INVESTORS BANCORP, INC.
                          CERTIFICATE OF INCORPORATION
 
         FIRST: The name of the Corporation is Investors Bancorp, Inc.
(hereinafter referred to as the "Corporation").
 
         SECOND: The address of the registered office of the Corporation 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 registered agent at that
address is The Corporation Trust Company.
 
         THIRD: The purpose of the Corporation is to engage in any lawful act or
activity for which a corporation may be organized under the General Corporation
Law of Delaware.
 
         FOURTH:
 
         A.       The total number of shares of all classes of stock which the
Corporation shall have authority to issue is two hundred and fifty million
(250,000,000) consisting of:
 
         1.       Fifty million (50,000,000) shares of preferred stock, par
value one cent ($0.01) per share (the "Preferred Stock"); and
 
         2.       Two hundred million (200,000,000) shares of Common Stock, par
value one cent ($0.01) per share (the "Common Stock").
 
         B.       The Board of Directors is authorized, subject to any
limitations prescribed by law, to provide for the issuance of the shares of
Preferred Stock in series, and by filing a certificate pursuant to the
applicable law of the State of Delaware (such certificate being hereinafter
referred to as a "Preferred Stock Designation"), to establish from time to time
the number of shares to be included in each such series, and to fix the
designation, powers, preferences, and rights of the shares of each such series
and any qualifications, limitations or restrictions thereof. 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 Common Stock, without a vote of the holders of
the Preferred Stock, or of any series thereof, unless a vote of any such holders
is required pursuant to the terms of any Preferred Stock Designation.
 
         C.       1. Notwithstanding any other provision of this Certificate of
Incorporation or the bylaws of the Corporation, in no event shall any record
owner of any outstanding Common Stock which is beneficially owned, directly or
indirectly, by a person who, as of any record date for the determination of
stockholders entitled to vote on any matter, beneficially owns in excess of 10%
of the then - outstanding shares of Common Stock (the "Limit"), be entitled, or
permitted to any vote in respect of the shares held in excess of the Limit,
except that this restriction on voting shall not apply to Investors Bancorp, MHC
(the "Mutual Holding Company"), or to any tax qualified employee stock benefit
plan established by the Corporation (or a subsidiary thereof), each of which
shall be able to vote with respect to shares held in excess of the Limit. The
number of votes which may be cast by any record owner by virtue of the
provisions hereof in respect of Common Stock beneficially owned by such person
owning shares in excess of the Limit shall be a number equal to the total number
of votes which a single record owner of all
 
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Common Stock owned by such person would be entitled to cast subject to this
Section C of this Article FOURTH, multiplied by a fraction, the numerator of
which is the number of shares of such class or series which are both
beneficially owned by such person and owned of record by such record owner and
the denominator of which is the total number of shares of Common Stock
beneficially owned by such person owning shares in excess of the Limit.
 
                  2.       The following definitions shall apply to this Section
C of this Article
 
FOURTH:
 
                  (a)      "Affiliate" shall have the meaning ascribed to it in
                           Rule 12b-2 of the General Rules and Regulations under
                           the Securities Exchange Act of 1934, as in effect on
                           the date of filing of this Certificate of
                           Incorporation.
 
                  (b)      "Beneficial ownership" shall be determined pursuant
                           to Rule 13d-3 of the General Rules and Regulations
                           under the Securities Exchange Act of 1934 (or any
                           successor rule or statutory provision), or, if said
                           Rule 13d-3 shall be rescinded and there shall be no
                           successor rule or statutory provision thereto,
                           pursuant to said Rule 13d-3 as in effect on the date
                           of filing of this Certificate of Incorporation;
                           provided, however, that a person shall, in any event,
                           also be deemed the "beneficial owner" of any Common
                           Stock:
 
                           (1)      which such person or any of is affiliates
                                    beneficially owns, directly or indirectly;
                                    or
 
