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                                                                     EXHIBIT 3.3


                           CERTIFICATE OF DESIGNATIONS

                                       of

                  SERIES A JUNIOR PARTICIPATING PREFERRED STOCK

                                       of

                         Internet Security Systems, Inc.

                         (Pursuant to Section 151 of the
                        Delaware General Corporation Law)

         Internet Security Systems, Inc., a corporation organized and existing
under the General Corporation Law of the State of Delaware (hereinafter called
the "Corporation"), hereby certifies that the following resolution was adopted
by the Board of Directors of the Corporation as required by Section 151 of the
General Corporation Law on July 11, 2002:

         RESOLVED, that pursuant to the authority granted to and vested in the
Board of Directors of this Corporation (hereinafter called the "Board of
Directors" or the "Board") in accordance with the provisions of the
Corporation's Restated Certificate of Incorporation (the "Certificate of
Incorporation") the Board of Directors hereby creates a new series of Preferred
Stock, par value $0.001 per share (the "Junior Preferred Stock"), of the
Corporation and hereby states the designation and number of shares of each such
series, and fixes the relative rights, preferences, and limitations of each such
series as follows:

         Section 1. Designation and Amount. The shares of such series shall be
designated as "Series A Junior Participating Preferred Stock" (the "Junior
Preferred Stock") and the number of shares constituting the Junior Preferred
Stock shall be one hundred twenty thousand (120,000). Such number of shares may
be increased or decreased by resolution of the Board of Directors; provided,
that no decrease shall reduce the number of shares of Junior Preferred Stock to
a number less than the number of shares then outstanding plus the number of
shares reserved for issuance upon the exercise of outstanding options, rights or
warrants or upon the conversion of any outstanding securities issued by the
Corporation convertible into Junior Preferred Stock.

         Section 2. Dividends and Distributions.

                  (A) Subject to the rights of the holders of any shares of any
         series of Preferred Stock (or any similar stock) ranking prior and
         superior to the Junior Preferred Stock with respect to dividends, the
         holders of shares of Junior Preferred Stock, in preference to the
         holders of the Common Stock, par value $0.001 per share (the "Common
         Stock"), of the Corporation, and of any other junior stock, shall be
         entitled to receive, when, as and if declared by the Board of Directors
         out of funds legally available for the purpose, quarterly dividends
         payable in cash on the first day of March, June, September and December
         in each year (each such date being referred to herein as a "Quarterly
         Dividend Payment Date"), commencing on the first Quarterly Dividend
         Payment Date after the first issuance of a share or fraction of a share
         of Junior Preferred Stock, in an amount per share (rounded to the
         nearest cent) equal to the greater of (a) $1.00 or (b) subject to the

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         provision for adjustment hereinafter set forth, 1,000 times the
         aggregate per share amount of all cash dividends, and 1,000 times the
         aggregate per share amount (payable in kind) of all non-cash dividends
         or other distributions, other than a dividend payable in shares of
         Common Stock or a subdivision of the outstanding shares of Common Stock
         (by reclassification or otherwise), declared on the Common Stock since
         the immediately preceding Quarterly Dividend Payment Date or, with
         respect to the first Quarterly Dividend Payment Date, since the first
         issuance of any share or fraction of a share of Junior Preferred Stock.
         If the Corporation shall at any time declare or pay any dividend on the
         Common Stock payable in shares of Common Stock, or effect a subdivision
         or combination or consolidation of the outstanding shares of Common
         Stock (by reclassification or otherwise than by payment of a dividend
         in shares of Common Stock) into a greater or lesser number of shares of
         Common Stock, then in each such case the amount to which holders of
         shares of Junior Preferred Stock were entitled immediately prior to
         such event under clause (b) of the preceding sentence shall be adjusted
         by multiplying such amount by a fraction, the numerator of which is the
         number of shares of Common Stock outstanding immediately after such
         event and the denominator of which is the number of shares of Common
         Stock that were outstanding immediately prior to such event.

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

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

         Section 3. Voting Rights. The holders of shares of Junior Preferred
Stock shall have the following voting rights:

                  (A) Subject to the provision for adjustment hereinafter set
         forth, each share of Junior Preferred Stock shall entitle the holder
         thereof to 1,000 votes on all matters


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         submitted to a vote of the stockholders of the Corporation. If the
         Corporation shall at any time declare or pay any dividend on the Common
         Stock payable in shares of Common Stock, or effect a subdivision or
         combination or consolidation of the outstanding shares of Common Stock
         (by reclassification or otherwise than by payment of a dividend in
         shares of Common Stock) into a greater or lesser number of shares of
         Common Stock, then in each such case the number of votes per share to
         which holders of shares of Junior Preferred Stock were entitled
         immediately prior to such event shall be adjusted by multiplying such
         number by a fraction, the numerator of which is the number of shares of
         Common Stock outstanding immediately after such event and the
         denominator of which is the number of shares of Common Stock that were
         outstanding immediately prior to such event.

