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                                                                     Exhibit 3.1



                      RESTATED CERTIFICATE OF INCORPORATION
                                       OF
                                   DYAX CORP.

         The undersigned, for the purpose of amending and restating the Amended
and Restated Certificate of Incorporation of Dyax Corp. (the "Corporation")
under the laws of the State of Delaware, hereby certifies as follows:

         A. The Corporation was incorporated under the name Biotage, Inc.
pursuant to an original Certificate of Incorporation filed with the Secretary of
State of the State of Delaware on May 26, 1989.

         B. The amendments to and the restatement of the Amended and Restated
Certificate of Incorporation of the Corporation herein certified have been
approved by the Board of Directors of the Corporation and duly adopted by the
stockholders of the Corporation in accordance with the provisions of Sections
228, 242 and 245 of the General Corporation Law of the State of Delaware. Prompt
written notice of the adoption of the amendments herein certified has been given
to those stockholders who have not consented in writing thereto, as provided in
Section 228 of the General Corporation Law of the State of Delaware.

         C. The Amended and Restated Certificate of Incorporation of the
Corporation, as previously amended and restated, is hereby restated and further
amended to read as follows:

FIRST:  The name of the Corporation is DYAX CORP.

SECOND: The address of the Corporation's registered office in the State of
Delaware is 1013 Centre Road, City of Wilmington, County of Newcastle, State of
Delaware 19805. The name of its registered agent at such address is Corporation
Service Company.

THIRD:  The nature of the business or purposes to be conducted or promoted are:

     To engage in any lawful act or activity for which corporations may be
organized under the General Corporation Law of Delaware.

FOURTH:  The authorized capitalization of the Corporation is as follows:

                            PART 1: AUTHORIZED SHARES

         The total number of shares of all classes of stock which the
Corporation shall have authority to issue is thirty-four million nine hundred
forty five thousand four hundred nineteen (34,945,419) shares, of which twenty
million (20,000,000) shares, par value $0.01 per share, are to be of a class
designated "Common Stock", and fourteen million nine hundred forty five thousand
four hundred nineteen (14,945,419) shares, par value $0.01 per share, are to be
of a class designated "Class A Preferred Stock".


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                                PART 2: ISSUANCE

         Subject to the provisions of this Certificate of Incorporation and
except as otherwise provided by law, the shares of stock of the Corporation,
regardless of class, may be issued for such consideration and for such corporate
purposes as the Board of Directors may from time to time determine.

                              PART 3: COMMON STOCK

         Subject to the provisions of any applicable law or of the by-laws of
the Corporation, as from time to time amended, with respect to the fixing of a
record date for the determination of stockholders entitled to vote, and except
as otherwise provided by law, by this Certificate of Incorporation or by the
resolution or resolutions providing for the issue of any series of the Class A
Preferred Stock, the holders of outstanding shares of Common Stock shall have
voting rights for the election of directors and for all other purposes, each
holder of record of shares of Common Stock being entitled to one vote for each
share of Common Stock standing in his name on the books of the Corporation,
which voting rights shall not be cumulative.

         Subject to the rights of any one or more series of the Class A
Preferred Stock, the holders of Common Stock shall be entitled to receive such
dividends as from time to time may be declared by the Board of Directors out of
any funds of the Corporation legally available for the payment of such
dividends.

         In the event of the liquidation, dissolution, or winding up of the
Corporation, whether voluntary or involuntary, after payment shall have been
made to the holders of the Class A Preferred Stock of the full amount to which
they are entitled, the holders of Common Stock shall be entitled to share,
ratably according to the number of shares of Common Stock held by them, in all
remaining assets of the Corporation available for distribution to its
stockholders.

         The number of authorized shares of Common Stock may be increased or
decreased (but not below the number of shares thereof then outstanding) by the
affirmative vote of the holders of a majority of all shares of capital stock of
the Corporation then outstanding and entitled to vote thereon, voting together
as a single class, irrespective of the provisions of Section 242 of the General
Corporation Law of the State of Delaware that would otherwise require a vote of
the holders of Common Stock as a separate class.

                             PART 4: PREFERRED STOCK

         The Board of Directors is authorized, subject to limitations prescribed
by law and the provisions of this Article Fourth, to provide by resolution for
the issuance of the shares of Class A Preferred Stock in one or more series, and
by filing a certificate pursuant to the applicable law of the State of Delaware,
to establish from time to time the number of shares to be included in


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each such series, and to fix the designations, powers, preferences and rights of
the shares of each such series and the qualifications, limitations or
restrictions thereof.

         The authority of the Board with respect to each series of Class A
Preferred Stock shall include, but not be limited to, determination of the
following:

         (a)      The number of shares constituting that series and the
                  distinctive designation of that series;

         (b)      The dividend rate, if any, on the shares of that series,
                  whether dividends shall be cumulative, and if so, from which
                  date or dates, and the relative rights of priority, if any, of
                  payment of dividends on shares of the series;

         (c)      Whether that series shall have voting rights, in addition to
                  the voting rights provided by law, and, if so, the terms of
                  such voting rights;

         (d)      Whether that series shall have conversion privileges, and, if
                  so, the terms and conditions of such conversion, including
                  provision for adjustment of the conversion rate in such events
                  as the Board of Directors shall determine;

         (e)      Whether or not the shares of that series shall be redeemable,
                  and, if so, the terms and conditions of such redemption,
                  including the date or dates upon or after which they shall be
                  redeemable, and the amount per share payable in case of
                  redemption, which amount may vary under different conditions
                  and at different redemption dates;

         (f)      Whether that series shall have a sinking fund for the
                  redemption or purchase of shares of that series, and, if so,
                  the terms and amount of such sinking fund;

         (g)      The rights of the shares of that series in the event of
                  voluntary or involuntary liquidation, dissolution or winding
                  up of the Corporation, and the relative rights of priority, if
                  any, of payment of shares of that series; and

         (h)      Any other relative rights, preferences and limitations of that
                  series.

 PART 5: CLASS A SERIES 1, CLASS A SERIES 2, CLASS A SERIES 3, CLASS A SERIES 4
                      AND CLASS A SERIES 5 PREFERRED STOCK

                  1. DESIGNATION OF CLASS A SERIES 1 PREFERRED STOCK, CLASS A
SERIES 2 PREFERRED STOCK, CLASS A SERIES 3 PREFERRED STOCK, CLASS A SERIES 4 AND
CLASS A SERIES 5 PREFERRED STOCK. One million nine hundred forty-four thousand
five hundred (1,944,500) shares of Class A Preferred Stock are hereby designated
as "Class A Series 1 Preferred Stock", seven hundred four thousand (704,000)
shares of Class A Preferred Stock are hereby designated as "Class A Series 2
Preferred Stock", two million (2,000,000) shares of Class A Preferred Stock are
hereby designated as "Class A Series 3 Preferred Stock", four million seven
hundred ninety-two thousand three hundred thirty-two (4,792,332) shares of Class
A Preferred Stock are hereby designated "Class A Series 4 Preferred Stock", and
five million five hundred four thousand five hundred eighty seven (5,504,587)
shares of Class A Preferred Stock are hereby designated


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"Class A Series 5 Preferred Stock". As used herein, the term "Class A Preferred
Stock", used without reference to Class A Series 1 Preferred Stock, Class A
Series 2 Preferred Stock, Class A Series 3 Preferred Stock, Class A Series 4
Preferred Stock, or Class A Series 5 Preferred Stock means the Class A Series 1
Preferred Stock, the Class A Series 2 Preferred Stock, the Class A Series 3
Preferred Stock, the Class A Series 4 Preferred Stock, the Class A Series 5
Preferred Stock and any other series of Class A Preferred Stock that may be
established from time to time by the Board of Directors in accordance with this
Article Fourth, share for share alike and without distinction as to series,
except as otherwise expressly provided or as the context otherwise requires.

