EXHIBIT 3.1
 
                           THIRD AMENDED AND RESTATED
                          CERTIFICATE OF INCORPORATION
                                       OF
                         INTERNATIONAL STEEL GROUP INC.
 
 
         International Steel Group Inc. (the "Company"), a corporation organized
and existing under and by virtue of the General Corporation Law of the State of
Delaware, does hereby certify:
 
         1. The current name of the Company is International Steel Group Inc.
The original Certificate of Incorporation of the Company was filed with the
Secretary of State of the State of Delaware on February 22, 2002 and the
original name of the Company was WLR Acquisition Corp. On March 22, 2002, a
Certificate of Amendment of Certificate of Incorporation was filed to change the
original name of the Company to "International Steel Group Inc." The Company
filed a Certificate of Correction Filed to Correct a Certain Error in the
Certificate of Amendment of the Certificate of Incorporation with the Secretary
of State of the State of Delaware on March 28, 2002. On April 10, 2002, an
Amended and Restated Certificate of Incorporation was filed with the Secretary
of State of the State of Delaware. On May 5, 2003, the Second Amended and
Restated Certificate of Incorporation was filed with the Secretary of State of
the State of Delaware.
 
         2. By unanimous written consent of the Board of Directors of the
Company, a resolution was duly adopted, pursuant to Sections 141(f), 242 and 245
of the General Corporation Law of the State of Delaware, setting forth a Third
Amended and Restated Certificate of Incorporation of the Company and declaring
the enactment and filing of said Third Amended and Restated Certificate of
Incorporation with the Secretary of State of the State of Delaware advisable.
 
         3. The stockholders of the Company duly approved said proposed Third
Amended and Restated Certificate of Incorporation by written consent in
accordance with Sections 228, 242 and 245 of the General Corporation Law of the
State of Delaware.
 
         4. The resolution setting forth the Third Amended and Restated
Certificate of Incorporation is as follows:
 
                  RESOLVED: That the Second Amended and Restated Certificate of
         Incorporation of the Corporation be and hereby is amended and restated
         in its entirety so that the same shall read as follows:
 
                                    ARTICLE I
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                  The name of the corporation is International Steel Group Inc.
         (the "Company").
 
                                   ARTICLE II
                                   ----------
 
         The address of the Company's registered office in the State of Delaware
is 2711 Centerville Road, Suite 400, City of Wilmington, County of New Castle,
Delaware 19808. The name of the Company's registered agent at such address is
Corporation Service Company.
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                                   ARTICLE III
                                   -----------
 
         The purpose of the Company is to engage in any lawful act or activity
for which corporations may be organized under the Delaware General Corporation
Law.
 
                                   ARTICLE IV
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         Section 1. Authorized Capital Stock. The Company is authorized to issue
three classes of capital stock, designated Common Stock, Class B Common Stock
and Preferred Stock. The total number of shares of capital stock that the
Company is authorized to issue is 367,000,000 shares, consisting of 350,000,000
shares of Common Stock, par value of one cent ($.01) per share, 7,000,000 shares
of Class B Common Stock, par value of one cent ($.01) per share, and 10,000,000
shares of Preferred Stock, par value of one cent ($.01) per share.
 
         Section 2. Preferred Stock. The Preferred Stock may be issued in one or
more series. The Board of Directors of the Company (the "Board") is hereby
authorized to issue the shares of Preferred Stock in such series and to fix from
time to time before issuance the number of shares to be included in any such
series and the designation, relative powers, preferences, rights and
qualifications, limitations or restrictions of such series. The authority of the
Board with respect to each such series will include, without limiting the
generality of the foregoing, the determination of any or all of the following:
 
                  (a) the number of shares of any series and the designation to
         distinguish the shares of such series from the shares of all other
         series;
 
                  (b) the voting powers, if any, and whether such voting powers
         are full or limited in such series;
 
                  (c) the extent, if any, to which the holders of the shares of
         such series shall be entitled to vote as a class or otherwise with
         respect to the election of the directors or otherwise;
 
                  (d) the redemption provisions, if any, applicable to such
         series, including the redemption price or prices to be paid;
 
                  (e) whether dividends, if any, will be cumulative or
         noncumulative, the dividend rate of such series, and the dates and
         preferences of dividends on such series;
 
                  (f) the rights of such series upon the voluntary or
         involuntary dissolution of, or upon any distribution of the assets of,
         the Company;
 
