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                                                                    EXHIBIT 3.3

                          CERTIFICATE OF DETERMINATION

                                       OF

                  SERIES A JUNIOR PARTICIPATING PREFERRED STOCK

                                       OF

                               ARADIGM CORPORATION

                         (Pursuant to Section 401 of the
                       California General Corporation Law)


        The undersigned, Richard P. Thompson and Reid M. Rubsamen hereby certify
that:

        1. They are the duly elected and acting Chief Executive Officer and
President, and Secretary, respectively, of Aradigm Corporation (the
"Corporation").

        2. Pursuant to authority given by the Corporation's Articles of
Incorporation, the Board of Directors of the Corporation has duly adopted the
following resolutions at a meeting duly called and held on August 4, 1998:

                RESOLVED, that pursuant to the authority granted to and vested
        in the Board of Directors of the Corporation in accordance with the
        provisions of its Restated Articles of Incorporation, the Board of
        Directors hereby creates a series of Preferred Stock, without par value,
        of the Corporation and hereby states the designation and number of
        shares, and fixes the relative rights, preferences, privileges and
        restrictions thereof (in addition to the provisions set forth in the
        Restated Articles of Incorporation of the Corporation, which are
        applicable to the Preferred Stock of all classes and series), as
        follows:

                Series A Junior Participating Preferred Stock:

                     SECTION 1. DESIGNATION AND AMOUNT. Two Hundred Thirty
        Thousand (230,000) shares of Preferred Stock, without par value, are
        designated "Series A Junior Participating Preferred Stock" with the
        rights, preferences, privileges and restrictions specified herein (the
        "Junior Preferred Stock"). Such number of shares may be increased or
        decreased by resolution of the Board of Directors; provided, that no
        decrease shall reduce the number of shares of Junior Preferred Stock to
        a number less than the number of shares then outstanding plus the number
        of shares reserved for issuance upon the exercise of outstanding



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        options, rights or warrants or upon the conversion of any outstanding
        securities issued by the Corporation convertible into Junior Preferred
        Stock.

                SECTION 2. DIVIDENDS AND DISTRIBUTIONS.

                (A) Subject to the rights of the holders of any shares of any
        series of Preferred Stock (or any similar stock) ranking prior and
        superior to the Junior Preferred Stock with respect to dividends, the
        holders of shares of Junior Preferred Stock, in preference to the
        holders of Common Stock, without par value (the "Common Stock"), of the
        Corporation, and of any other junior stock, shall be entitled to
        receive, when, as and if declared by the Board of Directors out of funds
        legally available for the purpose, quarterly dividends payable in cash
        on the first day of March, June, September and December in each year
        (each such date being referred to herein as a "Quarterly Dividend
        Payment Date"), commencing on the first Quarterly Dividend Payment Date
        after the first issuance of a share or fraction of a share of Junior
        Preferred Stock, in an amount per share (rounded to the nearest cent)
        equal to the greater of (a) $1.00 or (b) subject to the provision for
        adjustment hereinafter set forth, 100 times the aggregate per share
        amount of all cash dividends, and 100 times the aggregate per share
        amount (payable in kind) of all non-cash dividends or other
        distributions, other than a dividend payable in shares of Common Stock
        or a subdivision of the outstanding shares of Common Stock (by
        reclassification or otherwise) declared on the Common Stock since the
        immediately preceding Quarterly Dividend Payment Date or, with respect
        to the first Quarterly Dividend Payment Date, since the first issuance
        of any share or fraction of a share of Junior Preferred Stock. In the
        event the Corporation shall at any time declare or pay any dividend on
        the Common Stock payable in shares of Common Stock, or effect a
        subdivision or combination or consolidation of the outstanding shares of
        Common Stock (by reclassification or otherwise than by payment of a
        dividend in shares of Common Stock) into a greater or lesser number of
        shares of Common Stock, then in each such case the amount to which
        holders of shares of Junior Preferred Stock were entitled immediately
        prior to such event under clause (b) of the preceding sentence shall be
        adjusted by multiplying such amount by a fraction, the numerator of
        which is the number of shares of Common Stock outstanding immediately
        after such event and the denominator of which is the number of shares of
        Common Stock that were outstanding immediately prior to such event.