         2. DIVIDENDS. When and as dividends are duly declared by the Board of
Directors of the Corporation, the holders of the Class A Preferred Stock shall
be entitled to receive, out of any funds legally available for that purpose,
dividends (other than dividends payable in shares of Common Stock) at the same
rate as dividends declared with respect to shares of Common Stock. In connection
with the determination of such dividends, each share of the Class A Preferred
Stock shall be deemed to represent that number of shares of Common Stock into
which it is convertible. Dividends declared on each series of the Class A
Preferred Stock shall be paid PARI PASSU with dividends declared on any other
series of Class A Preferred Stock and with any dividends declared on the Common
Stock.

         3.       LIQUIDATION, DISSOLUTION OR WINDING UP.

         (a) In the event of any voluntary or involuntary liquidation,
dissolution or winding up of the Corporation, the holders of shares of the Class
A Preferred Stock then outstanding shall be entitled to be paid out of the
assets of the Corporation available for distribution to its stockholders, before
any payment shall be made to the holders of any stock ranking on liquidation,
dissolution or winding up junior to the Class A Preferred Stock (including
holders of Common Stock) by reason of their ownership of such shares, an amount
equal to $2.186 per share for the Class A Series 1 Preferred Stock, $6.037 per
share for the Class A Series 2 Preferred Stock, $2.00 per share for the Class A
Series 3 Preferred Stock, $3.13 per share for the Class A Series 4 Preferred
Stock, and $5.45 per share for the Class A Series 5 Preferred Stock (subject in
each case to equitable adjustment in the event of any stock dividend, stock
split, combination, reorganization, recapitalization, reclassification or other
similar event affecting such shares) plus all declared but unpaid dividends. If
upon any such liquidation, dissolution or winding up of the Corporation the
remaining assets of the Corporation available for distribution to its
stockholders shall be insufficient to pay the holders of shares of Class A
Preferred Stock the full amount to which they shall be entitled, the holders of
shares of Class A Preferred Stock and any class or series of stock ranking on
liquidation on a parity with the Series A Preferred Stock shall share PARI PASSU
in any distribution of the remaining assets and funds of the Corporation in
proportion to the respective liquidation amounts of the Class A Preferred Stock
which would otherwise be payable in respect of the shares held by them upon such
distribution if all amounts payable on or with respect to such shares were paid
in full.

         (b) After the payment of all preferential amounts required to be paid
to the holders of the Class A Preferred Stock upon the dissolution, liquidation
or winding up of the Corporation pursuant to the provisions of Section 3(a), the
remaining assets of the Corporation available for distribution, if any, to the
stockholders of the Corporation shall be allocated among the holders


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of shares of Common Stock, PRO RATA based upon the number of shares of Common
Stock then held by each.

         (c) The merger or consolidation of the Corporation into or with another
corporation or other entity with the result that the stockholders of the
Corporation receive distributions of cash, securities or other property in
complete exchange for their shares of capital stock of the Corporation, or the
sale of all or substantially all the assets of the Corporation, or a
reorganization or reclassification of capital of the Corporation, shall be
deemed to be a liquidation, dissolution or winding up of the Corporation for
purposes of this Section 3, UNLESS (i) the holders of at least 50.1% of the then
outstanding shares of Class A Preferred Stock, and with respect to the shares of
Class A Series 5 Preferred Stock, the holders of 50.1% of the then outstanding
shares of Class A Series 5 Preferred Stock, elect to have such events not deemed
to be a liquidation, dissolution or winding up of the Corporation by giving
written notice thereof to the Corporation at least 15 days before the effective
date of such event or (ii) upon consummation of such event, the holders of
voting securities of the Corporation immediately prior to such transaction
continue to own directly or indirectly not less than a majority of the voting
power of the surviving corporation. If the notice specified in clause (i) above
is given, the provisions of Subsection 5(g) below shall apply. The amount
distributed to the holders of Class A Preferred Stock upon any such merger,
consolidation or sale shall, unless otherwise prohibited by law, be equal to
that amount per share that would be received by the holders of Class A Preferred
Stock if all the consideration paid in exchange for the assets or shares of
capital stock, as the case may be, of the Corporation were actually paid to the
Corporation and the Corporation were immediately thereafter liquidated and its
assets distributed pursuant to Sections 3(a) and (b) hereof. Such amount (the
"Special Liquidation Price") shall be the sum of any cash distributed plus the
value (as determined in good faith by the Board of Directors except that any
securities included therein, to the extent that there is a public trading market
therefor, shall be valued at the closing bid price of such securities in the
public market) of any property, rights or securities distributed, and shall be
paid by the Corporation to the holders of shares of Class A Preferred Stock in
complete redemption of such shares or, if less than all of such shares may then
be legally redeemed, PRO RATA in partial redemption of such shares based upon
the liquidation amounts of the shares of Class A Preferred Stock then held by
each holder. Payment of the Special Liquidation Price will be made upon actual
delivery to the Corporation or its successor of the certificates representing
shares of Class A Preferred Stock. On and after the date of the merger,
consolidation or sale, all rights of the holders of shares of Class A Preferred
Stock to be redeemed shall terminate except the right to receive the Special
Liquidation Price, and such shares shall no longer be deemed to be outstanding,
PROVIDED, HOWEVER, that if the Corporation defaults in the payment of the
Special Liquidation Price or is otherwise unable to legally redeem all of such
shares (which inability shall be deemed to be a default) with respect to any
share of Class A Preferred Stock, the rights of the holders thereof shall
continue until the Corporation cures such default.

         4.       VOTING.

         (a) Except as otherwise expressly provided in this Section 4 or in
Section 7 hereof, or as required by law, each holder of outstanding shares of
the Class A Preferred Stock shall be


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entitled to the number of votes equal to the number of whole shares of Common
Stock into which the shares of the Class A Preferred Stock held by such holder
are convertible, at each meeting of stockholders of the Corporation (and written
actions of stockholders in lieu of meetings) with respect to any and all matters
presented to the stockholders of the Corporation for their action or
consideration. All voting for election of Directors shall be non-cumulative.
Except as otherwise expressly provided herein or as required by law, holders of
the Class A Preferred Stock shall vote together with the holders of Common Stock
as a single class.

         (b) There shall be not more than ten directors of the Corporation
without the approval, by vote or written consent, of the holders of at least
50.1% of the then outstanding shares of Class A Preferred Stock.

