this Note,  second to  interest  accrued on this Note and
third,  if the amount of prepayment  exceeds the amount of all such expenses and
accrued interest, to the payment of principal of this Note.

         7.       Exchange.

                  (a) Exchange for XM Common Stock.  The Holder,  at its option,
may, on two Business Days prior written notice (each an "Exchange  Notice"),  on
one or more  occasions  any time  after the  earlier  of an  Exchange  Event and
January 15, 2000,  and on or prior to repayment in full of  principal,  interest
and any  other  amounts  due and  owing  hereunder  (each an  "Exchange  Date"),
exchange  all of the  principal  then  outstanding  on this  Note,  or a portion
thereof in an amount not less than  $250,000 (and if greater than  $250,000,  in
increments of $1,000 above such amount),  for (i) XM Owned Shares,  (ii) XM Note
Shares issued to the Company on or prior to such Exchange  Date, or (iii) rights
to XM Note Shares  issuable  to the  Company,  at an  exchange  rate of $875,000
principal  amount  for each one (1) share of XM Owned  Shares or XM Note  Shares
issued  or  issuable  to the  Company  (the  "Exchange  Price").  Any  principal
exchanged  under this  Section  7(a) shall be  exchanged  first for,  and to the
extent of, XM Owned Shares,  second for XM Note Shares issued to the Company, if
any,  and then for the XM Note.  Upon full  exchange  of this Note,  the Company
shall be forever  released from all its obligations  and liabilities  under this
Note. If, on the Maturity  Date, the Company has not received a timely  Exchange
Notice for the then  outstanding  principal  amount under this Note, the Company
may, at its option, (x) require the Holder to exchange such remaining  principal
for XM Owned  Shares  and/or XM Note  Shares  pursuant to the terms set forth in
this Section 7 in full satisfaction of all Obligations  hereunder,  or (y) repay
all remaining  principal and accrued  interest due as of the Maturity Date. Upon
such exchange or repayment pursuant to the immediately  preceding sentence,  the
Company shall be forever released from all its obligations and liabilities under
this Note.

                   (b) Mechanics and Effect of Exchange. This Section 7(b) shall
apply to any  partial  exchange of this Note other than in  connection  with the
exercise  by the  Company of its option  under  Section  7(a)(x)  above.  On any
exchange  covered by this Section 7(b), the Company shall transfer to the Holder
(i) the XM Owned  Shares,  XM Note  Shares  or XM  Convertible  Note for which a
portion of this Note is exchanged and (ii) a replacement  promissory note having
identical  terms to this Note,  except that the principal  amount  thereof shall
equal the difference  between (x) the principal  amount of this Note immediately
prior to such exchange minus (y) the portion of such

                                       19

<PAGE>



principal amount exchanged for XM Owned Shares, XM Note Shares or XM Convertible
Note. Upon exchange of this Note pursuant to this Section 7(b), the Holder shall
surrender this Note, duly endorsed,  at the principal office of the Company.  At
its expense,  the Company shall, as soon as practicable  thereafter,  deliver to
such Holder at such  principal  office a  certificate  or  certificates  for the
number of XM Owned  Shares or XM Note  Shares  held by the  Company to which the
Holder shall be entitled upon such exchange,  together with any other securities
and property to which the Holder is entitled upon such exchange  under the terms
of this Note. The Holder's right to all accrued interest relating to the portion
of the  principal  amount  exchanged  pursuant  to this  Section  7(b)  shall be
extinguished upon such exchange.

                  (c) Interest on XM Convertible Note. Interest, if any, paid in
cash by XM under the XM  Convertible  Note  shall be  allocated  and paid to the
Company to the extent such interest accrued before any Exchange Date relating to
the XM Convertible  Note, and to the Holder to the extent such interest  accrued
after any such Exchange Date.

         8.  Successors  and Assigns.  Subject to the  restrictions  on transfer
described  in  Sections  10 and 11 hereof,  the rights  and  obligations  of the
Company  and the  Holder of this Note  shall be  binding  upon and  benefit  the
successors, assigns, heirs, administrators and transferees of the parties.