                  (g) the provisions, if any, pursuant to which the shares of
         such series are convertible into, or exchangeable for, shares of any
         other class or classes or of any other series of the same or any other
         class or classes of stock, or any other security, of the Company or any
         other corporation or other entity and the rates or other determinants
         of conversion or exchange applicable thereto;
 
                  (h) the right, if any, to subscribe for or to purchase any
         securities of the Company or any other corporation or other entity;
 
                  (i) the provisions, if any, of a sinking fund applicable to
         such series; and
 
 
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                  (j) any other relative, participating, optional or other
         special powers, preferences or rights and qualifications, limitations
         or restrictions thereof;
 
all as may be determined from time to time by the Board and stated or expressed
in the resolution or resolutions providing for the issuance of such Preferred
Stock (collectively, a "Preferred Stock Designation").
 
         Section 3. Common Stock. Subject to the rights of the holders of any
series of Preferred Stock, the holders of Common Stock will be entitled to one
vote on each matter stockholders are entitled to vote under applicable law and
each matter submitted to a vote at a meeting of stockholders for each share of
Common Stock held of record by such holder as of the record date for such
meeting.
 
         Section 4. Class B Common Stock. Except as specified in this Article
IV, Section 4, the Class B Common Stock is identical in all respects to the
Common Stock and shall constitute, together with the Common Stock, a single
class of stock and shall vote together with the Common Stock as a single class
except as otherwise provided by law. The Company may not undertake any action of
the type set forth within the definition of Extraordinary Common Stock Event
(set forth below) unless the same action is taken with respect to both the
Common Stock and the Class B Common Stock.
 
                  (a) Upon the consummation of a sale of Common Stock by the
         Company pursuant to a bona fide underwritten public offering pursuant
         to an effective registration statement under the Securities Act of 1933
         (an "IPO"), each issued and outstanding share of Class B Common Stock
         shall automatically convert into the number of fully paid and
         nonassessable shares of Common Stock at the Conversion Ratio without
         any action by the holders thereof, such shares of Class B Common Stock
         shall automatically be cancelled and shall cease to exist, and no more
         shares of Class B Common Stock may be issued.
 
                  The "Conversion Ratio" means (i) $92,500 per share (the
         "Purchase Price") divided by (ii) the product of (x) the price per
         share paid by the public in the IPO multiplied by (y) 0.7, in any case
         as the Conversion Ratio may be adjusted from time to time in accordance
         with subsection (b) of this Article IV, Section 4.
 
                  (b) Upon the happening of an Extraordinary Common Stock Event
         (as hereinafter defined), the Conversion Ratio for the Class B Common
         Stock shall, simultaneously with the happening of such Extraordinary
         Common Stock Event, be adjusted by dividing the then applicable
         Purchase Price by a fraction, the numerator of which shall be the
         number of shares of Class B Common Stock outstanding immediately after
         such Extraordinary Common Stock Event and the denominator of which
         shall be the number of shares of Class B Common Stock outstanding
         immediately prior to such Extraordinary Common Stock Event, and the
         quotient so obtained shall thereafter be deemed the Purchase Price. The
         Conversion Ratio for the Class B Common Stock shall be readjusted in
         the same manner upon the happening of any successive Extraordinary
         Common Stock Event.
 
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                  "Extraordinary Common Stock Event" shall mean (A) the issue of
         additional shares of Common Stock and Class B Common Stock as a
         dividend or other distribution on outstanding shares of Common Stock
         and Class B Common Stock, respectively, (B) a stock split or
         subdivision of outstanding shares of Common Stock and Class B Common
         Stock into a greater number of shares of Common Stock and Class B
         Common Stock, respectively, (C) a combination or reverse stock split of
         outstanding shares of Common Stock and Class B Common Stock into a
         smaller number of shares of Common Stock and Class B Common Stock,
         respectively, or (D) any similar event.
 
                  (c) All issued and outstanding shares of Class B Common Stock
         shall be converted automatically into shares of Common Stock as
         provided in subsection (a) of this Article IV, Section 4 whether or not
         the certificates representing such shares of Class B Common Stock are
         surrendered to the Company or its transfer agent.
 