         (c) So long as shares of Class A Series 3 Preferred Stock are issued
and outstanding, one director of the Corporation (the "Series 3 Director") shall
be elected by the holders of Class A Series 3 Preferred Stock, voting as a
separate class. So long as shares of Class A Series 4 Preferred Stock are issued
and outstanding, one director of the Corporation (the "Series 4 Director") shall
be elected by the holders of Class A Series 4 Preferred Stock, voting as a
separate class. So long as shares of Class A Series 5 Preferred Stock are issued
and outstanding, one director of the Corporation (the "Series 5 Director") shall
be elected by the holders of Class A Series 5 Preferred Stock, voting as a
separate class. The remaining members of the Board of Directors shall be elected
by the affirmative vote of the holders of a majority of the outstanding shares
of all series of Class A Preferred Stock and Common Stock, voting together as a
class. All directors shall be elected at the annual meeting of stockholders and
shall serve until their respective successors are elected and qualified or until
their respective earlier resignation or removal. Any director who shall have
been elected by the holders of a class or series of stock may be removed during
his term of office, either for or without cause, by and only by, the affirmative
vote of the holders of a majority of the shares of the class or series of stock
who elected such director, given in writing or at a special meeting of such
stockholders duly called for that purpose. Any vacancy in the office of the
Series 3 Director, Series 4 Director, or Series 5 Director, as the case may be,
may be filled only by the holders of a majority of the outstanding shares of
Class A Series 3 Preferred Stock, Class A Series 4 Preferred Stock, or Class A
Series 5 Preferred Stock, respectively. After the close of business on the
Conversion Date on which the last issued and outstanding shares of Class A
Series 3 Preferred Stock, Class A Series 4 Preferred Stock or Class A Series 5
Preferred Stock, as the case may be, are converted pursuant to Section 5 or
Section 6, the respective director who had been elected by the Class A Series 3
Preferred Stock, Class A Series 4 Preferred Stock, or Class A Series 5 Preferred
Stock, as the case may be, shall be elected, and subject to removal, by the then
holders of Common Stock and Class A Preferred Stock, voting together as a single
class.

         5. OPTIONAL CONVERSION. The holders of the Class A Preferred Stock
shall have conversion rights as follows (the "Conversion Rights"):

         (a) RIGHT TO CONVERT. Each issued and outstanding share of Class A
Preferred Stock shall be convertible, at the option of the holder thereof, at
any time and from time to time, into such number of fully paid and nonassessable
shares of Common Stock as is determined (i) with respect to the Class A Series 1
Preferred Stock, by dividing $2.00 by the Series 1 Conversion Price (as defined
below) in effect at the time of conversion, (ii) with respect to the Class A
Series


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2 Preferred Stock, by dividing $2.00 by the Series 2 Conversion Price (as
defined below) in effect at the time of conversion, (iii) with respect to the
Class A Series 3 Preferred Stock, by dividing $2.00 by the Series 3 Conversion
Price (as defined below) in effect at the time of conversion, (iv) with respect
to the Class A Series 4 Preferred Stock, by dividing $3.13 by the Series 4
Conversion Price (as defined below) in effect at the time of conversion, and (v)
with respect to Class A Series 5 Preferred Stock, by dividing $5.45 by the
Series 5 Conversion Price (as defined below) in effect at the time of
conversion. The price at which shares of Common Stock shall be deliverable upon
conversion of Class A Preferred Stock without the payment of additional
consideration by the holder thereof (in each case, the "Conversion Price") shall
be (after giving effect to the 0.652-for-1 reverse stock split effected by an
amendment to the Certificate of Incorporation filed on or before March 23, 1998)
(i) $3.067485 per share (the "Series 1 Conversion Price") for Class A Series 1
Preferred Stock, (ii) $3.067485 per share (the "Series 2 Conversion Price") for
the Class A Series 2 Preferred Stock, (iii) $3.067485 per share (the "Series 3
Conversion Price") for the Class A Series 3 Preferred Stock, (iv) $4.800613 per
share (the "Series 4 Conversion Price") for the Class A Series 4 Preferred
Stock, (v) $5.45 per share (the "Series 5 Conversion Price") for the Class A
Series 5 Preferred Stock, and in each case shall be subject to adjustment as
provided below. Notwithstanding anything herein to the contrary, the shares of
Class A Series 5 Preferred Stock may only be converted hereunder after August
31, 1999.

         In the event of a liquidation, dissolution or winding up of the
Corporation, the Conversion Rights shall terminate at the close of business on
the business day preceding the date fixed for the payment of any amounts
distributable on liquidation to the holders of the Class A Preferred Stock.

         (b) FRACTIONAL SHARES. No fractional shares of Common Stock shall be
issued upon conversion of the Class A Preferred Stock. In lieu of any fractional
shares to which the holder would otherwise be entitled, the Corporation shall
pay cash equal to the product of such fraction multiplied by the market price of
one share of the Corporation's Common Stock on the Conversion Date, as such term
is defined in subsection 5(c)(i) below.

         (c)      MECHANICS OF CONVERSION.

                  (i) In order for a holder of the Class A Preferred Stock to
convert shares of the Class A Preferred Stock into shares of Common Stock, such
holder shall surrender the certificate or certificates for such shares of the
Class A Preferred Stock, at the office of the transfer agent for the Class A
Preferred Stock (or at the principal office of the Corporation if the
Corporation serves as its own transfer agent), together with written notice that
such holder elects to convert all or any number of the shares of the Class A
Preferred Stock represented by such certificate or certificates. Such notice
shall state such holder's name or the names of the nominees in which such holder
wishes the certificate or certificates for shares of Common Stock to be issued
and the number of shares, class and series (if any) of the Class A Preferred
Stock to be converted. If required by the Corporation, certificates surrendered
for conversion shall be endorsed or accompanied by a written instrument or
instruments of transfer, in form satisfactory to the Corporation, duly executed
by the registered holder or his or its attorney duly authorized in writing. The
date of receipt of such certificates and notice by the transfer agent (or by the
Corporation if the Corporation serves as its own transfer agent) shall be the
conversion date (the


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"Conversion Date"), and the conversion shall be deemed effective as of the close
of business on the Conversion Date. The Corporation shall, as soon as
practicable after the Conversion Date, issue and deliver at such office to such
holder of the Class A Preferred Stock, or to his or its nominees, a certificate
or certificates for the number of shares of Common Stock to which such holder
shall be entitled, together with cash in lieu of any fraction of a share.

                  (ii) The Corporation shall at all times when the Class A
Preferred Stock shall be outstanding, reserve and keep available out of its
authorized but unissued stock, for the purpose of effecting the conversion of
the Class A Preferred Stock, such number of its duly authorized shares of Common
Stock as shall from time to time be sufficient to effect the conversion of all
outstanding Class A Preferred Stock. Before taking any action which would cause
an adjustment reducing the Conversion Price below the then par value of the
shares of Common Stock issuable upon conversion of the Class A Preferred Stock,
the Corporation will take any corporate action which may, in the opinion of its
counsel, be necessary in order that the Corporation may validly and legally
issue fully paid and nonassessable shares of Common Stock at such adjusted
Conversion Price.