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

                  (C) Except as set forth herein, or as otherwise provided by
         law, holders of Junior Preferred Stock shall have no other voting
         rights and their consent shall not be required (except to the extent
         they are entitled to vote with holders of Common Stock as set forth
         herein) for taking any corporate action.

         Section 4. Liquidation, Dissolution or Winding Up. Upon any
liquidation, dissolution or winding up of the Corporation, no distribution shall
be made (1) to the holders of shares of stock ranking junior (either as to
dividends or upon liquidation, dissolution or winding up) to the Junior
Preferred Stock unless, prior thereto, the holders of shares of Junior Preferred
Stock shall have received $1,000 per share, plus an amount equal to accrued and
unpaid dividends and distributions thereon, whether or not declared, to the date
of such payment, provided that the holders of shares of Junior Preferred Stock
shall be entitled to receive an aggregate amount per share, subject to the
provision for adjustment hereinafter set forth, equal to 1,000 times the
aggregate amount to be distributed per share to holders of shares of Common
Stock, or (2) to the holders of shares of stock ranking on a parity (either as
to dividends or upon liquidation, dissolution or winding up) with the Junior
Preferred Stock, except distributions made ratably on the Junior Preferred Stock
and all such parity stock in proportion to the total amounts to which the
holders of all such shares are entitled upon such liquidation, dissolution or
winding up. If the Corporation shall at any time declare or pay any dividend on
the Common Stock payable in shares of Common Stock, or effect a subdivision or
combination or consolidation of the outstanding shares of Common Stock (by
reclassification or otherwise than by payment of a dividend in shares of Common
Stock) into a greater or lesser number of shares of Common Stock, then in each
such case the aggregate amount to which holders of shares of Junior Preferred
Stock were entitled immediately prior to such event under the proviso in clause
(1) of the preceding sentence shall be adjusted by multiplying such amount by a
fraction the numerator of which is the number of shares of Common Stock
outstanding immediately after such event and the denominator of which is the
number of shares of Common Stock that were outstanding immediately prior to such
event.

         Section 5. Consolidation, Merger, etc. If the Corporation shall enter
into any consolidation, merger, combination or other transaction in which the
shares of Common Stock are exchanged for or changed into other stock or
securities, cash or any other property, then in any such case each share of
Junior Preferred Stock shall at the same time be similarly exchanged


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or changed into an amount per share, subject to the provision for adjustment
hereinafter set forth, equal to 1,000 times the aggregate amount of stock,
securities, cash or any other property (payable in kind), as the case may be,
into which or for which each share of Common Stock is changed or exchanged. If
the Corporation shall at any time declare or pay any dividend on the Common
Stock payable in shares of Common Stock, or effect a subdivision or combination
or consolidation of the outstanding shares of Common Stock (by reclassification
or otherwise than by payment of a dividend in shares of Common Stock) into a
greater or lesser number of shares of Common Stock, then in each such case the
amount set forth in the preceding sentence with respect to the exchange or
change of shares of Junior Preferred Stock shall be adjusted by multiplying such
amount by a fraction, the numerator of which is the number of shares of Common
Stock outstanding immediately after such event and the denominator of which is
the number of shares of Common Stock that were outstanding immediately prior to
such event.

         Section 6. Certain Restrictions.

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

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

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

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

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

         (B) The Corporation shall not permit any subsidiary of the Corporation
to purchase or otherwise acquire for consideration any shares of stock of the
Corporation unless the Corporation could, under paragraph (A) of this Section 6,
purchase or otherwise acquire such shares at such time and in such manner.


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         Section 7. Reacquired Shares. Any shares of Junior Preferred Stock
purchased or otherwise acquired by the Corporation in any manner whatsoever
shall be retired and canceled promptly after the acquisition thereof. All such
shares shall upon their cancellation become authorized but unissued shares of
Preferred Stock and may be reissued as part of a new series of Preferred Stock
subject to the conditions and restrictions on issuance set forth herein, in the
Certificate of Incorporation, or in any other Certificate of Designations
creating a series of Preferred Stock or any similar stock or as otherwise
required by law.

         Section 8. No Redemption. The shares of Junior Preferred Stock shall
not be redeemable.

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

         Section 10. Amendment. The Certificate of Incorporation shall not be
amended in any manner which would alter or change the powers, preferences or
special rights of the Junior Preferred Stock so as to affect them adversely
without the affirmative vote of the holders of at least two-thirds of the
outstanding Junior Preferred Stock.

         Section 11. Fractional Shares. The Junior Preferred Stock may be issued
in fractions of a share which shall entitle the holder, in proportion to such
holder's fractional shares, to exercise voting rights, receive dividends,
participate in distributions and to have the benefit of all other rights of
holders of the Junior Preferred Stock.

         IN WITNESS WHEREOF, this Certificate of Designations is executed on
behalf of the Corporation by its Chairman of the Board and attested by its
Assistant Secretary this 24th day of July 2002.


                                         /s/ Thomas E. Noonan
                                         ---------------------------------------
                                         Thomas E. Noonan, Chairman of the Board
Attest:

/s/ Sean Bowen
------------------------------------
Sean Bowen, Assistant Secretary


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