S-8

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As filed with the Securities and Exchange Commission on January 21, 2004, Registration No. 33-            

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM S-8

REGISTRATION STATEMENT UNDER THE
SECURITIES ACT OF 1933

AVENTIS
(Exact Name of registrant as specified in its charter)

The Republic of France (State or other jurisdiction of incorporation or organization)	None (IRS Employer Identification No.)
67917 Strasbourg cedex 9 France (Address of principal executive offices)

AVENTIS STOCK OPTION PLAN 2003
(Full title of the plan)

Edward H. Stratemeier, Esq.
Aventis Pharmaceuticals
300 Somerset Corporate Boulevard
Mail Code SC3-830A
Bridgewater, New Jersey 08807-2854
(Name and address of agent for service)

(908) 243-6000
(Telephone number, including area code, of agent for service)

CALCULATION OF REGISTRATION FEE

Title of securities to be registered	Amount to be registered	Proposed maximum offering price per share	Proposed maximum aggregate offering price	Amount of registration fee
American Depositary Shares, each representing one Ordinary Share, nominal value €3.82 per share, and an equal number of options to purchase such shares	6,500,000 shares	$56.92*	$369,980,000	$29,931.38

*

For the purpose of computing the registration fee, the offering price of Euro 47.52 per share was converted to U.S. Dollars at the interbank currency exchange rate at December 2, 2003, of $1.1978 per Euro.

PART I

INFORMATION REQUIRED IN THE PROSPECTUS

Item 1.    Plan Information

        Omitted pursuant to the instructions and provisions of Form S-8.

Item 2.    Registrant Information and Employee Plan Annual Information

        Omitted pursuant to the instructions and provisions of Form S-8.

PART II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.    Incorporation of Documents by Reference

        This Registration Statement on Form S-8 hereby incorporates by reference the contents of the following documents filed by Aventis (the "Registrant") with the Securities and Exchange Commission (the "Commission") pursuant to the Securities Exchange Act of 1934, as amended (the "Exchange Act"):

(a)

The Annual Report on Form 20-F of the Registrant for the year ended December 31, 2002 (Registration No. 1-18378) (the "Form 20-F") filed pursuant to Section 13(a) or 15(d) of the Exchange Act;



(b)

All other reports filed by the Registrant pursuant to Section 13(a) or 15(d) of the Exchange Act since December 31, 2002; and



(c)

(i) The description of the Registrant's Ordinary Shares contained in the Registration Statement on Form 8-A (Registration No. 1-18378) (the "Form 8-A") dated January 19, 1993, and (ii) the description of the Registrant's Ordinary Shares set forth under the heading "Description of Equity Capital Structure" contained in the Prospectus included in the Registration Statement on Form F-2 (Registration No. 33-54956), which description is incorporated by reference in the Form 8-A, as such description is amended and updated by the information set forth under the heading "Description of Share Capital" contained in the Prospectus dated October 22, 1997 included in the Registration Statement on Form F-3 (Registration No. 33-7730) and by the information set forth under the heading "Description of Aventis Share Capital" contained in the Prospectus dated October 26, 1999 included in the Registration Statement on Form F-4 (Registration No. 33-11008), including any amendment or report filed for the purpose of updating such description.

        All documents filed by the Registrant pursuant to Sections 13(a), 13(c), 14, or 15(d) of the Exchange Act, prior to the filing of a post-effective amendment indicating that all securities offered have been sold or that deregisters all securities then remaining unsold shall be deemed to be incorporated by reference in this Registration Statement and to be a part hereof from the date of filing of such documents so incorporated by reference. Statements contained in the foregoing documents incorporated by reference shall be deemed to be modified or superseded hereby to the extent that statements contained in the Prospectus, or in any subsequently filed documents that are amendments hereto or that are incorporated herein by reference, shall modify or replace such statements.

Item 4.    Description of Securities

        The information required by Item 4 is not applicable to this Registration Statement because the class of securities to be offered is registered under Section 12 of the Exchange Act.

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Item 5.    Interests of named Experts and Counsel

        The information required by Item 5 is not applicable to this Registration Statement.

