Document:

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                                                                   Exhibit 10.12

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                                     WARRANT
                          REGISTRATION RIGHTS AGREEMENT

                           AMERICAN TOWER CORPORATION

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             Warrants to Purchase 11,389,012 Shares of Common Stock

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                          Dated as of January 29, 2003

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                         CREDIT SUISSE FIRST BOSTON LLC
                              GOLDMAN, SACHS & CO.

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     This Warrant Registration Rights Agreement (this "Agreement") is made and
entered into as of January 29, 2003, between American Tower Corporation, a
Delaware corporation (the "Company"), and Credit Suisse First Boston LLC and
Goldman, Sachs & Co. (each an "Initial Purchaser" and collectively, the "Initial
Purchasers"), which have agreed to purchase the Warrants of the Company issued
pursuant to the Warrant Agreement (the "Warrant Agreement"), dated as of the
date hereof, between the Company and The Bank of New York, as warrant agent (the
"Warrant Agent").

     The Warrants are being issued and sold in connection with the offering by
American Tower Escrow Corporation, which is expected to merge with and into
American Towers, Inc. (together, "American Towers") of 808,000 Units each
consisting of (i) $1,000 principal amount at maturity of 12.25% Senior
Subordinated Discount Notes due 2008 (the "Notes") of American Towers, issued
pursuant to the Indenture, dated as of January 29, 2003 among American Towers,
the Guarantors named therein (from and after the consummation of the Escrow
Corp. Merger) and The Bank of New York, as trustee (the "Indenture") and (ii)
one Warrant to purchase 14.0953 fully paid and non-assessable shares of the
Company's Class A common stock (the "Warrant Shares").

     This Agreement is made pursuant to the Purchase Agreement, dated January
22, 2003 (the "Purchase Agreement"), by and among American Towers, the
Guarantors (as defined in the Purchase Agreement) (from and after the
consummation of the Escrow Corp. Merger) and the Initial Purchasers. In order to
induce the Initial Purchasers to purchase the Warrants, the Company has agreed
to provide the registration rights set forth in this Agreement. The execution
and delivery of this Agreement is a condition to the obligations of the Initial
Purchasers set forth in Section 6(g) of the Purchase Agreement. Capitalized
terms used herein and not otherwise defined shall have the meaning assigned to
them in the Warrant Agreement.

     The parties hereby agree as follows:

1. DEFINITIONS

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

     Act: The Securities Act of 1933, as amended.

     Affiliate: As defined in Rule 144.

     Black Out Notice: As defined in Section 5(b) hereof.

     Black Out Period: As defined in Section 3(a) hereof.

     Closing Date: The date hereof.

     Commission: The Securities and Exchange Commission.

     Escrow Corp:. means American Tower Escrow Corporation, a Delaware
corporation.

     Escrow Corp. Merger: means the merger transaction involving Escrow Corp.
and American Towers, Inc. pursuant to the Escrow Corp. Merger Agreement.

     Escrow Corp. Merger Agreement: means an Agreement and Plan of Merger with
respect to the Escrow Crop. Merger, dated as of the date of the Indenture.

     Exchange Act: The Securities Exchange Act of 1934, as amended.

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     Holders: As defined in Section 2 hereof.

     Majority Holders: shall mean, on any date, Holders of a majority of the
aggregate amount of Warrants registered under a Registration Statement.

     Notice and Questionnaire: shall mean a written notice delivered to the
Company substantially in the form attached as Annex A hereto.

     Notice Holder: shall mean, on any date, any Holder of Transfer Restricted
Securities that has delivered a Notice and Questionnaire to the Company on or
prior to such date.

     Prospectus: The prospectus included in a Registration Statement at the time
such Registration Statement is declared effective, as amended or supplemented by
any prospectus supplement and by all other amendments thereto, including
post-effective amendments, and all material incorporated by reference into such
Prospectus.

     Registration Default: shall have the meaning assigned in Section 6 hereof.

     Registration Statement: Any registration statement of the Company relating
to the registration for resale of Transfer Restricted Securities and the
issuance of the Company's Class A common stock upon the exercise of the Warrants
resold pursuant to the Registration Statement that is filed pursuant to the
provisions of this Agreement and including the Prospectus included therein, all
amendments and supplements thereto (including post-effective amendments) and all
exhibits and material incorporated by reference therein.

     Rule 144: Rule 144 promulgated under the Act.

     Selling Holder: a Holder who is selling Transfer Restricted Securities
pursuant to Section 3 hereof.

     Transfer Restricted Securities: (a) Each Warrant and Warrant Share held by
an Affiliate of the Company and (b) each other Warrant and Warrant Share until
the earlier to occur of (i) the date on which such Warrant or Warrant Share
(other than any Warrant Share issued upon exercise of a Warrant in accordance
with a Registration Statement) has been disposed of in accordance with a
Registration Statement and (ii) the date on which such Warrant or Warrant Share
(or the related Warrant) is distributed to the public pursuant to Rule 144 under
the Act.

2. HOLDERS

     A Person is deemed to be a holder of Transfer Restricted Securities (each,
a "Holder") whenever such Person is the holder of record of Transfer Restricted
Securities.

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3. SHELF REGISTRATION

     (a)  Shelf Registration. The Company shall prepare and cause to be filed
with the Commission on or before 90 days from the Closing Date pursuant to Rule
415 under the Securities Act a Registration Statement on the appropriate form
relating to resales of Transfer Restricted Securities by the Holders thereof and
issuance of the Company's Class A common stock upon the exercise of the Warrants
resold pursuant to such registration statement. The Company shall use its
reasonable best efforts to cause the Registration Statement to be declared
effective by the Commission, subject to certain exceptions discussed herein, on
or before 180 days after the Closing Date.

     (b)  To the extent necessary to ensure that the Registration Statement is
available for sales of Transfer Restricted Securities by the Holders thereof
entitled to the benefit of Section 3(a) hereof, the Company shall use its
reasonable best efforts to keep any Registration Statement required by Section
3(a) hereof continuously effective, supplemented, amended and current as
required by and subject to the provisions of Sections 3(c) and 5(a) hereof and
in conformity with the requirements of this Agreement, the Act and the policies,
rules and regulations of the Commission as announced from time to time, until
the second anniversary of the date hereof; provided that such obligation shall
expire before such date if the Company delivers to the Warrant Agent a written
opinion of counsel to the Company (which opinion of counsel shall be
satisfactory to the Company) that all Holders (other than Affiliates of the
Company) of Warrants and Warrant Shares may resell the Warrants and the Warrant
Shares without registration under the Act and without restriction as to the
manner, timing or volume of any such sale; and provided, further, that
notwithstanding the foregoing, any Affiliate of the Company may, with notice to
the Company, require the Company to keep the Registration Statement continuously
effective for resales by such Affiliate for so long as such Affiliate holds
Warrants or Warrant Shares, including as a result of any market-making
activities or other trading activities of such Affiliate.

     (c)  Notwithstanding the foregoing, the Company shall not be required to
amend or supplement the Registration Statement, any related prospectus or any
document incorporated therein by reference and may suspend the availability of
the Registration Statement, for a period (a "Black Out Period") not to exceed,
for so long as this Agreement is in effect, an aggregate of 60 days in any
calendar year, (i) upon the occurrence or existence of any pending corporate
development or any other material event as a result of which the Registration
Statement, any related prospectus or any document incorporated therein by
reference as then amended or supplemented would, in the Company's good faith
judgment, contain an untrue statement of a material fact or omit to state a
material fact necessary in order to make the statements therein, in the light of
the circumstances under which they were made, not misleading, and (ii)(A) the
Company determines in good faith and in its sole judgment that the disclosure of
such event at such time would not be in the best interests of the Company or (B)
the disclosure otherwise relates to a material business transaction which has
not yet been publicly disclosed; provided that such Black Out Period shall be
extended for any period, not to exceed an aggregate of 30 days in any calendar
year, during which the Commission is reviewing any proposed amendment or
supplement to the Registration Statement, any related prospectus or any document
incorporated therein by reference which has been filed by the Company.

4. HOLDER INFORMATION

     No Holder of Transfer Restricted Securities may include any of its Transfer
Restricted Securities in any Registration Statement pursuant to this Agreement
unless and until such Holder furnishes to the Company in writing, within 20 days
after receipt of a request therefor substantially in the form of the Notice and
Questionnaire, the information specified in Item 507 or 508 of Regulation S-K,
as applicable, of the Act for use in connection with any Registration Statement
or Prospectus or preliminary Prospectus

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included therein. Each selling Holder agrees to promptly furnish additional
information required to be disclosed in order to make the information previously
furnished to the Company by such Holder not materially misleading.