         9.  Waiver and  Amendment.  The waiver or failure of the Company or the
Holder  to  exercise  in any  respect  any  right  provided  in  this  Note on a
particular  occasion  shall not be  deemed a waiver  of such  right on any other
occasion or a waiver of any other right.  To be  effective,  a waiver must be in
writing  and be signed by the party that is entitled to the benefit of the right
that is being waived. No amendment or modification of this Note shall be made or
deemed  effective  unless in writing and  executed  and  delivered  by the party
against whom enforcement of such amendment or modification is sought.

         10.  Transfer of this Note or Securities  Issuable on Exchange  Hereof.
This Note may not be  transferred  in  violation of the  restrictive  legend set
forth at the head hereof.  Each new Note issued upon transfer of this Note shall
bear a legend as to the applicable  restrictions on  transferability in order to
ensure  compliance with the Securities Act, unless in the opinion of counsel for
the Company such legend is not required in order to ensure  compliance  with the
Securities Act. The Company may issue stop transfer instructions to its transfer
agent in connection with such restrictions.  Subject to the foregoing, transfers
of this Note shall be registered  upon  registration  books  maintained for such
purpose by or on behalf of the Company.  Prior to  presentation of this Note for
registration of transfer,  the Company shall treat the registered  holder hereof
as the owner and holder of this Note for the purpose of  receiving  all payments
of principal and interest hereon and for all other purposes whatsoever,  whether
or not this Note shall be  overdue,  and the  Company  shall not be  affected by
notice to the contrary.

         11. Assignment by the Company. Neither this Note nor any of the rights,
interests  or  obligations  hereunder  may be  assigned,  by operation of law or
otherwise,  in whole or in part,  by the  Company,  without  the  prior  written
consent of the Holder.

         12.  Treatment of Note. To the extent  permitted by generally  accepted
accounting  principles,  the Company will treat,  account and report the Note as
debt and not equity for  accounting  purposes  and with  respect to any  returns
filed with federal, state or local tax authorities.

         13. Notices.  Any notice,  request or other  communication  required or
permitted  hereunder  shall be in writing  and shall be deemed to have been duly
given if personally delivered or mailed by registered or certified mail, postage
prepaid,  or by recognized  overnight  courier,  personal  delivery or facsimile
transmission at the respective  addresses or facsimile  number of the parties as
set forth below:

                                       20

<PAGE>



                  If to the Company:

                  American Mobile Satellite Corporation
                  10802 Parkridge Blvd.
                  Reston, Virginia 20191-5416
                  Attention:  Randy Segal, Esq.
                  Fax No.:   (703) 758-6134

                  If to Holder:

                  The Baron Asset Fund Series
                  c/o Baron Asset Fund
                  767 Fifth Avenue, 49th Floor
                  New York, New York 10153
                  Attention:  Linda Martinson, Esq.
                  Fax No.:   (212) 583-2014

         Any party hereto may by notice so given change its address or facsimile
number for future notice hereunder.  Notice shall conclusively be deemed to have
been given when received.

         14.  Expenses;  Waivers.  If action is instituted to collect this Note,
the  Company  promises  to  pay  all  costs  and  expenses,  including,  without
limitation,  reasonable  attorneys' fees and costs,  incurred in connection with
such action. The Company hereby waives notice of default,  presentment or demand
for payment,  protest or notice of  nonpayment or dishonor and all other notices
or demands relative to this instrument.

         15.  Governing  Law.  This Note and all  actions  arising  out of or in
connection  with this Note shall be governed by and construed in accordance with
the laws of the State of New York, without regard to conflict of laws provisions
of the State of New York or of any  other  state.  In the  event of any  dispute
among or between  any of the  parties to this Note  arising  out of the terms of
this Note,  the parties  hereby  consent to the  exclusive  jurisdiction  of the
federal and state courts located in the State of New York for resolution of such
dispute,  and  agree  not to  contest  such  exclusive  jurisdiction  or seek to
transfer any action relating to such dispute to any other jurisdiction.


                                       21

<PAGE>



         IN WITNESS WHEREOF, the Company has caused this Note to be issued as of
the date first written above.

                                                AMERICAN MOBILE SATELLITE
                                                CORPORATION


                                                By:      /s/Randy S. Segal
                                                         -----------------

                                                Name:    Randy S. Segal

                                                Title:   Vice President



                                       22






                                                                      EXHIBIT 3a



      AMENDMENT NO. 1 TO JUNIOR SUBORDINATED SECURED EXCHANGEABLE NOTE AND
                                     CONSENT



         This Amendment No. 1 to Junior Subordinated  Secured  Exchangeable Note
and Consent (this "Amendment") is entered into as of the 7th day of July between
American Mobile Satellite  Corporation,  a Delaware corporation (the "Company"),
and Baron Asset Fund (the "Holder"), on behalf of The Baron Asset Fund Series, a
business trust organized under the laws of the Commonwealth of Massachusetts.