Item 6.    Indemnification of Directors and Officers

        The Registrant indemnifies and maintains liability insurance on behalf of its Directors and Officers against liability they may incur as a result of claims for wrongful acts alleged to have occurred in their capacities as Directors and Officers of the Registrant, with certain exceptions, principally related to securities transactions, environmental pollution, violation of responsibilities related to employee benefit plans, infliction of bodily injury or damage or destruction of tangible property, and fraudulent acts and omissions.

Item 7.    Exemption from Registration Claimed

        The information required by Item 7 is not applicable to this Registration Statement.

Item 8.    Exhibits

Exhibit Number	Description
4.1	The Articles of Association of the Registrant
4.2	Rules and Regulations for Aventis Stock Option Plan 2003
4.3	Amended and Restated Deposit Agreement, dated as of December 15, 1994, among the Registrant (then named Rhône-Poulenc S.A.) and Citibank N.A., as Depositary, and holders from time to time of American Depositary Receipts issued thereunder, including the form of American Depositary Receipts
5	Opinion of Bruno Angrand, Head of Corporate Law Division, Corporate Legal Department of the Registrant, regarding the legality of the securities
23.1	Consent of PricewaterhouseCoopers to incorporation by reference of Independent Auditors' Report
23.2	Consent of Bruno Angrand, Head of Corporate Law Division, Corporate Legal Department of the Registrant
24	Power of Attorney

Item 9.    Undertakings

        The undersigned Registrant hereby undertakes:

(1)

To file, during any period in which offers or sales are being made, a post-effective amendment to this Registration Statement:



(i)

To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933, as amended (the "Securities Act");



(ii)

To reflect in the prospectus any facts or events arising after the effective date of the Registration Statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the Registration Statement;

3

(iii)

To include any material information with respect to the plan of distribution not previously disclosed in the Registration Statement or any material change to such information in the Registration Statement,

provided, however, that paragraphs (1)(i) and (1)(ii) do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in periodic reports filed with or furnished to the Commission by the Registrant pursuant to Section 13 or 15(d) of the Exchange Act that are incorporated by reference in the Registration Statement.

(2)

That, for the purpose of determining any liability under the Securities Act, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.



(3)

To remove from registration by means of a post-effective amendment any of the securities being registered that remain unsold at the termination of the offering.

        The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act, each filing of the Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the Exchange Act (and, where applicable, each filing of an employee benefit plan's annual report pursuant to Section 15(d) of the Exchange Act) that is incorporated by reference in the Registration Statement shall be deemed to be a new registration statement relating to the securities therein, and the offering of such securities at that time shall be deemed the initial bona fide offering thereof.

        Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers, and controlling persons of the Registrant pursuant to the provisions described in Item 6 of this Registration Statement, or otherwise, the registrant has been advised that in the opinion of the Commission such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Registrant of expenses incurred or paid by a director, officer, or controlling person of the Registrant in the successful defense of any action, suit, or proceeding) is asserted by such director, officer, or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

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SIGNATURES

        The Registrant.    Pursuant to the requirements of the Securities Act of 1933, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, as of January 21, 2004.

AVENTIS
By:	/s/  IGOR LANDAU Igor Landau Chairman of the Management Board

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POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that each of the undersigned hereby constitutes and appoints Richard J. Markham, Gerald P. Belle, Edward H. Stratemeier, and Owen K. Ball, Jr., or any of them (with full power to each of them to act alone), his true and lawful attorney-in-fact and agent, with full power of substitution, for him and on his behalf and in his name, place, and stead, in any and all capacities, to sign, execute, and file this Registration Statement under the Securities Act of 1933, as amended, and any or all amendments (including, without limitation, post-effective amendments), with all exhibits and any and all documents required to be filed with respect thereto, with the Securities and Exchange Commission or any regulatory authority, granting unto such attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary to be done in and about the premises in order to effectuate the same, as fully to all intents and purposes as he himself might or could do, if personally present, hereby ratifying and confirming all that said attorneys-in-fact and agents, or any of them, or their substitute or substitutes, may lawfully do or cause to be done.

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SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed by the following persons in the capacities indicated as of January 21, 2004.

