REGISTRATION RIGHTS AGREEMENT

         REGISTRATION RIGHTS AGREEMENT (this "Agreement"),  dated as of December
7,  2000,  by and  among  Teligent,  Inc.,  a  Delaware  corporation,  with  its
headquarters  located at 8065 Leesburg Pike, Suite 400,  Vienna,  Virginia 22182
(the "Company"),  and the undersigned  (together with its respective  affiliates
and any  assignee or  transferee  of all of its rights  hereunder,  the "Initial
Investor").

         WHEREAS:

         A. In connection with the Common Stock Purchase  Agreement by and among
the parties hereto of even date herewith (the "Purchase Agreement"), the Company
has agreed,  upon the terms and subject to the conditions  contained therein, to
issue  and  sell  to  the  Initial  Investor,  from  time  to  time,  (i)  up to
$250,000,000  of its Class A Common Stock,  par value $0.01 per share (the "Draw
Down  Shares") and (ii)  warrants  (the  "Warrants")  to acquire up to 4,972,370
shares of Class A Common Stock,  par value $0.01 per share (the "Common Stock"),
upon the terms and conditions and subject to the  limitations and conditions set
forth in the Warrants dated December 7, 2000; and

         B. To induce the Initial  Investor to execute and deliver the  Purchase
Agreement,  the Company has agreed to provide certain  registration rights under
the  Securities  Act  of  1933,  as  amended,  and  the  rules  and  regulations
thereunder,  or any similar  successor  statute  (collectively,  the "Securities
Act"), and applicable state securities laws;

         NOW,  THEREFORE,  in  consideration  of the  premises  and  the  mutual
covenants  contained  herein  and other  good and  valuable  consideration,  the
receipt and  sufficiency of which are hereby  acknowledged,  the Company and the
Initial Investor hereby agree as follows:

         1.       DEFINITIONS.

                  a. As used in this  Agreement,  the following terms shall have
         the following meanings:

                            (i) "Investors"  means the Initial  Investor and any
         transferee or assignee who agrees to become bound by the  provisions of
         this Agreement in accordance with Section 9 hereof.

                           (ii)  "register,"  "registered,"  and  "registration"
         refer to a registration effected by preparing and filing a Registration
         Statement or  Statements  in  compliance  with the  Securities  Act and
         pursuant to Rule 415 under the  Securities  Act or any  successor  rule
         providing for offering  securities on a continuous  basis ("Rule 415"),
         and the declaration or ordering of effectiveness  of such  Registration
         Statement by the United States Securities and Exchange  Commission (the
         "SEC").

                          (iii)  "Registrable  Securities"  shall  mean the Draw
         Down Shares, the Warrant Shares (as defined in the Purchase  Agreement)
         and any other shares of capital  stock issued or issuable as a dividend
         on or in exchange for or otherwise with respect to the Draw Down Shares
         and the Warrant  Shares until (i) the  Registration  Statement has been
         declared effective by the SEC and all such shares have been disposed of
         pursuant to the Registration Statement,  (ii) all such shares have been
         sold under circumstances  under which all of the applicable  conditions
         of Rule  144  promulgated  under  the  Securities  Act (or any  similar
         provision  then in force)  ("Rule 144") are met,  (iii) all such shares
         have been  otherwise  transferred  to holders who may trade such shares
         without  restriction  under the  Securities  Act,  and the  Company has
         delivered a new  certificate  or other  evidence of ownership  for such
         securities not bearing a restrictive  legend, (iv) such time as, in the
         opinion of counsel to the Investor, all such shares may be sold without
         any time, volume or manner limitations  pursuant to Rule 144(k) (or any
         similar  provision  then in effect) under the Securities Act or (v) any
         combination of the foregoing relating to all such shares.

                           (iv)   "Registration   Statement(s)"   shall  mean  a
         registration  statement  on  Form  S-3  (if  use of  such  form is then
         available to the Company  pursuant to the rules of the SEC and, if not,
         on such other form  promulgated  by the SEC for which the Company  then
         qualifies and which counsel for the Company shall deem  appropriate and
         which  form  shall  be  available  for the  resale  of the  Registrable
         Securities  to  be  registered   thereunder  in  accordance   with  the
         provisions  of  this  Agreement  and  the  Purchase  Agreement,  and in
         accordance   with  the  intended   method  of   distribution   of  such
         securities),  for the registration of the resale by the Investor of the
         Registrable Securities under the Securities Act.

                  b.  Capitalized  terms used herein and not  otherwise  defined
         herein  shall have the  respective  meanings  set forth in the Purchase
         Agreement.

         2.       REGISTRATION.

                  a. Mandatory Registration.  The Company shall prepare, and, on
or prior to the date (the "Filing Date") which is forty-five (45) days after the
Closing  Date  (as  defined  in the  Purchase  Agreement),  file  with the SEC a
Registration Statement covering the resale of the Registrable Securities,  which
Registration Statement, to the extent allowable under the Securities Act and the
rules and regulations  promulgated  thereunder (including Rule 416), shall state
that such  Registration  Statement  also  covers  such  indeterminate  number of
additional shares of Common Stock as may become issuable (i) with respect to the
Draw Down  Shares and  Warrant  Shares and (ii) upon  exercise  of or  otherwise
pursuant to the Warrants to prevent dilution resulting from stock splits,  stock
dividends  or  similar  transactions.  The  number of  shares  of  Common  Stock
initially included in such Registration  Statement shall be no less than the sum
of (x) the  aggregate  number  of Draw  Down  Shares  issuable  pursuant  to the
Purchase  Agreement  (assuming that  $250,000,000 of Draw Down Shares were to be
issued at a price equal to the VWAP (as defined in the  Purchase  Agreement)  on
the Closing  Date) and (y) one hundred  twenty  percent  (120%) of the aggregate
number of Warrant  Shares that are  issuable  upon the  exercise of or otherwise
pursuant to the  Warrants,  without  regard to any  limitation  on the Company's
ability to effect Draw Downs under the Purchase  Agreement or on the  Investor's
ability to exercise the Warrants.  The Company  acknowledges  that the number of
shares initially included in the Registration  Statement represents a good faith
estimate of the maximum number of shares  issuable under the Purchase  Agreement
and upon  exercise of or otherwise  pursuant to the Warrants.  The  Registration
Statement  (and each  amendment  or  supplement  thereto,  and each  request for
acceleration of  effectiveness  thereof) shall be provided to and subject to the
approval of the Initial  Investor  and its counsel  prior to its filing or other
submission.  The Company shall provide the Initial Investor and its counsel with
a copy of the Registration  Statement and any pre- or  post-effective  amendment
thereto not less than seven (7) business days prior to the intended  filing date
and shall provide copies of any  supplements not less than two (2) business days
prior to the intended filing date.