                  (iii) Upon any such conversion, no adjustment to the
Conversion Price shall be made for any declared and unpaid dividends on the
Class A Preferred Stock surrendered for conversion or on the Common Stock
delivered upon conversion of the Class A Preferred Stock.

                  (iv) All shares of the Class A Preferred Stock which shall
have been surrendered for conversion as herein provided shall no longer be
deemed to be outstanding and all rights with respect to such shares, including
the rights, if any, to receive notices and to vote, shall immediately cease and
terminate at the close of business on the Conversion Date, except only the right
of the holders thereof to receive shares of Common Stock in exchange therefor
and payment of all declared and unpaid dividends thereon. Any shares of the
Class A Preferred Stock so converted shall be retired and canceled and shall not
be reissued, and the Corporation may from time to time take such appropriate
action as may be necessary to reduce accordingly the authorized shares of Class
A Preferred Stock and the respective series of such shares.

         (d) ADJUSTMENTS TO CONVERSION PRICE FOR DILUTING ISSUES WITH RESPECT TO
THE CLASS A PREFERRED STOCK:

                  (i) SPECIAL DEFINITIONS. For purposes of this Subsection 5(d),
the following definitions shall apply:

                             (A) "OPTION" shall mean any outstanding rights,
options or warrants to subscribe for, purchase or otherwise acquire Common Stock
or Convertible Securities, excluding rights, warrants and options granted to
employees, consultants or scientific advisory board members of the Corporation
or any subsidiary thereof pursuant to an option plan or agreement adopted by the
Board of Directors with respect to up to 2,364,200 shares of Common Stock
(subject to appropriate adjustment for any further stock dividend, stock split,
combination or other similar recapitalization affecting such shares), or such
higher number as may be designated from time to time by the Board of Directors
and approved by the holders of a majority of the outstanding shares of Class A
Series 3 Preferred Stock and Class A Series 5 Preferred Stock, voting together
as a single Class.


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                             (B) "ORIGINAL ISSUE DATE" shall mean, as to a
series of Class A Preferred Stock, the date on which the first share of such
series was first issued.

                             (C) "CONVERTIBLE SECURITIES" shall mean any
evidences of indebtedness, shares (other than Class A Series 1 Preferred Stock,
Class A Series 2 Preferred Stock, Class A Series 3 Preferred Stock, Class A
Series 4 Preferred Stock and Class A Series 5 Preferred Stock) or other
securities directly or indirectly convertible into or exchangeable for Common
Stock.

                             (D) "ADDITIONAL SHARES OF COMMON STOCK" when used
with respect to a series of Class A Preferred Stock shall mean all shares of
Common Stock issued (or, pursuant to Subsection 5(d)(iii) below, deemed to be
issued) by the Corporation after the Original Issue Date of such series, other
than shares of Common Stock issued or issuable:

                  (I)      upon conversion of shares of Class A Preferred Stock;

                  (II)     as a dividend or distribution on Class A Preferred
                           Stock;

                  (III)    by reason of a dividend, stock split, split-up or
                           other distribution on shares of Common Stock;

                  (IV)     upon the exercise of options excluded from the
                           definition of "Option" in Subsection 5(d)(i)(A);

                  (V)      in connection with the licensing or acquisition by
                           the Corporation of technology or intellectual
                           property;

                  (VI)     upon the exercise of options or warrants with respect
                           to up to 200,000 shares of Common Stock in the
                           aggregate issued or issuable in exchange for options
                           or warrants to purchase shares of the common stock,
                           no par value per share, of Protein Engineering
                           Corporation issued on or before the Original Issue
                           Date of the Class A Series 3 Preferred Stock; or

                  (VII)    the conversion of certain demand promissory notes of
                           the Corporation issued on or before the Original
                           Issue Date of the Class A Series 3 Preferred Stock
                           which shares shall not exceed 95,000 shares in the
                           aggregate.

                  (E) "COMMON STOCK DEEMED OUTSTANDING" means, at any given
time, the number of shares of Common Stock actually outstanding at such time,
plus the number of shares of Common Stock issuable at such time upon conversion
of the Class A Preferred Stock or other Convertible Securities then outstanding,
plus the number of shares of Common Stock issuable at any time upon the exercise
of all then outstanding options, warrants or other rights to purchase Common
Stock (whether or not excluded from the definition of the term "Option", in
Subsection 5(d)(i)(A)).


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<PAGE>

                  (ii) NO ADJUSTMENT OF CONVERSION PRICES. No adjustment in the
number of shares of Common Stock into which the Class A Series 1 Preferred Stock
are convertible shall be made, by adjustment in the applicable Conversion Price
thereof or otherwise, if prior to such adjustment the Corporation receives
written notice from the holders of at least 50.1% of the outstanding shares of
Class A Series 1 Preferred Stock agreeing that no such adjustment shall be made.
No adjustment in the number of shares of Common Stock into which the Class A
Series 2 Preferred Stock are convertible shall be made, by adjustment in the
applicable Conversion Price thereof or otherwise, if prior to such adjustment
the Corporation receives written notice from the holders of at least 50.1% of
the outstanding shares of Class A Series 2 Preferred Stock agreeing that no such
adjustment shall be made. No adjustment in the number of shares of Common Stock
into which the Class A Series 3 Preferred Stock are convertible shall be made,
by adjustment in the applicable Conversion Price or otherwise, if prior to such
adjustment, the Corporation receives written notice from the holders of at least
50.1% of the outstanding shares of Class A Series 3 Preferred Stock agreeing
that no such adjustment shall be made. No adjustment in the number of shares of
Common Stock into which the Class A Series 4 Preferred Stock are convertible
shall be made, by adjustment in the applicable Conversion Price or otherwise, if
prior to such adjustment the Corporation receives written notice from the
holders of at least 50.1% of the outstanding shares of Class A Series 4
Preferred Stock agreeing that no such adjustment shall be made. No adjustment in
the number of shares of Common Stock into which the Class A Series 5 Preferred
Stock are convertible shall be made, by adjustment in the applicable Conversion
Price thereof or otherwise, if prior to such adjustment the Corporation receives
written notice from the holders of at least 50.1% of the outstanding shares of
Class A Series 5 Preferred Stock agreeing that no such adjustment shall be made.
Notwithstanding the foregoing, no adjustment in the number of shares of Common
Stock into which the Class A Series 1 Preferred Stock, Class A Series 2
Preferred Stock and the Class A Series 3 Preferred Stock are convertible shall
be made, by adjustment in the applicable Conversion Price thereof or otherwise,
if (i) such adjustment would be the same for all such series of Class A
Preferred Stock and (ii) prior to such adjustment, the Corporation receives
written notice from the holders of at least 50.1% of the aggregate number of
outstanding shares of all such series of Class A Preferred Stock agreeing that
no such adjustment shall be made. The Corporation shall provide written notice
of any such agreement with respect to the Class A Preferred Stock or any series
of the Class A Preferred Stock, as the case may be, to all registered holders of
such class or series. In addition, no adjustment shall be made in the applicable
Conversion Price as the result of the issuance of Additional Shares of Common
Stock or otherwise, unless the consideration per share (determined pursuant to
Subsection 5(d)(v)) for an Additional Share of Common Stock issued or deemed to
be issued by the Corporation is less than the applicable Conversion Price in
effect on the date of, and immediately prior to, the issue of such Additional
Shares of Common Stock.