5. REGISTRATION PROCEDURES

     (a)  In connection with the Registration Statement and any related
Prospectus required by this Agreement, the Company shall:

               (i)   use its reasonable best efforts to effect such registration
     to permit the sale of the Transfer Restricted Securities being sold in
     accordance with the intended method or methods of distribution thereof, and
     pursuant thereto the Company will prepare and file with the Commission a
     Registration Statement relating to the registration on any appropriate form
     under the Act, which form shall be available for the sale of the Transfer
     Restricted Securities in accordance with the intended method or methods of
     distribution thereof within the time periods and otherwise in accordance
     with the provisions hereof;

               (ii)  use its reasonable best efforts to keep such Registration
     Statement continuously effective and provide or incorporate by reference
     all requisite financial statements for the period specified in Section 3 of
     this Agreement. Upon the occurrence of any event that would cause any such
     Registration Statement or the Prospectus contained therein (A) to contain
     an untrue statement of material fact or omit to state any material fact
     necessary to make the statements therein, in the light of the circumstances
     under which they were made, not misleading or (B) not to be effective and
     usable for resale of Transfer Restricted Securities during the period
     required by this Agreement, the Company shall, except to the extent
     permitted by Section 3(c) hereof, file promptly an appropriate amendment to
     such Registration Statement or a supplement to the Prospectus, as
     applicable, curing such defect, and, in the case of an amendment, use its
     reasonable best efforts to cause such amendment to be declared effective as
     soon as practicable;

               (iii) prepare and file with the Commission such amendments and
     post-effective amendments to the applicable Registration Statement as may
     be necessary to keep such Registration Statement effective for the
     applicable period set forth in Section 3 hereof; cause the Prospectus to be
     supplemented by any required Prospectus supplement, and as so supplemented
     to be filed pursuant to Rule 424 under the Act, and to comply fully with
     Rules 424, 430A and 462, as applicable, under the Act in a timely manner;
     and comply with the provisions of the Act with respect to the disposition
     of all securities covered by such Registration Statement during the
     applicable period in accordance with the intended method or methods of
     distribution by the sellers thereof set forth in such Registration
     Statement or supplement to the Prospectus;

               (iv)  advise the Notice Holders promptly and, if requested by the
     Notice Holders, confirm such advice in writing, (A) when the Prospectus or
     any Prospectus supplement or post-effective amendment has been filed, and,
     with respect to any applicable Registration Statement or any post-effective
     amendment thereto, when the same has become effective, (B) of any request
     by the Commission for amendments to the Registration Statement or
     amendments or supplements to the Prospectus or for additional information
     relating thereto, (C) of the issuance by the Commission of any stop order
     suspending the effectiveness of the Registration Statement under the Act or
     of the suspension by any state securities commission of the qualification
     of the Transfer Restricted Securities for offering or sale in any
     jurisdiction, or the initiation of any proceeding for any of the preceding
     purposes, and (D) of the existence of any fact or the happening of any
     event that makes any statement of a material fact made in the

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     Registration Statement, the Prospectus, any amendment or supplement thereto
     or any document incorporated by reference therein untrue, or that requires
     the making of any additions to or changes in the Registration Statement in
     order to make the statements therein not misleading, or that requires the
     making of any additions to or changes in the Prospectus in order to make
     the statements therein, in the light of the circumstances under which they
     were made, not misleading. If at any time the Commission shall issue any
     stop order suspending the effectiveness of the Registration Statement, or
     any state securities commission or other regulatory authority shall issue
     an order suspending the qualification or exemption from qualification of
     the Transfer Restricted Securities under state securities or Blue Sky laws,
     the Company shall use its reasonable best efforts to obtain the withdrawal
     or lifting of such order at the earliest possible time;

               (v)    subject to Section 3(c) hereof, if any fact or event
     contemplated by Section 5(a)(iv)(D) hereof shall exist or have occurred,
     prepare a supplement or post-effective amendment to the Registration
     Statement or related Prospectus or any document incorporated therein by
     reference or file any other required document so that, as thereafter
     delivered to the purchasers of Transfer Restricted Securities, the
     Prospectus will not contain an untrue statement of a material fact or omit
     to state any material fact necessary to make the statements therein, in the
     light of the circumstances under which they were made, not misleading;

               (vi)   before filling any Registration Statement or Prospectus or
     any amendments or supplements thereto (including all documents incorporated
     by reference after the initial filing of such Registration Statement)
     furnish to and afford such Holder and such Holder's counsel, if any, a
     reasonable opportunity to review copies of all such documents proposed to
     be filed (in each case, where possible, at least five Business Days prior
     to such filing, or such later date as is reasonable under the
     circumstances), and shall incorporate into such filings such comments and
     changes as may be reasonably requested by such persons. The provisions of
     this Section 4(a) shall not apply to the filing by the Company of annual,
     quarterly or current reports, or proxy statements or schedules under the
     Exchange Act. The Company shall not file any Registration Statement or
     Prospectus or any amendments or supplements thereto if Holders of the
     Majority Holders covered by such Registration Statement or their counsel,
     shall reasonably and in a timely manner object.

               (vii)  Make available at reasonable times for inspection by one
     or more representatives of the Selling Holders, designated in writing by a
     Majority of Holders whose Transfer Restricted Securities are included in
     the Registration Statement, and any attorney or accountant retained by such
     Selling Holders, all financial and other records, pertinent corporate
     documents and properties of the Company as shall be reasonably necessary to
     enable them to conduct a reasonable investigation within the meaning of
     Section 11 of the Securities Act, and cause the Company's officers,
     directors, managers and employees to supply all information reasonably
     requested by any such representative or representatives of the Selling
     Holders, attorney or accountant in connection therewith; provided, however,
     that any information that is designated in writing by the Company, in good
     faith, as confidential at the time of delivery of such information shall be
     kept confidential by the Selling Holders or any such underwriter, attorney,
     accountant or agent, unless such disclosure is made in connection with a
     court proceeding or required by law, or such information becomes available
     to the public generally or through a third party without an accompanying
     obligation of confidentiality;

               (viii) if requested by the Selling Holders, promptly include in
     any Registration Statement or Prospectus, pursuant to a supplement or
     post-effective amendment if necessary, such information as the Selling
     Holders may reasonably request to have included therein, including, without
     limitation, information relating to the "Plan of Distribution" of the

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     Transfer Restricted Securities and the use of the Registration Statement or
     Prospectus for market-making activities; and make all required filings of
     such Prospectus supplement or post-effective amendment as soon as
     practicable after the Company is notified of the matters to be included in
     such Prospectus supplement or post-effective amendment;

               (ix)   furnish to each Selling Holder and each Holder upon
     request, without charge, at least one copy of the Registration Statement,
     as first filed with the Commission, and of each amendment;

               (x)    deliver to the underwriters, if any, and each Holder,
     without charge, as many copies of the Prospectus (including each
     preliminary prospectus) and any amendment or supplement thereto as the
     underwriters, if any, or such Selling Holder reasonably may request; the
     Company hereby consents to the use (in accordance with law) of the
     Prospectus and any amendment or supplement thereto by each selling Person
     in connection with the offering and the sale of the Transfer Restricted
     Securities covered by the Prospectus or any amendment or supplement thereto
     and all market-making activities of the underwriters, if any, as the case
     may be;

               (xi)   enter into such agreements (including underwriting
     agreements) and make such representations and warranties and take all such
     other actions in connection therewith in order to expedite or facilitate
     the disposition of the Transfer Restricted Securities pursuant to any
     applicable Registration Statement contemplated by this Agreement as may be
     reasonably requested by the Selling Holders in connection with any sale or
     resale pursuant to any applicable Registration Statement. In such
     connection, the Company shall:

               (A)  if requested by the Majority Holders, furnish (or, in the
          case of paragraphs (2) and (3), use its reasonable best efforts to
          cause to be furnished) to the Selling Holders, upon the effectiveness
          of the Registration Statement:

                    (1) a certificate, dated such date, signed on behalf of the
               Company by (x) the President or any Vice President and (y) a
               principal financial or accounting officer of the Company,
               confirming, as of the date thereof, the matters set forth in
               Sections 6(b) and 6(e) of the Purchase Agreement and such other
               similar matters as such Person may reasonably request;

                    (2) an opinion, dated the date of effectiveness of the
               Registration Statement, of counsel for the Company covering
               matters similar to those set forth in Schedules D and E of the
               Purchase Agreement and such other matters as the Selling Holders
               may reasonably request, and in any event including a statement to
               the effect that such counsel has participated in conferences with
               officers and other representatives of the Company,
               representatives of the independent public accountants for the
               Company and have considered the matters required to be stated
               therein and the statements contained therein, although such
               counsel has not independently verified the accuracy, completeness
               or fairness of such statements; and that such counsel advises
               that, on the basis of the foregoing (relying as to materiality to
               the extent such counsel deems appropriate upon the statements of
               officers and other representatives of the Company) and without
               independent check or verification), no facts came to such
               counsel's attention that caused such counsel to believe that the
               applicable Registration Statement, at the time such Registration
               Statement or any post-effective amendment thereto became
               effective, contained an untrue statement of a material fact or
               omitted to state a

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               material fact required to be stated therein or necessary to make
               the statements therein not misleading, or that the Prospectus
               contained in such Registration Statement as of its date contained
               an untrue statement of a material fact or omitted to state a
               material fact necessary in order to make the statements therein,
               in the light of the circumstances under which they were made, not
               misleading. Without limiting the foregoing, such counsel may
               state further that such counsel assumes no responsibility for,
               and has not independently verified, the accuracy, completeness or
               fairness of the financial statements, notes and schedules and
               other financial data included in any Registration Statement
               contemplated by this Agreement or the related Prospectus; and

                    (3) a customary comfort letter, dated the date of
               effectiveness of the Registration Statement, from the Company's
               independent accountants, in the customary form and covering
               matters of the type customarily covered in comfort letters to
               underwriters in connection with underwritten offerings, and
               affirming the matters set forth in the comfort letters delivered
               pursuant to Section 9(i) of the Purchase Agreement; provided the
               appropriate representation letters are provided to the
               accountants from the Holders under Statement on Auditing
               Standards No. 72.