Name of Signatory	Capacities in Which Signing
/s/  IGOR LANDAU Igor Landau	Chairman of the Management Board (Principal Executive Officer)
/s/  RICHARD J. MARKHAM Richard J. Markham	Vice Chairman of the Management Board and Chief Operating Officer
/s/  PATRICK LANGLOIS Patrick Langlois	Vice Chairman of the Management Board and Chief Financial Officer (Principal Financial Officer)
/s/  FRANK L. DOUGLAS Frank L. Douglas	Member of the Management Board and Executive Vice President for Drug Innovation and Approval
Heinz Werner Meier	Member of the Management Board and Executive Vice President for Human Resources
/s/  DIRK OLDENBURG Dirk Oldenburg	Member of the Management Board, Executive Vice President and General Counsel
/s/  THIERRY SOURSAC Thierry Soursac	Member of the Management Board and Executive Vice President for Commercial Operations
/s/  MICHEL FINANCE Michel Finance	Chief Accounting Officer (Principal Accounting Officer)
/s/  EDWARD H. STRATEMEIER Edward H. Stratemeier	Authorized Representative in the United States

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EXHIBIT INDEX

Regulation S-K Exhibit Number	Description of Document	Sequential Page Number
4.1	The Articles of Association of the Registrant (incorporated by reference from the Registration Statement on Form F-4 of the Registrant (then named Rhône-Poulenc S.A.) (Registration No. 333-11008) effective October 26, 1999)
4.2	Rules and Regulations for Aventis Stock Option Plan 2003	9
4.3	Amended and Restated Deposit Agreement, dated as of December 15, 1994, among the Registrant (then named Rhône-Poulenc S.A.) and Citibank N.A., as Depositary, and holders from time to time of American Depositary Receipts issued thereunder, including the form of American Depositary Receipts (incorporated by reference from the registration statement on Form F-3 of Rhône- Poulenc S.A. (Registration No. 333-7730) filed October 20, 1997)
5	Opinion of Bruno Angrand, Head of Corporate Law Division, Corporate Legal Department of the Registrant, regarding the legality of the securities offered under the Plan	17
23.1	Consent of PricewaterhouseCoopers to incorporation by reference of Independent Auditors' Report	18
23.2	Consent of Bruno Angrand, Head of Corporate Law Division, Corporate Legal Department of the Registrant (included in Exhibit 5)
24	Power of Attorney (included in signature page)

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PART I INFORMATION REQUIRED IN THE PROSPECTUS
PART II INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
SIGNATURES
POWER OF ATTORNEY
SIGNATURES
EXHIBIT INDEX

EX-4.2

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Exhibit 4.2

APPENDIX 1

RULES AND REGULATIONS
FOR THE AVENTIS STOCK
OPTION
PLAN 2003

Grant of December 2, 2003

I.     GENERAL PRINCIPLES AND PURPOSE FOR AVENTIS STOCK OPTION PLAN

        A stock option plan is a system that enables its beneficiaries to subscribe for new shares in their company (or in the parent company of their group) during a certain period, at a price fixed at the opening of the plan and that remains fixed during the whole of this period.

        The purpose of Aventis stock option plan 2003 is to foster and promote the long-term success of Aventis Group and increase shareholder value by motivating superior performance by means of performance-related incentives and by encouraging and providing for the acquisition of an ownership interest in Aventis Group by employees. The people concerned can therefore choose to be fully associated to the running of their company and benefit from capital gains if the share price progresses favourably.

        Stock option plans of Aventis are governed by the French law and notably by Articles L 225-177 to L 225-185 of the Commercial Law concerning business corporations.

        On the basis of the authorization and the powers which have been given to it by the Company's shareholders meeting, the Aventis Management Board has decided on the creation of the present Aventis stock option plan 2003 and has laid down the conditions within the framework of the legal provisions mentioned above. The Management Board can adapt these conditions, notably in the case of changes in the regulations relative to the stock options.

II.    DEFINITIONS

        Whenever used herein, the following terms shall have the respective meanings set forth below:

        "Aventis" means Aventis or the Company, as French holding company for an international group in the global life sciences industry.

        "Aventis Group" means the Company together with any company, partnership or other group of economic interest or legal entity where at least 10% of the capital or voting rights is held directly or indirectly by the Company, on the date of exercise.

        "Beneficiary" means any Employee of the Aventis Group designated by the Management Board to receive options.

        "Change in control," means exclusively the occurrence of any of the following events:

(a)

carrying out a takeover bid or a public offer of exchange.



