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                                                                     EXHIBIT 3.1


                              AMENDED AND RESTATED
                          CERTIFICATE OF INCORPORATION
                                       OF
                                   RETEK INC.


                  RETEK INC., a Delaware corporation, hereby certifies as
follows:

                  1. The name of the corporation is Retek Inc. (the
"Corporation"). The date of filing of its original Certificate of Incorporation
with the Secretary of State of the State of Delaware was August 30, 1999. The
original name of the Corporation was Retek, Inc.

                  2. This Amended and Restated Certificate of Incorporation
amends and restates the provisions of the Certificate of Incorporation of the
Corporation and was duly adopted in accordance with the provisions of Sections
228, 242 and 245 of the General Corporation Law of the State of Delaware.

                  3. The text of the Certificate of Incorporation is hereby
amended and restated in its entirety to read as follows:

                                   ARTICLE I
                                      NAME

                  SECTION 1.01. Name. The name of the corporation is Retek Inc.
(the "Corporation").

                                   ARTICLE II
                                REGISTERED AGENT

                  SECTION 2.01. Agent. The address of the Corporation's
registered office in the State of Delaware is Corporation Trust Center, 1209
Orange Street, in the City of Wilmington, County of New Castle. The name of the
Corporation's registered agent at such address is The Corporation Trust Company.

                                  ARTICLE III
                                     PURPOSE

                  SECTION 3.01. Purpose. The purpose of the Corporation is to
engage in any lawful act or activity for which corporations may be organized
under the General Corporation Law of the State of Delaware as the same exists or
may hereafter be amended.

                                   ARTICLE IV
                                  CAPITAL STOCK

                  SECTION 4.01. Capital Stock. The total number of shares of all
classes of capital stock that the Corporation shall have the authority to issue
is 155,000,000 shares, of which (i) 150,000,000 shares shall be common stock,
par value $0.01 per share ("Common
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Stock"), and (ii) 5,000,000 shares shall be preferred stock, par value $0.01 per
share ("Preferred Stock").

                  Upon the effective date of the filing of this Amended and
Restated Certificate of Incorporation, each share of the Corporation's
outstanding capital stock shall be converted and reconstituted into 40,000
shares of Common Stock (the "Stock Split"). No further adjustment of any
preference or price set forth in this Article IV shall be made as a result of
this Stock Split.

                  SECTION 4.02. Common Stock. Each holder of Common Stock shall
have one vote on each matter submitted to a vote at a meeting of stockholders,
including the election of directors, for each share of Common Stock held of
record by such holder as of the record date for such meeting. Except as
otherwise required by law or provided in any resolution adopted by the
Corporation's Board of Directors (the "Board of Directors") with respect to any
series of Preferred Stock, the holders of shares of Common Stock will possess
all voting power, and holders of shares of Preferred Stock shall not be entitled
to receive notice of any meeting of stockholders at which they are not entitled
to vote. No provision herein should be interpreted as providing for cumulative
voting in the election of directors.

                  SECTION 4.03. Dividends and Distributions. Subject to any
preferential rights of any outstanding series of Preferred Stock created by the
Board of Directors from time to time, when, as and if dividends or distributions
are declared on outstanding shares of Common Stock, whether payable in cash, in
property or in securities of the Corporation, each holder of outstanding shares
of Common Stock shall be entitled to share ratably in such dividends and
distributions in proportion to the number of shares of Common Stock held by such
holder.

                  SECTION 4.04. Dissolution. Subject to any preferential rights
of any outstanding series of Preferred Stock created by the Board of Directors
from time to time, upon any liquidation, dissolution or winding up of the
Corporation, whether voluntary or involuntary, each holder of outstanding shares
of Common Stock shall be entitled to share ratably in the assets of the
Corporation to be distributed among the holders of shares of Common Stock in
proportion to the number of shares of Common Stock held by such holder.

                  SECTION 4.05. Preemptive Rights. The holders of shares of
Common Stock shall have no preemptive or preferential rights of subscription to
any shares of any class of capital stock of the Corporation or any securities
convertible into or exchangeable for shares of any class of capital stock of the
Corporation.