                  (iii) ISSUE OF OPTIONS AND CONVERTIBLE SECURITIES DEEMED ISSUE
OF ADDITIONAL SHARES OF COMMON Stock. If the Corporation at any time or from
time to time after the Original Issue Date shall issue any Options or
Convertible Securities, then the maximum number of shares of Common Stock (as
set forth in the instrument relating thereto without regard to any provision
contained therein for a subsequent adjustment of such number) issuable upon the
exercise of such Options or, in the case of Convertible Securities and Options
therefor, the conversion or exchange of such Convertible Securities, shall be
deemed to be Additional Shares of Common Stock issued as of the time of such
issue or, in case such a record date shall have been fixed, as of the close of
business on such record date, provided that Additional Shares of


                                       10
<PAGE>

Common Stock shall not be deemed to have been issued unless the consideration
per share (determined pursuant to Subsection 5(d)(v) hereof) of such
Additional Shares of Common Stock would be less than the applicable
Conversion Price in effect on the date of and immediately prior to such
issue, or such record date, as the case may be, and provided further that in
any such case in which Additional Shares of Common Stock are deemed to be
issued:

                             (A) no further adjustment in the Conversion Price
shall be made upon the subsequent issue of Convertible Securities or shares of
Common Stock upon the exercise of such Options or conversion or exchange of such
Convertible Securities;

                             (B) if such Options or Convertible Securities by
their terms provide, with the passage of time or otherwise, for any increase in
the consideration payable to the Corporation, or decrease in the number of
shares of Common Stock issuable, upon the exercise, conversion or exchange
thereof, the Conversion Prices computed upon the original issue thereof (or upon
the occurrence of a record date with respect thereto), and any subsequent
adjustments based thereon, shall, upon any such increase or decrease becoming
effective, be recomputed to reflect such increase or decrease insofar as it
affects such Options or the rights of conversion or exchange under such
Convertible Securities;

                             (C) no recomputation pursuant to clause (B) above
shall have the effect of increasing the Conversion Price to an amount which
exceeds the lower of (i) the applicable Conversion Price on the original
adjustment date, or (ii) the Conversion Price that would have resulted from any
issuance of Additional Shares of Common Stock between the original adjustment
date and such recomputation date; and

                             (D) upon the expiration or termination of any
unexercised Option, the Conversion Price shall be readjusted, and the Additional
Shares of Common Stock deemed issued as the result of the original issue of such
Option shall not be deemed issued for the purpose of such readjustment.

                  (iv) ADJUSTMENT OF CONVERSION PRICE UPON ISSUANCE OF
ADDITIONAL SHARES OF COMMON STOCK. In the event the Corporation shall issue
Additional Shares of Common Stock (including Additional Shares of Common Stock
deemed to be issued pursuant to Subsection 5(d)(iii)), without consideration or
for a consideration per share (determined pursuant to Subsection 5(d)(v) hereof)
less than the applicable Conversion Price for any series of Class A Preferred
Stock in effect on the date of and immediately prior to such issue, then
forthwith upon such issue any such Conversion Price will be reduced to a
Conversion Price determined in accordance with the following formula:

         New Conversion Price =      P1Q1 + P2Q2
                                     -----------
                                       Ql +  Q2

         where:

         Pl =     Conversion Price in effect immediately prior to such issue;

         Ql       = Number of shares of Common Stock Deemed Outstanding (as
                  defined in Subsection 5(d)(i)(E)) immediately prior to such
                  issue;


                                       11
<PAGE>

         P2 =     Average price per share received by the Corporation upon
                  such issue; and

         Q2 =     Number of shares of Common Stock issued, or deemed to have
                  been issued, in the subject transaction;

PROVIDED that in computing each Conversion Price the result shall be rounded to
the nearest hundredth of a cent.

                  (v) DETERMINATION OF CONSIDERATION. For purposes of this
Subsection 5(d), the consideration received by the Corporation for the issue of
any Additional Shares of Common Stock shall be computed as follows:

                             (A) CASH AND PROPERTY: Such consideration shall:

                                     (I) insofar as it consists of cash, be
computed at the aggregate of cash received by the Corporation, excluding amounts
paid or payable for accrued interest or accrued dividends, after deducting any
expenses of the Corporation in issuing Additional Shares;

                                     (II) insofar as it consists of property
other than cash, be computed at the fair market value thereof at the time of
such issue, as determined in good faith by the Board of Directors; and

                                     (III) insofar as it consists of securities,
be computed at the current market price, which shall be deemed to be the average
of the daily closing price for the 20 consecutive business days ending on the
fifth (5th) business day before the day of issuance in question; and

                                     (IV) in the event Additional Shares of
Common Stock are issued together with other shares or securities or other assets
of the Corporation for consideration which covers both, be the proportion of
such consideration so received, computed as provided in clauses (I) through
(III) above, as determined in good faith by the Board of Directors.

                             (B) OPTIONS AND CONVERTIBLE SECURITIES. The
consideration per share received by the Corporation for Additional Shares of
Common Stock deemed to have been issued pursuant to Subsection 5(d)(iii),
relating to Options and Convertible Securities, shall be determined by dividing

                                     (x) the total amount, if any, received or
receivable by the Corporation as consideration for the issue of such Options or
Convertible Securities, plus the minimum aggregate amount of additional
consideration (as set forth in the instruments relating thereto, without regard
to any provision contained therein for a subsequent adjustment of such
consideration) payable to the Corporation upon the exercise of such Options or
the conversion or exchange of such Convertible Securities, or in the case of
Options for Convertible Securities, the exercise of such Options for Convertible
Securities and the conversion or exchange of such Convertible Securities, by


                                       12
<PAGE>

                                     (y) the maximum number of shares of Common
Stock (as set forth in the instruments relating thereto, without regard to any
provision contained therein for a subsequent adjustment of such number) issuable
upon the exercise of such Options or the conversion or exchange of such
Convertible Securities.

         (e) ADJUSTMENT FOR STOCK SPLITS, STOCK DIVIDENDS, SUBDIVISIONS,
COMBINATIONS OR CONSOLIDATION OF COMMON STOCK. In the event the outstanding
shares of Common Stock shall be split, subdivided, combined or consolidated, by
reclassification or otherwise, into a greater or lesser number of shares of
Common Stock, and in the event that the Corporation shall issue shares of Common
Stock by way of a stock dividend or other distribution to the holders of Common
Stock, the number of shares of Common Stock into which each issued and
outstanding share of each series of Class A Preferred Stock shall be convertible
immediately prior to such split, subdivision, stock dividend, combination or
consolidation shall, concurrently with the effectiveness of such split,
subdivision, stock dividend, combination or consolidation, be increased or
decreased proportionately.