                  b.  Underwritten  Offering.  If  any  offering  pursuant  to a
Registration  Statement pursuant to Section 2(a) hereof involves an underwritten
offering,  the  Investors  who hold a majority in  interest  of the  Registrable
Securities  subject  to  such  underwritten  offering,  with  the  consent  of a
majority-in-interest of the Initial Investor, shall have the right to select one
legal  counsel  and an  investment  banker or bankers and manager or managers to
administer  the  offering,  which  investment  banker or  bankers  or manager or
managers shall be reasonably  satisfactory to the Company. In the event that any
Investors  elect  not  to  participate  in  such  underwritten   offering,   the
Registration  Statement covering all of the Registrable Securities shall contain
appropriate  plans of  distribution  reasonably  satisfactory  to the  Investors
participating in such  underwritten  offering and the Investors  electing not to
participate in such underwritten  offering (including,  without limitation,  the
ability  of  non-participating  Investors  to sell from time to time at any time
during the effectiveness of such Registration Statement).

                  c.  Payments by the  Company.  The Company  shall use its best
efforts  to  obtain  effectiveness  of the  Registration  Statement  as  soon as
practicable. If (i) after the Registration Statement(s) covering the Registrable
Securities  required to be filed by the Company  pursuant to Section 2(a) hereof
is declared  effective by the SEC,  sales of all of the  Registrable  Securities
cannot be made pursuant to the Registration  Statement, or (ii) the Common Stock
is  not  listed  or  included  for  quotation  on  the  Nasdaq  National  Market
("Nasdaq"),  the Nasdaq SmallCap Market ("Nasdaq SmallCap"),  the New York Stock
Exchange (the "NYSE") or the American Stock Exchange (the "AMEX") after being so
listed or included for  quotation,  then the Company  will make  payments to the
Investors in such amounts and at such times as shall be  determined  pursuant to
this Section 2(c) as partial  relief for the damages to the  Investors by reason
of any such  delay in or  reduction  of their  ability  to sell the  Registrable
Securities (which remedy shall not be exclusive of any other remedies  available
at law or in equity).  The Company  shall pay to the  Investors  in  immediately
available funds an amount equal to one percent (1%) of the aggregate  Investment
Amount  represented  by Draw Down Shares  previously  purchased  by the Investor
pursuant  to the  Purchase  Agreement  for each thirty day period (pro rated for
partial  periods)  during the  Registration  Period (as defined  below) (i) that
sales  of all of the  Registrable  Securities  cannot  be made  pursuant  to the
Registration  Statement  after  the  Registration  Statement  has been  declared
effective (including, without limitation, when sales cannot be made by reason of
the Company's  failure to properly  supplement or amend the prospectus  included
therein in accordance with the terms of this Agreement  (including  Section 3(b)
hereof or otherwise), but excluding any days during an Allowed Delay (as defined
in Section  3(h));  and (ii) that the Common Stock is not listed or included for
quotation on the Nasdaq,  Nasdaq SmallCap,  NYSE or AMEX or that trading thereon
is halted  (clauses (i) and (ii) are each referred to herein as an  "Ineffective
Period").  Such payments  pursuant  hereto shall be made within five (5) Trading
Days after the earliest to occur of (i) the expiration of the Commitment Period,
(ii) the expiration of an Ineffective  Period (or if an Ineffective Period shall
last more than thirty (30)  calendar  days,  the  expiration of each thirty (30)
calendar days of an Ineffective Period).

                  d.  Eligibility  for Form  S-3.  The  Company  represents  and
warrants that it meets the registrant  eligibility and transaction  requirements
for the use of Form S-3 for registration of the sale by the Initial Investor and
any other Investors of the Registrable Securities and the Company shall file all
reports  required to be filed by the Company with the SEC in a timely  manner so
as to maintain such eligibility for the use of Form S-3.

         3.       OBLIGATIONS OF THE COMPANY.

         In connection with the registration of the Registrable Securities,  the
Company shall have the following obligations:

                  a. The Company shall prepare  promptly,  and file with the SEC
as soon as  practicable  after the Closing  Date (but in no event later than the
Filing Date), a Registration Statement with respect to the number of Registrable
Securities  provided in Section  2(a),  and  thereafter  use its best efforts to
cause such Registration  Statement relating to Registrable  Securities to become
effective  as soon as  possible  after such  filing,  and keep the  Registration
Statement  effective  pursuant  to Rule 415 at all times until such date as such
shares  are  no  longer  considered   Registrable  Securities  pursuant  to  the
definition of such term set forth in Section  1(a)(ii) hereof (such period being
referred  to  as  the  "Registration  Period"),   which  Registration  Statement
(including  any  amendments or supplements  thereto and  prospectuses  contained
therein)  shall not contain any untrue  statement of a material  fact or omit to
state a material  fact required to be stated  therein,  or necessary to make the
statements therein not misleading.

                  b.  The  Company  shall  prepare  and  file  with the SEC such
amendments  (including   post-effective   amendments)  and  supplements  to  the
Registration   Statements  and  the  prospectus  used  in  connection  with  the
Registration  Statements as may be necessary to keep the Registration Statements
effective at all times during the Registration  Period, and, during such period,
comply with the provisions of the Securities Act with respect to the disposition
of  all  Registrable  Securities  of the  Company  covered  by the  Registration
Statements  until  such  time as all of such  Registrable  Securities  have been
disposed of in accordance with the intended methods of disposition by the seller
or sellers  thereof as set forth in the  Registration  Statements.  In the event
that on any  Trading Day (as defined in the  Purchase  Agreement)  the number of
shares available under a Registration Statement filed pursuant to this Agreement
is insufficient to cover all of the  Registrable  Securities  issued or issuable
under the Purchase  Agreement and upon exercise of or otherwise  pursuant to the
Warrants,  without giving effect to any limitations on the Company's  ability to
effect Draw Downs under the Purchase  Agreement or on the Investors'  ability to
exercise the Warrants (the "Registration Trigger Date"), the Company shall amend
the Registration  Statement,  or file a new Registration Statement (on the short
form available  therefore,  if  applicable),  or both, so as to cover all of the
Registrable  Securities  so issued or  issuable  (without  giving  effect to any
limitations on Draw Downs under the Purchase  Agreement or on exercise contained
in the Warrants,  as  applicable) as of the  Registration  Trigger Date, in each
case, as soon as practicable,  but in any event within twenty (20) business days
after the  necessity  therefor  arises  (based on the market price of the Common
Stock and other  relevant  factors  on which the  Company  reasonably  elects to
rely). The Company shall use its best efforts to cause such amendment and/or new
Registration  Statement to become effective as soon as practicable following the
filing  thereof,  but in any event within  ninety (90) days of the  Registration
Trigger Date.  The  provisions  of Section 2(c) above shall be  applicable  with
respect to the Company's obligations under this Section 3(b).