                  (d) In the event that (i) in connection with the distribution
         by any holder of Class B Common Stock of any shares of Class B Common
         Stock pursuant to a plan of liquidation or a plan of reorganization
         (each as defined under chapter 11 of the Bankruptcy Code, 11 U.S.C.
         ss.ss.101-1330), any fractional share of Class B Common Stock is
         created and (ii) the IPO shall not have occurred prior to December 15
         of the calendar year in which such distribution occurred, the Company
         shall have the right to eliminate such fractional share by purchasing
         such fractional share at a price equal to the product of (A) the then
         applicable Purchase Price multiplied by (B) the relevant fraction.
 
                  (e) In the event that upon the automatic conversion of Class B
         Common Stock into Common Stock as contemplated above, any fractional
         share of Common Stock is created, the Company shall have the right to
         eliminate any such fractional share at or about the time of such
         automatic conversion by purchasing any such fractional share for a
         price equal to the product of (A) the price per share paid by the
         public in the IPO, multiplied by (B) the relevant fraction.
 
                                    ARTICLE V
                                    ---------
 
         The Board may make, amend, and repeal the Bylaws of the Company. Any
Bylaw made by the Board under the powers conferred hereby may be amended or
repealed by the Board (except as specified in any such Bylaw so made or amended)
or by the stockholders in the manner provided in this Third Amended and Restated
Certificate of Incorporation and the Bylaws of the Company. Notwithstanding the
foregoing and anything contained in this Third Amended and Restated Certificate
of Incorporation or the Bylaws to the contrary, the Bylaws may not be amended or
repealed by the stockholders, and no provision inconsistent therewith may be
adopted by the stockholders, without the affirmative vote of the holders of at
least 80% of the voting power of the outstanding Voting Stock (as defined
below), voting together as a single class. The Company may in its Bylaws confer
powers upon the Board in addition to the foregoing and in addition to the powers
and authorities expressly conferred upon the Board by applicable law. For the
purposes of this Third Amended and Restated Certificate of Incorporation,
"Voting Stock" means stock of the Company of any class or series entitled to
vote generally in the election of the directors of the Board (the "Directors").
Notwithstanding anything contained in this Third Amended and Restated
Certificate of Incorporation to the contrary, the affirmative vote of the
holders of at least 80% of the voting power of the
 
 
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outstanding Voting Stock, voting together as a single class, is required to
amend or repeal, or to adopt any provisions inconsistent with, this Article V.
 
                                   ARTICLE VI
                                   ----------
 
         Subject to the rights of the holders of any series of Preferred Stock:
 
                  (a) any action required or permitted to be taken by the
         stockholders of the Company must be effected at a duly called annual or
         special meeting of stockholders of the Company and may not be effected
         by any consent in writing of such stockholders; and
 
                  (b) special meetings of stockholders of the Company may be
         called by the Chairman of the Board (the "Chairman"), the Chief
         Executive Officer of the Company (the "Chief Executive Officer"), the
         President of the Company (the "President") or the Secretary of the
         Company (the "Secretary") within 10 calendar days after receipt of the
         written request of a majority of the total number of Directors that the
         Company would have if there were no vacancies (the "Whole Board").
 
At any annual meeting or special meeting of stockholders of the Company, only
such business will be conducted or considered as has been brought before such
meeting in the manner provided in the Bylaws of the Company. Notwithstanding
anything contained in this Third Amended and Restated Certificate of
Incorporation to the contrary, the affirmative vote of the holders of at least
80% of the voting power of the outstanding Voting Stock, voting together as a
single class, will be required to amend or repeal, or to adopt any provision
inconsistent with, this Article VI.
 
                                   ARTICLE VII
                                   -----------
 
         Section 1. Number, Election, and Terms of Directors. Subject to the
rights, if any, of the holders of any series of Preferred Stock to elect
additional Directors under circumstances specified in a Preferred Stock
Designation, the number of the Directors constituting the Board shall be fixed
from time to time by, or in the manner provided in, the Bylaws of the Company.
The Directors, other than those who may be elected by the holders of any series
of Preferred Stock, will be classified with respect to the time for which they
severally hold office into three classes, as nearly equal in number as possible,
designated Class I, Class II, and Class III. Directors shall be assigned to each
class in accordance with a resolution or resolutions adopted by the Board. The
Directors first appointed to Class I will hold office for a term expiring at the
annual meeting of stockholders to be held in 2004; the Directors first appointed
to Class II will hold office for a term expiring at the annual meeting of
stockholders to be held in 2005; and the Directors first appointed to Class III
will hold office for a term expiring at the annual meeting of stockholders to be
held in 2006, with the members of each class to hold office until their
successors are elected and qualified or until their earlier resignation,
retirement, removal or death. Subject to the rights, if any, of the holders of
any series of Preferred Stock, any vacancy on the Board that results from an
increase in the number of directors may be filled by a majority of the Board
then in office, provided that a quorum is present, and any other vacancy
occurring on the Board may be filled by a majority of the Board then in office,
even if less than a quorum, or by a sole remaining director. If the number of
directors which shall constitute the whole
 