                  SECTION 4.06. Preferred Stock. Subject to the terms of any
contract to which the Corporation is bound, the Preferred Stock may be issued,
if so determined by the Board of Directors, either as a class without series or
from time to time in one or more series and with such designation for such class
or such series adopted by the Board of Directors. The Board of Directors in any
such resolution or resolutions is expressly authorized to state and express for
such class or each such series:

                  (a) Voting rights, if any, including, without limitation, the
authority to confer multiple votes per share, voting rights as to specified
matters or issues or, subject to the provisions of this Amended and Restated
Certificate of Incorporation, voting rights to be

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exercised either together with the holders of Common Stock as a single class, or
independently as a separate class;

                  (b) The rate per annum and the times at and conditions upon
which the holders of shares of such class or series shall be entitled to receive
dividends, the conditions and dates upon which such dividends shall be payable
and whether such dividends shall be cumulative or noncumulative, and, if
cumulative, the terms upon which such dividends shall be cumulative;

                  (c) Redemption, repurchase, retirement and sinking fund
rights, preferences and limitations, if any, the amount payable on shares of
such class or series in the event of such redemption, repurchase or retirement,
the terms and conditions of any sinking fund, the manner of creating such fund
or funds and whether any of the foregoing shall be cumulative or noncumulative;

                  (d) The rights to which the holders of the shares of such
class or series shall be entitled upon any voluntary or involuntary liquidation,
dissolution or winding up of the Corporation;

                  (e) The terms, if any, upon which the shares of such class or
series shall be convertible into or exchangeable for shares of stock of any
other class or classes or of any other series of the same or any other class or
classes, including the price or prices or the rate or rates of conversion or
exchange and the terms of adjustment, if any;

                  (f) Any other designations, preferences and relative,
participating, optional or other special rights and qualifications, limitations
or restrictions thereof insofar as they are not inconsistent with the provisions
of this Amended and Restated Certificate of Incorporation (as it may be amended
from time to time) and to the full extent now or hereafter permitted by the laws
of the State of Delaware; and

                  (g) All shares of Preferred Stock, if issued as a class
without series, or all shares of the Preferred Stock of any one series, if
issued in series, shall be identical to each other in all respects and shall
entitle the holders thereof to the same rights and privileges, except that
shares of any one series issued at different times may differ as to the dates
from which dividends thereon, if cumulative, shall be cumulative.

                                   ARTICLE V
                               BOARD OF DIRECTORS

                  SECTION 5.01. Business. The business and affairs of the
Corporation shall be managed by or under the direction of the Board of
Directors, which may exercise all the powers of the Corporation and do all such
lawful acts and things that are not conferred upon or reserved to the
stockholders or others by law, by this Amended and Restated Certificate of
Incorporation, by the Bylaws of the Corporation or by any contract to which the
Corporation is bound.

                  SECTION 5.02. Election. Election of directors need not be by
written ballot unless the Bylaws of the Corporation so provide.

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                  SECTION 5.03. General. The following provisions are inserted
for the management of the business and for the conduct of the affairs of the
Corporation, and for further definition, limitation and regulation of the powers
of its directors and stockholders:

                  (a) The Bylaws of the Corporation may be altered, amended or
repealed and new Bylaws may be adopted by the affirmative vote of directors
constituting not less than a majority of the total number of directors which the
Corporation would have if there were no vacancies on the Board of Directors.

