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                                                                     Exhibit 4.3

                                BAYER CORPORATION
                          EMPLOYEE SHARE PURCHASE PLAN


                                    ARTICLE I
                                     GENERAL

1.1      Purpose

         The Bayer Corporation Employee Share Purchase Plan (the "Plan") is
intended to encourage employee participation in the ownership and economic
progress of Bayer Aktiengesellschaft. The Plan is not intended to qualify under
Section 423 of the Internal Revenue Code of 1986, as amended.

1.2      Definitions

         Unless the context clearly indicates otherwise, the following terms
have the meanings set forth below:

         "ADS Purchase Agreement" shall mean the form or procedure prescribed by
the Corporation in order to participate in the Plan.

         "ADS Purchase Fund" shall have the meaning prescribed in Section 4.1.

         "ADSs" shall mean the sponsored American Depositary Shares of Bayer AG,
each of which represents one ordinary share of Bayer AG.

         "Affiliate" shall mean any entity controlling, controlled by or under
common control with the Corporation.

         "Bayer AG" shall mean Bayer Aktiengesellschaft.

         "Beneficiary" means the person(s) or estate entitled to receive a
Participant's Plan Account as a result of the death of that Participant.

         "Board" shall mean the Board of Directors of the Corporation.

         "Compensation" means, for all purposes of the Plan except as otherwise
specified, an Employee's base remuneration from the Corporation or a Designated
Participating Company received during a Purchase Period. For purposes of this
provision--

         (1)      Compensation shall include any overtime pay, commissions,
                  shift differentials, bilingual adjustments, and bonus
                  payments; provided, however, that any payments received under
                  the Productivity Plu$ Plan, or any similar plan, shall be
                  excluded.


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         (2)      Compensation shall include any Employee deferrals pursuant to
                  a cash or deferred arrangement under section 401(k) of the
                  Code and any amounts excluded from wages by reason of an
                  election to reduce wages in order to receive benefits under
                  section 125 of the Code.

         (3)      Compensation shall not include payments by reason of
                  termination of employment (such as severance pay), deferrals
                  or payments under any nonqualified deferred compensation
                  arrangement, payments under any long-term incentive
                  compensation program, special awards not specifically included
                  under paragraph (1), noncash compensation (such as any income
                  resulting from participation in this Plan), reimbursement of
                  expenses, foreign service premiums, tax equalization payments,
                  attendance and safety awards, or any other unearned income.

         "Corporation" shall mean Bayer Corporation.

         "Custodial Account" shall mean an account established pursuant to the
Custodial Agreement to hold the ADSs and other assets attributable to Plan
Accounts.

         "Custodial Agreement" shall mean an agreement between the Corporation
and the Custodian.

         "Custodian" shall mean the entity or entities designated from time to
time in a Custodial Agreement to hold assets attributable to Plan Accounts.

         "Designated Participating Company" shall mean any Affiliate that has
(i) been designated by the Corporation to participate under the Plan and (ii)
adopted the Plan for the benefit of its employees.

         "Disability" shall mean the Employee's receipt of long term disability
benefits under a disability plan sponsored by the Corporation or any Designated
Participating Company.

         "Employee" means any person who is employed by the Corporation or a
Designated Participating Company and scheduled to work at least twenty (20)
hours per week. For purposes of eligibility to participate in the Plan, the term
"Employee" shall include an individual covered by a collective bargaining
agreement between employee representatives and the Corporation or a Designated
Participating Company unless the collective bargaining agreement or the
collective bargaining agent expressly prohibits participation in the Plan. The
term "Employee" shall also not include an individual transferred to an entity
that is not a Designated Participating Company or classified by the Corporation
or a Designated Participating Company as a casual, seasonal, co-op or temporary
employee, student intern, work-study student or contract or independent contract
employee.


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         "Fair Market Value" of an ADS will be the closing trading price on the
trading day immediately preceding the Purchase Date or such other reasonable
method of determining fair market value as the Corporation may adopt from time
to time.

         "Notice of Withdrawal" shall mean the form or procedure prescribed by
the Corporation in order to voluntarily withdraw from the Plan.

         "Participant" shall mean any Employee who elects to participate.

         "Plan" shall mean this Bayer Corporation Employee Share Purchase Plan,
as the same may be amended from time to time.

         "Plan Account" shall mean an account established and maintained under
the Plan in the name of each Participant.

         "Plan Year" shall mean the twelve-month period beginning on January 1
and ending on the following December 31.

         "Purchase Date" shall mean the first business day of each month.

