<PAGE>
                                                                      Exhibit 3B

                                     BY-LAWS

                                       of

                               COGNEX CORPORATION
<PAGE>
                                     BY-LAWS

                                       of

                               COGNEX CORPORATION

                                TABLE OF CONTENT

ARTICLE 1.................................................................   4
ARTICLE 2.................................................................   4
ARTICLE 3.................................................................   4
    Section 3.1 Annual Meeting............................................   4
    Section 3.2  Special Meetings.........................................   6
    Section 3.3  Place of Meetings........................................   6
    Section 3.4  Notice of Meetings.......................................   7
    Section 3.5  Quorum...................................................   7
    Section 3.6  Action without Meeting...................................   8
    Section 3.7  Proxies and Voting.......................................   9
ARTICLE 4.................................................................   9
    Section 4.1  Enumeration, Election and Term of Office.................   9
    Section 4.2  Powers...................................................  11
    Section 4.3  Meetings of Directors....................................  12
    Section 4.4  Quorum of Directors......................................  12
    Section 4.5 Consent in Lieu of Meeting and Participation in
        Meetings by Communications Equipment.............................   13
    Section 4.6  Committees...............................................  13
ARTICLE 5.................................................................  14
    Section 5.1  Enumeration, Election and Term of Office.................  14
    Section 5.2  President and Chairman of the Board......................  15
    Section 5.3  Treasurer and Assistant Treasurer........................  15
    Section 5.4  Clerk and Assistant Clerk................................  16
    Section 5.5  Secretary of the Board and Assistant Secretary...........  16
    Section 5.6  Temporary Clerk and Temporary Secretary..................  16
    Section 5.7  Other Powers and Duties..................................  17
ARTICLE 6.................................................................  17
    Section 6.1  Resignations.............................................  17
    Section 6.2  Removals.................................................  17
    Section 6.3  Vacancies................................................  18
ARTICLE 7.................................................................  19
    Section 7.1  Definitions..............................................  19
    Section 7.2  Right to Indemnification.................................  20
    Section 7.3  Indemnification Not Available............................  20
    Section 7.4  Compromise or Settlement.................................  20
    Section 7.5  Advances.................................................  20


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<PAGE>
    Section 7.6  Not Exclusive............................................  21
    Section 7.7  Insurance................................................  21
ARTICLE 8.................................................................  21
    Section 8.1  Stock Authorized.........................................  21
    Section 8.2  Issue of Authorized Unissued Capital Stock...............  21
    Section 8.3  Certificates of Stock....................................  22
    Section 8.4  Replacement Certificate..................................  23
    Section 8.5  Transfers................................................  24
    Section 8.6  Record Date..............................................  24
ARTICLE 9.................................................................  25
    Section 9.1  Execution of Papers......................................  25
    Section 9.2  Voting of Securities.....................................  25
    Section 9.3  Corporate Seal...........................................  26
    Section 9.4  Corporate Records........................................  26
ARTICLE 10................................................................  26


                                      -3-

<PAGE>
                                     BY-LAWS

                                       of

                               COGNEX CORPORATION

                                    ARTICLE 1

                            Articles of Organization

      The name and purposes of the Corporation shall be as set forth in the
Articles of Organization. These By-Laws, the powers of the Corporation and its
Directors and stockholders, and all matters concerning the conduct and
regulation of the business of the Corporation, shall be subject to such
provisions in regard thereto, if any, as are set forth in the Articles of
Organization. All references in these By-Laws to the Articles of Organization
shall be construed to mean the Articles of Organization of the Corporation as
from time to time amended or restated.

                                    ARTICLE 2

                                   Fiscal Year

      Except as from time to time otherwise determined by the Directors, the
fiscal year of the Corporation shall be the twelve months ending on December 31.

                                   ARTICLE 3

                            Meetings of Stockholders

      Section 3.1 Annual Meeting

      The Annual Meeting of the Stockholders shall be held at 10:00 o'clock A.M.
on the second Tuesday of April in each year. Purposes for which an annual
meeting is to be held, additional to those prescribed by law and by these
By-Laws, may be specified by the President or by the Directors.


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<PAGE>
      If such annual meeting has not been held on the day herein provided
therefor, a special meeting of the stockholders in lieu of the annual meeting
may be held, and any business transacted or elections held at such special
meeting shall have the same effect as if transacted or held at the annual
meeting, and in such case all references in these By-Laws, except in this
Section 3.1, to the annual meeting of the stockholders shall be deemed to refer
to such special meeting. Any such special meeting shall be called, and the
purposes thereof shall be specified in the call, as provided in Section 3.2 of
this Article III.

