<PAGE>
                                                                     EXHIBIT 4.3

                       NAVIGATION TECHNOLOGIES CORPORATION

                             STOCK OPTION AGREEMENT

I.   NOTICE OF STOCK OPTION GRANT

     John MacLeod
     14 Portuguese Boulevard Road
     Rolling Hills, California 90274

     You have been granted an option (this "Option") to purchase shares of
Common Stock of the Company (each an "Option Share" and, collectively, the
"Option Shares"), subject to the terms and conditions of this Stock Option
Agreement dated as of September 18, 2000 (this "Option Agreement"), as follows:

     General Terms of this Option:

          Total Number of Option Shares           3,000,000

          Exercise Price per Option Share         $1.10

          Total Exercise Price                    $3,300,000

          Vesting Commencement Date               September 18, 2000

          Expiration Date:                        September 1, 2010

     Exercisability and Vesting:

     Notwithstanding anything herein to the contrary, this Option may be
exercised only to the extent it has become vested. Subject to the two
immediately succeeding paragraphs, this Option will vest and become exercisable
with respect to 1/48 of the Option Shares on October 1, 2000 and an additional
1/48 of the Option Shares on the first day of each month thereafter, subject to
your Continuous Status as an Employee on each such date.

     In the event of a Change of Control (as defined below), that portion of
this Option which has not yet vested as of the date of such Change of Control
will immediately vest and become

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exercisable simultaneously with the consummation of such Change of Control,
subject to your Continuous Status as an Employee until such Change of Control;
provided that, in the event your employment is terminated by the Company without
Cause (as defined in your Employment Agreement with the Company, dated as of
September 18, 2000 (your "Employment Agreement")) or you terminate your
employment with Good Reason (as defined in your Employment Agreement), in each
case at any time within the three month period immediately preceding such Change
of Control, then that portion of this Option which has not yet vested as of the
date of such Change of Control will still immediately vest and become
exercisable simultaneously with the consummation of such Change of Control. Any
portion of this Option which has not been exercised prior to or in connection
with a Change of Control will be forfeited.

     In the event that your employment is terminated by the Company without
Cause or is terminated by you with Good Reason, this Option will vest and become
exercisable with respect to an additional number of Option Shares equal to the
lesser of (i) 750,000 Option Shares (as adjusted for stock splits and
combinations) and (ii) that portion of this Option which had not yet vested as
of immediately prior to the termination of your Continuous Status as an
Employee.

     Except as otherwise provided herein, this Option, to the extent vested, may
be exercised in whole or in part at any time prior to the close of business on
the 90th day following the termination of your Continuous Status as an Employee.
Notwithstanding the foregoing, (i) in the event that you have voluntarily
terminated your employment without Good Reason, this Option, to the extent
vested, may be exercised in whole or in part at any time prior to the 60th day
following the termination of your Continuous Status as an Employee, (ii) in the
event of your death, this Option, to the extent vested, may be exercised in
whole or in part at any time during the 18 month period immediately following
your death, and (iii) in the event you have a Disability, this Option, to the
extent vested, may be exercised in whole or in part at any time during the 12
month period immediately following your Disability. Notwithstanding anything
herein to the contrary, in no event may all or any portion of this Option be
exercised later than the Expiration Date set forth above.

II.  DEFINITIONS

     As used herein, the following definitions shall apply:

     (a) "Board" means the Board of Directors of the Company.

     (b) "Change of Control" means the sale of the Company to an Independent
Third Party (as defined below) or affiliated group of Independent Third Parties
pursuant to which such party or parties acquire (i) capital stock of the Company
possessing the voting power under normal circumstances to elect a majority of
the Board (whether by merger, consolidation, sale or transfer of the Company's
capital stock) or (ii) all or substantially all of the Company's assets
determined on a consolidated basis.


                                      -2-
<PAGE>

     (c) "Code" means the Internal Revenue Code of 1986, as amended.

     (d) "Common Stock" means the Common Stock of the Company.

     (e) "Company" means Navigation Technologies Corporation, a Delaware
corporation.

     (f) "Continuous Status as an Employee" means that your employment with the
Company, or any Parent or Subsidiary of the Company, has not been interrupted or
terminated. Continuous Status as an Employee shall not be considered interrupted
in the case of (i) any leave of absence approved by the Company or (ii)
transfers between locations of the Company or between the Company, its Parent,
any Subsidiary, or any successor. A leave of absence approved by the Company
shall include sick leave, military leave, or any other personal leave approved
by an authorized representative of the Company.