                  (b) Prior to the first date on which HNC Software Inc., a
Delaware corporation ("HNC"), and/or its affiliates collectively cease to
beneficially own an aggregate of at least a majority of the then outstanding
shares of Common Stock (the "Trigger Date"), the Board of Directors shall
consist of seven (7) directors. After the Trigger Date, and subject to the
rights, if any, of holders of Preferred Stock the Board of Directors shall
consist of not less than three (3) and not more than ten (10) directors, the
exact number of directors to be determined as set forth in, or in the manner
provided in, the Bylaws of the Corporation. The directors, other than those (if
any) who may be elected by the holders of Preferred Stock voting as a separate
class, shall be divided, with respect to the time they severally hold office,
into three classes, designated Class I, Class II and Class III. Each class shall
consist, as nearly as possible, of one-third of the total number of directors
constituting the entire Board of Directors. The term of the initial Class I
directors shall terminate on the date of the 2000 annual meeting of
stockholders; the term of the initial Class II directors shall terminate on the
date of the 2001 annual meeting of stockholders; and the term of the initial
Class III directors shall terminate on the date of the 2002 annual meeting of
stockholders. At each annual meeting of stockholders, beginning with the 2000
annual meeting of stockholders, successors to the class of directors whose terms
expire at that annual meeting of stockholders shall be elected for a three year
term. The initial Class III directors shall be Ward Carey, Charles H. Gaylord,
Jr. and Alex W. Hart. If the number of directors is changed, any increase or
decrease shall be apportioned among the classes so as to maintain the number of
directors in each class as nearly equal as possible, but in no case will a
decrease in the number of directors shorten the term of any incumbent director.
A director shall hold office until the annual meeting of stockholders for the
year in which his or her term expires and until his or her successor shall be
elected and shall qualify, subject, however, to prior death, resignation,
retirement, disqualification or removal from office. Subject to the rights, if
any, of the holders of Preferred Stock or the terms of any contract to which the
Corporation is bound, any vacancy on the Board of Directors that results from an
increase in the number of directors and any other vacancy occurring on the Board
of Directors, howsoever resulting, may be filled only by a majority of the
remaining members of the Board of Directors, though less than a quorum, or by
the sole remaining director, and except as otherwise provided by law or the
terms of any contract to which the Corporation is bound, any such vacancy may
not be filled by the stockholders of the Corporation; provided, however, that
notwithstanding the foregoing, for so long as HNC has the right to nominate
persons for election to the Board of Directors of the Corporation pursuant to
the Corporate Rights Agreement referenced in Section 13.01 hereof, as such
agreement may be amended from time to time (such nominated persons being
hereinafter called "HNC Designees"), if a vacancy on the Corporation's Board of
Directors is caused by the death, disability, retirement, resignation or removal
for cause or otherwise of an HNC Designee, then HNC shall have the sole right to
nominate an individual to fill such vacancy on the Corporation's Board of
Directors. Any director elected in accordance with the preceding

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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 director's successor shall have been fully elected and qualified.

                  (c) Notwithstanding the foregoing, whenever the holders of any
one or more classes or series of Preferred Stock issued by the Corporation shall
have the right, voting separately by class or series, to elect directors at an
annual or special meeting of stockholders, the election, term of office, filling
of vacancies and other features of such directorships shall be governed by the
terms of this Amended and Restated Certificate of Incorporation (as it may be
amended from time to time) or the resolution or resolutions adopted by the Board
of Directors pursuant to Section 4.06 hereof, and such directors so elected
shall not be divided into classes pursuant to Section 5.03(b) unless expressly
provided by such terms.

                  (d) Advance notice of stockholder nominations for the election
of directors and of the proposal of business by stockholders shall be given in
the manner provided in the Bylaws of the Corporation, as amended and in effect
from time to time.

                  (e) Prior to the Trigger Date, any or all of the Directors may
be removed with or without cause at any time by either (i) the vote of the
holders of a majority of the outstanding shares of Common Stock then entitled to
vote at an election of Directors, or (ii) by written consent of the holders of
the Common Stock pursuant to Section 6.01 hereof. After the Trigger Date, any or
all of the Directors may be removed only with cause at any time by vote of the
holders of a majority of the Common Stock then entitled to vote at an election
of Directors.

                  (f) Notwithstanding anything contained in this Amended and
Restated Certificate of Incorporation to the contrary, after the Trigger Date,
the affirmative vote of the holders of at least 80% of the voting power of all
Voting Stock then outstanding, voting together as a single class, shall be
required to amend, repeal or adopt any provision inconsistent with this Article
V.

                                   ARTICLE VI
                               STOCKHOLDER ACTION

                  SECTION 6.01. Action By Written Consent. Prior to the Trigger
Date, any corporate action required or permitted to be taken at any annual or
special meeting of stockholders may be taken without a meeting, without prior
notice, if a consent or consents in writing, setting forth the action so taken,
shall be signed by the holders of the outstanding stock having not less than the
minimum number of votes that would be necessary to authorize or take such action
at a meeting at which all shares entitled to vote thereon were present and voted
and shall be delivered to the Corporation (either by hand or by certified or
registered mail, return receipt requested) at its registered office in the State
of Delaware or its principal place of business, or to an officer or agent of the
Corporation having custody of the book in which proceedings of meetings of
stockholders are recorded; provided, however, that effective as of and after the
Trigger Date, unless otherwise required by applicable law, any corporate action
required or permitted to be taken at any annual or special meeting of
stockholders may be taken only at a duly called annual or special meeting of
stockholders and may not be taken by written consent in lieu of such a meeting.