                  c. On or  before  each  Draw  Down  Date  (as  defined  in the
Purchase  Agreement),  the  Company  shall  prepare  and  file  with  the  SEC a
supplement to the Registration  Statement,  in form and substance agreed upon by
the  parties,  regarding  the Draw  Down  including  the  Draw  Down  Date,  the
Investment  Amount, the number of shares sold to the Investor in connection with
all  previous  Draw Downs,  if not  previously  disclosed in an SEC Document (as
defined in the Purchase Agreement),  and any additional  information required by
SEC rules and regulations, including Item 507 of Regulation S-K.

                  d.  The  Company  shall   furnish  to  each   Investor   whose
Registrable  Securities are included in a  Registration  Statement and its legal
counsel (i) promptly after the same is prepared and publicly distributed,  filed
with  the  SEC,  or  received  by the  Company,  one  copy of each  Registration
Statement and any amendment thereto, each preliminary  prospectus and prospectus
and each amendment or supplement  thereto,  and, in the case of the Registration
Statement  referred to in Section 2(a),  each letter  written by or on behalf of
the Company to the SEC or the staff of the SEC, and each item of  correspondence
from the SEC or the staff of the SEC, in each case relating to such Registration
Statement (other than any portion of any thereof which contains  information for
which the Company has sought  confidential  treatment),  and (ii) such number of
copies of a prospectus,  including a preliminary prospectus,  and all amendments
and supplements thereto and such other documents as such Investor may reasonably
request in order to facilitate  the  disposition of the  Registrable  Securities
owned by such  Investor.  The Company will  immediately  notify each Investor by
facsimile  of  the   effectiveness  of  each   Registration   Statement  or  any
post-effective  amendment.  The  Company  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.

                  e. The Company  shall use  reasonable  efforts to (i) register
and qualify the Registrable  Securities  covered by the Registration  Statements
under such other  securities  or "blue  sky" laws of such  jurisdictions  in the
United  States  as  the  Investors  who  hold  a  majority  in  interest  of the
Registrable  Securities being offered reasonably request,  (ii) prepare and file
in those jurisdictions such amendments (including post-effective amendments) and
supplements  to such  registrations  and  qualifications  as may be necessary to
maintain the effectiveness  thereof during the Registration  Period,  (iii) take
such other  actions as may be  necessary  to  maintain  such  registrations  and
qualifications in effect at all times during the Registration  Period,  and (iv)
take all  other  actions  reasonably  necessary  or  advisable  to  qualify  the
Registrable Securities for sale in such jurisdictions;  provided,  however, that
the  Company  shall not be required in  connection  therewith  or as a condition
thereto to (a)  qualify to do business  in any  jurisdiction  where it would not
otherwise be required to qualify but for this Section 3(e),  (b) subject  itself
to general  taxation  in any such  jurisdiction,  (c) file a general  consent to
service of process in any such  jurisdiction,  (d) provide any undertakings that
cause the Company undue expense or burden, or (e) make any change in its charter
or bylaws,  which in each case the Board of Directors of the Company  determines
to be contrary to the best interests of the Company and its stockholders.

                  f. In the event Investors who hold a  majority-in-interest  of
the Registrable  Securities  being offered in the offering (with the approval of
the Initial  Investor) select  underwriters for the offering,  the Company shall
enter into and perform its obligations under an underwriting agreement, in usual
and customary form, including, without limitation, customary indemnification and
contribution obligations, with the underwriters of such offering.

                  g. The Company will immediately  notify each Investor upon the
occurrence  of  any of the  following  events  in  respect  of the  Registration
Statement  or related  prospectus  in  respect of the resale of the  Registrable
Securities:  (i) receipt of any request for additional  information from the SEC
or any other  federal  or state  governmental  authority  during  the  period of
effectiveness of the Registration Statement, the response to which would require
any  amendments  or  supplements  to  the  Registration   Statement  or  related
prospectus;  (ii)  the  issuance  by the  SEC  or any  other  federal  or  state
governmental  authority of any stop order  suspending the  effectiveness  of the
Registration  Statement or the initiation of any  proceedings  for that purpose;
(iii)  receipt  of  any  notification  with  respect  to the  suspension  of the
qualification or exemption from  qualification of any of the Securities for sale
in any  jurisdiction or the initiation or threatening of any proceeding for such
purpose;  and (iv) the happening of any event that makes any  statement  made in
the Registration Statement or related prospectus or any document incorporated or
deemed to be incorporated therein by reference untrue in any material respect or
that requires the making of any changes in the Registration  Statement,  related
prospectus or documents so that, in the case of the Registration  Statement,  it
will not contain any untrue  statement  of a material  fact or omit to state any
material fact required to be stated  therein or necessary to make the statements
therein not misleading,  and that in the case of the related prospectus, it will
not  contain  any  untrue  statement  of a  material  fact or omit to state  any
material fact required to be stated  therein or necessary to make the statements
therein,  in the light of the  circumstances  under  which they were  made,  not
misleading; provided, however that prior to the disclosure by the Company of any
material   non-public   information  to  the  Investors  or  their  advisors  or
representatives  pursuant to this Section 3(g) or any other  provisions  of this
Agreement,  the  Company  shall  identify  such  information  as being  material
non-public  information  and shall provide the Investors with the opportunity to
accept or refuse to accept such material non-public information.