      To be properly brought before the meeting, business must be of a nature
that is appropriate for consideration at an annual meeting and must be (i)
specified in the notice of meeting (or any supplement thereto) given by or at
the direction of the Board of Directors, (ii) otherwise properly brought before
the meeting by or at the direction of the Board of Directors, or (iii) otherwise
properly brought before the meeting by a stockholder. In addition to any other
applicable requirements, for business to be properly brought before the annual
meeting by a stockholder, the stockholder must have given timely Notice thereof
in writing to the Clerk of the corporation. To be timely, each such Notice must
be given either by personal delivery or by United States mail, postage prepaid,
to the Clerk of the corporation not later than (1) with respect to a matter to
be brought before an annual meeting of stockholders or special meeting in lieu
of an annual meeting, sixty (60) days prior to the date set forth in the By-Laws
for the annual meeting and (2) with respect to a matter to be brought before a
special meeting of the stockholders not in lieu of an annual meeting, the close
of business on the tenth (10th) day following the date on which notice of such
meeting is first given to Stockholders. The Notice shall set forth (i)
information concerning the stockholder, including his or her name and address;


                                      -5-
<PAGE>
(ii) a representation that the stockholder is entitled to vote at such meeting
and intends to appear in person or by proxy at the meeting to present the matter
specified in the Notice, and (iii) such other information as would be required
to be included in a proxy statement soliciting proxies for the presentation of
such matter to the meeting.

      Notwithstanding anything in these By-Laws to the contrary, no business
shall be transacted at the annual meeting except in accordance with the
procedures set forth in this Section; provided, however, that nothing in this
Section shall be deemed to preclude discussion by any stockholder of any
business properly brought before the annual meeting in accordance with these
By-Laws.

      Section 3.2 Special Meetings

      Special Meeting of the Stockholders may be called at any time by the
President, or by a majority of the Directors acting by vote or a written
instrument or instruments signed by them. A Special Meeting of the Stockholders
shall be called by the Clerk or in the case of the death, absence, incapacity or
refusal of the Clerk, by any other officer upon written application of one or
more stockholders who hold at least forty (40) percent in interest of the
capital stock entitled to vote thereat and, also, upon application of any holder
of at least ten (10) percent of the capital stock entitled to vote at such
meeting, if such ten (10) percent holder also held on May 15, 1989 at least
fifteen (15) percent of the capital stock of the Corporation entitled on that
date to vote generally on the election of Directors. Such call shall state the
time, place and purpose of the meeting.

      Section 3.3 Place of Meetings


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<PAGE>
      All meetings of the stockholders shall be held at the principal office of
the Corporation in Massachusetts, unless a different place within Massachusetts
or, if permitted by the Articles of Organization, elsewhere within the United
States is designated by the President or by a majority of the Directors acting
by vote or by written instrument or instruments signed by them. Any adjourned
session of any meeting of the stockholders shall be held at such place within
Massachusetts or, if permitted by the Articles of Organization, elsewhere within
the United States as is designated in the vote of adjournment.

      Section 3.4 Notice of Meetings

      A written Notice of the place, date and hour of all meetings of
stockholders stating the purposes of the meeting shall be given at least seven
(7) days before the meeting to each stockholder entitled to vote thereat, by
leaving such Notice with him or at his residence or usual place of business, or
by mailing, postage prepaid, and addressed to such stockholder at his address as
it appears in the records of the Corporation. Such Notice shall be given by the
Clerk, or in the case of the death, absence, incapacity or refusal of the Clerk,
by any other officer or by a person designated either by the Clerk, by the
person or persons calling the meeting or by the Board of Directors. Whenever
Notice of a meeting is required to be given a stockholder under any provision of
law, of the Articles of Organization, or of these By-Laws, a written Waiver
thereof, executed before or after the meeting by such stockholder or his
attorney thereunto authorized, and filed with the records of the meeting, shall
be deemed equivalent to such Notice.

      Section 3.5 Quorum

      At any meeting of the stockholders, a quorum for the election of any
Director or for the consideration of any question shall consist of a majority in
interest of all stock issued,


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<PAGE>
outstanding and entitled to vote at such election or upon such question,
respectively, except that if two or more classes of stock are entitled to vote
as separate classes for the election of any Director or upon any question, then
in the case of each such class a quorum for the election of any Director or for
the consideration of such question shall consist of a majority in interest of
all stock of that class issued, outstanding and entitled to vote thereon. Stock
owned by the Corporation, if any, shall be disregarded in determining any
quorum. Both abstentions and broker non-votes are to be counted as present for
the purpose of determining the existence of a quorum for the transaction of
business at any meeting. Whether or not a quorum is present, any meeting may be
adjourned from time to time by a majority of the votes properly cast upon the
question, and the meeting may be held as adjourned without further notice.

