RESTATED CERTIFICATE OF
 
                                  INCORPORATION
 
                                       OF
 
                     DARWIN PROFESSIONAL UNDERWRITERS, INC.
 
                                   ----------
 
                                    DELAWARE
 
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                      RESTATED CERTIFICATE OF INCORPORATION
                                       OF
                     DARWIN PROFESSIONAL UNDERWRITERS, INC.
 
     FIRST: The name of the Corporation is Darwin Professional Underwriters,
Inc.
 
     SECOND: The address of the Corporation's registered office in the State of
Delaware is Corporation Trust Center, 1209 Orange Street, in the City of
Wilmington, County of New Castle. The name of the Corporation's registered agent
at such address is The Corporation Trust Company.
 
     THIRD: The purpose of the Corporation is to engage in any lawful act or
activity for which corporations may be organized under the General Corporation
Law of the State of Delaware.
 
     FOURTH: The total number of shares of all classes of capital stock which
the Corporation shall have authority to issue is 60,000,000 shares, of which
50,000,000 shares shall be common stock, par value $0.01 per share (the "Common
Stock"), and 10,000,000 shares shall be preferred stock, par value $ 0.10 per
share (the "Preferred Stock").
 
          A. Preferred Stock. The Board of Directors is expressly authorized to
     provide for the issue of all or any shares of the Preferred Stock, in one
     or more series, and to fix for each such series such voting powers, full or
     limited, or no voting powers, and any other designations, preferences and
     relative, participating, optional or other special rights, and such
     qualifications, limitations or restrictions thereon, as shall be stated and
     expressed in the resolution or resolutions adopted by the Board of
     Directors providing for the issue of such series (a "Preferred Stock
     Designation") and as may be permitted by the General Corporation Law of the
     State of Delaware. The number of authorized shares of Preferred 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 the
     voting power of all of the then outstanding shares of the capital stock of
     the Corporation entitled to vote generally in the election of directors
     (the "Voting Stock"), voting together as a single class, without a separate
     vote of the holders of the Preferred Stock, or any series thereof, unless a
     vote of any such holders is required, pursuant to any Preferred Stock
     Designation.
 
          B. Common Stock. Except as otherwise required by law or as otherwise
     provided in any Preferred Stock Designation, the holders of the Common
     Stock shall exclusively possess all voting power, and each share of Common
     Stock shall have one vote; provided, however, that, except as otherwise
     required by law, holders of Common Stock shall not be entitled to vote on
     any amendment to this Certificate of Incorporation (including any Preferred
     Stock Designation) that
 
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     relates solely to the terms of one or more outstanding series of Preferred
     Stock if the holders of such affected series are entitled, either
     separately or together as a class with the holders of one or more other
     such series, to vote thereon pursuant to this Certificate of Incorporation
     (including any Preferred Stock Designation).
 
     FIFTH:
 
          A. Number, election and terms of directors. Subject to the rights of
     the holders of any series of Preferred Stock to elect additional directors
     under specified circumstances, the number of directors of the Corporation
     shall be fixed from time to time by action of a majority of the members of
     the Board of Directors then in office, but in no event shall such number of
     directors be less than three nor more than fifteen. Elections of members of
     the Board of Directors, other than those who may be elected by the holders
     of any series of Preferred Stock under specified circumstances, shall be
     held at the annual meeting of stockholders and each member of the Board of
     Directors shall hold office until such director's successor is elected and
     qualified, subject to such director's earlier death, resignation,
     disqualification or removal.
 
          B. Stockholder nomination of director candidates and introduction of
     business. Advance notice of stockholder nominations for the election of
     directors and of business to be brought by stockholders before any meeting
     of the stockholders of the Corporation shall be given in the manner
     provided in the Bylaws of the Corporation.
 
          C. Newly created directorships and vacancies. Subject to the rights of
     the holders of any series of Preferred Stock, and unless the Board of
     Directors otherwise determines, newly created directorships resulting from
     any increase in the authorized number of directors or any vacancies in the
     Board of Directors resulting from death, resignation, disqualification,
     removal from office or other cause may be filled only by a majority vote of
     the directors then in office, though less than a quorum, and any director
     so chosen shall hold office for a term expiring at the succeeding annual
     meeting of stockholders and until such director's successor shall have been
     duly elected and qualified. No decrease in the number of authorized
     directors constituting the entire Board of Directors shall shorten the term
     of any incumbent director.
 
          D. Removal. Subject to the rights of the holders of any series of
     Preferred Stock, any director, or the entire Board of Directors, may be
     removed, with or without cause, by the affirmative vote of the holders of a
     majority of the shares then entitled to vote at an election of directors;
     provided, however, that this Section D of Article FIFTH shall apply, in
     respect of the removal without cause of a director or directors elected by
     the holders of a class or series of stock pursuant to this Certificate of
     Incorporation or any Preferred Stock Designation, to the vote of the
     holders of the outstanding shares of that class or series and not to the
     vote of the outstanding shares as a whole.
 