                           (2)      which such person or any of its affiliates
                                    has (i) the right to acquire (whether such
                                    right is exercisable immediately or only
                                    after the passage of time), pursuant to any
                                    agreement, arrangement or understanding or
                                    upon the exercise of conversion rights,
                                    exchange rights, warrants, or options or
                                    otherwise, or (ii) sole or shared voting or
                                    investment power with respect thereto
                                    pursuant to any agreement, arrangement,
                                    understanding, relationship or otherwise
                                    (but shall not be deemed to be the
                                    beneficial owner of any voting shares solely
                                    by reason of a revocable proxy granted for a
                                    particular meeting of stockholders, pursuant
                                    to a public solicitation of proxies for such
                                    meeting, with respect to shares of which
                                    neither such person nor any such affiliate
                                    is otherwise deemed the beneficial owner);
                                    or
 
                           (3)      which are beneficially owned, directly or
                                    indirectly, by any other person with which
                                    such first mentioned person or any of its
                                    affiliates acts as a partnership, limited
                                    partnership, syndicate or other group
                                    pursuant to any agreement, arrangement or
                                    understanding for the purpose of acquiring,
                                    holding, voting or disposing of any shares
                                    of capital stock of this Corporation;
 
                           and provided further, however, that (1) no Director
                           or Officer of this Corporation (or any affiliate of
                           any such Director or Officer) shall, solely
 
 
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                           by reason of any or all of such Directors or Officers
                           acting in their capacities as such, be deemed, for
                           any purposes hereof, to beneficially own any Common
                           Stock beneficially owned by another such Director or
                           Officer (or any affiliate thereof), and (2) neither
                           any employee stock ownership plan or similar plan of
                           this Corporation or any subsidiary of this
                           Corporation, nor any trustee with respect thereto or
                           any affiliate of such trustee (solely by reason of
                           such capacity of such trustee), shall be deemed, for
                           any purposes hereof, to beneficially own any Common
                           Stock held under any such plan. For purposes of
                           computing the percentage beneficial ownership of
                           Common Stock of a person the outstanding Common Stock
                           shall include shares deemed owned by such person
                           through application of this subsection but shall not
                           include any other Common Stock which may be issuable
                           by this Corporation pursuant to any agreement, or
                           upon exercise of conversion rights, warrants or
                           options, or otherwise. For all other purposes, the
                           outstanding Common Stock shall include only Common
                           Stock then outstanding and shall not include any
                           Common Stock which may be issuable by this
                           Corporation pursuant to any agreement, or upon the
                           exercise of conversion rights, warrants or options,
                           or otherwise.
 
                  (c)      A "person" shall include an individual, firm, a group
                           acting in concert, a corporation, a partnership, an
                           association, a joint venture, a pool, a joint stock
                           company, a trust, an unincorporated organization or
                           similar company, a syndicate or any other group
                           formed for the purpose of acquiring, holding or
                           disposing of securities or any other entity.
 
                  3.       The Board of Directors shall have the power to
construe and apply the provisions of this section and to make all determinations
necessary or desirable to implement such provisions, including but not limited
to matters with respect to (i) the number of shares of Common Stock beneficially
owned by any person, (ii) whether a person is an affiliate of another, (iii)
whether a person has an agreement, arrangement, or understanding with another as
to the matters referred to in the definition of beneficial ownership, (iv) the
application of any other definition or operative provision of the section to the
given facts, or (v) any other matter relating to the applicability or effect of
this section.
 
                  4.       The Board of Directors shall have the right to demand
that any person who is reasonably believed to beneficially own Common Stock in
excess of the Limit (or holds of record Common Stock beneficially owned by any
person in excess of the Limit) supply the Corporation with complete information
as to (i) the record owner(s) of all shares beneficially owned by such person
who is reasonably believed to own shares in excess of the Limit, (ii) any other
factual matter relating to the applicability or effect of this section as may
reasonably be requested of such person.
 