               (B)  set forth in full or incorporate by reference in the
          underwriting agreement, if any, in connection with any sale or resale
          pursuant to any Registration Statement the indemnification provisions
          and procedure of Section 8 hereof with respect to all parties to be
          indemnified pursuant to said Section; and

               (C)  deliver such other documents and certificates as may be
          reasonably requested by the Selling Holders to evidence compliance
          with the matters covered in clause (A) above and with any customary
          conditions contained in any agreement entered into by the Company
          pursuant to this clause;

          The above shall be done at each closing under such underwriting or
similar agreement, as and to the extent required thereunder, and if at any time
the representations and warranties of the Company contemplated in (A)(i) above
cease to be true and correct, the Company shall so advise the underwriter(s), if
any, and Selling Holders promptly and if requested by such Persons, shall
confirm such advise in writing.

               (xii)   prior to any public offering of Transfer Restricted
     Securities, cooperate with the Selling Holders, the underwriter(s), if any,
     and their respective counsel in connection with the registration and
     qualification of the Transfer Restricted Securities under the securities or
     Blue Sky laws of such jurisdictions as the Holders or underwriter(s), if
     any, may request and do any and all other acts or things necessary or
     advisable to enable the disposition in such jurisdictions of the Transfer
     Restricted Securities covered by the applicable Registration Statement;
     provided, however, that where Transfer Restricted Securities are offered
     other than through an underwritten offering, the Company agrees to cause
     its counsel to perform Blue Sky investigations and file registrations and
     qualifications required to be filed pursuant to this Section 5(a)(xiii),
     keep each such registration or qualification (or exemption therefrom)
     effective during the period that the applicable Registration Statement is
     required to remain effective under the terms of this Agreement and do any
     and all other acts or things necessary or advisable to enable the
     disposition in such jurisdictions of the securities covered thereby;
     provided that the Company shall not be required to register or qualify as a
     foreign corporation where it is not now so qualified or to take any action
     that would subject it to the service of process in suits or to taxation,
     other

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     than as to matters and transactions relating to the Registration Statement,
     in any jurisdiction where it is not now so subject;

               (xiii) in connection with any sale of Transfer Restricted
     Securities that will result in such securities no longer being Transfer
     Restricted Securities, cooperate with the Holders to facilitate the timely
     preparation and delivery of certificates representing Transfer Restricted
     Securities to be sold and not bearing any restrictive legends; and to
     register such Transfer Restricted Securities in such denominations and such
     names as the selling Holders may reasonably request at least two Business
     Days prior to such sale of Transfer Restricted Securities;

               (xiv)  use its reasonable best efforts to cause the disposition
     of the Transfer Restricted Securities covered by the Registration Statement
     to be registered with or approved by such other governmental agencies or
     authorities as may be necessary to enable the seller or sellers thereof to
     consummate the disposition of such Transfer Restricted Securities, subject
     to the proviso contained in clause (xii) above;

               (xv)   provide a CUSIP number for all Transfer Restricted
     Securities not later than the effective date of a Registration Statement
     covering such Transfer Restricted Securities and provide the Warrant Agent
     with printed certificates for the Transfer Restricted Securities which are
     in a form eligible for deposit with The Depository Trust Company;

               (xvi)  otherwise use its reasonable best efforts to comply with
     all applicable rules and regulations of the Commission, and make generally
     available to its security holders with regard to any applicable
     Registration Statement, as soon as practicable, a consolidated earnings
     statement meeting the requirements of Rule 158 (which need not be audited)
     covering a twelve-month period beginning after the effective date of the
     Registration Statement (as such term is defined in Rule 158(c) under the
     Act); and

               (xvii) provide promptly to the Holders, upon written request,
     each document filed with the Commission pursuant to the requirements of
     Section 13 or Section 15(d) of the Exchange Act.

     (b)  Restrictions on Holders. Each Holder agrees by acquisition of a
Transfer Restricted Security and the Initial Purchasers agrees that, upon
receipt of the notice (without notice of the nature or details of the events)
from the Company of the commencement of a Black Out Period (in each case, a
"Black Out Notice"), such Person will forthwith discontinue disposition of
Transfer Restricted Securities pursuant to the applicable Registration Statement
until such Person is advised in writing by the Company of the termination of the
Black Out Period and such Holder receives copies of the supplemented or amended
Prospectus contemplated by Section 5(a)(v) hereof, or until such Holder is
advised in writing by the Company that the use of the Prospectus may be resumed,
and has received copies of any additional or supplemental filings that are
incorporated by reference in the Prospectus. If so directed by the Company each
Person receiving a Black Out Notice hereby agrees that it will either (i)
destroy any Prospectuses, other than permanent file copies, then in such
Person's possession which have been replaced by the Company with more recently
dated Prospectuses or (ii) deliver to the Company (at the Company's expense) all
copies, other than permanent file copies, then in such Person's possession of
the Prospectus covering such Transfer Restricted Securities that was current at
the time of receipt of the Black Out Notice.

6. LIQUIDATED DAMAGES

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          If the Registration Statement: (i) is not filed with the Commission on
or prior to the date specified for such filing in Section 3(a) hereof; (ii) has
not been declared effective by the Commission on or prior to the dated specified
for such effectiveness in Section 3(a) hereof; or (iii) following the date such
Registration Statement is declared effective by the Commission, shall cease to
be effective without being restored to effectiveness by amendment or otherwise
within 30 business days, other than as permitted by Section 3(c) hereof (each
such event referred to in clauses (i) through (iii), a "Registration Default")
to the extent permitted by applicable law, the Company shall pay as liquidated
damages and not as a penalty to each Holder during the first 90-day period
immediately following the occurrence, and during the continuance of such
Registration Default, an amount equal to $0.01 per week per Warrant (or per such
number of Warrant Shares then issuable upon exercise of or in respect of a
Warrant) held by such Holder for each week or portion thereof that the
Registration Default continues. To the extent permitted by applicable law, the
amount of the liquidated damages will increase by an additional $0.01 per week
per Warrant (or per such number of Warrant Shares then issuable upon exercise of
or in respect of a Warrant) with respect to each subsequent 90-day period until
all Registration Defaults have been cured, up to a maximum amount of liquidated
damages of $0.05 per week per Warrant (or per such number of Warrant Shares then
issuable upon exercise of or in respect of a Warrant).

          All accrued liquidated damages shall be paid to record Holders by the
Company by wire transfer of immediately available funds, or by mailing a federal
funds check, on February 1 and August 1 of any given year. All obligations of
the Company set forth in the preceding paragraph that are outstanding with
respect to any Transfer Restricted Security at the time such security has been
effectively registered under the Act shall survive until such time as all such
obligations with respect to such security have been satisfied in full.

7. REGISTRATION EXPENSES

     All expenses incident to the Company's performance of or compliance with
this Agreement will be borne by the Company, regardless of whether a
Registration Statement becomes effective, including, without limitation: (i) all
registration and filing fees and expenses; (ii) all fees and expenses of
compliance with federal securities and state Blue Sky or securities laws; (iii)
all expenses of printing (including printing Prospectuses (whether for sales,
market-making or otherwise), messenger and delivery services and telephone; (iv)
all fees and disbursements of counsel for the Company; (v) all application and
filing fees in connection with listing the Warrant Shares on a national
securities exchange or automated quotation system pursuant to the requirements
hereof; and (vi) all fees and disbursements of independent certified public
accountants of the Company (including the expenses of any special audit (which
shall not be required except to the extent required by applicable law) and
comfort letters required by or incident to such performance).

     The Company will, in any event, bear its internal expenses (including,
without limitation, all salaries and expenses of its officers and employees
performing legal or accounting duties), the expenses of any annual audit and the
fees and expenses of any Person, including special experts, retained by the
Company.

8. INDEMNIFICATION

     (a)  The Company agrees to indemnify and hold harmless each Holder, its
directors, officers and each Person, if any, who controls such Holder (within
the meaning of Section 15 of the Act or Section 20 of the Exchange Act), from
and against any and all losses, claims, damages, liabilities, judgments,
(including, without limitation, any legal or other expenses incurred in
connection with investigating or defending any matter, including any action that
could give rise to any such losses, claims,

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damages, liabilities or judgments) caused by any untrue statement or alleged
untrue statement of a material fact contained in any Registration Statement,
preliminary prospectus or Prospectus (or any amendment or supplement thereto)
provided by the Company to any Holder or any prospective purchaser of Transfer
Restricted Securities, or caused by any omission or alleged omission to state
therein a material fact required to be stated therein or necessary to make the
statements therein not misleading, except insofar as such losses, claims,
damages, liabilities or judgments are caused by an untrue statement or omission
or alleged untrue statement or omission that is based upon information relating
to a Holder furnished in writing to the Company by such Holder.