     (g) "Disability" means total and permanent disability as defined in Section
22(e)(3) of the Code.

     (h) "Employee" means an individual who is employed by the Company or any
Parent or Subsidiary of the Company. Neither service as a director of the
Company or any Parent of Subsidiary of the Company nor payment of a director's
fee by any such entity shall be sufficient to classify such individual as an
"Employee."

     (i) "Fair Market Value" means, as of any date, the value of Common Stock
determined as follows:

          (a) If the Common Stock is listed on any established stock exchange or
a national market system (including, without limitation, the Nasdaq National
Market or The Nasdaq SmallCap Market of The Nasdaq Stock Market), its Fair
Market Value shall be the closing sales price for such stock (or the closing
bid, if no sales were reported) as quoted on such exchange or system for the
last market trading day prior to the time of determination, as reported in The
Wall Street Journal or such other source as the Board deems reliable;

          (b) If the Common Stock is regularly quoted by a recognized securities
dealer but selling prices are not reported, the Fair Market Value of a share of
Common Stock shall be the mean between the high bid and low asked prices for the
Common Stock on the last market trading day prior to the day of determination,
as reported in The Wall Street Journal or such other source as the Board deems
reliable;

          (c) In the absence of an established market for the Common Stock, the
Fair Market Value shall be determined in good faith by the Board.


                                      -3-
<PAGE>

     (j) "Independent Third Party" means any person or entity who, immediately
prior to the contemplated transaction, does not own in excess of 5% of the
Company's common stock on a fully-diluted basis, who is not controlling,
controlled by or under common control with any such 5% owner of the Company's
common stock and who is not the spouse or descendent (by birth or adoption) of
any such 5% owner of the Company's common stock.

     (k) "Notice of Grant" means the written notice above evidencing certain
terms and conditions of this Option. The Notice of Grant is part of this Option
Agreement.

     (l) "Parent" means a "parent corporation" (whether now or hereafter
existing) as defined in Section 424(e) of the Code.

     (m) "Subsidiary" means a "subsidiary corporation" (whether now or hereafter
existing) as defined in Section 424(f) of the Code.

III. AGREEMENT

     1. Grant of Option. The Company hereby grants to John MacLeod ("you" or
"Optionee") this Option to purchase the number of Option Shares set forth in the
Notice of Grant, at the Exercise Price Per Option Share set forth in the Notice
of Grant (the "Exercise Price"), subject to the terms and conditions of this
Option Agreement. This Option is not intended to qualify as an Incentive Stock
Option under section 422 of the Code.

     2. Exercise of Option.

          (a) Right to Exercise. This Option is exercisable prior to the
Expiration Date (as set forth in the Notice of Grant) in accordance with the
Exercisability and Vesting provisions set forth in the Notice of Grant and the
other applicable provisions of this Option Agreement. In the event of Optionee's
death, Disability or other termination of Optionee's employment, the
exercisability of this Option is governed by the applicable Exercisability and
Vesting provisions set forth in the Notice of Grant and this Option Agreement.

          (b) Method of Exercise. This Option is exercisable by delivery of an
exercise notice, in the form attached as Exhibit A (the "Exercise Notice"),
which shall state the election to exercise this Option, the number of Option
Shares in respect of which this Option is being exercised (the "Exercised
Shares"), and such other representations and agreements as may be required by
the Company. The Exercise Notice shall be signed by the Optionee and shall be
delivered in person or by certified mail to the Secretary of the Company. The
Exercise Notice shall be accompanied by payment of the aggregate Exercise Price
as to all Exercised Shares. This Option shall be deemed to be exercised upon
receipt by the Company of such fully executed Exercise Notice accompanied by
such aggregate Exercise Price.


                                      -4-
<PAGE>

     No Option Shares shall be issued pursuant to the exercise of this Option
unless such issuance and exercise complies with all relevant provisions of law
and the requirements of any stock exchange or quotation service upon which the
Company's Common Stock is then listed. Assuming such compliance, for income tax
purposes, the Exercised Shares shall be considered transferred to the Optionee
on the date this Option is exercised with respect to such Exercised Shares.

     3. Method of Payment. Payment of the aggregate Exercise Price shall be by
any of the following, or a combination thereof, at the election of the Optionee:

          (a) cash;

          (b) certified or cashiers check;

          (c) delivery of a properly executed notice together with such other
documentation as the Company and the broker, if applicable, shall require to
effect an exercise of this Option and delivery to the Company of the sale or
loan proceeds required to pay the exercise price; or

          (d) surrender of other shares of Common Stock of the Company which
have been owned by the Optionee for more than six (6) months on the date of
surrender and have a Fair Market Value on the date of surrender equal to the
aggregate Exercise Price of the Exercised Shares.