      When a quorum for an election is present at any meeting, a plurality of
the votes properly cast for any office shall elect such office. When a quorum
for the consideration of a question is present at any meeting, a majority of the
votes properly cast upon the question shall decide the question; except that if
two or more classes of stock are entitled to vote as separate classes upon such
question, then in the case of each such class a majority of the votes of such
class properly cast upon the question shall decide the vote of that class upon
the question; and except in any case where a larger vote is required by law or
by the Articles of Organization. For purposes of determining the number of
shares voting on a particular proposal, abstentions and broker non-votes are not
to be counted as votes cast or shares voting.

      Section 3.6 Action without Meeting

      Any action required or permitted to be taken at any meeting of the
stockholders may be taken without a meeting if all stockholders entitled to vote
on the matter consent to the action in


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<PAGE>
writing and the written Consents are filed with the records of the meetings of
stockholders. Such Consents shall be treated for all purposes as a vote at a
meeting.

      Section 3.7 Proxies and Voting

      Except as may otherwise be provided in the Articles of Organization,
stockholders entitled to vote shall have one vote for each share of stock
entitled to vote owned by them. Stockholders entitled to vote may vote in person
or by proxy. No proxy dated more than six (6) months before the meeting named
therein shall be valid and no proxy shall be valid after the final adjournment
of such meeting. A proxy with respect to stock held in the name of two or more
persons shall be valid if executed by any one of them unless at or prior to the
exercise of the proxy the Corporation receives specific written notice to the
contrary from any one of them. A proxy purporting to be executed by or on behalf
of a stockholder shall be deemed valid unless challenged at or prior to its
exercise and the burden of proving invalidity shall rest on the challenger.
Proxies shall be filed with the Clerk, or person performing the duties of clerk,
at the meeting, or any adjournment thereof, before being voted.

      The Corporation shall not, directly or indirectly, vote upon any share of
its own stock. Both abstentions and broker non-votes are to be counted as
present for the purpose of determining the existence of a quorum for the
transaction of business at any meeting. However, for purposes of determining the
number of shares voting on a particular proposal, abstentions and broker
non-votes are not to be counted as votes cast or shares voting.

                                    ARTICLE 4

                                    Directors

      Section 4.1 Enumeration, Election and Term of Office


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<PAGE>
      The business and affairs of this corporation shall be managed under the
direction of a Board of Directors consisting of not fewer than three (3) nor
more than fifteen (15) Directors, the exact number to be determined from time to
time by resolution adopted by the affirmative vote of a majority of the entire
Board of Directors, such Board of Directors to be divided into such classes and
elected by such stockholders as have the right to vote thereon, for such terms
as are provided in the Articles of Organization. Each director shall hold office
until his successor shall have been elected and qualified, subject to Article VI
of these By-Laws. Whenever used in these By-Laws, the phrase "entire Board of
Directors" shall mean that number of Directors fixed by the most recent
resolution adopted pursuant to the preceding sentence prior to the date as of
which a determination of the number of Directors then constituting the entire
Board of Directors shall be relevant for any purpose under these By-Laws.
Subject to the foregoing limitations and the requirements of the Articles of
Organization, the Board of Directors may be enlarged by the stockholders at any
meeting or by the affirmative vote of a majority of the entire Board of
Directors then in office.

      Nominations for the election of Directors may be made by the Board of
Directors or a committee appointed by the Board of Directors or by any
stockholder entitled to vote generally in the election of Directors. However,
any stockholder entitled to vote generally in the election of Directors may
nominate one or more persons for election as Directors at a meeting only if
written Notice of such stockholder's intent to make such nomination or
nominations has been given, either by personal delivery or by United States
mail, postage prepaid, to the Clerk of the corporation not later than (1) with
respect to an election to be held at an annual meeting of stockholders or
special meeting in lieu of an annual meeting, sixty (60) days prior to the date
for