     (b)  Each Holder of Transfer Restricted Securities agrees, severally and
not jointly, to indemnify and hold harmless the Company, its directors and
officers, and each person, if any, who controls (within the meaning of Section
15 of the Act or Section 20 of the Exchange Act) the Company, to the same extent
as the foregoing indemnity from the Company set forth in Section 6(a) hereof,
but only with reference to information relating to such Holder furnished in
writing to the Company by such Holder expressly for use in any Registration
Statement. In no event shall any Holder, its directors, officers or any Person
who controls such Holder be liable or responsible for any amount in excess of
the amount by which the total amount received by such Holder with respect to its
sale of Transfer Restricted Securities pursuant to a Registration Statement
exceeds (i) the amount paid by such Holder for such Transfer Restricted
Securities and (ii) the amount of any damages that such Holder, its directors,
officers or any Person who controls such Holder has otherwise been required to
pay by reason of such untrue or alleged untrue statement or omission or alleged
omission. This indemnity agreement shall be in addition to any liability which
any such Holder may otherwise have.

     (c)  In case any action shall be commenced involving any person in respect
of which indemnity may be sought pursuant to Section 8(a) or 8(b) (the
"indemnified party"), the indemnified party shall promptly notify the person
against whom such indemnity may be sought (the "indemnifying party") in writing,
and the indemnifying party shall assume the defense of such action, including
the employment of counsel reasonably satisfactory to the indemnified party and
the payment of all fees and expenses of such counsel, as incurred (except that,
in the case of any action in respect of which indemnity may be sought pursuant
to both Sections 8(a) and 8(b), a Holder shall not be required to assume the
defense of such action pursuant to this Section 8(c), but may employ separate
counsel and participate in the defense thereof, but the fees and expenses of
such counsel, except as provided below, shall be at the expense of the Holder).
Any indemnified party shall have the right to employ separate counsel in any
such action and participate in the defense thereof, but the fees and expenses of
such counsel shall be at the expense of the indemnified party, unless (i) the
employment of such counsel shall have been specifically authorized in writing by
the indemnifying party, (ii) the indemnifying party shall have failed to assume
the defense of such action or employ counsel reasonably satisfactory to the
indemnified party or (iii) the named parties to any such action (including any
impleaded parties) include both the indemnified party and the indemnifying
party, and the indemnified party shall have been advised by such counsel that
there may be one or more legal defenses available to it which are different from
or additional to those available to the indemnifying party (in which case the
indemnifying party shall not have the right to assume the defense of such action
on behalf of the indemnified party). In any such case, the indemnifying party
shall not, in connection with any one action or separate but substantially
similar or related actions in the same jurisdiction arising out of the same
general allegations or circumstances, be liable for the reasonable fees and
expenses of more than one separate firm of attorneys (in addition to any local
counsel) for all indemnified parties and all such reasonable fees and expenses
shall be reimbursed as they are incurred. Such firm shall be designated in
writing by a majority of the Holders, in the case of the parties indemnified
pursuant to Section 8(a), and by the Company, in the case of parties indemnified
pursuant to Section 8(b). The indemnifying party shall indemnify and hold
harmless the indemnified party from and against any and all losses, claims,
damages, liabilities and judgments by reason of any settlement of any action
effected with its written consent. The Company shall not, without the prior
written consent of the

                                       10

<PAGE>

indemnified party, effect any settlement or compromise of, or consent to the
entry of judgment with respect to, any pending or threatened action in respect
of which the indemnified party is or could have been a party and indemnity or
contribution may be or could have been sought hereunder by the indemnified
party, unless such settlement, compromise or judgment (i) includes an
unconditional release of the indemnified party from all liability on claims that
are or could have been the subject matter of such action and (ii) does not
include a statement as to or an admission of fault, culpability or a failure to
act, by or on behalf of the indemnified party.

     (d)  To the extent that the indemnification provided for in this Section 8
is unavailable to an indemnified party in respect of any losses, claims,
damages, liabilities or judgments referred to therein, then each indemnifying
party, in lieu of indemnifying such indemnified party, shall contribute to the
amount paid or payable by such indemnified party as a result of such losses,
claims, damages, liabilities or judgments (i) in such proportion as is
appropriate to reflect the relative benefits received by the Company, on the one
hand, and the Holders, on the other hand, from their sale of Transfer Restricted
Securities or (ii) if the allocation provided by clause 8(d)(i) is not permitted
by applicable law, in such proportion as is appropriate to reflect not only the
relative benefits referred to in clause 8(d)(i) hereof but also the relative
fault of the Company, on the one hand, and of the Holder, on the other hand, in
connection with the statements or omissions which resulted in such losses,
claims, damages, liabilities or judgments, as well as any other relevant
equitable considerations. The relative fault of the Company, on the one hand,
and of the Holder, on the other hand, shall be determined by reference to, among
other things, whether the untrue or alleged untrue statement of a material fact
or the omission or alleged omission to state a material fact relates to
information supplied by the Company, on the one hand, or by the Holder, on the
other hand, and the parties' relative intent, knowledge, access to information
and opportunity to correct or prevent such statement or omission. The amount
paid or payable by an indemnified party as a result of the losses, claims,
damages, liabilities or judgments referred to above shall be deemed to include,
subject to the limitations set forth in the second paragraph of Section 8(a),
any reasonable legal or other fees or expenses reasonably incurred by such
indemnified party in connection with investigating or defending any matter,
including any action that could have given rise to such losses, claims, damages,
liabilities or judgments.

     The Company and each Holder agree that it would not be just and equitable
if contribution pursuant to this Section 8(d) were determined by pro rata
allocation (even if the Holders were treated as one entity for such purpose) or
by any other method of allocation which does not take account of the equitable
considerations referred to in the immediately preceding paragraph.
Notwithstanding the provisions of this Section 8, no Holder, its directors, its
officers or any Person, if any, who controls such Holder shall be required to
contribute, in the aggregate, any amount in excess of the amount by which the
total received by such Holder with respect to the sale of Transfer Restricted
Securities pursuant to a Registration Statement exceeds (i) the amount paid by
such Holder for such Transfer Restricted Securities and (ii) the amount of any
damages which such Holder has otherwise been required to pay by reason of such
untrue or alleged untrue statement or omission or alleged omission. No person
guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of
the Act) shall be entitled to contribution from any person who was not guilty of
such fraudulent misrepresentation. The Holders' obligations to contribute
pursuant to this Section 8(d) are several in proportion to the respective
principal amount of Transfer Restricted Securities held by each Holder hereunder
and not joint.

9. RULE 144

     The Company agrees with each Holder, for so long as any Transfer Restricted
Securities remain outstanding and during any period in which the Company is
subject to Section 13 or 15(d) of the Exchange Act, to make all filings required
thereby in a timely manner in order to permit resales of such Transfer
Restricted Securities pursuant to Rule 144.

                                       11

<PAGE>

10. MISCELLANEOUS

     (a)  Remedies. The Company acknowledges and agrees that any failure by the
Company to comply with its obligations under this Agreement may result in
material irreparable injury to the Initial Purchasers or the Holders for which
there is no adequate remedy at law, that it will not be possible to measure
damages for such injuries precisely and that, in the event of any such failure,
the Initial Purchasers or any Holder may obtain such relief as may be required
to specifically enforce the Company's obligations under Section 3 hereof. The
Company further agrees to waive the defense in any action for specific
performance that a remedy at law would be adequate.

     (b)  No Inconsistent Agreements. The Company will not, on or after the date
of this Agreement, enter into any agreement with respect to its securities that
is inconsistent with the rights granted to the Holders in this Agreement or
otherwise conflicts with the provisions hereof. The rights granted to the
Holders hereunder do not in any way conflict with and are not inconsistent with
the rights granted to the holders of the Company's securities under any
agreement in effect on the date hereof, except that the filing of the
Registration Statement hereunder would require notice to be sent to holders
under the Company's registration rights agreement dated February 25, 1999, as
amended, and require the inclusion of such holders in a Registration Statement
filed hereunder.

     (c)  Amendments and Waivers. The provisions of this Agreement may not be
amended, modified or supplemented, and waivers or consents to or departures from
the provisions hereof may not be given unless (i) in the case of this Section
10(c)(i), the Company has obtained the written consent of Holders of all
outstanding Transfer Restricted Securities, and (ii) in the case of all other
provisions hereof, the Company has obtained the written consent of Holders of a
majority of the outstanding principal amount of Transfer Restricted Securities
(excluding Transfer Restricted Securities held by the Company or its
Affiliates).

     (d)  Third Party Beneficiary. The Holders shall be third party
beneficiaries to the agreements granting rights to Holders made hereunder
between the Company, on the one hand, and the Initial Purchasers, on the other
hand, and shall have the right to enforce such agreements directly to the extent
they may deem such enforcement necessary or advisable to protect its rights or
the rights of Holders hereunder.

     (e)  Notices. All notices and other communications provided for or
permitted hereunder shall be made in writing by hand-delivery, first-class mail
(registered or certified, return receipt requested), telex, telecopier, or air
courier guaranteeing overnight delivery:

               (i)     if to a Holder, at the address set forth on the records
     of the Warrant Agent, with a copy to the Warrant Agent; and

               (ii)    if to the Company:

                    American Tower Corporation
                    116 Huntington Avenue, 11/th/ Floor
                    Boston, MA 02116
                    Telecopier No.: (617) 375-7575
                    Attention: Chief Financial Officer and Treasurer
                               Executive Vice President and General Counsel

                                       12

<PAGE>

                    With a copy to:

                    Palmer & Dodge LLP
                    111 Huntington Avenue
                    Boston, MA 02199
                    Telecopier No.: (617) 227-4420
                    Attention: Matthew J. Gardella, Esq.