     4. Non-Transferability of Option. This Option may not be transferred in any
manner otherwise than by will or by the laws of descent or distribution or by
transfer to Optionee's spouse and/or descendants (whether natural or adopted) or
any entity in which you, your spouse and/or your descendants collectively own a
100% direct or indirect beneficial interest (collectively, "Permitted
Transferees"), provided that such Permitted Transferees have agreed in writing
to be bound by the provisions of this Option Agreement. This Option may be
exercised in accordance with the terms hereof during the lifetime of Optionee
only by the Optionee or Permitted Transferees. The terms of this Option
Agreement shall be binding upon the executors, administrators, heirs, successors
and assigns of both the Optionee and the Permitted Transferees.

     5. Term of this Option. This Option may not be exercised, in whole or in
part, after the Expiration Date set forth in the Notice of Grant.

     6. Lock-Up Period. Optionee hereby agrees that in connection with any
registration of the offering of any securities of the Company under the
Securities Act of 1933, as amended (the "Securities Act"), Optionee shall not
sell or otherwise transfer any Option Share during the 180-day period (or such
longer or shorter period as may be requested in writing by the Managing
Underwriter and agreed to in writing by the Company) (the "Market Standoff
Period") following the effective date of a registration statement of the Company
filed under the Securities Act. The


                                      -5-
<PAGE>

Company may impose stop-transfer instructions with respect to securities subject
to the foregoing restrictions until the end of such Market Standoff Period.

     7. Optionee's Representations. In the event the Option Shares have not been
registered under the Securities Act of 1933, as amended, at the time this Option
is exercised, the Optionee shall, if required by the Company, concurrently with
the exercise of all or any portion of this Option, deliver to the Company his or
her Investment Representation Statement in the form attached hereto as Exhibit
B.

     8. Restrictions on Exercise. This Option may not be exercised if the
issuance of any Option Share upon such exercise or the method of payment of
consideration for any such Option Share would constitute a violation of any
applicable law. Optionee represents that when he exercises this Option, he will
be purchasing Option Shares for his own account and not on behalf of others.
Optionee understands and acknowledges that federal and state securities laws
govern and restrict his right to offer, sell or otherwise dispose of Option
Shares issued upon exercise of this Option unless such offer, sale or other
disposition thereof is registered under the Securities Act and state securities
laws, or in the opinion of the Company's counsel, such offer, sale or other
disposition is exempt from registration or qualification thereunder. Optionee
agrees that he will not offer, sell or otherwise dispose of any Option Share in
any manner which would: (i) require the Company to file any registration
statement with the Securities and Exchange Commission (or any similar filing
under state law) or to amend or supplement any such filing or (ii) violate or
cause the Company to violate the Securities Act, the rules and regulations
promulgated thereunder or any state or other federal law, or (iii) violate any
agreement between Optionee and the Company, including this Option Agreement.
Optionee further understands that all certificates evidencing any Option Share
purchased hereunder will bear such legends as the Company deems necessary or
desirable in connection with the Securities Act or other rules, regulations or
laws.


                                      -6-
<PAGE>

     9. Withholding of Taxes. The Company shall be entitled, if necessary or
desirable, to withhold from you from any amounts due and payable by the Company
to you (or secure payment from you in lieu of withholding) the amount of any
withholding or other tax due from the Company with respect to any Option Share
issued pursuant to this Option Agreement, and the Company may defer such
issuance unless indemnified by you to its satisfaction.

     10. Adjustments. In the event of a reorganization, recapitalization, stock
dividend or stock split, or combination or other similar change in the shares of
Common Stock, the Board will, in order to prevent the dilution or enlargement of
rights under this Option, make such adjustments in the number and type of Option
Shares covered by this Option and the Exercise Price specified herein as may be
reasonably determined by the Board to be appropriate and equitable. The issuance
by the Company of shares of stock of any class, or options or securities
exercisable or convertible into shares of stock of any class, for cash or
property, or for labor or services either upon direct sale or upon the exercise
of rights or warrants to subscribe therefor, or upon exercise or conversion of
other securities, shall not affect, and no adjustment by reason thereof shall be
made with respect to, the number or price of Option Shares subject to this
Option.