 
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          SIXTH: In furtherance and not in limitation of the powers conferred by
     law, the Board of Directors is expressly authorized to make, alter, amend
     and repeal the Bylaws of the Corporation pursuant to a resolution adopted
     by the vote of a majority of the directors present at any regular or
     special meeting of the Board of Directors at which a quorum is present.
 
          SEVENTH: Subject to the rights of the holders of any series of
     Preferred Stock, (A) any action required or permitted to be taken by the
     stockholders of the Corporation must be effected at an annual or special
     meeting of stockholders of the Corporation and may not be effected by any
     consent in writing by such stockholders; provided, however, that this
     Section (A) of the first sentence of Article SEVENTH shall not apply to
     prohibit stockholder action by written consent in conformity with the
     provisions of Section 228 of the General Corporation Law of the State of
     Delaware, so long as Alleghany Corporation, a Delaware corporation, holds a
     majority of the Voting Stock of the Corporation and (B) special meetings of
     stockholders of the Corporation may be called only in the manner provided
     in this Article SEVENTH. At any time in the interval between regular
     meetings, special meetings of stockholders may be called only (x) by a
     majority of the Board of Directors or (y) upon the written request filed
     with the Secretary of the Corporation of holders of at least thirty percent
     (30%) of the outstanding shares of Voting Stock, to be held at such times
     and at such places within or without the State of Delaware as may be
     specified in the notices of such meetings. The notice of any special
     meeting shall state the purpose of the meeting and specify the action to be
     taken at said meeting and no business shall be transacted thereat except
     that specifically named in the notice.
 
          EIGHTH:
 
               A. A director of the Corporation shall not be personally liable
          to the Corporation or its stockholders for monetary damages for breach
          of fiduciary duty as a director, except for liability (i) for any
          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)
          under Section 174 of the General Corporation Law of the State of
          Delaware, or (iv) for any transaction from which the director derived
          an improper personal benefit. If the General Corporation Law of the
          State of Delaware is amended to authorize corporate action further
          eliminating or limiting the personal liability of directors, then the
          liability of a director of the Corporation shall be eliminated or
          limited to the fullest extent permitted by the General Corporation Law
          of the State of Delaware as so amended. Any repeal or modification of
          this Section (A) of this Article EIGHTH shall not adversely affect any
          right or protection of a director of the Corporation existing at the
          time of such repeal or modification.
 
               B. (1) Each person who was or is made a party or is threatened to
          be made a party to or is otherwise involved in any action, suit or
          proceeding, whether civil, criminal, administrative or investigative
          (hereinafter a "proceeding"), by reason of the fact that he or she is
          or was a director or an officer of the Corporation or is or was
          serving at the request of the Corporation as a director,
 
 
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          officer or trustee of another corporation or of a partnership, joint
          venture, trust or other enterprise, including service with respect to
          an employee benefit plan (hereinafter an "indemnitee"), whether the
          basis of such proceeding is alleged action in an official capacity as
          a director, officer or trustee or in any other capacity while serving
          as a director, officer or trustee, shall be indemnified and held
          harmless by the Corporation to the fullest extent permitted by the
          General Corporation Law of the State of Delaware, as the same exists
          or may hereafter be amended (but, in the case of any such amendment,
          only to the extent that such amendment permits the Corporation to
          provide broader indemnification rights than such law permitted the
          Corporation to provide prior to such amendment), against all expense,
          liability and loss (including attorneys' fees, judgments, fines, ERISA
          excise taxes or penalties and amounts paid in settlement) reasonably
          incurred or suffered by such indemnitee in connection therewith;
          provided, however, that, except as provided in subsection (3) of this
          Section (B) with respect to proceedings to enforce rights to
          indemnification, the Corporation shall indemnify any such indemnitee
          in connection with a proceeding (or part thereof) initiated by such
          indemnitee only if such proceeding (or part thereof) was authorized by
          the Board of Directors of the Corporation.
 
               (2) In addition to the right to indemnification conferred in
          subsection (1) of this Section (B), an indemnitee shall also have the
          right to be paid by the Corporation the expenses (including attorneys'
          fees) incurred in defending any such proceeding in advance of its
          final disposition (hereinafter an "advancement of expenses");
          provided, however, that, if the General Corporation Law of the State
          of Delaware requires, an advancement of expenses incurred by an
          indemnitee in his or her capacity as a director or officer (and not in
          any other capacity in which service was or is rendered by such
          indemnitee, including, without limitation, service to an employee
          benefit plan) shall be made only upon delivery to the Corporation of
          an undertaking (hereinafter an "undertaking"), by or on behalf of such
          indemnitee, to repay all amounts so advanced if it shall ultimately be
          determined by final judicial decision from which there is no further
          right to appeal (hereinafter a "final adjudication") that such
          indemnitee is not entitled to be indemnified for such expenses under
          subsection 2 of this Section (B) or otherwise.
 