(b)

the direct or indirect acquisition of an interest allowing a new shareholder to hold at least 20% of the voting rights in the shareholders' meeting, or to increase his/her previous interest so as to hold at least 20% of the voting rights in the shareholders' meeting.



(c)

the demerger, the contribution or transferral of significant corporate assets of the Company, which necessitate a shareholders' meeting of the Company.

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(d)

the direct or indirect intervention of a rival company in the management of the Company.



(e)

the merger-absorption by the Company of a rival company involving the arrival of shareholders holding over 20% of the voting rights of the company resulting from the merger, and the merger-absorption of the Company by a rival company involving the arrival of new shareholders holding over 20% of the voting rights of the company resulting from the merger.

        "Company" means Aventis, a French company, and any successor thereto.

        "Employee" means any employee of the Company or of Aventis Group.

        "Management Board" means the Management Board of directors of Aventis.

        "Option" means the right to subscribe share(s) at a stated price for a specified period of time.

        "Period of restriction" means the period during which the Management Board can suspend the right for employees to exercise the options.

        "Share" means the common share of the Company, par value € 3.82 per share.

        "Stock Option Plan" means the Aventis stock option plan 2003.

        Gender and Number:    Except when otherwise indicated by the context, words in the masculine gender used in the Stock Option Plan shall include the feminine gender, the singular shall include the plural, and the plural shall include the singular.

III.  DESCRIPTION OF THE AVENTIS STOCK OPTION PLAN

Optionees

        The Management Board has laid down the list of beneficiaries of the Stock Option Plan.

Number of shares

        The maximum number of shares each beneficiary may apply for is given on the individual letter addressed by the Chairman, or his duly designated representative.

Share subscription price

The Management Board has set the subscription price on the basis of the average price (on the basis of the closing prices) quoted during the last twenty days trading on the Paris stock exchange prior to the Management Board decision in accordance with the legal and statutory provisions in force.

        It will remain fixed during the entire Stock Option Plan subject to its adjustment by the Management Board according to the terms and conditions set out in these regulations.

Duration of the options

        The options are granted irrevocably for a duration of 10 years from the day they are allotted by the Management Board.

        Options that have not been exercised at the end of the 10-year period will be declared null and void. No extensions will be granted.

10

        The options will not be exercisable within the first three years. However, the beneficiaries deemed to be resident in France for tax purposes will be entitled to exercise their options only after a four-year period from the date of the grant, unless they keep the shares on the asset register until the end of the said four-year period, and except if this exercising before four years no longer leads to the payment of social security contributions by the Company on the capital gains made by the beneficiaries following a change in the French regulations in force.

        The rights resulting from the options granted are non-transferable.

Adjusting the subscription price and the number of shares

        Should the Company carry out any of the following financial operations before the options have expired, the subscription price of the shares and the number of shares that can be subscribed for by each beneficiary will be adjusted by the Management Board under the following conditions:

1.

In the case of the issue, reserved for the shareholders, of shares to be subscribed in cash, or convertible or exchangeable bonds or bond warrants, the subscription price of the shares under option will be reduced by an amount equal to the product of this price through the ratio between the value of the subscription right and the value of the share before removal of this right.

        The ratio will be calculated as follows:

•

The value of the share before removal of the subscription right will be equal to the average of twenty consecutive opening prices chosen from the forty trading days preceding the opening day of the issue.



•

The value of the subscription right will be the theoretical value calculated according to the number of new shares issued to which an existing share gives entitlement, the issue price of these new shares and the value of the share before removal of the subscription right.



2.

In the case of an increase in capital through incorporation of reserves, profit or premiums and distribution of bonus shares, the subscription price of the shares under option will be adjusted by the application of a coefficient equal to the ratio between the number of old shares and the number of shares existing after the operation.



3.

In the case of distribution of reserves into cash or into portfolio securities, the subscription price of the shares under option will be reduced by an amount equal to the product of this price multiplied by the ratio between the amount per share of the distribution and the value of the share before distribution.

        For the calculation of this ratio, if the Company shares and the securities distributed are allowed in transactions on a regulated market, the value of the securities distributed and the value of the share before distribution will be equal to the average of the first prices quoted during the thirty trading days of the stock exchange prior to the start of the distribution.