                                    RECITALS



         WHEREAS,  the Company issued a Junior Subordinated Secured Exchangeable
Note (the "Note") dated January 15, 1999 in the principal  amount of $21,500,000
in favor of the Holder;

         WHEREAS, the Company and the Holder mutually desire to amend the  terms
of the Note as set forth in this Amendment;

         NOW, THEREFORE,  in consideration of the premises and the covenants set
forth herein, the parties agree as follows:

         1. Definitions. Capitalized terms used herein and not otherwise defined
herein shall have the meanings assigned to such terms in the Note.

         2. Maturity.  The words "on September 30, 2006"  appearing in the first
paragraph  of the Note shall be deleted  and the  following  phrase  substituted
therefor:

                           "(a)  on  December  31,  2004,  or (b) by  reason  of
                  automatic  extension  without  any action by any party,  if XM
                  Satellite  Radio  Holdings  Inc. ("XM  Holdings")  issues High
                  Yield  Debt  (as  defined  in  the  Exchange,   Amendment  and
                  Recapitalization Agreement dated as of July 7, 1999 between XM
                  Holdings and the Company (the  "Recapitalization  Agreement"))
                  prior to June 30, 2001, on the first  Business Day (as defined
                  in the Recapitalization  Agreement) following the date that is
                  six (6) months from the maturity  date of such High Yield Debt
                  or,  following such first issuance,  any other High Yield Debt
                  issued prior to June 30,  2002,  unless this Note is otherwise
                  exchanged in accordance with the terms hereof."

         3.  XM Common Stock.

                  (a) All  references  to "XM Common Stock" in the Note shall be
deleted and the words "XM Class B Common Stock" shall be  substituted  therefor.
Furthermore,  the  definition  of "XM Common  Stock" in Section 1(f) of the Note
shall  be  deleted  in its  entirety  and the  following  shall  be  substituted
therefor:

                           "'XM Class B Common  Stock'  means the Class B common
                  stock of XM  Holdings,  having a par value of $0.01 per share,
                  or, in the event that the Company shall, at

                                       23

<PAGE>



                  the relevant time,  have converted the XM Class B Common Stock
                  held by it to XM Class A Common Stock,  all  references to 'XM
                  Class B Common  Stock'  shall be  deemed  to mean the  Class A
                  Common Stock."

                  (b) A new  definition  of "XM Class A Common  Stock"  shall be
added to Section 1 of the Note as follows:

                      "'XM Class A Common  Stock' means the Class A common stock
                  of XM Holdings, having a par value of $0.01 per share."

         4.  Consent.  Pursuant to Section 2(l) of the Note  Purchase  Agreement
dated as of January  15, 1999  between  the  Company and the Holder,  the Holder
hereby  consents to the  amendments  to the XM  Convertible  Note  contained  in
Section 2.2 of the Exchange,  Amendment and Recapitalization  Agreement dated as
of July 7, 1999 between XM Holdings and the Company.

         5. Miscellaneous:  Except as specifically amended hereby, all terms and
provisions of the Note shall remain in full force and effect. This Amendment may
be  executed  in one or more  counterparts,  each of which  shall be  deemed  an
original,  and all of which, when taken together,  shall be deemed to constitute
one and the same instrument.



                                       24

<PAGE>




         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly  executed  and  delivered by their  proper and duly  authorized  directors,
officers or representatives as of the day and year first above written.



                                              AMERICAN MOBILE SATELLITE
                                              CORPORATION


                                              By: /s/Randy Segal
                                                  --------------
                                                  Name:   Randy Segal
                                                  Title:  Senior Vice President




                                              BARON ASSET FUND, on behalf of
                                              THE BARON ASSET FUND SERIES


                                              By: /s/Ronald Baron
                                                  ---------------
                                                  Name:   Ronald Baron
                                                  Title:  Chairman & CEO


                                       25

<PAGE>




© 2022 IncJournal is not affiliated with or endorsed by the U.S. Securities and Exchange Commission