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                  SECTION 6.02. Special Meetings. Effective as of and after the
Trigger Date, unless otherwise prescribed by law and subject to any preferential
rights of any outstanding series of Preferred Stock created by the Board of
Directors from time to time, special meetings of the stockholders of the
Corporation for any purpose or purposes may be called at any time by the
Chairman of the Board of Directors, the President or, at the request in writing
of a majority of the members of the Board of Directors, any officer of the
Corporation, and effective as of and after the Trigger Date, any power of the
stockholders of the Corporation to call a special meeting is specifically
denied, provided, however, that prior to the Trigger Date, the Corporation shall
call a special meeting of the stockholders of the Corporation promptly upon the
request of HNC or any of its affiliates (other than the Corporation or any
subsidiary of the Corporation), in each case if such entity is a stockholder of
the Corporation.

                  SECTION 6.03. Amendment. Notwithstanding anything contained in
this Amended and Restated Certificate of Incorporation to the contrary, after
the Trigger Date, the affirmative vote of the holders of at least 80% of the
voting power of all Voting Stock then outstanding, voting together as a single
class, shall be required to amend, repeal or adopt any provision inconsistent
with this Article VI.

                                  ARTICLE VII
                                 INDEMNIFICATION

                  SECTION 7.01. Indemnification. (a) The Corporation shall
indemnify any person who was or is a party or is threatened to be made a party
to any threatened, pending or completed action, suit or proceeding, whether
civil, criminal, administrative or investigative (other than an action by or in
the right of the Corporation) by reason of the fact that he is or was a
director, officer, employee or agent of the Corporation, or is or was serving at
the request of the Corporation as a director, officer, employee or agent of
another corporation, partnership, joint venture, trust or other enterprise,
against expenses (including attorneys' fees), judgments, fines and amounts paid
in settlement actually and reasonably incurred by him in connection with such
action, suit or proceeding if he acted in good faith and in a manner he
reasonably believed to be in, or not opposed to, the best interests of the
Corporation, and, with respect to any criminal action or proceeding, had no
reasonable cause to believe his conduct was unlawful. The termination of any
action, suit or proceeding by judgment, order, settlement, conviction, or upon a
plea of nolo contendere or its equivalent, shall not, of itself, create a
presumption that the person did not act in good faith and in a manner which he
reasonably believed to be in or not opposed to the best interests of the
Corporation, and, with respect to any criminal action or proceeding, had
reasonable cause to believe that his conduct was unlawful.

                  (b) The Corporation shall indemnify any person who was or is a
party or is threatened to be made a party to any threatened, pending or
completed action or suit by or in the right of the Corporation to procure a
judgment in its favor by reason of the fact that he is or was a director,
officer, employee or agent of the Corporation, or is or was serving at the
request of the Corporation as a director, officer, employee or agent of another
corporation, partnership, joint venture, trust or other enterprise against
expenses (including attorneys' fees) actually and reasonably incurred by him in
connection with the defense or settlement of such action or suit if he acted in
good faith and in a manner he reasonably believed to be in or not opposed to the
best interests of the Corporation and except that no indemnification shall be
made in respect of any

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claim, issue or matter as to which such person shall have been adjudged to be
liable to the Corporation unless and only to the extent that the Court of
Chancery of the State of Delaware or the court in which such action or suit was
brought shall determine upon application that, despite the adjudication of
liability but in view of all the circumstances of the case, such person is
fairly and reasonably entitled to indemnity for such expenses which the Court of
Chancery or such other court shall deem proper.

                  (c) To the extent that a present or former director, officer,
employee or agent of the Corporation has been successful on the merits or
otherwise in defense of any action, suit or proceeding referred to in Section
7.01(a) and (b) hereof, or in defense of any claim, issue or matter therein, he
shall be indemnified against expenses (including attorneys' fees) actually and
reasonably incurred by him in connection therewith.