     All such notices and communications shall be deemed to have been duly
given: at the time delivered by hand, if personally delivered; five Business
Days after being deposited in the mail, postage prepaid, if mailed; when receipt
acknowledged, if telecopied; and on the next Business Day, if timely delivered
to an air courier guaranteeing overnight delivery.

     Copies of all such notices, demands or other communications shall be
concurrently delivered by the Person giving the same to the Warrant Agent at the
address specified in Warrant Agreement.

     (f)  Successors and Assigns. This Agreement shall inure to the benefit of
and be binding upon the successors and assigns of each of the parties,
including, without limitation, and without the need for an express assignment,
subsequent Holders; provided that nothing herein shall be deemed to permit any
assignment, transfer or other disposition of Transfer Restricted Securities in
violation of the terms hereof or of the Purchase Agreement or the Warrant
Agreement. If any transferee of any Holder shall acquire Transfer Restricted
Securities in any manner, whether by operation of law or otherwise, such
Transfer Restricted Securities shall be held subject to all of the terms of this
Agreement, and by taking and holding such Transfer Restricted Securities such
Person shall be conclusively deemed to have agreed to be bound by and to perform
all of the terms and provisions of this Agreement, including the restrictions on
resale set forth in this Agreement and, if applicable, the Purchase Agreement,
and such Person shall be entitled to receive the benefits hereof.

     (g)  Termination. This Agreement shall automatically terminate on the
Redemption Date if the Escrow Corp. Merger has not been consummated.

     (h)  Counterparts. This Agreement may be executed in any number of
counterparts and by the parties hereto in separate counterparts, each of which
when so executed shall be deemed to be an original and all of which taken
together shall constitute one and the same agreement.

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

     (j)  Governing Law. THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO THE
CONFLICT OF LAW RULES THEREOF. The Company hereby irrevocably and
unconditionally: (i) submits itself and its property in any legal action or
proceeding relating to this Agreement or for recognition and enforcement of any
judgment in respect thereof, to the non-exclusive jurisdiction of the courts of
the State of New York and the courts of the United States of America for the
Southern District of New York, and appellate courts thereof, and consents and
agrees to such action or proceeding being brought in such courts; and (ii)
waives any objection that it may now or hereafter have to the venue of any such
action or proceeding in any such court or that such action or proceeding was
brought in any inconvenient court and agrees not to plead or claim the same.

                                       13

<PAGE>

     (k)  Severability. In the event that any one or more of the provisions
contained herein, or the application thereof in any circumstance, is held
invalid, illegal or unenforceable, the validity, legality and enforceability of
any such provision in every other respect and of the remaining provisions
contained herein shall not be affected or impaired thereby.

     (l)  Entire Agreement. This Agreement is intended by the parties as a final
expression of their agreement and intended to be a complete and exclusive
statement of the agreement and understanding of the parties hereto in respect of
the subject matter contained herein. There are no promises, warranties or
undertakings, other than those set forth or referred to herein, with respect to
the registration rights granted with respect to the Transfer Restricted
Securities. This Agreement supersedes all prior agreements and understandings
between the parties with respect to such subject matter.

                                       14

<PAGE>

     IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
first written above.

                                AMERICAN TOWER CORPORATION

                                By: /s/ Bradley E. Singer
                                    --------------------------------------------
                                    Name:  Bradley E. Singer
                                    Title: Chief Financial Officer and Treasurer

The foregoing Agreement is hereby
  confirmed and accepted
  as of the date first above written.

By Credit Suisse First Boston LLC

By: /s/ Kristin M. Allen
    -----------------------------------
    Name: Kristin Allen
    Title: Managing Director

For themselves and the other several
Purchasers name in Schedule A to the Purchase Agreement.

<PAGE>

                                     ANNEX A

                           AMERICAN TOWER CORPORATION

                  Notice of Registration Statement and Selling
                          Securityholder Questionnaire
                                     (Date)

Reference is hereby made to the Warrant Registration Rights Agreement (the "
Warrant Registration Rights Agreement") between American Tower Corporation (the
"Company") and the Initial Purchasers named therein. Pursuant to the Warrant
Registration Rights Agreement, the Company has filed with the United States
Securities and Exchange Commission (the "Commission") a registration statement
on Form ___ (the "Shelf Registration Statement") for the registration and resale
under Rule 415 of the Securities Act of 1933, as amended (the "Securities Act"),
of the Company's warrants to purchase Class A Common Stock, par value $0.01 per
share of the Company, and the shares of Class A common stock issuable upon
exercise thereof (collectively, the "Securities"). All capitalized terms not
otherwise defined herein shall have the meanings ascribed thereto in the Warrant
Registration Rights Agreement.

Each beneficial owner of Transfer Restricted Securities (as defined below) is
entitled to have the Transfer Restricted Securities beneficially owned by it
included in the Shelf Registration Statement. In order to have Transfer
Restricted Securities included in the Shelf Registration Statement, this Notice
of Registration Statement and Selling Securityholder Questionnaire ("Notice and
Questionnaire") must be completed, executed and delivered to the Company's
counsel of the address set forth herein for receipt ON OR BEFORE [DEADLINE FOR
RESPONSE]. Beneficial owners of Transfer Restricted Securities who do not
complete, execute and return this Notice and Questionnaire by such date (i) will
not be named as selling securityholders in the Shelf Registration Statement and
(ii) may not use the Prospectus forming a part thereof for resales of Transfer
Restricted Securities.

Certain legal consequences arise from being named as a selling securityholder in
the Shelf Registration Statement and related Prospectus. Accordingly, holders
and beneficial owners of Transfer Restricted Securities are advised to consult
their own securities law counsel regarding the consequence of being named or not
being named as a selling securityholder in the Shelf Registration Statement and
related Prospectus.

The term "TRANSFER RESTRICTED SECURITIES" has the meaning assigned in the
Warrant Registration Rights Agreement.

<PAGE>

                                    ELECTION

The undersigned holder (the "Selling Securityholder") of Transfer Restricted
Securities hereby elects to include in the Shelf Registration Statement the
Transfer Restricted Securities beneficially owned by it and listed below in Item
(3). The undersigned, by signing and returning this Notice and Questionnaire,
agrees to be bound with respect to such Transfer Restricted Securities by the
terms and conditions of this Notice and Questionnaire and the Warrant
Registration Rights Agreement, as if the undersigned Selling Securityholder were
an original party thereto.

Upon any sale of Transfer Restricted Securities pursuant to the Shelf
Registration Statement, the Selling Securityholder will be required to deliver
to the Company and Trustee the Notice of Transfer set forth as Annex B to the
Warrant Registration Rights Agreement. The Selling Securityholder hereby
provides the following information to the Company and represents and warrants
that such information is accurate and complete:

                                        2

<PAGE>

                                  QUESTIONNAIRE

(1)  (a)  Full Legal Name of Selling Securityho1der:

     (b)  Full Legal Name of Holder (if not the same as in (a) above) of
          Transfer Restricted Securities Listed in Item (3) below:

     (c)  Full Legal Name of DTC Participant (if applicable and if not the same
          as (b) above) Through Which Transfer Restricted Securities Listed in
          Item (3) below are Held:

(2)  Address for Notices to Selling Securityholder:

     Telephone:
     Fax:
     Contact Person:

(3)  Beneficial Ownership of Securities:

     Except as set forth below in this Item (3), the undersigned does not
beneficially own any Securities.

     (a)  Number of Transfer Restricted Securities beneficially owned: _____
          CUSIP No(s). of such Transfer Restricted Securities_____

     (b)  Number of Securities other than Transfer Restricted Securities
          beneficially owned: ____ CUSIP No(s). of such other Securities_____

     (c)  Number of Transfer Restricted Securities which the undersigned wishes
          to be included in the Shelf Registration Statement: _____ CUSIP No(s).
          of such Transfer Restricted Securities to be included in the Shelf
          Registration Statement_____

(4)  Beneficial Ownership of other Securities of the Company:

     Except as set forth below in this Item (4), the undersigned Selling
     Securityholder is not the beneficial or registered owner of any other
     securities of the Company, other than the Securities listed above in Item
     (3).

     State any exceptions here:

(5)  Relationships with the Company:

     Except as set forth below, neither the Selling Securityholder nor any of
     its affiliates, officers, directors or principal equity holders (5% or
     more) has held any position or office or has had any other material
     relationship with the Company (or its predecessors or affiliates) during
     the past three years.