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<PAGE>
the annual meeting set forth in the By-Laws and (2) with respect to an election
to be held at a special meeting of stockholders not in lieu of an annual
meeting, the close of business on the tenth (10th) day following the date on
which notice of such meeting is first given to stockholders. Each such Notice to
the Clerk shall set forth (i) the name and addresses of the stockholder and his
or her nominees; (ii) a representation that the stockholder is entitled to vote
at such meeting and intends to appear in person or by proxy at the meeting to
nominate the person or persons specified in the notice; (iii) a description of
all arrangements or understandings between the stockholder and each such
nominee; (iv) such other information as would be required to be included in a
proxy statement soliciting proxies or the election of the nominees of such
stockholder; and (v) the consent of each nominee to serve as a director of the
corporation if so elected. The corporation may require any proposed nominee to
furnish such other information as may reasonably be required by the corporation
to determine the eligibility of such proposed nominee to serve as a director of
the corporation. The presiding officer of the meeting may, if the facts warrant,
determine that a nomination was not made in accordance with the foregoing
procedure, and if he should so determine, he shall so declare to the meeting and
the defective nomination shall be disregarded.

      No director need be a stockholder. Any election of directors by the
stockholders shall be by ballot if so requested by any stockholder entitled to
vote thereon.

      Section 4.2 Powers

      The business of the Corporation shall be managed by the Board of
Directors, which shall exercise all the powers of the Corporation except as
otherwise required by law, by the Articles of Organization or by these By-Laws.
In the event of one or more vacancies in the Board of


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<PAGE>
Directors, the remaining Directors, if at least two (2) Directors still remain
in office, may exercise the powers of the full Board until such vacancy or
vacancies are filled.

      Section 4.3 Meetings of Directors

      Regular meetings of the Directors may be held without notice at such
places and at such times as may be fixed from time to time by the Directors. A
regular meeting of the Directors may be held without notice immediately
following the Annual Meeting of Stockholders or any Special Meeting held in lieu
thereof.

      Special Meetings of Directors may be called by the Chairman of the Board,
the President, the Treasurer or any two (2) or more Directors, or if there shall
be less than three (3) Directors by any one (1) Director, and shall be held at
such time and place as specified in the Call. Reasonable notice of each special
meeting of the Directors shall be given to each Director. Such notice may be
given by the Secretary or Assistant Secretary of the Board, the Clerk or any
Assistant Clerk or by the officer or one of the Directors calling the meeting.
Notice to a Director shall in any case be sufficient if sent by telegram at
least forty-eight (48) hours or by mail at least ninety-six (96) hours before
the meeting addressed to him at his usual or last known business or residence
address, or if given to him at least forty-eight (48) hours before the meeting
in person or by telephone or by handing him a written Notice. Notice of a
meeting need not be given to any Director if a written Waiver of Notice,
executed by him, before or after the meeting, is filed with the records of the
meeting, or to any Director who attends the meeting without protesting prior
thereto or at its commencement the lack of notice to him. A Notice or Waiver of
Notice need not specify the purposes of the meeting.

      Section 4.4 Quorum of Directors


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<PAGE>
      At any meeting of the Directors, a quorum for any election or for the
consideration of any question shall consist of a majority of the Directors then
in office. Whether or not a quorum is present any meeting may be adjourned from
time to time by a majority of the votes properly cast upon the question, and the
meeting may be held as adjourned without further Notice. When a quorum is
present at any meeting, the votes of a majority of the Directors present shall
be requisite and sufficient for election to any office and shall decide any
question brought before such meeting, except in any case where a larger vote is
required by law, by the Articles of Organization or by these By-Laws.

      Section 4.5 Consent in Lieu of Meeting and Participation in Meetings by
Communications Equipment

      Any action required or permitted to be taken at any meeting of the
Directors may be taken without a meeting if all the Directors consent to the
action in writing and the written Consents are filed with the records of the
meetings of the Directors. Such Consents shall be treated for all purposes as a
vote of the Directors at a meeting.

      Members of the Board of Directors or any Committee designated thereby may
participate in a meeting of such Board or Committee by means of a conference
telephone or similar communications equipment by means of which all persons
participating in the meeting can hear each other at the same time and
participation by such means shall constitute presence in person at a meeting.

      Section 4.6 Committees

      By vote of a majority of the Directors then in office, the Directors may
elect from their own number an Executive Committee or other Committees and may
by like vote delegate to any such Committee some or all of their powers except
those which by law may not be delegated.


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<PAGE>
                                   ARTICLE 5

                                    Officers

      Section 5.1 Enumeration, Election and Term of Office

      The officers of the Corporation shall include a President, a Treasurer and
a Clerk, who shall be chosen by the Directors at their first meeting following
the Annual Meeting of the Stockholders. Each of them shall hold his office until
the next annual election to the office which he holds and until his successor is
chosen and qualified or until he sooner dies, resigns, is removed or becomes
disqualified.