                (B) The Corporation shall declare a dividend or distribution on
        the Junior Preferred Stock as provided in paragraph (A) of this Section
        immediately after it declares a dividend or distribution on the Common
        Stock (other than a dividend payable in shares of Common Stock);
        provided that, in the event no dividend or distribution shall have been
        declared on the Common Stock during the period between any Quarterly
        Dividend Payment Date and the next subsequent Quarterly Dividend Payment
        Date, a dividend of $1.00 per share on the Junior Preferred Stock shall
        nevertheless be payable on such subsequent Quarterly Dividend Payment
        Date.



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                (C) Dividends shall begin to accrue and be cumulative on
        outstanding shares of Junior Preferred Stock from the Quarterly Dividend
        Payment Date next preceding the date of issue of such shares, unless the
        date of issue of such shares is prior to the record date for the first
        Quarterly Dividend Payment Date, in which case dividends on such shares
        shall begin to accrue from the date of issue of such shares, or unless
        the date of issue is a Quarterly Dividend Payment Date or is a date
        after the record date for the determination of holders of shares of
        Junior Preferred Stock entitled to receive a quarterly dividend and
        before such Quarterly Dividend Payment Date, in either of which events
        such dividends shall begin to accrue and be cumulative from such
        Quarterly Dividend Payment Date. Accrued but unpaid dividends shall not
        bear interest. Dividends paid on the shares of Junior Preferred Stock in
        an amount less than the total amount of such dividends at the time
        accrued and payable on such shares shall be allocated pro rata on a
        share-by-share basis among all such shares at the time outstanding. The
        Board of Directors may fix a record date for the determination of
        holders of shares of Junior Preferred Stock entitled to receive payment
        of a dividend or distribution declared thereon, which record date shall
        be not more than 60 days prior to the date fixed for the payment
        thereof.

                SECTION 3. VOTING RIGHTS. The holders of shares of Junior
        Preferred Stock shall have the following voting rights:

                (A) Subject to the provision for adjustment hereinafter set
        forth, each share of Junior Preferred Stock shall entitle the holder
        thereof to 100 votes on all matters submitted to a vote of the
        shareholders of the Corporation. In the event the Corporation shall at
        any time declare or pay any dividend on the Common Stock payable in
        shares of Common Stock, or effect a subdivision or combination or
        consolidation of the outstanding shares of Common Stock (by
        reclassification or otherwise than by payment of a dividend in shares of
        Common Stock) into a greater or lesser number of shares of Common Stock,
        then in each such case the number of votes per share to which holders of
        shares of Junior Preferred Stock were entitled immediately prior to such
        event shall be adjusted by multiplying such number by a fraction, the
        numerator of which is the number of shares of Common Stock outstanding
        immediately after such event and the denominator of which is the number
        of shares of Common Stock that were outstanding immediately prior to
        such event.

                (B) Except as otherwise provided herein, in any other
        Certificate of Determination of Preferences creating a series of
        Preferred Stock or any similar stock, or by law, the holders of shares
        of Junior Preferred Stock and the holders of shares of Common Stock and
        any other capital stock of the Corporation having general voting rights
        shall vote together as one class on all matters submitted to a vote of
        shareholders of the Corporation.

                (C) Except as set forth herein, or as otherwise provided by law,
        holders of Junior Preferred Stock shall have no special voting rights
        and their



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        consent shall not be required (except to the extent they are entitled to
        vote with holders of Common Stock as set forth herein) for taking any
        corporate action.

                SECTION 4. CERTAIN RESTRICTIONS.