 
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Board of the Company 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, and any additional director of any class elected to
fill a vacancy resulting from an increase in such class shall hold office for a
term that shall coincide with the remaining term of that class, but in no case
shall a decrease in such number of directors shorten the term of any incumbent
director. Any director elected to fill a vacancy not resulting from an increase
in the number of directors shall have the same remaining term as that of his
predecessor. At each succeeding annual meeting of the stockholders of the
Company, the successors to the class of Directors whose term expires at that
meeting will be elected by plurality vote of all votes cast at such meeting to
hold office for a term expiring at the annual meeting of stockholders held in
the third year following the year of their election. Subject to the rights, if
any, of the holders of any series of Preferred Stock to elect additional
Directors under circumstances specified in a Preferred Stock Designation,
Directors may be elected by the stockholders only at an annual meeting of
stockholders. Election of Directors of the Company need not be by written ballot
unless requested by the Chairman or by the holders of a majority of the Voting
Stock present in person or represented by proxy at a meeting of the stockholders
at which Directors are to be elected. If authorized by the Board, such
requirement of written ballot shall be satisfied by a ballot submitted by
electronic transmission, provided that any such electronic transmission must
either set forth or be submitted with information from which it can be
determined that the electronic transmission was authorized by the stockholder or
proxy holder.
 
         Section 2. Removal. Subject to the rights, if any, of the holders of
any series of Preferred Stock to elect additional Directors under circumstances
specified in a Preferred Stock Designation, any Director may be removed from
office by the stockholders only for cause and only in the manner provided in
this Article VII, Section 2. At any annual meeting or special meeting of the
stockholders, the notice of which states that the removal of a Director or
Directors is among the purposes of the meeting, the affirmative vote of the
holders of at least 80% of the voting power of the outstanding Voting Stock,
voting together as a single class, may remove such Director or Directors for
cause.
 
         Section 3. Amendment, Repeal, Etc. Notwithstanding anything contained
in this Third Amended and Restated Certificate of Incorporation to the contrary,
the affirmative vote of the holders of at least 80% of the voting power of the
outstanding Voting Stock, voting together as a single class, is required to
amend or repeal, or adopt any provision inconsistent with, this Article VII.
 
                                  ARTICLE VIII
                                  ------------
 
         To the full extent permitted by the Delaware General Corporation Law or
any other applicable law currently or hereafter in effect, no Director will be
personally liable to the Company or its stockholders for or with respect to any
acts or omissions in the performance of his or her duties as a Director. If the
Delaware General Corporation Law is amended hereafter to authorize the further
elimination or limitation of the liability of directors, then the liability of a
Director shall be eliminated or limited to the fullest extent authorized by the
Delaware General Corporation Law, as so amended. Any repeal or modification of
this Article VIII will not adversely affect any right or protection of a
Director existing prior to such repeal or modification.
 
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                                   ARTICLE IX
                                   ----------
 
         Section 1. Right to Indemnification. 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 (a "Proceeding"), by reason of the fact that such person is or was
a director or an officer of the Company or is or was serving at the request of
the Company as a director, officer, employee or agent of another company or of a
partnership, joint venture, trust or other enterprise, including service with
respect to an employee benefit plan (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 Company to the
fullest extent permitted or required 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 Company to provide
broader indemnification rights than such law permitted the Company 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 3
of this Article IX with respect to Proceedings to enforce rights to
indemnification, the Company 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
Company.
 