                  5.       Except as otherwise provided by law or expressly
provided in this section, the presence, in person or by proxy, of the holders of
record of shares of capital stock of the Corporation entitling the holders
thereof to cast a majority of the votes (after giving effect, if required, to
the provisions of this section) entitled to be cast by the holders of shares of
capital
 
 
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<PAGE>
 
stock of the Corporation entitled to vote shall constitute a quorum at all
meetings of the stockholders, and every reference in this Certificate of
Incorporation to a majority or other proportion of capital stock (or the holders
thereof) for purposes of determining any quorum requirement or any requirement
for stockholder consent or approval shall be deemed to refer to such majority or
other proportion of the votes (or the holders thereof) then entitled to be cast
in respect of such capital stock, after giving effect to the provisions of this
section.
 
                  6.       Any constructions, applications, or determinations
made by the Board of Directors pursuant to this section in good faith and on the
basis of such information and assistance as was then reasonably available for
such purpose shall be conclusive and binding upon the Corporation and its
stockholders.
 
                  7.       In the event any provision (or portion thereof) of
this section shall be found to be invalid, prohibited or unenforceable for any
reason, the remaining provisions (or portions thereof) of this section shall
remain in full force and effect, and shall be construed as if such invalid,
prohibited or unenforceable provision had been stricken herefrom or otherwise
rendered inapplicable, it being the intent of this Corporation and its
stockholders that such remaining provision (or portion thereof) of this section
remain, to the fullest extent permitted by law, applicable and enforceable as to
all stockholders, including stockholders owning an amount of stock over the
Limit, notwithstanding any such finding.
 
         FIFTH: The following provisions are inserted for the management of the
business and the conduct of the affairs of the Corporation, and for further
definition, limitation and regulation of the powers of the Corporation and of
its Directors and stockholders:
 
         A.       The business and affairs of the Corporation shall be managed
by or under the direction of the Board of Directors. In addition to the powers
and authority expressly conferred upon them by statute or by this Certificate of
Incorporation or the Bylaws of the Corporation, the Directors are hereby
empowered to exercise all such powers and do all such acts and things as may be
exercised or done by the Corporation.
 
         B.       The Directors of the Corporation need not be elected by
written ballot unless the Bylaws so provide. Stockholders shall not be permitted
to cumulate their votes for the election of Directors.
 
         C.       Any action required or permitted to be taken by the
stockholders of the Corporation must be effected at a duly called annual or
special meeting of stockholders of the Corporation or may be effected by the not
less than unanimous consent in writing by such stockholders without a meeting.
 
         D.       Special meetings of stockholders of the Corporation may be
called only by the Board of Directors pursuant to a resolution adopted by a
majority of the total number of authorized directorships (whether or not there
exist any vacancies in previously authorized directorships at the time any such
resolution is presented to the Board for adoption) (the "Whole Board") or as
otherwise provided in the Bylaws.
 
 
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<PAGE>
 
         SIXTH:
 
         A.       The number of Directors shall be fixed from time to time
exclusively by the Board of Directors pursuant to a resolution adopted by a
majority of the Whole Board. The Directors shall be divided into three classes,
with the term of office of the first class to expire at the first annual meeting
of stockholders, the term of office of the second class to expire at the annual
meeting of stockholders one year thereafter and the term of office of the third
class to expire at the annual meeting of stockholders two years thereafter. At
each annual meeting of stockholders following such initial classification and
election, Directors elected to succeed those Directors whose terms expire shall
be elected for a term of office to expire at the third succeeding annual meeting
of stockholders after their election.
 
         B.       Subject to the rights of the holders of any series of
Preferred Stock then outstanding, 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, retirement, 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 Directors so chosen
shall hold office for a term expiring at the annual meeting of stockholders at
which the term of office of the class to which they have been chosen expires. No
decrease in the number of Directors constituting the Board of Directors shall
shorten the term of any incumbent Director.
 
         C.       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.
 
         D.       Subject to the rights of the holders of any series of
Preferred Stock then outstanding, any Director, or the entire Board of
Directors, may be removed from office at any time, but only for cause and only
by the affirmative vote of the holders of at least 80% of the voting power of
all of the then-outstanding shares of capital stock of the Corporation entitled
to vote generally in the election of Directors (after giving effect to the
provisions of Article FOURTH of this Certificate of Incorporation ("Article
FOURTH")), voting together as a single class.
 