      The Directors may choose one of their number to be Chairman of the Board
and determine his powers, duties and term of office. The Directors may at any
time appoint such other officers, including one or more Vice Presidents,
Assistant Treasurers, Assistant Clerks, a Secretary of the Board and an
Assistant Secretary of the Board as they deem wise, and may determine their
respective powers, duties and terms of office.

      No officer need be a stockholder or a Director except that the Chairman of
the Board shall be a Director. The same person may hold more than one office,
except that no person shall be both President and Clerk.

      The Company may also designate individuals as divisional, group, or
segment vice presidents or vice presidents of a particular function, which
individual shall carry such title on a non-executive basis and not as executive
officers of the Corporation. Said non-executive vice presidents may be
designated by the Board of Directors or by the President pursuant to Board
resolutions so-authorizing the President to appoint non-executive vice
presidents on a particular


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<PAGE>
occasion or from time to time in his discretion, said honorary vice presidents
to be titled "Vice President (specific area of function)".

      Section 5.2 President and Chairman of the Board

      The President shall be the Chief Executive Officer of the Corporation and,
subject to the control and direction of the Directors, shall have general
supervision and control of the business of the Corporation. He shall preside at
all meetings of the stockholders at which he is present, and, if he is a
Director, at all meetings of the Directors if there shall be no Chairman of the
Board or in the absence of the Chairman of the Board.

      If there shall be a Chairman of the Board, he shall make his counsel
available to the other officers of the Corporation, and shall have such other
duties and powers as may from time to time be conferred on him by the Directors.
He shall preside at all meetings of the Directors at which he is present, and,
in the absence of the President, at all meetings of stockholders.

      Section 5.3 Treasurer and Assistant Treasurer

      The Treasurer shall have the custody of the funds and valuable books and
papers of the Corporation, except such as are directed by these By-Laws to be
kept by the Clerk or by the Secretary of the Board. He shall perform all other
duties usually incident to his office, and shall be at all times subject to the
control and direction of the Directors. If required by the Directors, he shall
give bond in such form and amount and with such sureties as shall be determined
by the Directors.

      If the Treasurer is absent or unavailable, any Assistant Treasurer shall
have the duties and powers of Treasurer and shall have such further duties and
powers as the Directors shall from time to time determine.

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<PAGE>
      Section 5.4 Clerk and Assistant Clerk

      If the Corporation shall not have a resident agent appointed pursuant to
law, the Clerk shall be a resident of the Commonwealth of Massachusetts. The
Clerk shall record all proceedings of the stockholders in a book to be kept
therefor. In case a Secretary of the Board is not elected, the Clerk shall also
record all proceedings of the Directors in a book to be kept therefor.

      If the Corporation shall not have a transfer agent, the Clerk shall also
keep or cause to be kept the stock and transfer records of the Corporation,
which shall contain the names of all stockholders and the record address and the
amount of stock held by each.

      If the Clerk is absent or unavailable, any Assistant Clerk shall have the
duties and powers of the Clerk and shall have such further duties and powers as
the Directors shall from time to time determine.

      Section 5.5 Secretary of the Board and Assistant Secretary

      If a Secretary of the Board is elected, he shall record all proceedings of
the Directors in a book to be kept therefor.

      If the Secretary of the Board is absent or unavailable, any Assistant
Secretary shall have the duties and powers of the Secretary and shall have such
further duties and powers as the Directors shall from time to time determine.

      If no Secretary or Assistant Secretary has been elected, or if, having
been elected, no Secretary or Assistant Secretary is present at a meeting of the
Directors, the Clerk or an Assistant Clerk shall record the proceedings of the
Directors.

      Section 5.6 Temporary Clerk and Temporary Secretary


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<PAGE>
      If no Clerk or Assistant Clerk shall be present at any meeting of the
stockholders, or if no Secretary, Assistant Secretary, Clerk or Assistant Clerk
shall be present at any meeting of the Directors, the person presiding at the
meeting shall designate a Temporary Clerk or Secretary to perform the duties of
Clerk or Secretary.

      Section 5.7 Other Powers and Duties

      Each officer shall, subject to these By-Laws and to the control and
direction of the Directors, have in addition to the duties and powers
specifically set forth in these By-Laws, such duties and powers as are
customarily incident to his office and such additional duties and powers as the
Directors may from time to time determine.