         (f) CERTIFICATE AS TO ADJUSTMENTS. Upon the occurrence of each
adjustment or readjustment of the applicable Conversion Price of shares of
Common Stock into which each issued and outstanding share of any series of Class
A Preferred Stock shall be convertible pursuant to this Section 5, the
Corporation at its expense shall promptly compute such adjustment or
readjustment in accordance with the terms hereof and furnish to each holder of
such series of Class A Preferred Stock a certificate setting forth such
adjustment or readjustment and showing in detail the facts upon which such
adjustment or readjustment is based. The Corporation shall, upon the written
request at any time of any holder of each series of Class A Preferred Stock,
furnish or cause to be furnished to such holder a similar certificate setting
forth (i) such adjustments and readjustments, (ii) the Conversion Price of
shares of Common Stock into which each issued and outstanding share of such
series of Class A Preferred Stock shall be convertible, and (iii) the number of
shares of Common Stock and the amount, if any, of other property which then
would be received upon the conversion of any class or series of Class A
Preferred Stock of which such holder is the record owner.

         (g) MERGER OR SALE OF ASSETS. If at any time or from time to time there
shall be a merger or consolidation of the Corporation with or into another
corporation, or the sale of all or substantially all of the Corporation's assets
to any other person, then, as a part of such merger, consolidation or sale,
provision shall be made so that the holders of each series of Class A Preferred
Stock then outstanding shall thereafter be entitled to receive upon conversion
of such series of Class A Preferred Stock the number of shares of stock or other
securities or property of the Corporation, or of the successor corporation
resulting from such merger, consolidation or sale, to which a holder of Common
Stock issuable upon conversion would have been entitled on such merger,
consolidation, or sale. Notwithstanding the above, in the case of a merger,
consolidation, or sale of substantially all of the assets of the Corporation
prior to August 31, 1999 pursuant to which the holders of the Corporation's
capital stock immediately before such transaction hold less than 50% of the
capital stock of the successor corporation resulting from such transaction, then
at the option of the holders of no less than 50.1% of the Class A Series 5
Preferred Stock, all holders of Class A Series 5 Preferred Stock shall be
entitled to receive the number of shares of stock or other securities or
property of the Corporation, or of the successor corporation resulting from such
merger, consolidation or sale, to which each holder would have


                                       13
<PAGE>

been entitled to receive as if all of such Class A Series 5 Preferred Stock had
been converted into Common Stockimmediately prior to such merger, consolidation
or sale.

         (h)      NOTICE OF RECORD DATE.  In the event:

                  (i) that the Corporation declares a dividend (or any other
distribution) on its Common Stock payable in Common Stock or other securities of
the Corporation;

                  (ii) that the Corporation subdivides or combines its
outstanding shares of Common Stock;

                  (iii) of any reclassification of the Common Stock of the
Corporation (other than a subdivision or combination of its outstanding shares
of Common Stock or a stock dividend or stock distribution thereon), or of any
consolidation or merger of the Corporation into or with another corporation, or
of the sale of all or substantially all of the assets of the Corporation; or

                  (iv) of the involuntary or voluntary dissolution, liquidation
or winding up of the Corporation; then the Corporation shall cause to be filed
at its principal office or at the office of the transfer agent of the Class A
Preferred Stock, and shall cause to be mailed to the holders of the Class A
Preferred Stock at their last addresses as shown on the records of the
Corporation or such transfer agent, at least ten days prior to the record date
specified in (A) below or twenty days before the date specified in (B) below, a
notice stating

                             (A) the record date of such dividend, distribution,
subdivision or combination, or, if a record is not to be taken, the date as of
which the holders of Common Stock of record to be entitled to such dividend,
distribution, subdivision or combination are to be determined, or

                             (B) the date on which such reclassification,
consolidation, merger, sale, dissolution, liquidation or winding up is expected
to become effective, and the date as of which it is expected that holders of
Common Stock of record shall be entitled to exchange their shares of Common
Stock for securities or other property deliverable upon such reclassification,
consolidation, merger, sale, dissolution or winding up, or

                             (C) the events constituting a diluting issue or
issuance of Additional Shares, the consideration per share, the New Conversion
Price and the calculation thereof, and any additional information which would be
relevant to holders of Class A Series 5 Preferred Stock in making an informed
election under Section 5(d)(ii).

         (i)      MISCELLANEOUS CONVERSION PROVISIONS.

                  (i) If a state of facts shall occur that, without being
specifically controlled by the provisions of this Section 5, would not fairly
protect the conversion rights of the holders of the Class A Preferred Stock in
accordance with the essential intent and principles of such provisions, then the
Board of Directors shall make an adjustment in the application of such


                                       14
<PAGE>

provisions, in accordance with such essential intent and principles, so as to
protect such conversion rights.

                  (ii) The Corporation shall pay all documentary, stamp or other
transactional taxes attributable to the insurance or delivery of shares of
capital stock of the Corporation upon conversion of any shares of Class A
Preferred Stock; provided, however, that the Corporation shall not be required
to pay any taxes which may be payable in respect of any transfer involved in the
issuance or delivery of any certificate for such shares in a name other than
that of the Class A Preferred Stock holder in respect of which such shares of
Class A Preferred Stock are being issued.

                  (iii) In the event that a holder of Class A Preferred Stock
transfers such Class A Preferred Stock (the "Transferred Stock") to any third
party, no adjustment to the Conversion Price of such Transferred Stock shall be
made as a result of such transfer and the Conversation Price in effect with
respect to such Transferred Stock at the time of such transfer shall apply to
such third party with respect to such shares of Transferred Stock.

                  (iv) All certificates representing shares of Class A Preferred
Stock shall have affixed thereto a legend in substantially the following form:
"The shares represented by this certificate are convertible into shares of
Common Stock at a rate which may vary among different stockholders of the
Corporation. Information concerning the conversion rate applicable to the shares
represented by this certificate may be obtained from the Secretary of the
Corporation."

                  (v) Upon conversion of only a portion of the number of shares
covered by a Class A Preferred Stock Certificate, the Corporation shall issue
and deliver to or upon the written order of the holder of such Class A Preferred
Stock Certificate, at the expense of the Corporation, a new certificate covering
the number of shares of the Class A Stock representing the unconverted portion
of the Class A Preferred Stock Certificate, which new certificate shall entitle
the holder thereof to all the rights, powers and privileges of a holder of such
shares.

                  (vi) All shares of Common Stock which may be issued in
connection with the conversion provisions set forth herein will, upon issuance
by the Corporation, be validly issued, fully paid and nonassessable, not subject
to any preemptive or similar rights and free from all taxes, liens or charges
with respect thereto created or imposed by the Corporation.