(6)  Plan of Distribution:

     State any exceptions here:

     Except as set forth below, the undersigned Selling Securityholder intends
to distribute the Transfer Restricted Securities listed above in Item (3) only
as follows (if at all): Such Transfer Restricted Securities may be sold from
time to time directly by the undersigned Selling Securityholder or,
alternatively, through underwriters, broker-dealers or agents. Such Transfer
Restricted Securities may be sold in one or more transactions at fixed prices,
at prevailing market prices at the time of sale, at varying prices determined at
the time of sale, or at negotiated prices. Such sales may be effected in
transactions (which may involve crosses or block transactions) (i) on any
national securities exchange or quotation

                                        3

<PAGE>

service on which the Registered Securities may be listed or quoted at the time
of sale, (ii) in the over-the-counter market, (iii) in transactions otherwise
than on such exchanges or services or in the over-the-counter market, or (iv)
through the writing of options. In connection with sales of the Transfer
Restricted Securities or otherwise, the Selling Securityholder may enter into
hedging transactions with broker-dealers, which may in turn engage in short
sales of the Transfer Restricted Securities in the course of hedging the
positions they assume. The Selling Securityholder may also sell Transfer
Restricted Securities short and deliver Transfer Restricted Securities to close
out such short positions, or loan or pledge Transfer Restricted Securities to
broker-dealers that in turn may sell such securities

     State any exceptions here:

By signing below, the Selling Securityholder acknowledges that it understands
its obligation to comply, and agrees that it will comply, with the provisions of
the Exchange Act and the rules and regulations thereunder, particularly
Regulation M.

In the event that the Selling Securityholder transfers all or any portion of the
Transfer Restricted Securities listed in Item (3) above after the date on which
such information is provided to the Company, the Selling Securityholder agrees
to notify the transferee(s) at the time of the transfer of its rights and
obligations under this Notice and Questionnaire and the Warrant Registration
Rights Agreement.

By signing below, the Selling Securityholder consents to the disclosure of the
information contained herein in its answers to Items (1) through (6) above and
the inclusion of such information in the Shelf Registration Statement and
related Prospectus. The Selling Securityholder understands that such information
will be relied upon by the Company in connection with the preparation of the
Shelf Registration Statement and related Prospectus. In accordance with the
Selling Securityholder's obligation under Section 3(e) of the Warrant
Registration Rights Agreement to provide such information as may be required by
law for inclusion in the Shelf Registration Statement, the Selling
Securityholder agrees to promptly notify the Company of any inaccuracies or
changes in the information provided herein which may occur subsequent to the
date hereof at any time while the Shelf Registration Statement remains in
effect. All notices hereunder and pursuant to the Warrant Registration Rights
Agreement shall be made in writing, by hand-delivery, or air courier
guaranteeing overnight delivery as follows:

(i)  To the Company:

     ___________________
     ___________________
     ___________________
     ___________________
     ___________________

(ii) With a copy to:

     ___________________
     ___________________
     ___________________

Once this Notice and Questionnaire is executed by the Selling Securityholder and
received by the Company's counsel, the terms of this Notice and Questionnaire,
and the representations and warranties contained herein, shall be binding on,
shall inure to the benefit of and shall be enforceable by the respective
successors, heirs, personal representatives, and assigns of the Company and the
Selling Securityholder (with respect to the Transfer Restricted Securities
beneficially owned by such Selling

                                        4

<PAGE>

Securityholder and listed in Item (3) above). This Agreement shall be governed
in all respects by the laws of the State of New York.

                                        5

<PAGE>

IN WITNESS WHEREOF, the undersigned, by authority duly given, has caused this
Notice and Questionnaire to be executed and delivered either in person or by its
duly authorized agent.

Dated:

Selling Securityholder
(Print/type full legal name of beneficial owner of Transfer Restricted
Securities)

By:
Name:
Title:

PLEASE RETURN THE COMPLETED AND EXECUTED NOTICE AND QUESTIONNAIRE FOR RECEIPT ON
OR BEFORE [DEADLINE FOR RESPONSE] TO THE COMPANY'S COUNSEL AT:

___________________
___________________
___________________
___________________
___________________

<PAGE>

                                     ANNEX B

Notice of Transfer Pursuant to Registration Statement

America Towers Corporation
The Bank of New York
Trustee Services
5 Penn Plaza, 13/th/ Floor
New York, NY 10001

Attention: Trust Officer

Re: Warrants to purchase Class A Common Stock, par value $0.01 per share

Dear Sirs:

     Please be advised that ____________________has transferred ________________
of the above-referenced Warrants pursuant to an effective Registration Statement
on Form [ ] (File No. 333-   ) filed by the Company.

     We hereby certify that the prospectus delivery requirements, if any, of the
Securities Act of 1933, as amended, have been satisfied and that the above-named
beneficial owner of the Warrants is named as a "Selling Holder" in the
Prospectus dated [DATE] or in supplements thereto, and that the number of
Warrants transferred is the number listed in such Prospectus opposite such
owner's name.

Dated:

                                             Very truly yours,

                                             ________________________________
                                             (Name)
                                             By: (Authorized Signature)<PAGE>

                                                                   Exhibit 10.20

                                RAYTHEON COMPANY
                      CHANGE IN CONTROL SEVERANCE AGREEMENT

        Agreement by and between Raytheon Company, a Delaware corporation (the
"Company"), and ______________ ("Executive") dated as of ________________, 2002.

        The Board of Directors of Company believes it is in the best interests
of the Company and its stockholders to have the continued dedication of
Executive notwithstanding the possibility, threat or occurrence of a Change in
Control (as defined in Section 1.5); to diminish the inevitable distraction of
Executive due to personal uncertainties and risks created by a threatened or
pending Change in Control; and to provide Executive with compensation and
benefits arrangements upon a Change in Control which are competitive with those
offered by other corporations.

        Therefore, the Board of Directors has caused the Company to enter into
this Agreement, and the Company and Executive agree as follows:

1       DEFINITIONS

For purposes of this Agreement, the following terms have the following meanings.

1.1     "Affiliated Company" means an affiliated company as defined in Rule
12b-2 of the Securities Exchange Act of 1934, as amended (the "Exchange Act").

1.2     "Base Salary" means Executive's annual base salary paid or payable
(including any base salary which has been earned but deferred) to Executive by
the Company or an affiliated company immediately preceding the date of a Change
in Control.

1.3     "Board" means the Board of Directors of the Company.

1.4     "Cause" means Executive's:

        (i)     willful and continued failure to perform substantially
                Executive's duties with the Company or one of its affiliates as
                such duties are constituted as of a Change in Control after the
                Company delivers to Executive written demand for substantial
                performance specifically identifying the manner in which
                Executive has not substantially performed Executive's duties;

        (ii)    conviction for a felony; or

<PAGE>

        (iii)   willfully engaging in illegal conduct or gross misconduct which
                is materially and demonstrably injurious to the Company.

For purposes of this Section 1.4, no act or omission by Executive shall be
considered "willful" unless it is done or omitted in bad faith or without
reasonable belief that Executive's action or omission was in the best interests
of the Company. Any act or failure to act based upon (a) authority given
pursuant to a resolution duly adopted by the Board, (b) instructions of the
Chief Executive Officer or a senior officer of the Company, or (c) advice of
counsel for the Company shall be conclusively presumed to be done or omitted to
be done by Executive in good faith and in the best interests of the Company. For
purposes of subsections (i) and (iii) above, Executive shall not be deemed to be
terminated for Cause unless and until there shall have been delivered to
Executive a copy of a resolution duly adopted by the affirmative vote of not
less than three quarters of the entire membership of the Board at a meeting
called and held for such purpose (after reasonable notice is provided to
Executive and Executive is given an opportunity, together with counsel, to be
heard before the Board) finding that in the good faith opinion of the Board
Executive is guilty of the conduct described in subsection (i) or (iii) above
and specifying the particulars thereof in detail.

1.5     "Change in Control" of the Company shall be deemed to have occurred as
of the first day that any one or more of the following conditions shall have
been satisfied:

        (i)     Any individual, entity or group (within the meaning of Section
                13(d)(3) or 14(d)(2) of the Exchange Act) (a "Person"), other
                than those Persons in control of the Company as of the date
                hereof or a trustee or other fiduciary holding securities under
                an employee benefit plan of the Company or a corporation owned
                directly or indirectly by the stockholders of the Company in
                substantially the same proportions as their ownership of stock
                of the Company, become the beneficial owner (as defined in Rule
                13d-3 under the Exchange Act), directly or indirectly, of
                securities of the Company representing 25% or more of the
                combined voting power of the Company's then outstanding
                securities; or

        (ii)    A change in the Board such that individuals who as of the date
                hereof constitute the Board (the "Incumbent Board") cease for
                any reason to constitute at least a majority of the Board;
                provided, however, that any individual becoming a director
                subsequent to the date hereof whose election or nomination for
                election by the Company's stockholders was approved by a vote of
                at least a majority of the directors then comprising the
                Incumbent Board shall be considered as though such individual
                were a member of the Incumbent Board; or

                                        2

<PAGE>

        (iii)   The stockholders of the Company approve: (a) a plan of complete
                liquidation of the Company; (b) an agreement for the sale or
                disposition of all or substantially all of the Company's assets;
                (c) a merger, consolidation or reorganization of the Company
                with or involving any other corporation, other than a merger,
                consolidation or reorganization that would result in the voting
                securities of the Company outstanding immediately prior thereto
                continuing to represent (either by remaining outstanding or by
                being converted into voting securities of the surviving entity)
                at least 50% of the combined voting power of the voting
                securities of the Company (or such surviving entity) outstanding
                immediately after such merger, consolidation or reorganization.