                                    ARTICLE 6

                      Resignations, Removals and Vacancies

      Section 6.1 Resignations

      Any Director or officer may resign at any time by delivering his
resignation in writing to the President or the Clerk or to a meeting of the
Directors. Such resignations shall take effect at such time as is specified
therein, or if no such time is so specified, then upon delivery thereof to the
President or the Clerk or to a meeting of the Directors.

      Section 6.2 Removals

      Directors, including Directors elected by the Directors to fill vacancies
in the Board, may be removed from office (a) with cause by vote of the holders
of a majority of the shares issued and outstanding and entitled to vote
generally in the election of Directors; (b) with or without cause by vote of the
holders of at least 80% of the votes entitled to be cast by the holders of all
shares of the corporation entitled to vote generally in the election of
Directors, voting together as


                                     - 17 -
<PAGE>
a single class; (c) with cause by vote of a majority of the Directors then in
office or (d) without cause by vote of at least 80% of the Directors then in
office (including the Director to be removed in calculating said percentage);
provided that the Directors of a class elected by a particular class of
stockholders may be removed only by vote of the holders of a majority of the
shares of such class.

      The Directors may terminate or modify the authority of any agent or
employee. The Directors may remove any officer from office with or without
assignment of cause by vote of a majority of the Directors then in office.

      If cause is assigned for removal of any Director or officer, such Director
or officer may be removed only after a reasonable notice and opportunity to be
heard before the body proposing to remove him.

      No Director or officer who resigns or is removed shall have any right to
any compensation as such Director or officer for any period following his
resignation or removal, or any right to damages on account of such removal
whether his compensation be by the month or by the year or otherwise; provided,
however, that the foregoing provision shall not prevent such Director or officer
from obtaining damages for breach of any contract of employment legally binding
upon the corporation.

      Section 6.3 Vacancies

      Any vacancy in the Board of Directors, including a vacancy resulting from
an enlargement of the Board, may be filled by the Directors by vote of a
majority of the remaining Directors then in office, though less than a quorum,
or by the stockholders at a meeting called for the purpose provided that any
vacancy created by the stockholders may be filled by the


                                     - 18 -
<PAGE>
stockholders at the same meeting. Any Director elected in accordance with the
preceding sentence shall hold office for the remainder of the full term of the
class of Directors in which the new Directorship was created or the vacancy
occurred and until such Directors' successor shall have been elected and
qualified or until he sooner dies, resigns, is removed or becomes disqualified.

      If the office of any officer becomes vacant, the Directors may choose or
appoint a successor by vote of a majority of the Directors present at the
meeting at which such choice or appointment is made.

      Each such successor shall hold office for the unexpired term of his
predecessor and until his successor shall be chosen or appointed and qualified,
or until he sooner dies, resigns, is removed or becomes disqualified.

                                    ARTICLE 7

                     Indemnification of Directors and Others


      Section 7.1 Definitions

      For purposes of this Article 7:

      (a) "Director/officer" means any person who is serving or has served as a
Director, officer or employee of the Corporation appointed or elected by the
Board of Directors or the stockholders of the Corporation, or any Director,
officer or employee of the Corporation who is serving or has served at the
request of the Corporation as a Director, officer, trustee, principal, partner,
employee or other agent of any other organization.

      (b) "Proceeding" means any action, suit or proceeding, civil or criminal,
brought or threatened in or before any court, tribunal, administrative or
legislative body or agency.



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<PAGE>
      (c) "Expense" means any fine or penalty, and any liability fixed by a
judgment, order, decree or award in a Proceeding, any amount reasonably paid in
settlement of a Proceeding and any professional fees and other disbursements
reasonably incurred in connection with a Proceeding.

      Section 7.2 Right to Indemnification

      Except as limited by law or as provided in Sections 7.3 and 7.4 of this
Article 7, each Director/officer (and his heirs and personal representatives)
shall be indemnified by the Corporation against any Expense incurred by him in
connection with each Proceeding in which he is involved as a result of his
serving or having served as a Director/officer.

      Section 7.3 Indemnification Not Available

      No indemnification shall be provided to a Director/officer with respect to
a Proceeding as to which it shall have been adjudicated that he did not act in
good faith in the reasonable belief that his action was in the best interests of
the Corporation.

      Section 7.4 Compromise or Settlement

      In the event that a Proceeding is compromised or settled so as to impose
any liability or obligation on a Director/officer or upon the Corporation, no
indemnification shall be provided as to said Director/officer with respect to
such Proceeding if such Director/officer shall have been adjudicated not to have
acted in good faith in the reasonable belief that his action was in the best
interests of the Corporation.