         "Purchase Period" shall mean each period beginning on the first day of
a month and ending on the last business day of that month.

         "Purchase Price" shall mean the purchase price of an ADS as provided in
Section 3.1 hereof.

         "Retirement" shall mean the cessation of an Employee's employment with
the Corporation and all Designated Participating Companies for any reason other
than the Employee's death after the Employee attains age 55 and completes ten or
more "Years of Vesting Service," as defined in and determined under the Bayer
Corporation Pension Plan.

1.3      Administration of Plan

         The Corporation shall administer the Plan and may delegate to any
management committee, employee, director or agent its responsibility to perform
any act hereunder, including without limitation those matters involving the
exercise of discretion, provided that such delegation shall be subject to
revocation at any time at its discretion. The Corporation shall have full
authority to determine all questions arising in connection with the Plan,
including interpreting its provisions and construing all of its terms, may adopt
procedural rules, and may employ and rely on such legal counsel, such actuaries,
such accountants and such agents as it may deem advisable to assist in the
administration of the Plan. All of its rules, interpretations and decisions
shall be applied in a uniform manner to all Participants similarly situated and
decisions of the Corporation shall be final, conclusive and binding on all
persons.



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1.4      Effective Date of Plan

         The Plan shall be effective on April 1, 2002.


                                   ARTICLE II
                                  PARTICIPATION

2.1      Eligibility

         Each Employee may elect to become a Participant effective as of the
next calendar quarter or as soon thereafter as is administratively possible by
delivering an ADS Purchase Agreement to the Corporation on or before the
fifteenth day of the month preceding the beginning of that calendar quarter.
Once an Employee elects to become a Participant, participation in the Plan will
continue for future pay periods at the same rate selected under Section 2.2
unless his or her participation is terminated in accordance with Article V or
changed in accordance with Article II.

2.2      Payroll Deductions

         Payment for shares of the ADSs purchased hereunder shall be made by
authorized payroll deductions in accordance with a Participant's ADS Purchase
Agreement. A Participant's payroll deduction amount must be expressed as a whole
percentage of not less than 1% and not more than 10% of such Participant's
Compensation; provided, however, that a Participant may not elect to deduct more
than ten thousand dollars ($10,000) in each Plan Year. A Participant may
increase or decrease his or her payroll deduction election for each quarter by
completing the procedures prescribed by the Corporation for such purpose on or
before the fifteenth day of the month preceding the beginning of that calendar
quarter. Payroll deduction amounts shall be credited to a Participant's Plan
Account.

2.3      Beneficiary Designation

         Upon commencing participation, each Participant shall designate a
Beneficiary on forms furnished by the Corporation. Such Participant may then
from time to time change his or her designated Beneficiary by written notice to
the Corporation and, upon such change, the rights of all previously designated
Beneficiaries to receive any benefits under this Plan shall cease. If, at the
date of death of the Participant, no duly designated Beneficiary exists, or if
the Beneficiary designated shall have died prior to the death of the
Participant, or if the Participant has revoked a prior designation by a writing
filed with the Corporation, without having filed a new designation, then any
death benefits which would have been payable to the Beneficiary shall be payable
to the Participant's spouse, if any, at the date of the Participant's death; if
no such spouse is then living, to the Participant's children, equally; or if
none survive, then to the Participant's estate.



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                                   ARTICLE III
                               PURCHASE OF SHARES

3.1      Purchase Price

         The Purchase Price per share of the ADSs purchased with Participants'
authorized payroll deductions shall be 85% of the Fair Market Value of such
share determined on the Purchase Date.

3.2      Purchase of Shares

         On each Purchase Date, the amount in a Participant's Plan Account shall
be charged with the aggregate Purchase Price of the number of whole and
fractional shares of ADSs that can be purchased with the amount. The Corporation
and each Designated Participating Company shall pay the fees and commissions, if
any, associated with the purchase of ADSs under the Plan.

3.3      Transferability of Rights

         Rights to purchase ADSs hereunder shall be exercisable only by the
Participant. Such rights shall not be transferable.

3.4      Adjustments of Securities

         Bayer AG may adjust the number and class of securities that may be
reserved for purchase, or be purchased, under the Plan in the event that (1)
adjustments are made in the number of outstanding ADSs and/or ordinary shares of
Bayer AG or (2) ADSs and/or ordinary shares of Bayer AG are exchanged for a
different class of securities of Bayer AG or for shares of stock of any other
corporation by reason of a merger, consolidation, stock dividend, stock split or
otherwise.