                  (d) Any indemnification under Section 7.01(a) and (b) hereof
(unless ordered by a court) shall be made by the Corporation only as authorized
in the specific case upon a determination that indemnification of the present or
former director, officer, employee or agent is proper in the circumstances
because he has met the applicable standard of conduct set forth in Section
7.01(a) and (b) hereof. Such determination shall be made with respect to a
person who is a director or officer at the time of such determination, (i) by a
majority vote of the directors who are not parties to such action, suit or
proceeding, even though less than a quorum, or (ii) by a committee of such
directors designated by majority vote of such directors, even though less than
quorum, or (iii) if there are no such directors, or if such directors so direct,
by independent legal counsel in a written opinion, or (iv) by the stockholders
of the Corporation.

                  (e) Expenses (including attorneys' fees) incurred by an
officer or director in defending any civil, criminal, administrative or
investigative action, suit or proceeding may be paid by the Corporation in
advance of the final disposition of such action, suit or proceeding upon receipt
of an undertaking by or on behalf of such director or officer to repay such
amount if it shall ultimately be determined that he is not entitled to be
indemnified by the Corporation pursuant to this Article VII. Such expenses
(including attorneys' fees) incurred by former directors and officers or other
employees and agents may be so paid upon such terms and conditions, if any, as
the Corporation deems appropriate.

                  (f) The indemnification and advancement of expenses provided
by, or granted pursuant to, other Sections of this Article VII shall not be
deemed exclusive of any other rights to which those seeking indemnification or
advancement of expenses may be entitled under any law, bylaw, agreement, vote of
stockholders or disinterested directors or otherwise, both as to action in an
official capacity and as to action in another capacity while holding such
office.

                  (g) For purposes of this Article VII, references to "the
Corporation" shall include, in addition to the resulting corporation, any
constituent corporation (including any constituent of a constituent) absorbed in
a consolidation or merger which, if its separate existence had continued, would
have had power and authority to indemnify its directors, officers, employees or
agents so that any person who is or was a director, officer, employee or agent
of such constituent corporation, or is or was serving at the request of such
constituent corporation as a director, officer, employee or agent of another
corporation, partnership, joint venture, trust or other enterprise, shall stand
in the same position under the provisions of this Article VII with

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respect to the resulting or surviving corporation as he would have with respect
to such constituent corporation if its separate existence had continued.

                  (h) For purposes of this Article VII, references to "other
enterprises" shall include employee benefit plans; references to "fines" shall
include any excise taxes assessed on a person with respect to an employee
benefit plan; and references to "serving at the request of the Corporation"
shall include any service as a director, officer, employee or agent of the
Corporation which imposes duties on, or involves service by, such director,
officer, employee or agent with respect to any employee benefit plan, its
participants, or beneficiaries; and a person who acted in good faith and in a
manner he reasonably believed to be in the interest of the participants and
beneficiaries of an employee benefit plan shall be deemed to have acted in a
manner "not opposed to the best interests of the Corporation" as referred to in
this Article VII.

                  (i) The indemnification and advancement of expenses provided
by, or granted pursuant to, this Article VII shall, unless otherwise provided
when authorized or ratified, continue as to a person who has ceased to be a
director, officer, employee or agent and shall inure to the benefit of the
heirs, executors and administrators of such a person.

                  SECTION 7.02. Insurance for Indemnification. The Corporation
shall have the power to purchase and maintain insurance on behalf of any person
who is or was a director, officer, employee or agent of the Corporation, or is
or was serving at the request of the Corporation as a director, officer,
employee or agent of another corporation, partnership, joint venture, trust or
other enterprise, against any liability asserted against such person and
incurred by such person in any such capacity, or arising out of such person's
status as such, whether or not the Corporation has the power to indemnify such
person against such liability under this Article VII or the provisions of
Section 145 of the General Corporation Law of the State of Delaware.

                                  ARTICLE VIII
                                     BYLAWS

                  SECTION 8.01. Amendment of Bylaws. The Bylaws of the
Corporation may be altered, amended or repealed and new Bylaws may be adopted
(i) at any annual or special meeting of stockholders or, to the extent permitted
hereby, the written consent of the stockholders, by the affirmative vote of the
holders of a majority of the voting power of the outstanding Common Stock
entitled to vote on that matter, provided, however, that any proposed
alteration, amendment or repeal of, or the adoption of any Bylaw inconsistent
with, Sections 2.02, 2.04, 2.11, 3.02, 3.04 or 3.05 of the Bylaws, by the
stockholders shall require the affirmative vote of the holders of at least 80%
of the voting power of all Common Stock then outstanding, voting together as a
single class, or (ii) by the affirmative vote of directors constituting not less
than a majority of the total number of directors which the Corporation would
have if there were no vacancies.