      Section 7.5 Advances

      The Corporation shall pay sums on account of indemnification in advance of
a final disposition of a Proceeding upon receipt of an undertaking by the
Director/officer to repay such


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<PAGE>
sums if it is subsequently established that he is not entitled to
indemnification pursuant to Sections 7.3 and 7.4 hereof, which undertaking may
be accepted without reference to the financial ability of such person to make
repayment.

      Section 7.6 Not Exclusive

      Nothing in this Article 7 shall limit any lawful rights to indemnification
existing independently of this Article 7.

      Section 7.7 Insurance

      The provisions of this Article 7 shall not limit the power of the Board of
Directors to authorize the purchase and maintenance of insurance on behalf of
any Director/officer against any Expense, whether or not the Corporation would
have the power to indemnify him against such Expense under this Article 7.

                                    ARTICLE 8

                                      Stock


      Section 8.1 Stock Authorized

      The total number of shares and the par value, if any, of each class of
stock which the Corporation is authorized to issue, and if more than one class
is authorized, the descriptions, preferences, voting powers, qualifications and
special and relative rights and privileges as to each class and any series
thereof, shall be as stated in the Articles of Organization.

      Section 8.2 Issue of Authorized Unissued Capital Stock

      Any unissued capital stock from time to time authorized under the Articles
of Organization and Amendments thereto may be issued, by vote of the Directors.
No stock shall be issued unless the cash, so far as due, or the property,
services or expenses for which it was


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<PAGE>
authorized to be issued, has been actually received or incurred by, or conveyed
or rendered to, the Corporation, or is in its possession as surplus.

      Section 8.3 Certificates of Stock

      Each stockholder shall be entitled to a certificate in such form as may be
prescribed from time to time by the Directors, stating the number and the class
and the designation of the series, if any, of the shares held by him. Such
certificates shall be signed by the President or a Vice President and by the
Treasurer or an Assistant Treasurer. Such signatures may be facsimiles if the
certificate is signed by a transfer agent, or by a registrar, other than a
Director, officer or employee of the Corporation. In case any officer who has
signed or whose facsimile signature has been placed on such certificate shall
have ceased to be such officer before such certificate is issued, it may be
issued by the Corporation with the same effect as if he were such officer at the
time of its issue.

      Every certificate issued by the Corporation for shares of stock at a time
when such shares are subject to any restriction on transfer pursuant to the
Articles of Organization, the By-Laws or any agreement to which the Corporation
is a party shall have the restriction noted conspicuously on the certificate and
shall also set forth on the face or back of the certificate either the full text
of the restriction, or a statement of the existence of such restriction and a
statement that the Corporation will furnish a copy thereof to the holder of such
certificate upon written request and without charge. Every stock certificate
issued by the Corporation at a time when it is authorized to issue more than one
class or series of stock shall set forth upon the face or back of the
certificate either the full text of the preferences, voting powers,
qualifications and special and relative rights of the shares of each class and
series, if any, authorized to be issued, as set forth in


                                     - 22 -
<PAGE>
the Articles of Organization, or a statement of the existence of such
preferences, powers, qualifications and rights and a statement that the
Corporation will furnish a copy thereof to the holder of such certificate upon
written request and without charge.

      Section 8.4 Replacement Certificate

      In case of the alleged loss or destruction or the mutilation of a
certificate of stock, a new certificate may be issued in place thereof, upon
such conditions as the Directors may determine.




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<PAGE>
      Section 8.5 Transfers

      Subject to the restrictions, if any, imposed by the Articles of
Organization, the By-Laws or any agreement to which the Corporation is a party,
shares of stock shall be transferred on the books of the Corporation only by the
surrender to the Corporation or its transfer agent of the certificate
representing such shares properly endorsed or accompanied by a written
assignment of such shares or by a written power of attorney to sell, assign or
transfer such shares, properly executed, with necessary transfer stamps affixed,
and with such proof that the endorsement, assignment or power of attorney is
genuine and effective as the Corporation or its transfer agent may reasonably
require. Except as may otherwise be required by law, the Corporation shall be
entitled to treat the record holder of stock as shown on its books as the owner
of such stock for all purposes, including the payment of dividends and the right
to vote with respect thereto, regardless of any transfer, pledge or other
disposition of such stock, until the shares have been transferred on the books
of the Corporation in accordance with the requirements of these By-Laws. It
shall be the duty of each stockholder to notify the Corporation of his post
office address.