                                   ARTICLE IV
                                ADS PURCHASE FUND

4.1      ADS Purchase Fund

         The shares of ADSs purchased by Participants under the Plan and any
funds held by the Custodian (the "ADS Purchase Fund") shall be held by one or
more Custodians pursuant to the terms of an agreement between the Corporation
and such Custodian. Employees who authorize payroll deductions for participation
in the Plan will be deemed to have subscribed to the Custodial Agreement and to
have authorized the Custodian to hold and invest their contributions and other
additions to their accounts in accordance with the Plan and the Custodial
Agreement. No person shall have any right to or interest in the ADS Purchase
Fund except as provided in the Plan and Custodial Agreement. Participants'
payroll deductions shall be paid by the Corporation to the Custodian at regular
intervals and credited to Participants' individual accounts in accordance with
the certification of the Corporation, or its delegate, as to the names of the



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contributing Participants and the amounts contributed by each Participant. No
interest will be paid or credited on any amounts credited to Participants'
individual accounts.

         The ADS Purchase Fund shall be invested in ADSs. Except in the event of
a Participant's Retirement or upon termination of the Plan, dividends received
on ADSs and recovered tax withholdings on such dividends will be used to
purchase additional ADSs at a purchase price equal to the closing trading price
for ADSs on the first trading date after the dividend or tax refund is received
by the Custodian. In the event of a Participant's Retirement, dividends received
on ADSs and recovered tax withholdings on such dividends will be paid directly
to such Participant. The Custodian shall regularly purchase ADSs from time to
time in the open market in accordance with a non-discretionary purchasing
program. Cash balances (including any interim investment thereof) shall not be
maintained in the ADS Purchase Fund except to the extent that such balances are
in anticipation of cash distributions or are maintained in order not to disrupt
the nondiscretionary purchasing program of the Custodian required by the Plan.

         The share of each Participant in the ADS Purchase Fund shall be debited
to such Participants' Plan Account. As of each Purchase Date, the Custodian
shall revalue the fund (exclusive of contributions to be made as of such
Purchase Date) at then current market values and shall certify the value thereof
to the Corporation. As of each Purchase Date, the Corporation, or its delegate,
shall adjust each Plan Account for activity in the period elapsed since the last
preceding Purchase Date by adding together all income received and accrued,
realized and unrealized profits, and deducting therefrom all taxes, charges or
expenses and any realized or unrealized losses which may have been sustained.
The Corporation, or its delegate or delegates, as the case may be, shall
apportion the fund as revalued as of each Purchase Date among the Participants
in proportion to their respective interests in the fund immediately preceding
such Purchase Date. As soon as practicable after the close of each calendar
quarter, or at such more frequent intervals as may be determined by the
Corporation, there shall be sent to each Participant a written statement of the
amount to the credit of his Plan Account as of the last Purchase Date in such
period.

                                    ARTICLE V
                          TERMINATION OF PARTICIPATION

5.1      Voluntary Withdrawal

         A Participant may withdraw from the Plan at any time by filing a Notice
of Withdrawal with the Corporation to be effective as soon as administratively
practicable. Upon withdrawal, the entire cash balance, if any, allocable to that
Participant's Plan Account will be charged for the purchase of whole and
fractional shares of ADSs pursuant to Section 3.2 hereof on the next succeeding
Purchase Date. Any Participant who withdraws from the Plan may again become a
Participant in accordance with Section 2.1 hereof.


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5.2      Termination of Eligibility

         If a Participant ceases to be eligible under Section 2.1 hereof for any
reason including due to death, Disability, Retirement, cessation of employment
or unpaid leave of absence, the entire cash balance, if any, allocable to that
Participant's Plan Account will be charged for the purchase of whole and
fractional shares of ADSs pursuant to Section 3.2 hereof on the next succeeding
Purchase Date.

                                   ARTICLE VI
                WITHDRAWALS AND DISTRIBUTIONS FROM PLAN ACCOUNTS

6.1      Withdrawals and Distributions From Plan Accounts

         Subject to the terms and conditions set forth below, a Participant may,
at any time, sell or certificate and have delivered to him or her all or a part
of the ADSs recorded in such Participant's Plan Account by completing the
withdrawal process established for this purpose by the Corporation.

         Payment of withdrawal requests will be made in cash or American
Depositary Receipts representing ADSs, as requested by the Participant, and will
be made as soon as administratively practicable following the receipt by the
Corporation of the request. Any expenses relating to the sale or certification
will be borne by the Participant.