     11. Entire Agreement; Governing Law. This Option Agreement (including,
without limitation, the Notice of Grant) constitutes the entire agreement of the
parties with respect to the subject matter hereof and supersedes in their
entirety all prior undertakings and agreements of the Company and Optionee with
respect to the subject matter hereof, and may not be modified adversely to the
Optionee's interest except by means of a writing signed by the Company and
Optionee. This Option Agreement is governed by the laws of the State of Delaware
except for that body of law pertaining to conflict of laws. Each party hereby
irrevocably consents to the exclusive jurisdiction of the federal and state
courts located in Chicago, Illinois with respect to any actions arising in
connection with this Option Agreement that are not required by Section 12 below
to be arbitrated.

     12. Arbitration. Except as otherwise provided in this Section 12, any
controversy or claim arising out of or relating to this Option Agreement, or the
breach thereof, shall be settled by arbitration administered by the American
Arbitration Association in accordance with its Commercial Arbitration Rules, and
judgment on the award rendered by the arbitrators may be entered in any court
having jurisdiction thereof.

     Within fifteen (15) days after the commencement of arbitration, the Company
and Optionee shall each select one person to act as arbitrator and the two
selected shall select a third arbitrator within ten (10) days of their
appointment. If the arbitrators so selected are unable or fail to agree upon the
third arbitrator, or if either party fails to appoint an arbitrator, such
arbitrator or arbitrators shall be selected by the American Arbitration
Association.

     Each of the parties to this Option Agreement acknowledges that a breach of
this Option Agreement may cause the other party irreparable harm which may not
be adequately compensated by money damages. Therefore, in the event of a breach
or threatened breach by either


                                      -7-
<PAGE>

the Company or Optionee, injunctive or other equitable relief will be available
to the other party, and any arbitrator acting pursuant to this Option Agreement
shall have the authority to provide such injunctive or other equitable relief.

     The arbitrators shall have the authority to award such remedies or relief
that a court of the State of Delaware could order or grant in an action governed
by Delaware law, including, without limitation, specific performance of any
obligation created under this Option Agreement, the issuance of an injunction or
the imposition of sanctions for abuse or frustration of the arbitration process.
The arbitration proceedings shall be conducted in Chicago, Illinois.

     Notwithstanding the foregoing, any party may bring and pursue an action in
any federal or state court located in Chicago, Illinois seeking provisional
relief, including a temporary restraining order or preliminary injunction,
pending an arbitration proceeding. Any provisional relief obtained shall be
discontinued once the arbitrators have assumed jurisdiction and ordered such
discontinuance.

     13. NO GUARANTEE OF EMPLOYMENT. OPTIONEE ACKNOWLEDGES AND AGREES THAT THE
VESTING OF OPTION SHARES PURSUANT TO THE VESTING PROVISIONS SET FORTH HEREIN IS
EARNED ONLY BY CONTINUING SERVICE AS AN EMPLOYEE AT THE WILL OF THE COMPANY (AND
NOT THROUGH THE ACT OF BEING HIRED, BEING GRANTED AN OPTION OR PURCHASING OPTION
SHARES HEREUNDER). OPTIONEE FURTHER ACKNOWLEDGES AND AGREES THAT THIS OPTION
AGREEMENT, THE TRANSACTIONS CONTEMPLATED HEREUNDER AND THE VESTING PROVISIONS
SET FORTH HEREIN DO NOT CONSTITUTE AN EXPRESS OR IMPLIED PROMISE OF CONTINUED
ENGAGEMENT AS AN EMPLOYEE OR CONSULTANT FOR THE VESTING PERIOD, FOR ANY PERIOD,
OR AT ALL, AND SHALL NOT INTERFERE WITH OPTIONEE'S RIGHT OR THE COMPANY'S RIGHT
TO TERMINATE OPTIONEE'S EMPLOYMENT AT ANY TIME, WITH OR WITHOUT CAUSE.

OPTIONEE HAS READ AND UNDERSTANDS SECTION 12, WHICH DISCUSSES ARBITRATION.
OPTIONEE UNDERSTANDS THAT BY SIGNING THIS OPTION AGREEMENT, OPTIONEE AGREES TO
SUBMIT ANY CLAIMS ARISING OUT OF, RELATING TO, OR IN CONNECTION WITH THIS OPTION
AGREEMENT TO BINDING ARBITRATION, AND THAT THIS ARBITRATION CLAUSE CONSTITUTES A
WAIVER OF OPTIONEE'S RIGHT TO A JURY TRIAL AND RELATES TO THE RESOLUTION OF ALL
DISPUTES RELATING TO ALL ASPECTS OF THIS RELATIONSHIP.

