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                                                                     Exhibit 3.1

                                THIRD AMENDED AND
                    RESTATED CERTIFICATE OF INCORPORATION OF
                               ACTUATE CORPORATION
                             a Delaware corporation

                     (Pursuant to Sections 228, 242 and 245
                    of the Delaware General Corporation Law)

            Actuate Corporation, a corporation organized and existing under the
General Corporation Law of the State of Delaware (the "General Corporation Law")

            DOES HEREBY CERTIFY:

            FIRST: That the Corporation was originally incorporated on May 26,
1998, pursuant to the General Corporation Law under the name "Actuate Software
Corporation."

            SECOND: That the Board of Directors duly adopted resolutions
proposing to amend and restate the Certificate of Incorporation of the
Corporation, declaring said amendment and restatement to be advisable and in the
best interests of the Corporation and its stockholders, and authorizing the
appropriate officers of the Corporation to solicit the consent of the
stockholders therefor, which resolution setting forth the proposed amendment and
restatement is as follows:

            "RESOLVED, that the Certificate of Incorporation of the Corporation
be amended and restated in its entirety as follows:

                                    ARTICLE I

            The name of the corporation is Actuate Corporation (the
"Corporation").

                                   ARTICLE II

            The address of the registered office of the Corporation in the State
of Delaware is 15 East North Street, in the City of Dover, County of Kent. The
name of its registered agent at such address is Incorporating Services, Ltd.

                                  ARTICLE III

            The nature of the business or purposes to be conducted or promoted
is to engage in any lawful act or activity for which corporations may be
organized under the General Corporation Law of Delaware.

                                   ARTICLE IV

            The Corporation is authorized to issue two classes of stock to be
designated common stock ("Common Stock") and preferred stock ("Preferred
Stock"). The number of
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shares of Common Stock authorized to be issued is One Hundred Million
(100,000,000), par value $0.001 per share, and the number of shares of Preferred
Stock authorized to be issued is Five Million (5,000,000), par value $0.001 per
share.

            The Preferred Stock may be issued from time to time in one or more
series, without further stockholder approval. The Board of Directors is hereby
authorized, in the resolution or resolutions adopted by the Board of Directors
providing for the issue of any wholly unissued series of Preferred Stock, within
the limitations and restrictions stated in this Third Amended and Restated
Certificate of Incorporation (the "Restated Certificate"), to fix or alter the
dividend rights, dividend rate, conversion rights, voting rights, rights and
terms of redemption (including sinking fund provisions), the redemption price or
prices, and the liquidation preferences of any wholly unissued series of
Preferred Stock, and the number of shares constituting any such series and the
designation thereof, or any of them, and to increase or decrease the number of
shares of any series subsequent to the issue of shares of that series, but not
below the number of shares of such series then outstanding. In case the number
of shares of any series shall be so decreased, the shares constituting such
decrease shall resume the status that they had prior to the adoption of the
resolution originally fixing the number of shares of such series.

                                   ARTICLE V

            Except as otherwise provided in this Restated Certificate, in
furtherance and not in limitation of the powers conferred by statute, the Board
of Directors is expressly authorized to make, repeal, alter, amend and rescind
any or all of the Bylaws of the Corporation.

                                   ARTICLE VI

            The number of directors of the Corporation shall be fixed from time
to time by a bylaw or amendment thereof duly adopted by the Board of Directors.

                                  ARTICLE VII

            Elections of directors need not be by written ballot unless the
Bylaws of the Corporation shall so provide.

                                  ARTICLE VIII

            Except as otherwise provided in this Restated Certificate, any
action required or permitted to be taken by the stockholders of the Corporation
must be effected at an annual or special meeting of the stockholders of the
Corporation, and may not be effected by any consent in writing of such
stockholders.

                                   ARTICLE IX

            A director of the Corporation shall, to the fullest extent permitted
by the General Corporation Law as it now exists or as it may hereafter be
amended, not be personally liable to the Corporation or its stockholders for
monetary damages for breach of fiduciary duty as a


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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 that involve intentional misconduct or a knowing violation of
law, (iii) under Section 174 of the General Corporation Law, or (iv) for any
transaction from which the director derived any improper personal benefit. If
the General Corporation Law is amended, after approval by the stockholders of
this Article, to authorize corporation action further eliminating or limiting
the personal liability of directors, then the liability of a director of the
Corporation shall be eliminated or limited to the fullest extent permitted by
the General Corporation Law, as so amended.

            Any amendment, repeal or modification of this Article IX, or the
adoption of any provision of this Restated Certificate inconsistent with this
Article IX, by the stockholders of the Corporation shall not apply to or
adversely affect any right or protection of a director of the Corporation
existing at the time of such amendment, repeal, modification or adoption.

                                   ARTICLE X

            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 Restated Certificate, the
affirmative vote of the holders of a majority 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, voting together as a single class, shall
be required to amend or repeal the provisions of this Restated Certificate.

                                   ARTICLE XI

            To the fullest extent permitted by applicable law, the Corporation
is authorized to provide indemnification of (and advancement of expenses to)
agents of the Corporation (and any other persons to which General Corporation
Law permits the Corporation to provide indemnification) through bylaw
provisions, agreements with such agents or other persons, vote of stockholders
or disinterested directors or otherwise, in excess of the indemnification and
advancement otherwise permitted by Section 145 of the General Corporation Law,
subject only to limits created by applicable General Corporation Law (statutory
or non-statutory), with respect to actions for breach of duty to the
Corporation, its stockholders, and others.

            Any amendment, repeal or modification of the foregoing provisions of
this Article XI shall not adversely affect any right or protection of a
director, officer, agent, or other person existing at the time of, or increase
the liability of any director of the Corporation with respect to any acts or
omissions of such director, officer or agent occurring prior to, such amendment,
repeal or modification.

                                     * * * *

            THIRD: The foregoing amendment and restatement was approved by the
holders of the requisite number of shares of said corporation in accordance with
Section 228 of the General Corporation Law.

            FOURTH:That said amendment and restatement was duly adopted in
accordance with the provisions of Section 242 and 245 of the General Corporation
Law.


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      IN WITNESS WHEREOF, the undersigned has signed this Certificate this 10th
day of February, 2000.


                                           /s/ Nicolas Nierenberg
                                           -------------------------------------
                                           Nicolas Nierenberg
                                           President

ATTEST:


/s/ William P. Garvey
-------------------------------------
William P. Garvey
Secretary