                  Notwithstanding anything contained in this Amended and
Restated Certificate of Incorporation to the contrary, the affirmative vote of
the holders of at least 80% of the outstanding shares of Common Stock shall be
required to amend, repeal or adopt any provision inconsistent with this Article
VIII.

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                                   ARTICLE IX
                      LIMITATION ON LIABILITY OF DIRECTORS

                  SECTION 9.01. Limitation on Liability. A director of the
Corporation shall not be personally liable to the Corporation or its
stockholders for monetary damages for breach of fiduciary duty as a director,
except for liability (i) for any breach of the director's duty of loyalty to the
Corporation or its stockholders, (ii) for acts or omissions not in good faith or
which involve intentional misconduct or a knowing violation of law, (iii) under
Section 174 of the Delaware General Corporation Law, or (iv) for any transaction
from which the director derived an improper personal benefit.

                                   ARTICLE X
                             CORPORATE OPPORTUNITIES

                  SECTION 10.01. Purpose. In anticipation that the Corporation
will cease to be a wholly-owned subsidiary of HNC, but that HNC will remain a
substantial stockholder of the Corporation, and in anticipation that the
Corporation and HNC may engage in the same or similar activities or lines of
business and have an interest in the same areas of corporate opportunities, and
in recognition of the benefits to be derived by the Corporation through its
continued contractual, corporate and business relations with HNC (including
possible service of officers and directors of HNC as officers and/or directors
of the Corporation), the provisions of this Article are set forth to regulate
and define the conduct of certain affairs of the Corporation as they may involve
HNC and its officers and directors, and the powers, rights, duties and
liabilities of the Corporation and its officers, directors and stockholders in
connection therewith.

                  SECTION 10.02. No Duty to Refrain. HNC shall have no duty to
refrain from engaging in the same or similar activities or lines of business as
the Corporation, and neither HNC nor any officer or director thereof (except as
provided in Section 10.03 below) shall be liable for breach of any fiduciary
duty by reason of any such activities of HNC. In the event that HNC acquires
knowledge of a potential transaction or matter which may be a corporate
opportunity for both HNC and the Corporation, HNC shall have no duty to
communicate or offer such corporate opportunity to the Corporation and shall not
be liable for breach of any fiduciary duty as a stockholder of the Corporation
by reason of the fact that HNC pursues or acquires such corporate opportunity
for itself, directs such corporate opportunity to another person, or does not
communicate information regarding such corporate opportunity to the Corporation.

                  SECTION 10.03. Corporate Opportunities. In the event that a
director or officer of the Corporation who is also a director or officer of HNC
acquires knowledge of a potential transaction or matter which may be a corporate
opportunity for both the Corporation and HNC, such director or officer of the
Corporation shall have fully satisfied and fulfilled the fiduciary duty of such
director or officer to the Corporation and its stockholders with respect to such
corporate opportunity, if such director or officer acts in a manner consistent
with the following policy: (i) A corporate opportunity offered to any person who
is an officer of the Corporation, and who is also a director but not an officer
of HNC, shall belong to the Corporation; (ii) a corporate opportunity offered to
any person who is a director but not an officer of the Corporation, and who is
also a director or officer of HNC shall belong to the Corporation if such
opportunity is expressly offered to such person in writing solely in his or her

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capacity as a director of the Corporation, and otherwise shall belong to HNC;
and (iii) a corporate opportunity offered to any person who is an officer of
both the Corporation and HNC shall belong to the Corporation if such opportunity
is expressly offered to such person in writing solely in his or her capacity as
an officer of the Corporation, and otherwise shall belong to HNC.

                  SECTION 10.04. Successors. Any person purchasing or otherwise
acquiring any interest in shares of the capital stock of the Corporation shall
be deemed to have notice of and to have consented to the provisions of this
Article.