               (3) If a claim under subsection (1) or (2) of this Section (B) is
          not paid in full by the Corporation within sixty (60) days after a
          written claim has been received by the Corporation, except in the case
          of a claim for an advancement of expenses, in which case the
          applicable period shall be twenty (20) days, the indemnitee may at any
          time thereafter bring suit against the Corporation to recover the
          unpaid amount of the claim. If successful in whole or in part in any
          such suit, or in a suit brought by the Corporation to recover an
          advancement of expenses pursuant to the terms of an undertaking, the
          indemnitee shall be entitled to be paid also the expense of
          prosecuting or defending such suit. In (i) any suit brought by the
          indemnitee to enforce a right to indemnification hereunder (but not in
          a suit brought by the indemnitee to enforce a right to an advancement
          of expenses) it shall be a defense that, and (ii) in any suit brought
          by the Corporation
 
 
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          to recover an advancement of expenses pursuant to the terms of an
          undertaking, the Corporation shall be entitled to recover such
          expenses upon a final adjudication that the indemnitee has not met any
          applicable standard for indemnification set forth in the General
          Corporation Law of the State of Delaware. Neither the failure of the
          Corporation (including its directors who are not parties to such
          action, a committee of such directors, independent legal counsel, or
          its stockholders) to have made a determination prior to the
          commencement of such suit that indemnification of the indemnitee is
          proper in the circumstances because the indemnitee has met the
          applicable standard of conduct set forth in the General Corporation
          Law of the State of Delaware, nor an actual determination by the
          Corporation (including its directors who are not parties to such
          action, a committee of such directors, independent legal counsel, or
          its stockholders) that the indemnitee has not met such applicable
          standard of conduct, shall create a presumption that the indemnitee
          has not met the applicable standard of conduct or, in the case of such
          a suit brought by the indemnitee, be a defense to such suit. In any
          suit brought by the indemnitee to enforce a right to indemnification
          or to an advancement of expenses hereunder, or brought by the
          Corporation to recover an advancement of expenses pursuant to the
          terms of an undertaking, the burden of proving that the indemnitee is
          not entitled to be indemnified, or to such advancement of expenses,
          under this Section (B) or otherwise shall be on the Corporation.
 
               (4) The rights to indemnification and to the advancement of
          expenses conferred in this Section (B) shall not be exclusive of any
          other right which any person may have or hereafter acquire under any
          statute, this Certificate of Incorporation, the Corporation's Bylaws,
          agreement, vote of stockholders or directors or otherwise.
 
               (5) The Corporation may maintain insurance, at its expense, to
          protect itself and any director, officer, employee or agent of the
          Corporation or another corporation, partnership, joint venture, trust
          or other enterprise against any expense, liability or loss, whether or
          not the Corporation would have the power to indemnify such person
          against such expense, liability or loss under the General Corporation
          Law of the State of Delaware.
 
               (6) The Corporation may, to the extent authorized from time to
          time by the Board of Directors, grant rights to indemnification and to
          the advancement of expenses to any employee or agent of the
          Corporation to the fullest extent of the provisions of this Article
          with respect to the indemnification and advancement of expenses of
          directors and officers of the Corporation.
 
               (7) The rights conferred upon indemnitees in this Section (B)
          shall be contract rights and such rights shall continue as to an
          indemnitee who has ceased to be a director, officer or trustee and
          shall inure to the benefit of the indemnitee's heirs, executors and
          administrators. Any amendment, alteration or repeal of this Section
          (B) that adversely affects any right of an indemnitee or its
          successors shall be prospective only and shall not limit or eliminate
          any such right with
 
 
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          respect to any proceeding involving any occurrence or alleged
          occurrence of any action or omission to act that took place prior to
          such amendment or repeal.
 
          NINTH:
 