      Section 8.6 Record Date

      The Directors may fix in advance a time, which shall be not more than
sixty (60) days before the date of any meeting of stockholders or the date for
the payment of any dividend or the making of any distribution to stockholders or
the last day on which the consent or dissent of stockholders may be effectively
expressed for any purpose, as the record date for determining the stockholders
having the right to notice of and to vote at such meeting and any adjournment
thereof or the right to receive such dividend or distribution or the right to
give such consent or


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<PAGE>
dissent, and in such case only stockholders of record on such date shall have
such right, notwithstanding any transfer of stock on the books of the
Corporation after the record date; or without fixing such record date the
Directors may for any such purposes close the transfer books for all or any part
of such period.

      If no record date is fixed and the transfer books are not closed:

      (1) The record date for determining stockholders having the right to
notice of or to vote at a meeting of stockholders shall be at the close of
business on the day next preceding the day on which notice is given.

      (2) The record date for determining stockholders for any other purpose
shall be at the close of business on the day on which the Board of Directors
acts with respect thereto.

                                    ARTICLE 9

                            Miscellaneous Provisions

      Section 9.1 Execution of Papers

      All deeds, leases, transfers, contracts, bonds, notes, releases, checks,
drafts and other obligations authorized to be executed on behalf of the
Corporation shall be signed by the President or the Treasurer except as the
Directors may generally or in particular cases otherwise determine.

      Section 9.2 Voting of Securities

      Except as the Directors may generally or in particular cases otherwise
determine, the President or the Treasurer may, on behalf of the Corporation (i)
waive Notice of any meeting of stockholders or shareholders of any other
corporation, or of any association, trust or firm, of which any securities are
held by this Corporation; (ii) appoint any person or persons to act as


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<PAGE>
proxy or attorney-in-fact for the Corporation, with or without substitution, at
any such meeting; and (iii) execute instruments of Consent to stockholder or
shareholder action taken without a meeting.

      Section 9.3 Corporate Seal

      The seal of the Corporation shall be a circular die with the name of the
Corporation, the word "Massachusetts" and the year of its incorporation cut or
engraved thereon, or shall be in such other form as the Board of Directors or
the stockholders may from time to time determine.

      Section 9.4 Corporate Records

      The original, or attested copies, of the Articles of Organization,
By-Laws, and the records of all meetings of incorporators and stockholders, and
the stock and transfer records, which shall contain the names of all
stockholders and the record address and the amount of stock held by each, shall
be kept in Massachusetts for inspection by the stockholders at the principal
office of the Corporation or at an office of the Clerk, or if the Corporation
shall have a transfer agent or a resident agent, at an office of either of them.
Said copies and records need not all be kept in the same office.

                                   ARTICLE 10

                                   Amendments

      These By-Laws may be altered, amended or repealed or new By-Laws enacted
by the affirmative vote of a majority of the entire Board of Directors (if
notice of the proposed alteration or amendment is contained in the notice of the
meeting at which such vote is taken or if all Directors are present) or at any
regular meeting of the stockholders (or at any special meeting thereof duly
called for that purpose) by the affirmative vote of a majority of the shares


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<PAGE>
represented and entitled to vote at such meeting (if notice of the proposed
alteration or amendment is contained in the notice of such meeting).

      Notwithstanding anything contained in the preceding paragraph of this
Article X to the contrary, either (i) the affirmative vote of the holders of at
least eighty (80%) percent of the votes entitled to be cast by the holders of
all shares of the corporation entitled to vote generally in the election of
Directors, voting together as a single class, or (ii) the affirmative vote of a
majority of the entire Board of Directors with the concurring vote of a majority
of the Continuing Directors, voting separately and as a subclass of Directors,
shall be required to alter, amend or repeal or adopt any provision inconsistent
with, Section 3.1 of Article III, Section 4.1 of Article IV, Section 6.1 and
Section 6.2 of Article VI and this paragraph of this Article X; provided however
that (notwithstanding any action by the Board of Directors) if such proposal is
put to a vote of the stockholders and receives the affirmative vote of each
holder of at least 15% of the votes entitled to be cast by the holders of all
shares of the corporation entitled to vote generally in the election of
Directors, voting together as a single class (which holders also held on May 15,
1989 at least 15% of the shares of the corporation entitled on that date to vote
generally in the election of Directors), then such proposal shall require only
the affirmative vote of a majority of the shares represented and entitled to
vote at such meeting. For purposes of this Article X, the term "Continuing
Director" shall have the meaning ascribed to it in Article 6 of the Articles of
Organization of the corporation.




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