Exhibit 3.1

AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

OF

AK STEEL HOLDING CORPORATION

FIRST. The name of the corporation is AK Steel Holding Corporation.

SECOND. The address of the Corporation’s registered office in the State of Delaware is 1209 Orange Street, City of Wilmington, County of New Castle, Delaware 19801. The name of the Corporation’s registered agent at such address is The Corporation Trust Company.

THIRD. 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.

FOURTH. The total number of shares which the corporation shall have authority to issue is 1,000 shares of common stock, par value $0.01 per share.

FIFTH. Elections of directors need not be by written ballot except and to the extent provided in the bylaws of the corporation.

SIXTH. The board of directors of the corporation is expressly authorized to adopt, amend or repeal bylaws of the corporation.

SEVENTH. A director of the corporation shall not be personally liable either to the corporation or to any stockholder for monetary damages for breach of fiduciary duty as a director, except (i) for any breach of the director’s duty of loyalty to the corporation or its stockholders, (ii) for acts or omissions which are not in good faith or which involve intentional misconduct or knowing violation of the law, (iii) for any matter in respect of which such director shall be liable under Section 174 of Title 8 of the General Corporation Law of the State of Delaware or any amendment thereto or successor provision thereto, or (iv) for any transaction from which the director shall have derived an improper personal benefit. Neither amendment nor repeal of this Article SEVENTH nor the adoption of any provision of the Certificate of Incorporation inconsistent with this Article SEVENTH shall eliminate or reduce the effect of this Article SEVENTH in respect of any matter occurring, or any cause of action, suit or claim that, but for this Article SEVENTH, would accrue or arise, prior to such amendment, repeal or adoption of an inconsistent provision.

EIGHTH. (a) The corporation shall indemnify any person who was or is a party or is threatened to be made a party to, or testifies in, any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative in nature, by reason of the fact that such person is or was, at any time prior to or during which this Article EIGHTH is in effect, a director, officer, employee or agent of the corporation, or is or was, at any time prior to or during which this Article EIGHTH is in effect, serving at the request of the corporation as a director, officer, employee or agent or in any similar capacity of any other corporation, partnership, joint venture, employee benefit plan, trust or other enterprise, against expenses (including attorneys’ fees), judgments, fines, penalties, amounts paid in settlement and other liabilities actually and reasonably incurred by such person

in connection with such action, suit or proceeding to the full extent permitted by law, and the corporation may adopt bylaws or enter into agreements with any such person for the purpose of providing for such indemnification.

(b) Expenses (including attorneys’ fees) incurred in appearing at, participating in or defending any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative, shall be paid by the corporation at reasonable intervals in advance of the final disposition of such action, suit or proceeding, upon receipt by the corporation of a written undertaking by or on behalf of the director or officer to repay such amount unless it ultimately shall be determined that such person is entitled to be indemnified by the corporation as provided herein.

(c) It is the intent of the corporation to indemnify the persons referred to in this Article EIGHTH to the fullest extent permitted by law with respect to any action, suit or proceeding arising from events that occur prior to or during the time in which this Article EIGHTH is in effect. The indemnification provided by this Article EIGHTH shall not be deemed exclusive of any other rights to which those seeking indemnification may be or become entitled under any law, bylaw, agreement, vote of stockholders or disinterested directors, or otherwise, or under any policy or policies of insurance purchased and maintained by the corporation on behalf of any such director or officer, both as to action in such person’s official capacity and as to action in another capacity while holding office, and shall continue as to a person who has ceased to be a director or officer and shall inure to the benefit of the heirs, executors and administrators of such director or officer.

(d) The indemnification provided by this Article EIGHTH shall be subject to all valid and applicable laws, and in the event this Article EIGHTH or any of the provisions hereof or the indemnification contemplated hereby are found to be inconsistent with or contrary to any such valid laws, the latter shall be deemed to control and this Article EIGHTH shall be regarded as modified accordingly, and, as so modified, shall continue in full force and effect.

NINTH. Meetings of stockholders may be held within or without the State of Delaware, as the bylaws may provide. The books of the corporation may be kept (subject to any provision contained in the General Corporation Law of the State of Delaware) outside the State of Delaware at such place or places as may be designated from time to time by the board of directors or in the bylaws of the corporation.

TENTH: The corporation reserves the right at any time and from time to time to amend, alter, change or repeal any provision contained in this Certificate of Incorporation, and other provisions authorized by the laws of the State of Delaware at the time in force may be added or inserted, in the manner now or hereafter prescribed herein or by applicable law; and all rights, preferences and privileges of whatsoever nature conferred upon stockholders, directors or any other persons whomsoever by and pursuant to this Certificate of Incorporation in its present form or as hereafter amended are granted subject to this reservation.

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