        If the shares of the Company or the securities distributed are not allowed in transactions on a regulated market, the Management Board will fix the values upon review of the auditors' special report.

4.

In the case of a reduction of capital due to losses.



•

If the reduction focuses on the number of shares, the subscription price will be adjusted by appropriating to it a coefficient equal to the ratio between the number of old shares and the number of shares remaining after reduction.



•

If the reduction focuses on the nominal value of the shares, there will be no adjustment.

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        In all the cases mentioned above, an adjustment in the number of shares under option will be made so that the total subscription prices remain constant. The number adjusted will however be rounded up to the higher figure.

Change of Control

        The 'Change of Control' will be considered as 'effective' from:

(a)

the date of publication in the official list of the notice of the result of the takeover bid by Euronext Paris, in the case of a takeover bid or a public offer of exchange.



(b)

the date of the notification to the Company of the crossing of the threshold level having taken the interest of a shareholder to at least 20% of the voting rights in the Company, in the case of entry into the capital of a new shareholder holding at least 20% of the voting rights in the shareholders' meeting or the increase in the previous interest of a new shareholder taking his/her interest to at least 20% of the voting rights in the shareholders' meeting.



(c)

the date of the general meeting approving the demerger, transferral or contribution of the principal assets of the Company or the merger, in the case of demerger, contribution or transfer of the principal assets of the Company or merger.



(d)

the date of the general meeting appointing the new management and administration structure, in the case of the direct or indirect intervention of a rival company in the management and administration structure of the Company.

        In the case of 'Change of Control':

1.

The Company will do its best to ensure sufficient liquidity allowing the options to be exercised under normal conditions.



2.

If the Aventis shares ceased to be quoted on a regulated market, it would be requested of the company responsible for the 'Change of Control' to take over the existing patrimonial commitments with regard to the beneficiaries and as a consequence to implement one of the following solutions:



•

either to undertake to buy back from the beneficiaries the shares obtained following the exercise of their options, on the date when they will present them, this date obligatorily being during the exercise period initially decided for the options. In the case where the Company is subject to a procedure of obligatory withdrawal, the shares obtained by the beneficiaries must obligatorily be presented for repurchase following the exercise of the options.

The price of the repurchase will be equal to that of the Aventis share on the date when the Change of Control becomes effective or on the first date of quotation following this date, and would vary both upwards and downwards between this date and the date of the request for repurchase, according to the evolution of the price of the share of the Company which is the beneficiary of the 'Change of Control' over the same period.

•

or to grant the beneficiaries, in exchange for their old options, new options.

If these commitments are not carried out, the resulting loss to the beneficiaries will be estimated by an expert designated by the two parties, or if no agreement can be found, by the President of the Paris Tribunal de Commerce (commercial court), who will give a ruling on the petition of the more diligent party.

The amount decided would be paid by the Company, or by any company that it will substitute for or that will substitute for it.

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To decide this loss, the expert will take into account the price of the share on the date when the Change of Control becomes effective or on the first date of quotation following this change and the 'time value' still left to run until the final date for the exercise of the considered options taking into account all the existing corporate or tax incidences.

IV.    EXERCISE OF THE OPTIONS

Exercising conditions

        The exercise of the options by an optionee is subject to the condition that he/she is actively employed by, or has a corporate mandate with, the Company or one of the Companies of the Aventis Group on the date of the exercise, unless otherwise decided by the Management Board in exceptional cases.

        By Company of the Aventis Group, it is meant any company or group of economic interests where at least 10% of the capital or voting rights is held directly or indirectly by the Company, on the date of exercise.

        Notwithstanding the provisions of the preceding paragraphs:

•

In the case of (i) resignation, (ii) lay-off, redundancy or other termination at the employer's initiative (except for serious professional misconduct), (iii) expiration of a limited duration work contract or (iv) revocation of a corporate mandate (except for serious professional misconduct), the options can, whatever the case, be exercised for a maximum period of 6 months from the date of departure from the employing company (in the case of resignation or termination), the date of expiration of the work contract or the date of the revocation, subject to their being exercisable on such date of departure, expiration or revocation. Options that are not exercisable on such date of departure, expiration or revocation will be lost.