However, in no event shall a Change in Control be deemed to have occurred for
purposes of this Agreement if Executive is included in a Person that consummates
the Change in Control. Executive shall not be deemed to be included in a Person
by reason of ownership of (i) less than 3% of the equity in the Person or (ii)
an equity interest in the Person which is otherwise not significant as
determined prior to the Change of Control by a majority of the non-employee
continuing directors of the Company.

1.6     "Code" means the Internal Revenue Code of 1986, as amended.

1.7     "Good Reason" means any of the following acts or omissions by the
Company without Executive's express written consent:

        (i)     assigning to Executive duties materially inconsistent with
                Executive's position (including status, offices, titles and
                reporting requirements), authority or responsibilities
                immediately prior to a Change in Control or any other action by
                the Company which results in a material diminution of
                Executive's position, authority, duties or responsibilities as
                constituted immediately prior to a Change in Control;

        (ii)    requiring Executive (a) to be based at any office or location in
                excess of 50 miles from Executive's office or location
                immediately prior to a Change in Control or (b) to travel on
                Company business to a substantially greater extent than required
                immediately prior to a Change in Control;

        (iii)   reducing Executive's Base Salary;

        (iv)    materially reducing in the aggregate Executive's incentive
                opportunities under the Company's or an affiliated company's
                short- and long-term

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<PAGE>

                incentive programs as such opportunities exist immediately prior
                to a Change in Control;

        (v)     materially reducing Executive's targeted annualized award
                opportunities and/or the degree of probability of attainment of
                such annualized award opportunities as such opportunities exist
                immediately prior to a Change in Control;

        (vi)    failing to maintain Executive's amount of benefits under or
                relative level of participation in the Company's or an
                affiliated Company's employee benefit or retirement plans,
                policies, practices or arrangements in which the Executive
                participates immediately prior to a Change in Control;

        (vii)   purportedly terminating Executive's employment otherwise than as
                expressly permitted by this Agreement; or

        (viii)  failing to comply with and satisfy Section 8.3 hereof by
                requiring any successor to the Company to assume and agree to
                perform the Company's obligations hereunder.

1.8     "Qualifying Termination" means the occurrence of any of the following
events within twenty-four (24) calendar months after a Change in Control:

        (i)     the Company terminates the employment of Executive for any
                reason other than for Cause including, without limitation,
                forcing Executive to retire on any date not of Executive's
                choosing;

        (ii)    Executive terminates employment with the Company for Good
                Reason;

        (iii)   the Company fails to require a successor to assume, or a
                successor refuses to assume, the Company's obligations as
                required by Section 8 hereof; or

        (iv)    the Company or any successor breaches any of the provisions
                hereof.

1.9     "Severance Benefits" means:

        (i)     an amount equal to the product of Executive's Base Salary
                multiplied by two (2);

        (ii)    an amount equal to Executive's unpaid Base Salary through a
                Qualifying Termination;

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<PAGE>

        (iii)   an amount equal to the product of the greater of (a) Executive's
                annual bonus earned for the fiscal year immediately prior to a
                Change in Control and (b) Executive's target annual bonus
                established for the plan year in which a Qualifying Termination
                occurs multiplied by two (2);

        (iv)    an amount equal to the product of Executive's unpaid targeted
                annual bonus established for the plan year in which a Change in
                Control occurs multiplied by a fraction the numerator of which
                is the number of days elapsed in the current fiscal year to the
                Qualifying Termination and the denominator of which is 365;

        (v)     an amount equal to the dollar value of Executive's accrued
                vacation through a Qualifying Termination;

        (vi)    an amount equal to all compensation deferred by Executive
                together with all interest thereon;

        (vii)   an amount equal to the actuarial present value of the aggregate
                benefits accrued by Executive as of a Qualifying Termination
                under the Company's supplemental retirement plan calculated
                assuming that Executive's employment continued for two years
                following a Qualifying Termination; provided, however, that for
                purposes of determining Executive's final average pay under the
                supplemental retirement plan, Executive's actual pay history as
                of the Qualifying Termination shall be used; and

        (viii)  fringe benefits pursuant to all welfare, benefit and retirement
                plans under which Executive and Executive's family are eligible
                to receive benefits or coverage as of a Change in Control,
                including but not limited to life insurance, hospitalization,
                disability, medical, dental, pension and thrift plans.

2       QUALIFYING TERMINATION

2.1     Severance Benefits. Following a Qualifying Termination Executive shall
be entitled to all Severance Benefits, conditioned upon receipt of a written
release by the Executive of any claims against the Company or its subsidiaries,
except those claims arising under this Agreement or any other written plan or
agreement, which shall be specifically noted in such release.

2.2     Payment of Benefits. The Severance Benefits described in Sections 1.9
(i) through 1.9(vii) shall be paid in cash within 30 days of a Qualifying
Termination.

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<PAGE>

2.3     Duration of Benefits. The Severance Benefits described in Section
1.9(viii) shall be provided to Executive at the same premium cost as in effect
immediately prior to the Qualifying Termination. The welfare Severance Benefits
described in Section 1.9(viii) shall be provided following the Qualifying
Termination until the earlier of (i) the second anniversary of the Qualifying
Termination or (ii) the date Executive receives substantially equivalent welfare
benefits from a subsequent employer.

3       NON-QUALIFYING TERMINATIONS

3.1     Voluntary; for Cause; Death. Following a Change in Control, if
Executive's employment is terminated (i) voluntarily by Executive without Good
Reason, (ii) involuntarily by the Company for Cause or (iii) due to death,
Executive shall be entitled to Base Salary and benefits accrued through the date
of termination and Executive's entitlement to all other benefits shall be
determined in accordance with the Company's retirement, insurance and other
applicable plans, policies, practices and arrangements. Thereafter, the Company
shall have no further obligations to Executive hereunder.

4       NOTICE OF TERMINATION

4.1     Notice by Executive or Company. Any termination by Executive for Good
Reason or by the Company for Cause shall be communicated by written notice given
to the other in accordance with Section 9.2 hereof and which:

        (i)     indicates the specific termination provision in this Agreement
                relied upon;

        (ii)    sets forth in reasonable detail the facts and circumstances
                claimed to provide a basis for termination under the provision
                indicated to the extent possible; and

        (iii)   specifies the termination date (which date shall not be more
                than 30 days after the giving of such notice).

4.2     Failure to Give Notice. The failure by Executive or the Company to set
forth in the notice of termination required by Section 4.1 any fact or
circumstance which contributes to a showing of Good Reason or Cause shall not
waive any right of Executive or the Company, respectively, hereunder or preclude
Executive or the Company, respectively, from asserting such fact or circumstance
in enforcing Executive's or the Company's rights hereunder.

                                        6

<PAGE>

5       TAX PAYMENTS

5.1     Excise Tax Payments. (i) Anything in this Agreement to the contrary
notwithstanding and except as set forth below, if it is determined that any
payment or distribution by the Company to or for the benefit of Executive
(whether paid or payable or distributed or distributable pursuant to the terms
of this Agreement or otherwise, but determined without regard to any additional
payments required under this Section 5) (a "Payment") would be subject to the
excise tax imposed by Section 4999 of the Code, or any interest or penalties are
incurred by Executive with respect to such excise tax (such excise tax, together
with any such interest and penalties, are hereinafter collectively referred to
as the "Excise Tax"), then Executive shall be entitled to receive an additional
payment (a "Gross-Up Payment") in an amount such that after payment by Executive
of all taxes (including any interest or penalties imposed with respect to such
taxes), including, without limitation, any income taxes (and any interest and
penalties imposed with respect thereto) and Excise Tax imposed upon the Gross-Up
Payment, Executive retains an amount of the Gross-Up Payment equal to the Excise
Tax imposed upon the Payments. Notwithstanding the foregoing provisions of this
Subsection 5(i), if it is determined that Executive is entitled to a Gross-Up
Payment, but that Executive, after taking into account the Payments and the
Gross-Up Payment, would not receive a net after-tax benefit of at least $50,000
(taking into account both income taxes and any Excise Tax) as compared to the
net after-tax proceeds to Executive resulting from an elimination of the
Gross-Up Payment and a reduction of the Payments, in the aggregate, to an amount
(the "Reduced Amount") such that the receipt of Payments would not give rise to
any Excise Tax, then no Gross-Up Payment shall be made to Executive and the
Payments, in the aggregate, shall be reduced to the Reduced Amount.