                  SECTION 10.05. Definitions. For purposes of this Article only:

                  (a) A director of the Corporation who is Chairman of the Board
of Directors of the Corporation or of a committee thereof shall not be deemed to
be an officer of the Corporation by reason of holding such position (without
regard to whether such position is deemed an office of the Corporation under the
Bylaws of the Corporation), unless such person is a full-time employee of the
Corporation; and

                  (b) (1) The term "Corporation" shall mean the Corporation and
all corporations, partnerships, joint ventures, associations and other entities
in which the Corporation beneficially owns (directly or indirectly) 50% or more
of the outstanding voting stock, voting power, partnership interests or similar
voting interests, and (2) the term "HNC," for the purpose of this Article only,
shall mean HNC and all corporations, partnerships, joint ventures, associations
and other entities (other than the Corporation, defined in accordance with
clause (1) of this paragraph Section 10.05(b)) in which HNC beneficially owns
(directly or indirectly) 50% or more of the outstanding voting stock, voting
power, partnership interests or similar voting interests.

                  SECTION 10.06. Expiration. Notwithstanding anything in this
Amended and Restated Certificate of Incorporation to the contrary, (i) the
foregoing provisions of this Article shall expire on the date that HNC ceases to
own beneficially Common Stock representing at least 25% of the total voting
power of all classes of outstanding Common Stock of the Corporation and no
person who is a director or officer of the Corporation is also a director or
officer of HNC; and (ii) in addition to any vote of the stockholders required by
this Amended and Restated Certificate of Incorporation, until the time that HNC
ceases to own beneficially Common Stock representing at least 25% of the total
voting power of all classes of outstanding Common Stock of the Corporation, the
affirmative vote of the holders of more than 80% of the total voting power of
all classes of outstanding Common Stock of the Corporation shall be required to
alter, amend or repeal in a manner adverse to the interests of HNC, or adopt any
provision adverse to the interests of HNC and inconsistent with, any provision
of this Article. Neither the alteration, amendment or repeal of this Article nor
the adoption of any provision of this Amended and Restated Certificate of
Incorporation inconsistent with this Article shall eliminate or reduce the
effect of this Article in respect of any matter occurring, or any cause of
action, suit or claim that, but for this Article, would accrue or arise, prior
to such alteration, amendment, repeal or adoption.


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                                   ARTICLE XI
         AMENDMENT OF AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

                  SECTION 11.01. Amendment. Subject to any contract to which the
Corporation is bound, the Corporation reserves the right to amend, alter,
restate, change or repeal an provision contained in this Amended and Restated
Certificate of Incorporation, in the manner now or hereafter prescribed by the
laws of the State of Delaware, and all rights of the stockholders herein are
granted subject to this reservation.

                                  ARTICLE XII
                              BUSINESS COMBINATIONS

                  SECTION 12.01. Applicability of Section 203. The Corporation
shall not be and hereby elects not to be governed by Section 203 of the General
Corporation Law of the State of Delaware, as in effect on the date this
provision becomes effective or as it may hereafter be amended ("Section 203"),
until such time as HNC (or any corporation or other entity into which HNC has
merged or consolidated in a statutory merger or consolidation) owns (as defined
by Section 203) less than fifteen percent (15%) of the Corporation's outstanding
voting stock (as defined in Section 203).

                                  ARTICLE XIII
                                  MISCELLANEOUS

                  SECTION 13.01. Contracts References. Whenever in this Amended
and Restated Certificate of Incorporation the phrase "any contract to which the
Corporation is bound" or a similar phrase is used, the reference therein to a
contract to which the Corporation is bound shall specifically include, without
limitation, that certain Separation Agreement entered into among the
Corporation, HNC and Retek Information Systems, Inc., as such may be amended
from time to time, and that certain Corporate Rights Agreement among the
Corporation, HNC and Retek Information Systems, Inc., as such may be amended
from time to time, and the contents of such contracts shall be deemed to have
been incorporated herein by reference.


<PAGE>   12

                                       12


                  This Amended and Restated Certificate of Incorporation shall
become effective at 8:00 a.m. (Wilmington, Delaware time), November 23, 1999.

                  IN WITNESS WHEREOF, RETEK INC. has caused this certificate to
be signed by Gordon Masson, its President, and attested by Gregory A. Effertz,
its Secretary, on this twenty-second day of November, 1999.

                                           RETEK INC.


                                           By: /s/ John Buchanan
                                              -------------------------
                                              Name:  John Buchanan
                                              Title: Chairman and Chief
                                                     Executive Officer


ATTEST:

/s/ Gregory A. Effertz
--------------------------
Name:   Gregory A. Effertz
Title:  Secretary