                (A) Whenever quarterly dividends or other dividends or
        distributions payable on the Junior Preferred Stock as provided in
        Section 2 are in arrears, thereafter and until all accrued and unpaid
        dividends and distributions, whether or not declared, on shares of
        Junior Preferred Stock outstanding shall have been paid in full, the
        Corporation shall not:

                     (i) declare or pay dividends, or make any other
        distributions, on any shares of stock ranking junior (either as to
        dividends or upon liquidation, dissolution or winding up) to the Junior
        Preferred Stock;

                     (ii) declare or pay dividends, or make any other
        distributions, on any shares of stock ranking on a parity (either as to
        dividends or upon liquidation, dissolution or winding up) with the
        Junior Preferred Stock, except dividends paid ratably on the Junior
        Preferred Stock and all such parity stock on which dividends are payable
        or in arrears in proportion to the total amounts to which the holders of
        all such shares are then entitled;

                     (iii) redeem or purchase or otherwise acquire for
        consideration shares of any stock ranking junior (either as to dividends
        or upon liquidation, dissolution or winding up) to the Junior Preferred
        Stock, provided that the Corporation may at any time redeem, purchase or
        otherwise acquire shares of any such junior stock in exchange for shares
        of any stock of the Corporation ranking junior (either as to dividends
        or upon dissolution, liquidation or winding up) to the Junior Preferred
        Stock; or

                     (iv) redeem or purchase or otherwise acquire for
        consideration any shares of Junior Preferred Stock, or any shares of
        stock ranking on a parity with the Junior Preferred Stock, except in
        accordance with a purchase offer made in writing or by publication (as
        determined by the Board of Directors) to all holders of such shares upon
        such terms as the Board of Directors, after consideration of the
        respective annual dividend rates and other relative rights and
        preferences of the respective series and classes, shall determine in
        good faith will result in fair and equitable treatment among the
        respective series or classes.

                (B) The Corporation shall not permit any subsidiary of the
        Corporation to purchase or otherwise acquire for consideration any
        shares of stock of the Corporation unless the Corporation could, under
        paragraph (A) of this Section 4, purchase or otherwise acquire such
        shares at such time and in such manner.

                SECTION 5. REACQUIRED SHARES. Any shares of Junior Preferred
        Stock purchased or otherwise acquired by the Corporation in any manner
        whatsoever shall be retired and cancelled promptly after the acquisition
        thereof.



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        All such shares shall upon their cancellation become authorized but
        unissued shares of Preferred Stock and may be reissued as part of a new
        series of Preferred Stock subject to the conditions and restrictions on
        issuance set forth herein, in the Restated Articles of Incorporation, or
        in any other Certificate of Determination of Preferences creating a
        series of Preferred Stock or any similar stock or as otherwise required
        by law.

                SECTION 6. LIQUIDATION, DISSOLUTION OR WINDING UP. Upon any
        liquidation, dissolution or winding up of the Corporation, no
        distribution shall be made (1) to the holders of shares of stock ranking
        junior (either as to dividends or upon liquidation, dissolution or
        winding up) to the Junior Preferred Stock unless, prior thereto, the
        holders of shares of Junior Preferred Stock shall have received the
        greater of: (A) $100 per share, plus an amount equal to accrued and
        unpaid dividends and distributions thereon, whether or not declared, to
        the date of such payment; or (B) an aggregate amount per share, subject
        to the provision for adjustment hereinafter set forth, equal to 100
        times the aggregate amount to be distributed per share to holders of
        shares of Common Stock, or (2) to the holders of shares of stock ranking
        on a parity (either as to dividends or upon liquidation, dissolution or
        winding up) with the Junior Preferred Stock, except distributions made
        ratably on the Junior Preferred Stock and all such parity stock in
        proportion to the total amounts to which the holders of all such shares
        are entitled upon such liquidation, dissolution or winding up. In the
        event the Corporation shall at any time declare or pay any dividend on
        the Common Stock payable in shares of Common Stock, or effect a
        subdivision or combination or consolidation of the outstanding shares of
        Common Stock (by reclassification or otherwise than by payment of a
        dividend in shares of Common Stock) into a greater or lesser number of
        shares of Common Stock, then in each such case the aggregate amount to
        which holders of shares of Junior Preferred Stock were entitled
        immediately prior to such event under the proviso in clause (1) of the
        preceding sentence shall be adjusted by multiplying such amount by a
        fraction the numerator of which is the number of shares of Common Stock
        outstanding immediately after such event and the denominator of which is
        the number of shares of Common Stock that were outstanding immediately
        prior to such event.