         6.       AUTOMATIC CONVERSION.

         (a) All outstanding shares of the Class A Preferred Stock shall be
deemed automatically converted into the number of shares of Common Stock into
which each issued and outstanding share of Class A Preferred Stock shall be
convertible pursuant to Section 5 of this Part 4 upon the closing of a fully
underwritten, firm commitment public offering pursuant to an effective
registration statement on Form S-1 or the then equivalent form covering the
offer and sale by the Corporation of its Common Stock under the Securities Act
of 1933, as amended ("Securities Act"), where the aggregate net proceeds to the
Corporation (after deduction of underwriting discounts and commissions) are not
less than $20,000,000 and the per share sales price of such securities equals or
exceeds (i) $10.00 per share if the closing of such offering


                                       15
<PAGE>

occurs prior to August 31, 1999; or (ii) $15.00 per share if the closing occurs
thereafter (each such amount to be equitably adjusted upon the occurrence of any
stock split, stock dividend, combination, reclassification or other similar
event) (an "Automatic Conversion Event"). On or after the date of occurrence of
an Automatic Conversion Event, the Corporation shall promptly provide notice by
mail, postage prepaid, of the occurrence of such event to each holder of record
of shares of the Class A Preferred Stock and within 10 days after receipt of
such notice, each holder of record of shares of the Class A Preferred Stock
shall surrender such holder's certificates evidencing such shares at the
principal office of the Corporation or at such other place as the Corporation
shall designate, and shall thereupon be entitled to receive certificates
evidencing the number of shares of Common Stock into which such shares of the
Class A Preferred Stock are converted and cash as provided in subsection 5(b) in
respect of any fraction of a share of Common Stock otherwise issuable upon such
conversion. On the date of the occurrence of an Automatic Conversion Event, each
holder of record of shares of the Class A Preferred Stock shall be deemed to be
the holder of record of the Common Stock issuable upon such conversion,
notwithstanding that the certificates representing such shares of the Class A
Preferred Stock shall not have been surrendered at the office of the
Corporation, that notice from the Corporation shall not have been received by
any holder of record of shares of the Class A Preferred Stock, or that the
certificates evidencing such shares of Common Stock shall not then be actually
delivered to such holder. Notwithstanding anything herein to the contrary, the
shares of Class A Series 5 Preferred Stock may only be converted hereunder after
August 31, 1999.

         (b) All certificates evidencing shares of the Class A Preferred Stock
which are required to be surrendered for conversion in accordance with the
provisions hereof shall, from and after the date such certificates are so
required to be surrendered, be deemed to have been retired and canceled and the
shares of the Class A Preferred Stock represented thereby converted into Common
Stock for all purposes, notwithstanding the failure of the holder or holders
thereof to surrender such certificates on or prior to such date. The Corporation
may thereafter take such appropriate action as may be necessary to reduce the
authorized Class A Preferred Stock accordingly.

         7.       RESTRICTIONS AND LIMITATIONS.

         (a) CERTAIN REQUIRED APPROVALS BY CLASS A PREFERRED STOCK. Except as
expressly provided herein or as required by law, so long as any shares of the
Class A Preferred Stock remain outstanding, the Corporation shall not, and shall
not permit any subsidiary (which shall mean any corporation or trust of which
the Corporation directly or indirectly owns at the time a majority of the
outstanding shares of such corporation or trust entitled to vote in the election
of directors) to, without the approval by vote or written consent by the holders
of at least 50.1% of the then outstanding shares of the Class A Preferred Stock,
each share of Class A Preferred Stock to be entitled to one vote in each
instance:

                  (i) Redeem, purchase or otherwise acquire for value any share
or shares of Class A Preferred Stock;

                  (ii) Authorize or issue, or obligate itself to authorize or
issue, any other equity security (or any debt security convertible into an
equity security) ranking on parity with or senior to the Class A Preferred Stock
as to dividends or liquidation preferences;


                                       16
<PAGE>

                  (iii) Increase or decrease (other than by conversion as
permitted hereby) the total number of authorized shares of Class A Preferred
Stock; or

                  (iv) Effect any sale, lease, assignment, transfer or other
conveyance of all or substantially all of the assets or capital stock of the
Corporation or any subsidiary thereof, or any consolidation or merger involving
the Corporation or any subsidiary thereof, or any reclassification or other
change of stock, or any recapitalization or any dissolution, liquidation or
winding up of the Corporation.

         (b) CERTAIN AMENDMENTS OF CERTIFICATE OF INCORPORATION REQUIRING
APPROVAL BY CLASS A PREFERRED STOCK. The Corporation shall not amend its
Certificate of Incorporation without the approval, by vote or written consent,
by the holders of at least 50.1% of the then outstanding shares of Class A
Preferred Stock, each share of Class A Preferred Stock to be entitled to one
vote in each instance, if such amendment would adversely affect any of the
rights, preferences, privileges of or limitations provided for herein for the
benefit of any shares of Class A Preferred Stock. Without limiting the
generality of the next preceding sentence, the Corporation will not amend its
Certificate of Incorporation without the approval by the holders of at least
50.1% of the then outstanding shares of Class A Preferred Stock if such
amendment would:

                  (i) Change the dividend rights of the holders of Class A
Preferred Stock, or change the relative seniority of the dividend rights of the
holders of Class A Preferred Stock in relation to the holders of any other
capital stock of the Corporation;

                  (ii) Reduce the amount payable to the holders of Class A
Preferred Stock upon the voluntary or involuntary liquidation, dissolution or
winding up of the Corporation, or change the relative seniority of the
liquidation preferences of the holders of Class A Preferred Stock in relation to
the rights upon liquidation of the holders of any other capital stock of the
Corporation;

                  (iii) Change or modify the conversion rights of the holders of
Class A Preferred Stock provided for in Sections 5 and 6 of this Part 5;

                  (iv) Change or modify the rights, preferences, privileges or
limitations, if any, provided for herein relating to redemption of Class A
Preferred Stock; or

                  (v) Change any of the rights, preferences, privileges or
limitations provided for herein relating to the voting rights of the holders of
Class A Preferred Stock, other than the election of Class A directors by less
than all series of Class A Preferred Stock.

         Notwithstanding the foregoing, the Corporation will not amend its
Certificate of Incorporation to change any of the rights, preferences,
privileges or limitations provided for herein relating to the election of the
Series 3 Director, Series 4 Director or Series 5 Director without the approval
of the holders of at least 50.1% of the then outstanding shares of the Class A
Series 3 Preferred Stock, Class A Series 4 Preferred Stock or Class A Series 5
Preferred Stock entitled to elect such director, voting separately as a class.
Furthermore, the Corporation shall not amend its Certificate of Incorporation if
such amendment would in any manner alter, change or modify, the designations,
powers, preferences, rights, privileges, qualifications, limitations or


                                       17
<PAGE>

restrictions of the Class A Series 5 Preferred Stock without the approval of the
holders of at least 50.1% of the then outstanding shares of the Class A Series 5
Preferred Stock.

         8.       TRANSFER OF SHARES.

                  Nothing in this Restated Certificate of Incorporation shall be
deemed to prevent a transfer of Common Stock or Class A Preferred Stock to: (i)
a person or entity controlling, controlled by or under common control with the
holder of Class A Preferred Stock, (ii) a partner, limited partner, member or
shareholder of holder of Class A Preferred Stock, or (iii) any other holder of
Common Stock or Class A Preferred Stock, to the extent that such transfer would
not be in violation of federal or state securities laws.

FIFTH:  The Corporation is to have perpetual existence.

SIXTH: The Board of Directors is expressly authorized to exercise all powers
granted to the directors by law except insofar as such powers are limited or
denied herein or in the by-laws of the Corporation. In furtherance of such
powers, the Board of Directors shall have the right to make, alter or repeal the
by-laws of the Corporation.