                  h. As promptly as practicable after becoming aware of an event
specified in Section 3(g)(iv) of this Agreement,  the Company shall use its best
efforts  promptly  to prepare a  supplement  or  amendment  to any  Registration
Statement to correct such untrue statement or omission,  and deliver such number
of copies of such  supplement or amendment to each Investor as such Investor may
reasonably  request;  provided that,  for not more than twenty (20)  consecutive
Trading  Days (or a total of not more than sixty (60) Trading Days in any twelve
(12) month period),  the Company may delay the disclosure of material non-public
information  concerning  the  Company  (as well as  prospectus  or  Registration
Statement  updating)  the  disclosure  of which at the time is not,  in the good
faith opinion of the Company,  in the best interests of the Company (an "Allowed
Delay");  provided,  further,  that the Company  shall  promptly  (i) notify the
Investors  in writing of the  existence  of (but in no event,  without the prior
written consent of an Investor,  shall the Company disclose to such Investor any
of the facts or circumstances  regarding) material non-public information giving
rise to an Allowed  Delay and (ii) advise the  Investors in writing to cease all
sales under such Registration Statement until the end of the Allowed Delay. Upon
expiration  of the Allowed  Delay,  the Company  shall again be bound by Section
3(g) and the first sentence of this Section 3(h) with respect to the information
giving  rise  thereto.  In the event  that the  Investors  consent to receipt of
material non-public  information pursuant to the second proviso contained in the
first  sentence of this Section 3(h),  the  Investors  hereby agree to keep such
information confidential until the earlier of (i) the date when such information
is publicly  disclosed by the Company and (ii) the date which is twenty-one (21)
Trading Days after the beginning of the period constituting such Allowed Delay.

                  i. The  Company  shall use its best  efforts  to  prevent  the
issuance  of  any  stop  order  or  other  suspension  of  effectiveness  of any
Registration  Statement,  and,  if  such an  order  is  issued,  to  obtain  the
withdrawal  of such order at the  earliest  possible  moment and to notify  each
Investor  who holds  Registrable  Securities  being sold (or, in the event of an
underwritten  offering, the managing underwriters) of the issuance of such order
and the resolution thereof.

                  j.  The  Company   shall  permit  a  single  firm  of  counsel
designated by the Initial Investor to review such Registration Statement and all
amendments and supplements  thereto (as well as all requests for acceleration or
effectiveness  thereof  and any  correspondence  between the Company and the SEC
relating  to the  Registration  Statement)  a  reasonable  period  of  time  (as
specified  in Section  2(c) above)  prior to their  filing with the SEC, and not
file any document (nor send any  correspondence) in a form to which such counsel
reasonably  objects  and  will not  request  acceleration  of such  Registration
Statement   without  prior  notice  to  such  counsel.   The  sections  of  such
Registration  Statement covering information with respect to the Investors,  the
Investor's  beneficial  ownership of  securities of the Company or the Investors
intended  method of disposition of Registrable  Securities  shall conform to the
information provided to the Company by each of the Investors.

                  k. The Company shall make generally  available to its security
holders as soon as  practicable,  but not later than  ninety (90) days after the
close of the period covered  thereby,  an earnings  statement (in form complying
with  the  provisions  of  Rule  158  under  the  Securities   Act)  covering  a
twelve-month  period  beginning  not later  than the first day of the  Company's
fiscal quarter next following the effective date of the Registration Statement.

                  l. On the date that Registrable Securities are delivered to an
underwriter,  if any, for sale in connection with any Registration Statement or,
if  such  securities  are  not  being  sold by an  underwriter,  on the  date of
effectiveness  thereof and on each Draw Down Date, the Company shall have caused
to be delivered to the Investor (and to each underwriter, if any) (i) an opinion
of the  Company's  independent  counsel in the form of Exhibit G to the Purchase
Agreement,  addressed to the underwriters,  if any, and the Investors and (ii) a
Comfort  Letter or Bring Down  Comfort  Letter  (each as defined in the Purchase
Agreement),  as  applicable,  as required  pursuant to the terms of the Purchase
Agreement, addressed to the underwriters, if any, and the Investors.

                  m. Subject to the  provisions of the Purchase  Agreement,  the
Company  shall make  available  for  inspection  by (i) any  Investor,  (ii) any
underwriter   participating  in  any  disposition  pursuant  to  a  Registration
Statement,  (iii) one firm of  attorneys  and one firm of  accountants  or other
agents retained by the Initial Investor, (iv) one firm of attorneys and one firm
of accountants or other agents retained by all other Investors, and (v) one firm
of attorneys retained by all such underwriters (collectively,  the "Inspectors")
all pertinent financial and other records, and pertinent corporate documents and
properties of the Company (collectively,  the "Records"), as shall be reasonably
deemed  necessary by each Inspector to enable each Inspector to exercise its due
diligence  responsibility,  and  cause the  Company's  officers,  directors  and
employees to supply all information  which any Inspector may reasonably  request
for purposes of such due  diligence;  provided,  however,  that,  subject to the
provisions of the Purchase  Agreement,  each Inspector  shall hold in confidence
and shall not make any disclosure (except to an Investor) of any Record or other
information which the Company  determines in good faith to be confidential,  and
of which determination the Inspectors are so notified, unless (a) the release of
such  Records is ordered  pursuant  to a subpoena or other order from a court or
government body of competent jurisdiction or (b) the information in such Records
has been made  generally  available  to the public other than by  disclosure  in
violation  of this or any  other  agreement.  Nothing  herein  (or in any  other
confidentiality  agreement between the Company and any Investor) shall be deemed
to limit the Investor's ability to sell Registrable Securities in a manner which
is otherwise consistent with applicable laws and regulations.

                  n.  The  Company  shall  hold in  confidence  and not make any
disclosure of information  concerning an Investor provided to the Company unless
(i) disclosure of such  information is necessary to comply with federal or state
securities  laws, (ii) the disclosure of such  information is necessary to avoid
or correct a misstatement or omission in any Registration  Statement,  (iii) the
release of such  information  is ordered  pursuant  to a subpoena or other order
from a court  or  governmental  body of  competent  jurisdiction,  or (iv)  such
information  has been made  generally  available  to the  public  other  than by
disclosure in violation of this or any other agreement.  The Company agrees that
it shall,  upon  learning  that  disclosure  of such  information  concerning an
Investor  is  sought  in  or  by a  court  or  governmental  body  of  competent
jurisdiction  or through other means,  give prompt notice to such Investor prior
to making such disclosure,  and allow the Investor, at its expense, to undertake
appropriate  action to prevent  disclosure  of, or to obtain a protective  order
for, such information.

                  o. The Company shall (i) cause all the Registrable  Securities
covered by the Registration  Statement to be listed on each national  securities
exchange on which  securities  of the same class or series issued by the Company
are then listed,  if any, if the listing of such Registrable  Securities is then
permitted under the rules of such exchange, or (ii) to the extent the securities
of the same  class  or  series  are not then  listed  on a  national  securities
exchange, secure the designation and quotation of all the Registrable Securities
covered by the  Registration  Statement on Nasdaq or, if not eligible for Nasdaq
on the Nasdaq SmallCap and, without limiting the generality of the foregoing, to
arrange for at least two market makers to register with the National Association
of Securities  Dealers,  Inc.  ("NASD") as such with respect to such Registrable
Securities.