         SEVENTH: The Board of Directors is expressly empowered to adopt, amend
or repeal the Bylaws of the Corporation. Any adoption, amendment or repeal of
the Bylaws of the Corporation by the Board of Directors shall require the
approval of a majority of the Whole Board. The stockholders shall also have
power to adopt, amend or repeal the Bylaws of the Corporation; provided,
however, that, in addition to any vote of the holders of any class or series of
stock of the Corporation required by law or by this Certificate of
Incorporation, the affirmative vote of the holders of at least 80% 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 (after
giving effect to the provisions of Article FOURTH), voting together as a single
class, shall be required to adopt, amend or repeal any provisions of the Bylaws
of the Corporation.
 
         EIGHTH: The Board of Directors of the Corporation, when evaluating any
offer of another Person (as defined in Article FOURTH hereof) to (A) make a
tender or exchange offer
 
 
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<PAGE>
 
for any equity security of the Corporation, (B) merge or consolidate the
Corporation with another corporation or entity or (C) purchase or otherwise
acquire all or substantially all of the properties and assets of the
Corporation, may, in connection with the exercise of its judgment in determining
what is in the best interest of the Corporation and its stockholders, give due
consideration to all relevant factors, including, without limitation, the social
and economic effect of acceptance of such offer on the Corporation's present and
future customers and employees and those of its subsidiaries; on the communities
in which the Corporation and its Subsidiaries operate or are located; on the
ability of the Corporation to fulfill its corporate objectives as a savings bank
holding company and on the ability of its subsidiary savings bank to fulfill the
objectives of a stock savings bank under applicable statutes and regulations.
 
         NINTH:
 
         A.       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, Officer, employee or agent 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, employee or agent or in any other capacity while serving as a
Director, Officer, employee or agent, shall be indemnified and held harmless by
the Corporation to the fullest extent authorized by the Delaware General
Corporation Law, 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 Section C hereof 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.
 
         B.       The right to indemnification conferred in Section A of this
Article NINTH shall include the right to be paid by the Corporation the expenses
incurred in defending any such proceeding in advance of its final disposition
(hereinafter an "advancement of expenses"); provided, however, that, if the
Delaware General Corporation Law 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
this Section or otherwise. The rights to indemnification and to the advancement
of expenses conferred in Sections A and B of this Article NINTH shall be
contract rights and such rights shall continue as
 
 
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<PAGE>
 
to an indemnitee who has ceased to be a Director, Officer, employee or agent and
shall inure to the benefit of the indemnitee's heirs, executors and
administrators.
 
         C.       If a claim under Section A or B of this Article NINTH is not
paid in full by the Corporation within sixty 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 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 also shall be
entitled to be paid 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 by the
Corporation 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 Delaware General Corporation Law. Neither the
failure of the Corporation (including its Board of 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 Delaware General Corporation Law, nor an actual
determination by the Corporation (including its Board of 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 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 Article NINTH or otherwise shall be on the Corporation.
 
         D.       The rights to indemnification and to the advancement of
expenses conferred in this Article NINTH shall not be exclusive of any other
right which any person may have or hereafter acquire under any statute, the
Corporation's Certificate of Incorporation, Bylaws, agreement, vote of
stockholders or disinterested Directors or otherwise.
 
         E.       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 Delaware General Corporation Law.
 
         F.       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 NINTH with respect to the
indemnification and advancement of expenses of Directors and Officers of the
Corporation.
 
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<PAGE>
 
 
         TENTH: A Director of this Corporation shall not be personally liable to
the Corporation, its stockholders or to depositors of its savings bank
subsidiary 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, its stockholders or to depositors of its savings bank subsidiary,
(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
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 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 Delaware General Corporation Law, as so amended.
 
         Any repeal or modification of the foregoing paragraph by the
stockholders of the Corporation shall not adversely affect any right or
protection of a Director of the Corporation existing at the time of such repeal
or modification.
 