SEVENTH: Meetings of stockholders may be held within or without the State of
Delaware, as the by-laws may provide. The books of the Corporation may be kept
outside the State of Delaware at such place or places as may be designated from
time to time by the Board of Directors or in the by-laws of the Corporation.
Elections of directors need not be by written ballot unless the by-laws of the
Corporation shall so provide.

EIGHTH: The Corporation shall, to the fullest extent permitted by Section 145 of
the General Corporation Law of the State of Delaware, as that section may be
amended and supplemented from time to time, indemnify any and all persons whom
it shall have power under that section to indemnify against any expenses,
liabilities or other matters referred to in or covered by that section. The
indemnification provided for herein shall not be deemed exclusive of any other
rights to which those seeking indemnification may be entitled under any by-law,
agreement, vote of stockholders or disinterested directors or otherwise, both as
to action in their official capacities and as to action in another capacity
while holding such office, and shall continue as to a person who has ceased to
be a director, officer, employee or agent and shall inure to the benefit of the
heirs, executors and administrators of such a person.

NINTH: No director shall be personally liable to the Corporation or its
stockholders for monetary damages for any breach of fiduciary duty by such
director as a director. Notwithstanding the foregoing sentence, a director shall
be liable to the extent provided by applicable law (i) for breach of the
director's duty of loyalty to the Corporation or its stockholders, (ii) for acts
or omissions not in good faith or which involve intentional misconduct or a
knowing violation of law, (iii) pursuant to Section 174 of the Delaware General
Corporation Law or (iv) for any transaction from which the director derived an
improper personal benefit. If the Delaware General Corporation Law is hereafter
amended to authorize a further limitation or elimination of the liability of
directors or officers, then the liability of a director or officer of the
Corporation shall, in addition to the limitation on personal liability provided
herein, be limited or eliminated to the fullest extent permitted by the Delaware
General Corporation Law, as from


                                       18
<PAGE>

time to time amended. No amendment to or repeal of this Article Ninth shall
apply to or have any effect on the liability or alleged liability of any
director or officer of the Corporation for or with respect to any acts or
omissions of such director or officer occurring prior to such amendment or
repeal.

TENTH: The Corporation reserves the right to amend, alter, change or repeal any
provision contained in this Restated Certificate of Incorporation, in accordance
with the provisions and in the manner now or hereafter prescribed by statute,
and all rights conferred upon stockholders herein are granted subject to this
reservation.

         Signed and attested this 31st day of August, 1998.


                               /s/ Henry E. Blair
                                   --------------------------------
                                   Henry E. Blair
                                   President


                                       19
<PAGE>

                            CERTIFICATE OF AMENDMENT
                                       OF
                      RESTATED CERTIFICATE OF INCORPORATION
                                       OF
                                   DYAX CORP.
                     Pursuant to Section 242 of the General
                    CORPORATION LAW OF THE STATE OF DELAWARE

         DYAX CORP. (hereinafter called the "Corporation"), a corporation
existing under and by virtue of the General Corporation Law of the State of
Delaware (the "Delaware Law"), does hereby certify that (a) pursuant to an
Action by Unanimous Written Consent of Directors dated October 2, 1998, the
Board of Directors duly adopted resolutions pursuant to Section 242 of the
Delaware Law proposing certain amendments to the Restated Certificate of
Incorporation of the Corporation, as amended, and declaring said amendments to
be advisable; and (b) that in lieu of a meeting and vote of the Stockholders,
the Stockholders of the Corporation have given their written consent to said
amendments in accordance with the provisions of Section 228 of the Delaware Law
and a notice of such action has been sent to stockholders who did not execute
the Written Consent.

         Pursuant to the foregoing resolutions:
         1. The first sentence of Part 1 of Article FOURTH of the Corporation's
Restated Certificate of Incorporation, as amended, be and hereby is deleted and
the following sentence is inserted in lieu thereof: "The total number of shares
of all classes of stock which the Corporation shall have authority to issue is
thirty-five million three hundred twelve thousand three hundred ninety-one
(35,312,391) shares, of which twenty million (20,000,000) shares, par value
$0.01 per share, are to be of a class designated "Common Stock", and fifteen
million three hundred twelve thousand three hundred ninety-one (15,312,391)
shares, par value $0.01 per share, are to be of a class designated "Class A
Preferred Stock"."

         2. The first sentence of Section 1 of Part 5 of Article FOURTH of the
Corporation's Restated Certificate of Incorporation, as amended, be and hereby
is deleted and the following sentence is inserted in lieu thereof:

"One million nine hundred forty-four thousand five hundred (1,944,500) shares of
Class A Preferred Stock are hereby designated as "Class A Series 1 Preferred
Stock", seven hundred four thousand (704,000) shares of Class A Preferred Stock
are hereby designated as "Class A Series 2 Preferred Stock ", two million
(2,000,000) shares of Class A Preferred Stock are hereby designated as "Class A
Series 3 Preferred Stock", four million seven hundred ninety-two thousand three
hundred thirty-two (4,792,332) shares of Class A Preferred Stock are hereby
designated "Class A Series 4 Preferred Stock", and five million eight hundred
seventy-one thousand five hundred fifty-nine (5,871,559) shares of Class A
Preferred Stock are hereby designated "Class A Series 5 Preferred Stock"."


                                       20
<PAGE>

         IN WITNESS WHEREOF, said Corporation has caused this Certificate to be
signed by its President this 31st day of October, 1998.

                                  DYAX CORP.


                                  By: /s/ Henry E. Blair
                                      --------------------------------
                                      Henry E. Blair
                                      President and Chief Executive Officer


                                       21

<PAGE>

                            CERTIFICATE OF AMENDMENT

                                       OF

                      RESTATED CERTIFICATE OF INCORPORATION

                                       OF

                                   DYAX CORP.



                     Pursuant to Section 242 of the General
                    CORPORATION LAW OF THE STATE OF DELAWARE


         DYAX CORP. (hereinafter called the "Corporation"), a corporation
existing under and by virtue of the General Corporation Law of the State of
Delaware (the "Delaware Law"), does hereby certify that (a) pursuant to an
Action by Unanimous Written Consent of Directors dated August 2, 2000, the Board
of Directors duly adopted resolutions pursuant to Section 242 of the Delaware
Law proposing certain amendments to the Restated Certificate of Incorporation of
the Corporation, as amended, and declaring said amendments to be advisable; and
(b) that in lieu of a meeting and vote of the Stockholders, the Stockholders of
the Corporation have given their written consent to said amendments in
accordance with the provisions of Section 228 of the Delaware Law and a notice
of such action has been sent to stockholders who did not execute the Written
Consent.

         Pursuant to the foregoing resolutions:

         The words "August 31, 1999" in clause (i) of the first sentence of
         Section 6(a) of Part 5 of Article FOURTH of the Corporation's Restated
         Certificate of Incorporation, as amended, be and hereby are deleted and
         the words "December 31, 2000" are inserted in lieu thereof.

                                      22

<PAGE>


         IN WITNESS  WHEREOF,  said Corporation has caused this Certificate to
be signed by its President this 11th day of August, 2000.

                                                     DYAX CORP.



                           By:    _/S/ HENRY E. BLAIR
                                  Henry E. Blair
                                  President and Chief Executive Officer

                                      23