                  p. The Company shall provide a transfer  agent and  registrar,
which may be a single entity, for the Registrable  Securities not later than the
effective date of the Registration Statement.

                  q. The Company  shall  cooperate  with the  Investors who hold
Registrable   Securities   being  offered  and  the  managing   underwriter   or
underwriters,  if any, to  facilitate  the timely  preparation  and  delivery of
certificates  (not bearing any  restrictive  legends)  representing  Registrable
Securities to be offered pursuant to such Registration Statement and enable such
certificates to be in such denominations or amounts,  as the case may be, as the
managing  underwriter or  underwriters,  if any, or the Investors may reasonably
request  and   registered  in  such  names  as  the  managing   underwriter   or
underwriters,  if any, or the  Investors  may  request,  and,  within  three (3)
business  days  after  a  Registration   Statement  which  includes  Registrable
Securities is ordered effective by the SEC, the Company shall deliver, and shall
cause legal counsel  selected by the Company to deliver,  to the transfer  agent
for the Registrable  Securities (with copies to the Investors whose  Registrable
Securities  are included in such  Registration  Statement) an instruction in the
form  attached  hereto as Exhibit 1 and an  opinion of such  counsel in the form
attached hereto as Exhibit 2.

                  r. At the request of the holders of a majority-in-interest  of
the Registrable Securities, the Company shall prepare and file with the SEC such
amendments   (including   post-effective   amendments)   and  supplements  to  a
Registration   Statement  and  any  prospectus   used  in  connection  with  the
Registration  Statement  as may be  necessary  in  order to  change  the plan of
distribution set forth in such Registration Statement.

                  s. The Company  shall not,  and shall not agree to,  allow the
holders of any  securities of the Company to include any of their  securities in
any  Registration  Statement  under  Section  2(a)  hereof or any  amendment  or
supplement  thereto under Section 3(b) hereof without the consent of the holders
of a  majority-in-interest  of the  Registrable  Securities.  In  addition,  the
Company  shall not offer any  securities  for its own  account or the account of
others in any Registration  Statement under Section 2(a) hereof or any amendment
or  supplement  thereto  under  Section  3(b) hereof  without the consent of the
holders of a majority-in- interest of the Registrable Securities.

                  t.  The  Company  shall  take  all  other  reasonable  actions
necessary to expedite and facilitate disposition by the Investors of Registrable
Securities pursuant to a Registration Statement.

                  u. The Company shall comply with all  applicable  laws related
to a  Registration  Statement  and  offering  and  sale  of  securities  and all
applicable  rules and  regulations  of  governmental  authorities  in connection
therewith  (including without limitation the Securities Act and the Exchange Act
and the rules and regulations promulgated by the SEC).

         4.       OBLIGATIONS OF THE INVESTORS.

         In connection with the registration of the Registrable Securities,  the
Investors shall have the following obligations:

                  a. It shall be a condition precedent to the obligations of the
Company to complete the registration  pursuant to this Agreement with respect to
the  Registrable  Securities of a particular  Investor that such Investor  shall
furnish to the  Company  such  information  regarding  itself,  the  Registrable
Securities  held by it and the intended method of disposition of the Registrable
Securities held by it as shall be reasonably required to effect the registration
of such  Registrable  Securities  and shall execute such documents in connection
with such registration as the Company may reasonably request. At least seven (7)
business  days prior to the first  anticipated  filing date of the  Registration
Statement, the Company shall notify each Investor of the information the Company
requires from each such Investor.

                  b.  Each  Investor,  by  such  Investor's  acceptance  of  the
Registrable  Securities,  agrees to  cooperate  with the  Company as  reasonably
requested by the Company in connection  with the  preparation  and filing of the
Registration Statements hereunder, unless such Investor has notified the Company
in  writing  of such  Investor's  election  to  exclude  all of such  Investor's
Registrable Securities from the Registration Statements.

                  c. In the event Investors  holding a  majority-in-interest  of
the Registrable  Securities  being  registered (with the approval of the Initial
Investor)  determine to engage the  services of an  underwriter,  each  Investor
agrees  to  enter  into  and  perform  such  Investor's   obligations  under  an
underwriting  agreement,  in  usual  and  customary  form,  including,   without
limitation,  customary  indemnification and contribution  obligations,  with the
managing  underwriter  of such  offering  and take  such  other  actions  as are
reasonably  required in order to expedite or facilitate  the  disposition of the
Registrable Securities, unless such Investor has notified the Company in writing
of such  Investor's  election  to  exclude  all of such  Investor's  Registrable
Securities from such Registration Statement.

                  d. Each Investor  agrees that, upon receipt of any notice from
the Company of the happening of any event of the kind described in Sections 3(g)
or 3(i), such Investor will immediately  discontinue  disposition of Registrable
Securities  pursuant to the  Registration  Statement  covering such  Registrable
Securities  until such Investor's  receipt of the copies of the  supplemented or
amended prospectus  contemplated by Sections 3(g) or 3(i) and, if so directed by
the Company,  such Investor  shall deliver to the Company (at the expense of the
Company) or destroy (and deliver to the Company a  certificate  of  destruction)
all  copies in such  Investor's  possession,  of the  prospectus  covering  such
Registrable Securities current at the time of receipt of such notice.

                  e.  No   Investor   may   participate   in  any   underwritten
registration  hereunder  unless such Investor (i) agrees to sell such Investor's
Registrable Securities on the basis provided in any underwriting arrangements in
usual and  customary  form  entered  into by the  Company,  (ii)  completes  and
executes  all  questionnaires,  powers of  attorney,  indemnities,  underwriting
agreements  and  other  documents  reasonably  required  under the terms of such
underwriting  arrangements,  and (iii)  agrees to pay its pro rata  share of all
underwriting  discounts  and  commissions  and any  expenses  in excess of those
payable by the Company pursuant to Section 5 below.

         5.       EXPENSES OF REGISTRATION.

         All  reasonable  expenses,   other  than  underwriting   discounts  and
commissions,   incurred   in   connection   with   registrations,   filings   or
qualifications pursuant to Sections 2 and 3, including,  without limitation, all
registration,  listing and qualification fees, printers and accounting fees, the
fees and  disbursements of counsel for the Company,  and the reasonable fees and
disbursements  of one  counsel  selected  by the  Initial  Investor  pursuant to
Sections 2(b) and 3(j) hereof shall be borne by the Company; provided,  however,
that such  reasonable  fees and  disbursements  of the  counsel  selected by the
Initial  Investors shall be subject to the limitation on  reimbursable  expenses
set forth in Section 5.6 of the Purchase Agreement.