         ELEVENTH: At all times so long as the Mutual Holding Company shall be
in existence the Mutual Holding Company shall own at least a majority of the
Voting Stock of this Corporation and the Corporation shall not be authorized to
issue any shares of Voting Stock or take any action while the Mutual Holding
Company is in existence if after such issuance or action the Mutual Holding
Company shall own less than the majority of the Corporation's Voting Stock. For
these purposes, "Voting Stock" means common stock or preferred stock, or similar
interests if the shares by statute, charter or in any manner, entitle the holder
(i) to vote for or to select directors of the Corporation; and (ii) to vote on
or to direct the conduct of the operations or other significant policies of the
Corporation. Notwithstanding anything in the preceding sentence, preferred stock
is not "Voting Stock" if: (i) voting rights associated with the preferred stock
are limited solely to the type customarily provided by statute with regard to
matters that would significantly and adversely affect the rights or preferences
of the preferred stock, such as the issuance of additional amounts or classes of
senior securities, the modification of the terms of the preferred stock, the
dissolution of the Corporation, or the payment of dividends by the Corporation
when preferred dividends are in arrears; (ii) the preferred stock represents an
essentially passive investment or financing device and does not otherwise
provide the holder with control over the Corporation; and (iii) the preferred
stock does not at the time entitle the holder, by statue, charter, or otherwise,
to select or to vote for the selection of directors of the Corporation.
Notwithstanding anything in the preceding two sentences, "Voting Stock" shall be
deemed to include preferred stock and other securities that, upon transfer or
otherwise, are convertible into Voting Stock or exercisable to acquire Voting
Stock where the holder of the stock, convertible security or right to acquire
Voting Stock has the preponderant economic risk in the underlying Voting Stock.
Securities immediately convertible into Voting Stock at the option of the holder
without payment of additional consideration shall be deemed to constitute the
Voting Stock into which they are convertible; other convertible securities and
rights to acquire Voting Stock shall not be deemed to vest the holder with the
preponderant economic risk in the underlying Voting Stock if the holder has paid
less than 50% of the consideration required to directly acquire the Voting Stock
and has no other economic interest in the underlying Voting Stock.
 
 
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         TWELFTH: The Mutual Holding Company may elect to convert to stock form
in accordance with applicable law and regulation (a "Conversion Transaction").
In a Conversion Transaction, the Mutual Holding Company will merge with and into
Investors Savings Bank (the "Bank"), with the Bank as the resulting entity, and
the depositors of the Bank will receive the right to subscribe for shares of
common stock of the Corporation. The additional shares of common stock of the
Corporation issued in the Conversion Transaction shall be sold at their
aggregate pro forma market value. At the sole discretion of the Board of
Directors of the Mutual Holding Company and the Corporation, a Conversion
Transaction may be effected in any other manner necessary to qualify the
Conversion Transaction as a tax-free reorganization under applicable federal and
state tax laws, provided such Conversion Transaction does not diminish the
rights and ownership interest of stockholders of the Corporation other than the
Mutual Holding Company ("Minority Stockholders"). In a Conversion Transaction,
Minority Stockholders, if any, will be entitled to maintain the same percentage
ownership interest in the Corporation immediately prior to the Conversion
Transaction, subject only to adjustment if required by federal or state law,
regulation or regulatory policy. If a Conversion Transaction does not occur, the
Mutual Holding Company will always own a majority of the Voting Stock of the
Corporation.
 
         THIRTEENTH: The Corporation reserves the right to amend or repeal any
provision contained in this Certificate of Incorporation in the manner
prescribed by the laws of the State of Delaware and all rights conferred upon
stockholders are granted subject to this reservation; provided, however, that,
notwithstanding any other provision of this Certificate of Incorporation or any
provision of law which might otherwise permit a lesser vote or no vote, but in
addition to any vote of the holders of any class or series of the stock of the
Corporation required by law or by this Certificate of Incorporation, the
affirmative vote of the holders of at least 80% 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 (after giving effect to the
provisions of Article FOURTH), voting together as a single class, shall be
required to amend or repeal this Article THIRTEENTH, Section C of Article
FOURTH, Sections C or D of Article FIFTH, Article SIXTH, Article SEVENTH,
Article NINTH or Article TENTH.
 
 
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