•

If the prior formal approval of the Management Board is obtained, in the case of lay-off, redundancy or other termination at the employer's initiative resulting from a collective headcount reduction scheme (except in the case of serious professional misconduct), the options can be exercised for a period of 12 months from the effective date of the termination or from the Opening Day of the Exercise Period of the options if this date is later, provided that this period cannot exceed the termination date of the options. Opening Day of the Exercise Period means it is the day from which the options are exercisable as stipulated in the paragraph "Duration of the options".



•

However, if a lay-off, redundancy or other termination at the employer's initiative (except for serious professional misconduct), expiration of a work contract or revocation (except for serious professional misconduct) takes place within eighteen months following a Change of Control of the Company, the options can be exercised until the expiration of the plan under the same conditions as if the optionee were still employed or held a corporate mandate.



•

In the case of dismissal or revocation for serious professional misconduct, the departure from the employing company automatically cancels those options not yet exercised with effect from the date of notification of such dismissal or revocation.



•

In the case of the transfer of a Company of the Aventis Group or an activity of a Company of the Aventis Group to a company where Aventis does not hold directly or indirectly at least 10% of the capital or voting rights, or in the case of transfer by flotation, the options can be exercised until the expiration of the plan under the same conditions as if the optionee were still employed or held a corporate mandate.

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•

In the case of the death of the optionee, the heirs who wish to exercise the options must do so under the conditions fixed by French law, which at the moment stipulate that the options are exercisable for a period of six months from the date of death.



•

Except in the case of serious professional misconduct, the options can be exercised until the expiration of the plan under the same conditions as if the optionee were still employed or held a corporate mandate, in the following cases:



•

Disability,



•

Employee or holder of a corporate mandate, aged 55 or more, retiring at the employer's initiative or taking early retirement at the employer's initiative,



•

Employee or holder of a corporate mandate, aged 55 or more and having at least 10 years of seniority in the Aventis Group, retiring,



•

Lay-off, redundancy or other termination at the employer's initiative (except for serious professional misconduct) of an employee aged 55 or more,



•

Revocation or early termination of the corporate mandate (except for serious professional misconduct) of a mandate holder aged 55 or more.

Period of restriction

        The Management Board can suspend the right to exercise the options if necessary, notably when trading on Aventis capital requires the exact and prior knowledge of the number of shares that make up the capital or in the case of one of the financial operations leading to an adjustment being carried out.

        In these cases, the Company will inform the beneficiaries of the suspension date and the date when the options can be exercised again. Such a suspension cannot extend the exercise period beyond the original 10-year period.

        In order to reduce the risk of unintentional insider trading, the Management Board can also suspend the right to exercise the options temporarily during identified "Black-Out Periods", which are periods of time when significant confidential information is circulating within the company. This includes the approximately 30-day period between the end of each fiscal year or quarter and the public announcement of earnings for that year or quarter. During a "Black-Out period", employees who are considered likely to be aware of such confidential information are blocked from exercising stock options until the "black-out period" expires.

Methods of the exercise of the options

        The exercise of the options is at the discretion of the beneficiaries.

        The options can be exercised partially or in totality.

        To exercise an option, the beneficiaries must apply to the Plan Manager whose details will have been provided.

        Costs incurred in exercising an option by the Plan Manager will be born by the beneficiaries.

V.     CHARACTERISTICS OF SUBSCRIBED SHARES

Form and delivery of stocks

        Shares subscribed for by beneficiaries who are French residents must take the registered form. If this is not the case, their holders will lose the benefit of the special tax system for stock options.

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        Unless instructions to the contrary are received from the beneficiaries, the stocks will be registered in an individual account opened in the Plan Manager's books.

Interest

        The new shares will be created with coupon attached and will be immediately entitled to the same dividend as the other shares which make up the capital of Aventis, subject to having been subscribed during the fiscal year for which the first dividend will be paid to them.

        Shares subscribed between the first day of the fiscal year and the date of distribution of the dividend in that year in respect of the previous fiscal year will not give entitlement to the dividend relating to this previous fiscal year and will be subject to a specific quotation on the market of the Paris Bourse until the date of distribution of the said dividend.