         6.       INDEMNIFICATION.

         In the event any Registrable  Securities are included in a Registration
Statement under this Agreement:

                  a. To the extent permitted by law, the Company will indemnify,
hold  harmless  and  defend  (i)  each  Investor  who  holds  such   Registrable
Securities, (ii) the directors,  officers, partners,  employees, agents and each
person who controls any Investor within the meaning of the Securities Act or the
Securities  Exchange Act of 1934, as amended (the "Exchange Act"), if any, (iii)
any underwriter  (as defined in the Securities Act) for the Investors,  and (iv)
the directors,  officers,  partners,  employees and each person who controls any
such  underwriter  within the meaning of the Securities Act or the Exchange Act,
if any (each,  an  "Indemnified  Person"),  against any joint or several losses,
claims, damages,  liabilities or expenses (collectively,  together with actions,
proceedings  or inquiries by any  regulatory  or  self-regulatory  organization,
whether commenced or threatened,  in respect thereof,  "Claims") to which any of
them may become  subject  insofar as such Claims arise out of or are based upon:
(i) any untrue  statement or alleged  untrue  statement of a material  fact in a
Registration  Statement or the omission or alleged  omission to state  therein a
material fact required to be stated or necessary to make the statements  therein
not  misleading;  (ii) any untrue  statement  or alleged  untrue  statement of a
material  fact  contained  in any  preliminary  prospectus  if used prior to the
effective  date  of such  Registration  Statement,  or  contained  in the  final
prospectus  (as  amended or  supplemented,  if the Company  files any  amendment
thereof or supplement  thereto with the SEC) or the omission or alleged omission
to state  therein  any  material  fact  necessary  to make the  statements  made
therein,  in light of the circumstances  under which the statements therein were
made, not misleading; or (iii) any violation or alleged violation by the Company
of the  Securities  Act, the Exchange  Act,  any other law,  including,  without
limitation,  any state  securities  law,  or any rule or  regulation  thereunder
relating to the offer or sale of the Registrable  Securities (the matters in the
foregoing clauses (i) through (iii) being, collectively,  "Violations"). Subject
to the  restrictions  set forth in  Section  6(c) with  respect to the number of
legal counsel,  the Company shall reimburse the Indemnified Person,  promptly as
such  expenses are incurred and are due and payable,  for any  reasonable  legal
fees  or  other  reasonable   expenses  incurred  by  them  in  connection  with
investigating  or  defending  any such  Claim.  Notwithstanding  anything to the
contrary  contained  herein,  the  indemnification  agreement  contained in this
Section  6(a):  (i) shall not apply to a Claim  arising  out of or based  upon a
Violation  which  occurs in reliance  upon and in  conformity  with  information
furnished in writing to the Company by any Indemnified Person or underwriter for
such Indemnified  Person expressly for use in connection with the preparation of
such Registration Statement or any such amendment thereof or supplement thereto;
(ii)  shall  not  apply  to  amounts  paid in  settlement  of any  Claim if such
settlement is effected  without the prior written consent of the Company,  which
consent  shall not be  unreasonably  withheld;  and (iii)  with  respect  to any
preliminary prospectus, shall not inure to the benefit of any Indemnified Person
if  the  untrue  statement  or  omission  of  material  fact  contained  in  the
preliminary  prospectus  was corrected on a timely basis in the  prospectus,  as
then  amended  or  supplemented,  such  corrected  prospectus  was  timely  made
available by the Company  pursuant to Section 3(d) hereof,  and the  Indemnified
Person was promptly advised in writing not to use the incorrect prospectus prior
to  the  use  giving  rise  to  a  Violation   and  such   Indemnified   Person,
notwithstanding  such advice, used it. Such indemnity shall remain in full force
and  effect  regardless  of  any  investigation  made  by or on  behalf  of  the
Indemnified Person and shall survive the transfer of the Registrable  Securities
by the Investors pursuant to Section 9.

                  b. In connection with any  Registration  Statement in which an
Investor is  participating,  each such Investor agrees severally and not jointly
to  indemnify,  hold  harmless  and  defend,  to the same extent and in the same
manner set forth in Section 6(a), the Company,  each of its  directors,  each of
its  officers who signs the  Registration  Statement,  each person,  if any, who
controls the Company  within the meaning of the  Securities  Act or the Exchange
Act, any underwriter and any other stockholder  selling  securities  pursuant to
the Registration Statement or any of its directors or officers or any person who
controls such  stockholder or  underwriter  within the meaning of the Securities
Act or the Exchange Act (collectively  and together with an Indemnified  Person,
an  "Indemnified  Party"),  against  any Claim to which  any of them may  become
subject,  under the  Securities  Act, the Exchange Act or otherwise,  insofar as
such Claim  arises out of or is based upon any  Violation by such  Investor,  in
each case to the extent (and only to the extent) that such  Violation  occurs in
reliance  upon and in  conformity  with  written  information  furnished  to the
Company by such Investor  expressly for use in connection with such Registration
Statement; and subject to Section 6(c) such Investor will reimburse any legal or
other expenses  (promptly as such expenses are incurred and are due and payable)
reasonably  incurred by them in connection with  investigating  or defending any
such Claim;  provided,  however,  that the indemnity agreement contained in this
Section 6(b) shall not apply to amounts paid in  settlement of any Claim if such
settlement is effected without the prior written consent of such Investor, which
consent shall not be unreasonably withheld; provided, further, however, that the
Investor shall be liable under this Agreement  (including  this Section 6(b) and
Section  7) for only that  amount as does not exceed  the net  proceeds  to such
Investor  as a result of the sale of  Registrable  Securities  pursuant  to such
Registration  Statement.  Such  indemnity  shall remain in full force and effect
regardless of any  investigation  made by or on behalf of such Indemnified Party
and shall  survive the transfer of the  Registrable  Securities by the Investors
pursuant  to Section  9.  Notwithstanding  anything  to the  contrary  contained
herein,  the  indemnification  agreement  contained  in this  Section  6(b) with
respect  to any  preliminary  prospectus  shall not inure to the  benefit of any
Indemnified Party if the untrue statement or omission of material fact contained
in the preliminary prospectus was corrected on a timely basis in the prospectus,
as then amended or supplemented.