         Section 2. Right to Advancement of Expenses. The right to
indemnification conferred in Section 1 of this Article IX shall include the
right to be paid by the Company the expenses (including, without limitation,
attorneys' fees and expenses) incurred in defending any such Proceeding in
advance of its final disposition (an "Advancement of Expenses"); provided,
however, that, if the Delaware General Corporation Law so 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 Company of an
undertaking (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 (a "Final Adjudication")
that such Indemnitee is not entitled to be indemnified for such expenses under
this Section 2 or otherwise. The rights to indemnification and to the
Advancement of Expenses conferred in Sections 1 and 2 of this Article IX shall
be contract rights and such rights shall continue as 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.
 
         Section 3. Right of Indemnitee to Bring Suit. If a claim under Section
1 or 2 of this Article IX is not paid in full by the Company within 60 calendar
days after a written claim has been received by the Company, except in the case
of a claim for an Advancement of Expenses, in which case the applicable period
shall be 20 calendar days, the Indemnitee may at any time thereafter bring suit
against the Company 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 Company to
recover an Advancement of Expenses pursuant to the terms of an Undertaking, the
Indemnitee shall be
 
 
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entitled to be paid also 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) any suit brought
by the Company to recover an Advancement of Expenses pursuant to the terms of an
Undertaking, the Company 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 Company (including its Board of Directors, independent legal
counsel or 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 Company (including its Board of Directors, independent legal counsel or
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 brought by the Company 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 IX or otherwise shall be on the Company.
 
         Section 4. Non-Exclusivity of Rights. The rights to indemnification and
to the Advancement of Expenses conferred in this Article IX shall not be
exclusive of any other right which any person may have or hereafter acquire
under any statute, the Company's Third Amended and Restated Certificate of
Incorporation, Bylaws, agreement, vote of stockholders or disinterested
directors or otherwise. The Bylaws of the Company may contain such other
provisions concerning indemnification, including provisions specifying
reasonable procedures relating to and conditions to the receipt by indemnitees
of indemnification, provided that such provisions are not inconsistent with the
provisions of this Article IX.
 
         Section 5. Insurance. The Company may maintain insurance, at its
expense, to protect itself and any director, officer, employee or agent of the
Company or another corporation, partnership, joint venture, trust or other
enterprise against any expense, liability or loss, whether or not the Company
would have the power to indemnify such person against such expense, liability or
loss under the Delaware General Corporation Law.
 
         Section 6. Indemnification of Employees and Agents of the Company. The
Company 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 Company to the fullest extent of the provisions of
this Article IX with respect to the indemnification and Advancement of Expenses
of directors and officers of the Company.
 
                                    ARTICLE X
                                    ---------
 
         Whenever a compromise or arrangement is proposed between this Company
and its creditors or any class of them and/or between this Company and its
stockholders or any class of them, any court of equitable jurisdiction within
the State of Delaware may, on the application in a summary way of this Company
or of any creditor or stockholder thereof or on the application of any receiver
or receivers appointed for this Company under Section 291 of Title 8 of the
Delaware Code or on the
 
 
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application of trustees in dissolution or of any receiver or receivers appointed
for this Company under Section 279 of Title 8 of the Delaware Code order a
meeting of the creditors or class of creditors, and/or of the stockholders or
class of stockholders of this Company as the case may be, to be summoned in such
manner as the said court directs. If a majority in number representing three
fourths in value of the creditors or class of creditors, and/or of the
stockholders or class of stockholders of this Company, as the case may be, agree
to any compromise or arrangement and to any reorganization of this Company as
consequence of such compromise or arrangement, the said compromise or
arrangement and the said reorganization shall, if sanctioned by the court to
which the said application has been made, be binding on all the creditors or
class of creditors, and/or on all the stockholders or class of stockholders, of
this Company, as the case may be, and also on this Company.
 
                                   ARTICLE XI
                                   ----------
 
         The Company is to have perpetual existence.
 
                                   ARTICLE XII
                                   -----------
 
         The Company reserves the right to amend, alter, change or repeal any
provision contained in this Third Amended and Restated Certificate of
Incorporation in the manner now or hereafter prescribed herein and by the laws
of the State of Delaware, and all rights conferred upon stockholders herein are
granted subject to this reservation.
 
 
         IN WITNESS WHEREOF, the Company has caused this Third Amended and
Restated Certificate of Incorporation to be signed by its Chief Executive
Officer on this 26th day of November, 2003.
 
 
 
 
 
                                          By:      /s/ Rodney Mott
                                                   -----------------------------
                                          Name:    Rodney Mott
                                          Title:   President and Chief Executive
                                                   Officer