                SECTION 7. CONSOLIDATION, MERGER, ETC. In case the Corporation
        shall enter into any consolidation, merger, combination or other
        transaction in which the shares of Common Stock are exchanged for or
        changed into other stock or securities, cash and/or any other property,
        then in any such case each share of Junior Preferred Stock shall at the
        same time be similarly exchanged or changed into an amount per share,
        subject to the provision for adjustment hereinafter set forth, equal to
        100 times the aggregate amount of stock, securities, cash and/or any
        other property (payable in kind), as the case may be, into which or for
        which each share of Common Stock is changed or exchanged. In the event
        the Corporation shall at any time declare or pay any dividend on the
        Common Stock payable in shares of Common Stock, or effect a subdivision
        or combination or consolidation of the outstanding shares of Common
        Stock (by reclassification or otherwise than by payment of a dividend in
        shares of Common Stock) into a



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        greater or lesser number of shares of Common Stock, then in each such
        case the amount set forth in the preceding sentence with respect to the
        exchange or change of shares of Junior Preferred Stock shall be adjusted
        by multiplying such amount by a fraction, the numerator of which is the
        number of shares of Common Stock outstanding immediately after such
        event and the denominator of which is the number of shares of Common
        Stock that were outstanding immediately prior to such event.

                SECTION 8. NO REDEMPTION. The shares of Junior Preferred Stock
        shall not be redeemable.

                SECTION 9. RANK. The Junior Preferred Stock shall rank, with
        respect to the payment of dividends and the distribution of assets,
        junior to all other series of the Corporation's Preferred Stock.

                SECTION 10. AMENDMENT. The Restated Articles of Incorporation of
        the Corporation shall not be amended in any manner which would
        materially alter or change the powers, preferences or special rights of
        the Junior Preferred Stock so as to affect them adversely without the
        affirmative vote of the holders of at least two-thirds of the
        outstanding shares of Junior Preferred Stock, voting together as a
        single class.

        3. The authorized number of shares of Preferred Stock of this
corporation is 5,000,000, and the number of shares of Preferred Stock
constituting Series A Junior Preferred Stock, none of which has been issued, is
230,000.



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        IN WITNESS WHEREOF, the undersigned have executed this certificate on
August 31, 1998.



                                    /s/ Richard P. Thompson
                                    --------------------------------------------
                                    RICHARD P. THOMPSON
                                    CHIEF EXECUTIVE OFFICER AND PRESIDENT



                                    /s/ Reid M. Rubsamen
                                    --------------------------------------------
                                    REID M. RUBSAMEN
                                    SECRETARY

        The undersigned Richard P. Thompson, Chief Executive Officer and
President of Aradigm Corporation and Reid M. Rubsamen, Secretary of said
corporation, each certifies under penalty of perjury that the matters set forth
in the foregoing Certificate of Determination are true of their own knowledge.


        Executed at Hayward, California on August 31, 1998.



                                    /s/ Richard P. Thompson
                                    --------------------------------------------
                                    RICHARD P. THOMPSON
                                    CHIEF EXECUTIVE OFFICER AND PRESIDENT



        Executed at Hayward, California on August 31, 1998.

                                    /s/ Reid M. Rubsamen
                                    --------------------------------------------
                                    REID M. RUBSAMEN
                                    SECRETARY



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