                                     * * * *


                                      -8-
<PAGE>
By your signature and the signature of the Company's representative below, you
and the Company hereby agree that this Option is granted under and governed by
the terms of this Option Agreement (including, without limitation, the Notice of
Grant). In addition, your signature below evidences your acknowledgment that you
have reviewed this Option Agreement in its entirety, have had an opportunity to
obtain the advice of counsel prior to executing this Option Agreement and fully
understand all provisions of this Option Agreement. You also agree to notify the
Company upon any change in the residence address indicated below.


OPTIONEE:                                    NAVIGATION TECHNOLOGIES
                                             CORPORATION


/s/ John K. MacLeod                          /s/ Judson Green
----------------------------------           -----------------------------
Signature                                    By


----------------------------------           -----------------------------------
Print Name                                   Name


----------------------------------           President & Chief Executive Officer
                                             -----------------------------------
                                             Title
----------------------------------
Residence Address


                                      -9-
<PAGE>

                                CONSENT OF SPOUSE

     The undersigned spouse of John MacLeod ("Optionee") has read and hereby
approves the terms and conditions of the foregoing Option Agreement dated as of
September 18, 2000 (the "Option Agreement") between the undersigned's spouse and
Navigation Technologies Corporation (the "Company"). In consideration of
granting the undersigned's spouse the right to purchase shares of the Company's
common stock as set forth in the Option Agreement, the undersigned hereby agrees
to be irrevocably bound by the terms and conditions of the Option Agreement and
further agrees that any community property interest shall be similarly bound.
The undersigned hereby appoints the undersigned's spouse as attorney-in-fact for
the undersigned with respect to any amendment or exercise of rights under the
Option Agreement.


/s/ Judith Goyette MacLeod
----------------------------------
Signature of Spouse of Optionee


----------------------------------
Print Name

<PAGE>

                                    EXHIBIT A


Navigation Technologies Corporation
10400 Higgins Road, Suite 400
Rosemont, Illinois 60018
Attention:  Secretary

                       NAVIGATION TECHNOLOGIES CORPORATION
                                 EXERCISE NOTICE

     1. Exercise of Option. Effective as of today, _________ __, 20__, the
undersigned ("Optionee") hereby elects to purchase _________ shares (the
"Shares") of the Common Stock of Navigation Technologies Corporation (the
"Company") under and pursuant to the Stock Option Agreement dated as of
September 18, 2000 (the "Option Agreement"). The aggregate purchase price for
the Shares shall be $__________, as required by the Option Agreement.

     2. Delivery of Payment. Optionee herewith delivers to the Company the
aggregate purchase price for the Shares.

     3. Representations of Optionee. Optionee acknowledges that Optionee has
received, read and understood the Option Agreement and agrees to abide by and be
bound by its terms and conditions.

     4. Rights as Shareholder. Until the stock certificate evidencing such
Shares is issued (as evidenced by the appropriate entry on the books of the
Company or of a duly authorized transfer agent of the Company), no right to vote
or receive dividends or any other rights as a shareholder shall exist with
respect to any Share, notwithstanding the exercise of this Option. A share
certificate for the number of Shares so acquired shall be issued to the Optionee
as soon as practicable after exercise of this Option.

     5. Tax Consultation. Optionee understands that Optionee may suffer adverse
tax consequences as a result of Optionee's purchase or disposition of the
Shares. Optionee represents that Optionee has consulted with any tax consultants
Optionee deems advisable in connection with the purchase or disposition of the
Shares and that Optionee is not relying on the Company for any tax advice.

     6. Entire Agreement; Governing Law. The Option Agreement is incorporated
herein by reference. This Agreement constitutes the entire agreement of the
parties and supersedes in their entirety all prior undertakings and agreements
of the Company and Optionee with respect to the subject matter hereof, and such
agreement is governed by the laws of the State of Delaware except for that body
of laws pertaining to conflict of laws. Should any provision of this Agreement
be

<PAGE>

determined by a court of law to be illegal or unenforceable, the other
provisions shall nevertheless remain effective and shall remain enforceable.