(ii)    Subject to the provisions of Subsection 5(iii), all determinations
required to be made under this Section 5, including whether and when a Gross-Up
Payment is required and the amount of such Gross-Up Payment and the assumptions
to be utilized in arriving at such determination, shall be made by
PricewaterhouseCoopers or such other certified public accounting firm as may be
designated by Executive (the "Accounting Firm") which shall provide detailed
supporting calculations both to the Company and Executive within 15 business
days of the receipt of notice from Executive that there has been a Payment, or
such earlier time as is requested by the Company. If the Accounting Firm is
serving as accountant or auditor for the individual, entity or group effecting
the Change in Control, Executive shall appoint another nationally recognized
accounting firm to make the determinations required hereunder (which accounting
firm shall then be referred to as the Accounting Firm hereunder). All fees and
expenses of the Accounting Firm shall be borne solely by the Company. Any
Gross-Up Payment, as determined pursuant to this Section 5, shall be paid by the
Company to Executive within five days of the receipt of the Accounting Firm's
determination. Any determination by the Accounting Firm shall be binding upon
the Company and Executive. As a result of the uncertainty in the

                                        7

<PAGE>

application of Section 4999 of the Code at the time of the initial determination
by the Accounting Firm hereunder, it is possible that Gross-Up Payments which
will not have been made by the Company should have been made ("Underpayment"),
consistent with the calculations required to be made hereunder. If the Company
exhausts its remedies pursuant to Subsection 5(iii) and Executive thereafter is
required to make a payment of any Excise Tax, the Accounting Firm shall
determine the amount of the Underpayment that has occurred and any such
Underpayment shall be promptly paid by the Company to or for the benefit of
Executive.

(iii)   Executive shall notify the Company in writing of any claim by the
Internal Revenue Service that, if successful, would require the payment by the
Company of the Gross-Up Payment. Such notification shall be given as soon as
practicable but no later than ten business days after Executive is informed in
writing of such claim and shall apprise the Company of the nature of such claim
and the date on which such claim is requested to be paid. Executive shall not
pay such claim prior to the expiration of the 30-day period following the date
on which it gives such notice to the Company (or such shorter period ending on
the date that any payment of taxes with respect to such claim is due). If the
Company notifies Executive in writing prior to the expiration of such period
that it desires to contest such claim, Executive shall:

        (a)     give the Company any information reasonable requested by the
                Company relating to such claim,

        (b)     take such action in connection with contesting such claim as the
                Company shall reasonably request in writing from time to time,
                including, without limitation, accepting legal representation
                with respect to such claim by an attorney reasonably selected by
                the Company,

        (c)     cooperate with the Company in good faith in order effectively to
                contest such claim, and

        (d)     permit the Company to participate in any proceedings relating to
                such claim;

provided, however, that the Company shall bear and pay directly all costs and
expenses (including additional interest and penalties) incurred in connection
with such contest and shall indemnify and hold Executive harmless, on an
after-tax basis, for any Excise Tax or income tax (including interest and
penalties with respect thereto) imposed as a result of such representation and
payment of costs and expenses. Without limitation on the foregoing provisions of
this Subsection 5(iii), the Company shall control all proceedings taken in
connection with such contest and, at its sole option, may pursue or forgo any
and all administrative appeals, proceedings, hearings and conferences with the
taxing

                                        8

<PAGE>

authority in respect of such claim and may, at its sole option, either direct
Executive to pay the tax claimed and sue for a refund or to contest the claim in
any permissible manner, and Executive agrees to prosecute such contest to a
determination before any administrative tribunal, in a court of initial
jurisdiction and in one or more appellate courts, as the Company shall
determine; provided, however, that if the Company directs Executive to pay such
claim and sue for a refund, the Company shall advance the amount of such payment
to Executive, on an interest-free basis, and shall indemnify and hold Executive
harmless, on an after-tax basis, from any Excise Tax or income tax (including
interest or penalties with respect thereto) imposed with respect to such advance
or with respect to any imputed income with respect to such advance; and further
provided that any extension of the statute of limitations relating to payment of
taxes for the taxable year of Executive with respect to which such contested
amount is claimed to be due is limited solely to such contested amount.
Furthermore, the Company's control of the contest shall be limited to issues
with respect to which a Gross-Up Payment would be payable hereunder, and
Executive shall be entitled to settle or contest, as the case may be, any other
issue raised by the Internal Revenue Service or any other taxing authority.

(iv)    If, after the receipt by Executive of an amount advanced by the Company
pursuant to Subsection 5(iii), Executive becomes entitled to receive any refund
with respect to such claim, Executive shall (subject to the Company's complying
with the requirements of Subsection 5(iii) promptly pay to the Company the
amount of such refund (together with any interest paid or credited thereon after
taxes applicable thereto). If after the receipt by Executive of an amount
advanced by the Company pursuant to Subsection 5(iii), a determination is made
that Executive shall not be entitled to any refund with respect to such claim
and the Company does not notify Executive in writing of its intent to contest
such denial of refund prior to the expiration of 30 days after such
determination, then such advance shall be forgiven and shall not be required to
be repaid and the amount of such advance shall offset, to the extent thereof,
the amount of Gross-Up Payment required to be paid.

5.2     Tax Withholding. The Company may withhold from any amounts payable under
this Agreement such federal, state, local or foreign taxes as shall be required
to be withheld pursuant to any applicable law or regulation.

6       EXTENT OF COMPANY'S OBLIGATIONS

6.1     No Set-Off, Etc. The Company's obligation to make the payments and
perform it obligations hereunder shall not be affected by any set-off,
counterclaim, recoupment, defense or other claim, right or action which the
Company may have against Executive or others. All payments by the Company
hereunder shall be final, and the Company shall not seek to recover from
Executive any part of any payment for any reason whatsoever.

                                        9

<PAGE>

6.2     No Mitigation. In no event shall Executive be obligated to seek other
employment or take any other action by way of mitigation of the amounts payable
to Executive under any provision hereof, and such amounts shall not be reduced
whether or not Executive obtains other employment except to the extent
contemplated by Section 2.3 hereof.

6.3     Payment of Legal Fees and Costs. The Company agrees to pay as incurred,
to the full extent permitted by law, all legal fees and expenses which Executive
may reasonably incur as a result of any contest (regardless of the outcome
thereof) by the Company, Executive or others of the validity or enforceability
of, or liability under, any provision of this Agreement or any guarantee of
performance thereof (including as a result of any contest by Executive about the
amount of payment pursuant to this Agreement), plus in each case interest on any
delayed payment at the applicable federal rate provided for in Section
7872(f)(2)(A) of the Code.

6.4     Arbitration. Executive shall have the right to have settled by
arbitration any dispute or controversy arising in connection herewith. Such
arbitration shall be conducted in accordance with the rules of the American
Arbitration Association before a panel of three arbitrators sitting in a
location selected by Executive. Judgment may be entered on the award of the
arbitrators in any court having proper jurisdiction. All expenses of such
arbitration shall be borne by the Company in accordance with Section 6.3 hereof.

7       TERM

7.1     Initial Term. The term of this Agreement shall be two years from the
date hereof.

7.2     Renewal. The terms of this Agreement automatically shall be extended for
successive one-year terms unless canceled by the Company by written notice to
Executive not less than six months prior to the end of any term.

7.3     Effect of Change in Control. Notwithstanding Sections 7.1 and 7.2 to the
contrary, the Company may not cancel this Agreement following a Change in
Control.

8       SUCCESSORS

8.1     This Agreement is personal to Executive and without the prior written
consent of the Company shall not be assignable by Executive otherwise than by
will or the laws of descent and distribution. This Agreement shall be inure to
the benefit of and be enforceable by Executive's legal representatives.
Executive may from time to time designate in writing one or more persons or
entities as primary and/or contingent beneficiaries of any Severance Benefit
owing to Executive hereunder.

                                       10

<PAGE>

8.2     This Agreement shall inure to the benefit of and be binding upon the
Company and its successors and assigns.

8.3     The Company shall require any successor (whether direct or indirect by
purchase, merger, consolidation or otherwise) to all or substantially all of the
business and/or assets of the Company to assume expressly and agree to perform
this Agreement in the same manner and to the same extent that the Company would
be required to perform it if no such succession had taken place. For purposes
hereof, "Company" means the Company as hereinbefore defined and any successor to
its business and/or assets as aforesaid which assumes and agrees to perform this
Agreement by operation of law or otherwise.

9       MISCELLANEOUS

9.1     Heading. The headings are not part of the provisions hereof and shall
have no force or effect.

9.2     Notices. All notices and other communications hereunder shall be in
writing and shall be given by hand delivery or by registered or certified mail,
return receipt required, postage prepaid, addressed as follows:

        if to the Company:        Raytheon Company
                                  141 Spring Street
                                  Lexington, Massachusetts  02421
                                  Attention: General Counsel

        if to Executive:

or to such other address as either party shall have furnished to the other in
writing in accordance herewith. Notice and communications shall be effective
when actually received.

9.3     Severability. The invalidity or unenforceability of any provision of
this Agreement shall not affect the validity or enforceability of any other
provision hereof.

9.4     Compliance; Waiver. Executive's or the Company's failure to insist upon
strict compliance with any provision hereof or failure to assert any right
hereunder, including without limitation the right of Executive to terminate
employment for Good Reason pursuant to Section 2.1 hereof, shall not be deemed
to be a waiver of such provision or right or any other provision or right
hereof.

                                       11

<PAGE>

9.5     Employment Status. Executive and Company acknowledge that except as may
otherwise be provided under any other written agreement between Executive and
the Company, the employment of Executive by the Company is "at will" and prior
to a Change in Control may be terminated at any time by Executive or the
Company. Following a Change in Control, the provisions of this Agreement shall
supersede any other agreement between the parties with respect to the subject
matter hereof.

        IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first above written.

RAYTHEON COMPANY

By:
   ------------------------------------   --------------------------------------
   Keith J. Peden                            Executive
   Senior Vice President,
   Human Resources

                                       12

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