VI.   TRANSFER OF SHARES

        Subject to the period inherent in preliminary formalities for the quotation on the stock market of new shares and possibly the application of a tax system which is less favourable in the case of non-compliance with legal conditions concerning time of tenure and form, the shares acquired following the exercise of options can be sold immediately.

        To carry out this sale, the beneficiaries must address a selling order to the Plan Manager, in accordance with the model sent by the latter.

        Requests to exercise options will be recorded on a register timed and dated, which will be held by each Plan Manager.

VII MANAGEMENT OF THE PLAN

        The administrative management of the Stock Option Plan has been entrusted to banks selected by Aventis (each one a 'Plan Manager'). The beneficiaries will be informed of the details of the Plan Manager who they can contact for any information.

        Aventis reserves the right to entrust to a new bank the administrative management of the stock option plan, after prior information to the beneficiaries.

VIII MISCELLANEOUS

        As some beneficiaries are not French residents, the Management Board could, depending on the conditions imposed by certain countries, with regard to the exercise of options and the subsequent transfer of options, modify certain provisions of the plan concerning beneficiaries working in these countries, without these modifications making the plan more favourable for these beneficiaries (apart from aspects relating to the tax systems of these countries).

        Nothing in the Plan shall interfere or limit in any way the right of the employer to terminate any beneficiary's employment at any time, nor confer upon any beneficiary any right to continue in employ of their company. No beneficiary shall have a right to be selected as a beneficiary, or, having been so selected, to receive any future options.

Securities offered to persons who are not residents or citizens of the United States of America have not been and will not be registered under the U.S. Securities Act of 1933, as amended (the "Act") and may not be offered or sold in the United States unless registered under the Act or an exemption from registration is available.

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RULES AND REGULATIONS FOR
AVENTIS STOCK SUBSCRIPTION OPTION

GRANT of December 2, 2003

ANNEX

Authorization of the Option Plan	:	General Shareholders Meeting of May 14, 2002.
Decision and date of grant	:	Management Board of December 2, 2003
Number of options allotted	:	10 232 797
Reference price (average price quoted from November 4, 2003 to December 1, 2003)	:	€ 47.52
Exercise price	:	€ 47.52
Vesting date	:	December 3, 2006 except for French tax residents (December 3, 2007 for French tax residents)
Exercise period	:	From December 3, 2006 through December 2, 2013 inclusive (From December 3, 2007 through December 2, 2013, inclusive for French tax residents)

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Exhibit 4.2

EX-5

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Exhibit 5

AVENTIS LETTERHEAD

December 5, 2003

Aventis
Strasbourg, France

Re:    Aventis Stock Option Plan 2003

Gentlemen:

        I have acted as counsel to Aventis (the "Company") in connection with the registration with the Securities and Exchange Commission on Form S-8 of Ordinary Shares, nominal value €3.82 per share, of the Company (the "Shares"), that will be issuable upon exercise of options granted under the above-referenced plan (the "Plan"). In connection with such registration, I have reviewed the proceedings of the Board of Management of the Company relating to the registration and proposed issuance of the Shares, the Articles of Association of the Company and all amendments thereto, and such other documents and matters as I have deemed necessary to the rendering of the following opinion.

        Based upon that review, it is my opinion that the Shares, when issued in conformance with the terms and conditions of the Plan, will be legally issued, fully paid, and nonassessable under the laws of France.

        I consent to the use of this opinion in the registration statement filed with the Securities and Exchange Commission in connection with the registration of the Shares.

Very truly yours,

/s/  BRUNO ANGRAND Bruno Angrand
Vice President
Head of Corporate Law
Aventis

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Exhibit 5

EX-23.1

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Exhibit 23.1

Consent of PricewaterhouseCoopers (Paris)

        We consent to the incorporation by reference in the Registration Statement on Form S-8 of Aventis relating to the Aventis Stock Option Plan 2003, of our report dated February 4, 2003, relating to the consolidated balance sheets of Aventis and its subsidiaries as of December 31, 2002 and 2001, and the related consolidated statements of operations, stockholders' equity and cash flows for each of the three years in the period ended December 31, 2002, which is included in the Annual Report on Form 20-F of Aventis for the year ended December 31, 2002.

December 23, 2003

/s/  PRICEWATERHOUSECOOPERS PricewaterhouseCoopers (Paris)
Independent Auditors

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Exhibit 23.1