                  c.  Promptly  after  receipt  by  an  Indemnified   Person  or
Indemnified  Party  under this  Section 6 of notice of the  commencement  of any
action  (including  any  governmental   action),   such  Indemnified  Person  or
Indemnified Party shall, if a Claim in respect thereof is to be made against any
indemnifying  party under this  Section 6, deliver to the  indemnifying  party a
written notice of the commencement  thereof,  and the  indemnifying  party shall
have the right to participate in, and, to the extent the  indemnifying  party so
desires,  jointly with any other indemnifying party similarly noticed, to assume
control  of the  defense  thereof  with  counsel  mutually  satisfactory  to the
indemnifying  party and the Indemnified  Person or the Indemnified Party, as the
case may be; provided,  however, that an Indemnified Person or Indemnified Party
shall have the right to retain its own counsel  with the fees and expenses to be
paid by the  indemnifying  party,  if,  in the  reasonable  opinion  of  counsel
retained by the indemnifying  party, the  representation  by such counsel of the
Indemnified  Person or  Indemnified  Party and the  indemnifying  party would be
inappropriate  due to actual  or  potential  differing  interests  between  such
Indemnified  Person or Indemnified Party and any other party represented by such
counsel  in such  proceeding.  The  indemnifying  party  shall  pay for only one
separate legal counsel for the Indemnified  Persons or the Indemnified  Parties,
as applicable,  and such legal counsel shall be selected by Investors  holding a
majority-in-interest  of the Registrable Securities included in the Registration
Statement   to   which   the   Claim   relates   (with   the   approval   of   a
majority-in-interest  of the Initial Investor), if the Investors are entitled to
indemnification  hereunder,  or the  Company,  if the  Company  is  entitled  to
indemnification  hereunder, as applicable. The failure to deliver written notice
to the  indemnifying  party within a reasonable time of the  commencement of any
such action shall not relieve such  indemnifying  party of any  liability to the
Indemnified  Person or  Indemnified  Party  under this  Section 6, except to the
extent  that the  indemnifying  party is actually  prejudiced  in its ability to
defend such action. The indemnification required by this Section 6 shall be made
by  periodic   payments  of  the  amount   thereof  during  the  course  of  the
investigation or defense, as such expense, loss, damage or liability is incurred
and is due and payable.

         7.       CONTRIBUTION.

         To  the  extent  any   indemnification  by  an  indemnifying  party  is
prohibited or limited by law, the indemnifying  party agrees to make the maximum
contribution  with respect to any amounts for which it would otherwise be liable
under Section 6 to the fullest extent permitted by law; provided,  however, that
(i) no contribution shall be made under  circumstances where the maker would not
have been  liable for  indemnification  under the fault  standards  set forth in
Section  6, (ii) no  seller  of  Registrable  Securities  guilty  of  fraudulent
misrepresentation  (within the meaning of Section 11(f) of the  Securities  Act)
shall be entitled to contribution from any seller of Registrable  Securities who
was not  guilty of such  fraudulent  misrepresentation,  and (iii)  contribution
(together with any indemnification or other obligations under this Agreement) by
any  seller of  Registrable  Securities  shall be  limited  in amount to the net
amount of proceeds  received  by such  seller from the sale of such  Registrable
Securities.

         8.       REPORTS UNDER THE EXCHANGE ACT.

         With a view to making  available to the  Investors the benefits of Rule
144 or any  other  similar  rule or  regulation  of the SEC that may at any time
permit the  investors to sell  securities  of the Company to the public  without
registration, the Company agrees to:

                  a. make and keep public information  available, as those terms
are understood and defined in Rule 144;

                  b. file with the SEC in a timely  manner all reports and other
documents  required of the Company under the Securities Act and the Exchange Act
so long as the Company remains subject to such requirements (it being understood
that nothing herein shall limit the Company's  obligations  under Section 5.3 of
the Purchase  Agreement)  and the filing of such reports and other  documents is
required for the applicable provisions of Rule 144; and

                  c.  furnish to each  Investor  so long as such  Investor  owns
Registrable  Securities,  promptly upon request,  (i) a written statement by the
Company that it has complied  with the reporting  requirements  of Rule 144, the
Securities  Act and the Exchange  Act,  (ii) a copy of the most recent annual or
quarterly report of the Company and such other reports and documents so filed by
the Company,  and (iii) such other information as may be reasonably requested to
permit  the  Investors  to sell such  securities  pursuant  to Rule 144  without
registration.

         9.       ASSIGNMENT OF REGISTRATION RIGHTS.

         The rights under this Agreement  shall be  automatically  assignable by
the Investors to any transferee of all or any portion of Registrable  Securities
if: (i) the Investor agrees in writing with the transferee or assignee to assign
such rights,  and a copy of such  agreement is furnished to the Company within a
reasonable time after such assignment,  (ii) the Company is, within a reasonable
time after such transfer or assignment, furnished with written notice of (a) the
name and address of such  transferee or assignee,  and (b) the  securities  with
respect to which such  registration  rights are being  transferred  or assigned,
(iii)  following  such transfer or assignment,  the further  disposition of such
securities by the transferee or assignee is restricted  under the Securities Act
and applicable  state  securities  laws,  (iv) at or before the time the Company
receives the written notice  contemplated  by clause (ii) of this sentence,  the
transferee or assignee  agrees in writing with the Company to be bound by all of
the  provisions  contained  herein,  (v) such  transfer  shall have been made in
accordance with the applicable requirements of the Purchase Agreement,  and (vi)
such transferee  shall be an "accredited  investor" as that term defined in Rule
501 of Regulation D promulgated under the Securities Act.

         10.      AMENDMENT OF REGISTRATION RIGHTS.

         Provisions of this Agreement may be amended and the observance  thereof
may  be  waived  (either  generally  or  in a  particular  instance  and  either
retroactively or prospectively),  only with written consent of the Company,  the
Initial  Investor (to the extent such Initial  Investor  still owns  Registrable
Securities)  and  Investors  who hold a  majority  interest  of the  Registrable
Securities.  Any amendment or waiver effected in accordance with this Section 10
shall be binding upon each Investor and the Company.