         Upon the termination of a Participant's eligibility to participate in
the Plan under Section 5.2 for any reason other than Disability, unpaid approved
leave of absence, Retirement or a change in employment status reducing a
Participant's hours to less than 20 hours per week, an American Depositary
Receipt representing the whole shares of ADSs reflected in that Participant's
Plan Account and a cash payment for the fractional shares of ADSs reflected in
that Participant's Plan Account will be mailed to the Participant after sixty
(60) days unless the Participant directs the sale of the ADSs prior to the
distribution. If the Participant's cessation of employment is based on the
Participant's Disability, unpaid approved leave of absence, Retirement or a
change in employment status reducing a Participant's hours to less than 20 hours
per week, then no distribution will be made until requested by the Participant.

6.2      Application for Distributions

         In order to receive a distribution under the Plan, a Participant or
Beneficiary, as the case may be, must make application therefor in accordance
with procedures prescribed by the Corporation. The Corporation may require that
there be furnished to it in connection with such application all information
pertinent to any question of eligibility and the amount of any distribution. The
Corporation may permit applications for distributions to be made through the
completion and filing of forms provided for this purpose and/or through
electronic, telephonic or computer means, or as otherwise determined by the
Corporation in its sole discretion.



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                                   ARTICLE VII
                          VOTING AND TENDERING OF ADSs

         Each Participant (or in the event of his death, his Beneficiary or
estate) shall have the right to instruct the Custodian as to the manner in which
to (1) exercise voting rights at each annual and each special meeting of the
stockholders of Bayer AG, and/or (2) respond to a voluntary tender or exchange
offer with respect to ADSs credited to such Participant's account under the
Plan. The Corporation shall utilize its best efforts to distribute on a timely
basis or cause to be distributed to each Participant (or Beneficiary or estate)
such information as will be distributed to holders of the ADSs in connection
with any such meeting or voluntary tender or exchange offer, together with an
appropriate form for the Participant to indicate his instructions. Upon its
receipt of such instructions, the Custodian shall cause the voting or tender of
such ADSs as and to the extent so instructed. It is the intent of this provision
of the Plan to treat all such Participants (or their Beneficiaries or their
estates) as if they held directly all ADSs to the credit of their account under
the Plan so that if a Participant (or Beneficiary or estate) does not instruct
the Custodian to vote, tender or exchange such ADSs at a stockholder meeting or
pursuant to the terms of any voluntary tender or exchange offer, the Custodian
shall conclude that such Participant does not wish to have his ADSs voted,
tendered or exchanged. The Custodian shall have no discretion in such matter and
shall take no action with respect to any such meeting, or voluntary tender or
exchange offer except to the extent it receives instructions from Participants.
The Custodian shall keep confidential all instructions it receives pursuant to
this Article VII, except the aggregate number of votes voting for or against or
abstaining with respect to a matter submitted to a stockholder vote.

                                  ARTICLE VIII
                   PLAN AMENDMENT, MODIFICATION OR SUSPENSION

         The Plan may be amended, modified or suspended in whole or in part, at
any time and from time to time by the Corporation; provided, however, that no
such amendment, modification or suspension (i) shall adversely affect in a
material manner any right of any Participant with respect to amounts credited to
such Participant's Plan Account prior to the effective date of such amendment,
modification or suspension or (ii) shall require Bayer AG's approval unless such
approval is given by Bayer AG.

                                   ARTICLE IX
                                   TERMINATION

         The Plan may be terminated at any time by appropriate action of the
Corporation and will automatically terminate on the Purchase Date on which an
insufficient number of ADSs remains available for purchase under the Plan. Upon
termination, Plan Accounts will continue to be held under the Plan until
withdrawn or distributed in accordance with the terms of the Plan.

                                    ARTICLE X
                               GENERAL PROVISIONS

10.1     Notices

         Any notice that a Participant files pursuant to the Plan shall be made
on forms prescribed by the Corporation and shall be effective when received by
the Corporation.



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10.2     Condition of Employment

         Neither the creation of the Plan nor participation therein shall be
deemed to create any right of continued employment or in any way affect the
right of the Corporation to terminate an Employee.

10.3     Withholding

         The Corporation or Designated Participating Employer will have the
right to withhold from any remuneration payable to a Participant any income or
employment taxes required to be withheld as a result of that Participant's
participation in the Plan.

10.4     Governing Law

         The validity, construction, interpretation, administration and effect
of the Plan, and of its rules and regulations, and rights relating to the Plan,
shall be governed by the substantive laws, but not the choice of law rules, of
the Commonwealth of Pennsylvania.


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