               A. General. In recognition and anticipation (i) that the
          Corporation will not be wholly owned by Alleghany and its management,
          (ii) that directors, officers, employees and/or agents of Alleghany
          may serve as directors and/or officers of the Corporation, (iii) that
          Alleghany may engage in the same, similar or related lines of business
          as those in which the Corporation, directly or indirectly, may engage
          and/or other business activities that overlap with or compete with
          those in which the Corporation, directly or indirectly, may engage,
          (iv) that Alleghany may have an interest in the same areas of
          corporate opportunity as the Corporation and Affiliated Companies
          thereof, and (v) that, as a consequence of the foregoing, it is in the
          best interests of the Corporation that the respective rights and
          duties of the Corporation and of Alleghany, and the duties of any
          directors or officers of the Corporation who are also directors,
          officers, employees or agents of Alleghany, be determined and
          delineated in respect of any transactions between, or opportunities
          that may be suitable for both, the Corporation and Affiliated
          Companies thereof, on the one hand, and Alleghany, on the other hand,
          the provisions of this Article NINTH shall to the fullest extent
          permitted by law regulate and define the conduct of certain of the
          business and affairs of the Corporation and Affiliated Companies in
          relation to Alleghany and the conduct of certain affairs of the
          Corporation and Affiliated Companies as they may involve Alleghany and
          the officers, directors, employees and agents of Alleghany, and the
          power, rights, duties and liabilities of the Corporation and
          Affiliated Companies and the officers, directors and stockholders of
          the Corporation and Affiliated Companies in connection therewith. Any
          person purchasing or otherwise acquiring any shares of capital stock
          of the Corporation, or any interest therein, shall be deemed to have
          notice of and to have consented to the provisions of this Article
          NINTH.
 
               B. Business Activities. Except as otherwise agreed in writing
          between the Corporation and Alleghany, Alleghany shall to the fullest
          extent permitted by law have no duty to refrain from (i) engaging in
          the same or similar activities or lines of business as the Corporation
          or (ii) doing business with any client, customer or vendor of the
          Corporation.
 
               C. Corporate Opportunities.
 
               (1) In the event that Alleghany acquires knowledge of a potential
          transaction or matter which may be a corporate opportunity for both
          the Corporation and Alleghany, unless such opportunity was expressly
          offered to Alleghany in its capacity as a stockholder of the
          Corporation, the Corporation hereby renounces to the fullest extent
          permitted by law any interest or expectancy in such corporate
          opportunity such that (1) the Corporation waives any claim that such
          corporate opportunity should have been presented to the Corporation or
          any
 
 
                                        6
 
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          Affiliated Company thereof and (2) Alleghany shall have no duty to
          communicate or present such corporate opportunity to the Corporation.
 
               (2) In the event that a director or officer of the Corporation
          who is also a director, officer, employee or agent of Alleghany
          acquires knowledge of a potential transaction or matter which may be a
          corporate opportunity for both the Corporation and Alleghany, then
          unless such opportunity is expressly offered to such person solely in
          his or her capacity as a director or officer of the Corporation, the
          Corporation hereby renounces to the fullest extent permitted by law
          any interest or expectancy in such corporate opportunity such that (1)
          the Corporation waives any claim that such corporate opportunity
          should have been presented to the Corporation or any Affiliated
          Company thereof and (2) such officer or director shall have no duty to
          communicate or present such corporate opportunity to the Corporation.
 
               D. Certain Definitions. For purposes of this Article NINTH, (a)
          "Affiliated Company" in respect of the Corporation shall mean any
          entity controlled by the Corporation, (b) "Alleghany" means Alleghany
          Corporation, a Delaware corporation, all successors to Alleghany
          Corporation by way of merger, consolidation or sale of all or
          substantially all of its assets, and all corporations, limited
          liability companies, joint ventures, partnerships, trusts,
          associations and other entities in which Alleghany Corporation (1)
          beneficially owns, either directly or indirectly, more than fifty
          percent (50%) of (i) the total combined voting power of all classes of
          voting securities of such entity, (ii) the total combined equity
          interests, or (iii) the capital or profit interests, in the case of a
          partnership; or (2) otherwise has the power to vote, either directly
          or indirectly, sufficient securities to elect a majority of the board
          of directors or similar governing body, but shall not include the
          Corporation or any entity controlled by the Corporation, and (c)
          "corporate opportunities" shall include, but not be limited to,
          business opportunities which the Corporation is financially able to
          undertake, which are, by their nature, in the line of the
          Corporation's business and are of practical advantage to it.
 
               E. Severability. To the extent that any provision of this Article
          NINTH is found to be invalid or unenforceable, such invalidity or
          unenforceability shall not affect the validity or enforceability of
          any other provision of this Certificate of Incorporation.
 
          TENTH: The Corporation shall not be governed by Section 203 of the
     General Corporation Law of the State of Delaware ("Section 203"), and the
     restrictions contained in Section 203 shall not apply to the Corporation.
 
          ELEVENTH: The Corporation reserves the right to amend, alter, change
     or repeal any provision contained in this Amended and Restated Certificate
     of Incorporation, and any other provisions authorized by the laws of the
     State of Delaware at the time in force may be added or inserted, in the
     manner now or hereafter provided herein or by statute, and all rights,
     preferences and privileges of whatsoever nature
 
 
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     conferred upon stockholders, directors or any other persons whomsoever by
     and pursuant to this Amended and Restated Certificate of Incorporation in
     its present form or as amended are granted subject to the rights reserved
     in this Article ELEVENTH.