         11.      MISCELLANEOUS.

                  a. A person or entity is deemed to be a holder of  Registrable
Securities  whenever  such  person or entity  owns of  record  such  Registrable
Securities.  If  the  Company  receives  conflicting  instructions,  notices  or
elections  from  two or more  persons  or  entities  with  respect  to the  same
Registrable  Securities,  the Company shall act upon the basis of  instructions,
notice  or  election  received  from the  registered  owner of such  Registrable
Securities.

                  b. Any  notices  required or  permitted  to be given under the
terms  hereof  shall be sent by certified  or  registered  mail (return  receipt
requested)  or  delivered  personally  or by  courier  (including  a  recognized
overnight  delivery  service) or by facsimile  and shall be effective  five days
after being placed in the mail, if mailed by regular United States mail, or upon
receipt, if delivered personally or by courier (including a recognized overnight
delivery  service)  or by  facsimile,  in each case  addressed  to a party.  The
addresses for such communications shall be:

                           If to the Company:

                           Teligent, Inc.
                           8065 Leesburg Pike, Suite 400
                           Vienna, Virginia   22182
                           Attention: General Counsel
                           Facsimile: (703) 762-5177

                           With copy to:

                           Cravath, Swaine & Moore
                           825 Eighth Avenue
                           New York, New York 10019
                           Attention:  Scott A. Barshay, Esq.
                           Facsimile: (212) 474-3700

If  to  an Investor: to the address set forth immediately below such  Investor's
name on the signature pages to the Purchase Agreement.

                           With copy to:

                           Bradley D. Houser, Esq.
                           Akerman, Senterfitt & Eidson, P.A.
                           One Southeast Third Avenue, 28th Floor
                           Miami, Florida 33131
                           Facsimile:  (305) 374-5095

                  c.  Failure of any party to exercise any right or remedy under
this  Agreement or otherwise,  or delay by a party in  exercising  such right or
remedy, shall not operate as a waiver thereof.

                  d.  This  Agreement  shall be  governed  by and  construed  in
accordance with the laws of the State of Delaware  applicable to agreements made
and to be performed in the State of Delaware  (without  regard to  principles of
conflict  of  laws).   Both  parties   irrevocably   consent  to  the  exclusive
jurisdiction of the United States federal courts and the state courts located in
Delaware with respect to any suit or  proceeding  based on or arising under this
Agreement,   the  agreements   entered  into  in  connection   herewith  or  the
transactions  contemplated  hereby or  thereby  and  irrevocably  agree that all
claims in respect of such suit or  proceeding  may be determined in such courts.
Both  parties  irrevocably  waive the  defense of an  inconvenient  forum to the
maintenance of such suit or proceeding.  Both parties further agree that service
of  process  upon a party  mailed by first  class  mail shall be deemed in every
respect  effective  service  of  process  upon the  party  in any  such  suit or
proceeding. Nothing herein shall affect either party's right to serve process in
any  other  manner   permitted  by  law.   Both  parties   agree  that  a  final
non-appealable  judgment in any such suit or proceeding  shall be conclusive and
may be enforced in other  jurisdictions by suit on such judgment or in any other
lawful manner.

                  e. This  Agreement,  the Purchase  Agreement  and the Warrants
(including all schedules and exhibits  hereto or thereto)  constitute the entire
agreement among the parties hereto with respect to the subject matter hereof and
thereof. There are no restrictions,  promises, warranties or undertakings, other
than those set forth or  referred to herein and  therein.  This  Agreement,  the
Purchase   Agreement  and  the  Warrants  supersede  all  prior  agreements  and
understandings  among the  parties  hereto with  respect to the  subject  matter
hereof and thereof.

                  f.  Subject  to the  requirements  of  Section 9 hereof,  this
Agreement  shall inure to the benefit of and be binding upon the  successors and
assigns of each of the parties hereto.

                  g. The  headings  in this  Agreement  are for  convenience  of
reference only and shall not limit or otherwise affect the meaning hereof.

                  h. 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  agreement.  This  Agreement,  once  executed  by a  party,  may be
delivered to the other party hereto by facsimile  transmission of a copy of this
Agreement bearing the signature of the party so delivering this Agreement.

                  i. Each party  shall do and  perform,  or cause to be done and
performed,  all such further acts and things,  and shall execute and deliver all
such other  agreements,  certificates,  instruments and documents,  as the other
party may reasonably request in order to carry out the intent and accomplish the
purposes of this Agreement and the consummation of the transactions contemplated
hereby.

                  j. Except as otherwise provided herein, all consents and other
determinations  to be made by the Investors  pursuant to this Agreement shall be
made by Investors holding a majority of the Registrable Securities.

                  k.  The  Company  acknowledges  that  a  breach  by it of  its
obligations  hereunder will cause irreparable harm to each Investor by vitiating
the intent and purpose of the transactions contemplated hereby. Accordingly, the
Company  acknowledges  that the  remedy  at law for  breach  of its  obligations
hereunder will be inadequate and agrees,  in the event of a breach or threatened
breach by the Company of any of the  provisions  hereunder,  that each  Investor
shall be  entitled,  in  addition to all other  available  remedies in law or in
equity,  to an  injunction  or  injunctions  to prevent or cure  breaches of the
provisions  of  this  Agreement  and  to  enforce  specifically  the  terms  and
provisions  hereof,  without the necessity of showing  economic loss and without
any bond or other security being required.

                  l. The language  used in this  Agreement  will be deemed to be
the language chosen by the parties to express their mutual intent,  and no rules
of strict construction will be applied against any party.

                  m. In the  event  that  any  provision  of this  Agreement  is
invalid or unenforceable  under any applicable statute or rule of law, then such
provision  shall  be  deemed  inoperative  to the  extent  that it may  conflict
therewith  and shall be deemed  modified to conform with such statute or rule of
law. Any provision hereof which may prove invalid or unenforceable under any law
shall not affect the validity or enforceability of any other provision hereof.

                  n. The initial  number of Registrable  Securities  included in
any  Registration  Statement  and each  increase  to the  number of  Registrable
Securities  included  therein  shall be allocated  pro rata among the  Investors
based on the number of Registrable  Securities held by each Investor at the time
of such establishment or increase,  as the case may be. In the event an Investor
shall sell or otherwise  transfer any of such holder's  Registrable  Securities,
each  transferee  shall  be  allocated  a pro  rata  portion  of the  number  of
Registrable Securities included in a Registration Statement for such transferor.
Any shares of Common Stock included on a Registration Statement and which remain
allocated to any person or entity which does not hold any Registrable Securities
shall be allocated to the remaining  Investors,  pro rata based on the number of
shares of Registrable Securities then held by such Investors.

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<PAGE>
                  IN WITNESS  WHEREOF,  the Company and the undersigned  Initial
Investor  have caused this  Agreement  to be duly  executed as of the date first
above written.

TELIGENT, INC.


By: /s/ Alex J. Mandl
    ----------------------------------
         Alex J. Mandl,
         Chief Executive Officer

RGC INTERNATIONAL INVESTORS, LDC

By:      Rose Glen Capital Management, L.P., Investment Manager
         By:      RGC General Partner Corp., as General Partner

By: /s/ Wayne D. Bloch
    ----------------------------------
         Wayne D. Bloch
         Managing Director