                       NAVIGATION TECHNOLOGIES CORPORATION
                           EXERCISE NOTICE (CONTINUED)

Submitted by:                                Accepted by:

OPTIONEE:                                    NAVIGATION TECHNOLOGIES
                                             CORPORATION

----------------------------                 --------------------------------
Signature                                    By

----------------------------                 --------------------------------
Print Name                                   Title

----------------------------                 --------------------------------
                                             Date Accepted
----------------------------
Address of Optionee



<PAGE>

                                    EXHIBIT B

                       INVESTMENT REPRESENTATION STATEMENT

OPTIONEE:

COMPANY:       NAVIGATION TECHNOLOGIES CORPORATION

SECURITY:      COMMON STOCK

AMOUNT:

DATE:

     In connection with the purchase of the above-listed Securities, the
undersigned Optionee represents to the Company the following:

     a. Optionee is aware of the Company's business affairs and financial
condition and has acquired sufficient information about the Company to reach an
informed and knowledgeable decision to acquire the Securities. Optionee is
acquiring these Securities for investment for Optionee's own account only and
not with a view to, or for resale in connection with, any "distribution" thereof
within the meaning of the Securities Act of 1933, as amended (the "Securities
Act").

     b. Optionee acknowledges and understands that the Securities constitute
"restricted securities" under the Securities Act and have not been registered
under the Securities Act in reliance upon a specific exemption therefrom, which
exemption depends upon, among other things, the bona fide nature of Optionee's
investment intent as expressed herein. In this connection, Optionee understands
that, in the view of the Securities and Exchange Commission, the statutory basis
for such exemption may be unavailable if Optionee's representation was
predicated solely upon a present intention to hold these Securities for the
minimum capital gains period specified under tax statutes, for a deferred sale,
for or until an increase or decrease in the market price of the Securities, or
for a period of one year or any other fixed period in the future. Optionee
further understands that the Securities must be held indefinitely unless they
are subsequently registered under the securities Act and that the Company is
under no obligation to register the Securities. Optionee understands that the
certificate evidencing the Securities will be imprinted with a legend which
prohibits the transfer of the Securities unless they are registered or such
registration is not required in the opinion of counsel satisfactory to the
Company, a legend prohibiting their transfer without the consent of the
Commissioner of Corporations of the State of California and any other legend
required under applicable state securities laws.

     c. Optionee is familiar with the provisions of Rule 701 and Rule 144, each
promulgated under the Securities Act, which in substance, permit limited public
resale of "restricted securities"

<PAGE>

acquired directly or indirectly from the issuer thereof in a non-public offering
subject to the satisfaction of certain conditions. Rule 701 provides that if the
issuer qualifies under rule 701 at the time of the grant of this Option to the
Optionee, the exercise will be exempt from registration under the Securities
Act. In the event the Company becomes subject to the reporting requirements of
Section 13 or 15(d) of the Securities Exchange Act of 1934, ninety (90) days
thereafter (or such longer period as any market stand-off agreement may require)
the Securities exempt under Rule 701 may be resold, subject to the satisfaction
of certain of the conditions specified by Rule 144, including: (1) the resale
being made through a broker in an unsolicited "broker's transaction" or in
transactions directly with a market maker (as said term is defined under the
Securities Exchange Act of 1934); and, in the case of an affiliate, (2) the
availability of certain public information about the Company, (3) the amount of
Securities being sold during any three month period not exceeding the
limitations specified in rule 144(e) and (4) the timely filing of a Form 144, if
applicable.

     In the event that the Company does not qualify under Rule 701 at the time
of grant of this Option, then the Securities may be resold in certain limited
circumstances subject to the provisions of rule 144, which requires the resale
to occur not less than one year after the later of the date the Securities were
sold by the Company or the date the Securities were sold by an affiliate of the
Company, within the meaning of rule 144; and, in the case of acquisition of the
Securities by an affiliate, or by a non-affiliate who subsequently holds the
Securities less than two years, the satisfaction of the conditions set forth in
sections (1), (2), (3) and (4) of the paragraph immediately above.

     d. Optionee further understands that in the event all of the applicable
requirements of Rule 701 or 144 are not satisfied, registration under the
Securities Act, compliance with Regulation A, or some other registration
exemption will be required; and that, notwithstanding the fact that Rules 144
and 701 are not exclusive, the Staff of the Securities and Exchange Commission
has expressed its opinion that persons proposing to sell private placement
securities other than in a registered offering or pursuant to Rules 144 or 701
will have a substantial burden of proof in establishing that an exemption from
registration is available for such offers or sales, and that such persons and
their respective brokers who participate in such transactions do so at their own
risk. Optionee understands that no assurances can be given that any such other
registration exemption will be available in such event.

                                           Signature of Optionee:


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

                                           Date:                         , 20
                                                ------------------   ----    ---