SECURITY AGREEMENT

EXHIBIT -4.15

NOTWITHSTANDING ANYTHING HEREIN TO THE CONTRARY, THE LIEN AND SECURITY INTEREST GRANTED TO THE TRUSTEE PURSUANT TO THIS AGREEMENT AND THE EXERCISE OF ANY RIGHT OR REMEDY BY THE TRUSTEE HEREUNDER ARE SUBJECT TO THE PROVISIONS OF THE INTERCREDITOR AND LIEN SUBORDINATION AGREEMENT, DATED AS OF MARCH 25, 2004 (AS AMENDED, SUPPLEMENTED OR OTHERWISE MODIFIED FROM TIME TO TIME) AMONG LASALLE BANK NATIONAL ASSOCIATION, AS TRUSTEE FOR CERTAIN SECURED PARTIES, ISPAT INLAND FINANCE, LLC, ISPAT INLAND INC., ANY CREDIT PARTIES PARTY THERETO, AND GENERAL ELECTRIC CAPITAL CORPORATION, AS AGENT FOR CERTAIN LENDERS.

SECURITY AGREEMENT

     SECURITY AGREEMENT, dated as of March 25, 2004 (this “ Security Agreement ”), between ISPAT INLAND INC., a Delaware corporation (the “ Company ” and, together with each other Person becoming party to this Security Agreement by executing a joinder agreement in the form of Exhibit B hereto, each a “ Grantor ” and collectively the “ Grantors ”), and LASALLE BANK NATIONAL ASSOCIATION as Trustee (in such capacity, the “ Trustee ”) for the Secured Parties (as defined below).

W I T N E S S E T H :

     WHEREAS, reference is made to the Indenture dated as the date hereof (as amended, supplemented or otherwise modified from time to time, the “ Indenture ”), among Ispat Inland ULC (the “ Issuer ”), Ispat International N.V., the Company, the guarantors from time to time party thereto, and the Trustee.

     WHEREAS, pursuant to the Indenture, the Issuer has issued its Senior Secured Floating Rate Notes due 2010 in the aggregate principal amount of $150,000,000 (the “ Floating Rate Notes ”) and 9 3/4% Senior Secured Notes due 2014 in the aggregate principal amount of $650,000,000 (the “ Fixed Rate Notes ” and together with the Floating Rate Notes and any Additional Notes (as defined in the Indenture) following the date hereof, the “ Notes ”). Each Grantor has agreed to guarantee, among other things, all the obligations of the Issuer under the Indenture. The obligations of the initial purchasers of the Notes being issued on the date hereof to purchase such Notes are conditioned upon, among other things, the execution and delivery by the Grantors of this Security Agreement in the form hereof to secure each Grantor’s Note Guarantee of (a) the due and punctual payment of (i) the principal of and premium, if any, and interest (including interest accruing during the pendency of any bankruptcy, insolvency, receivership or other similar proceeding, regardless of whether allowed or allowable in such proceeding) on the Notes, when and as due, whether at maturity, by acceleration, upon one or more dates set for prepayment or otherwise, and (ii) all other monetary obligations, including fees, costs, expenses and indemnities, whether primary, secondary, direct, contingent, fixed or otherwise (including monetary obligations incurred during the pendency of any bankruptcy, insolvency, receivership or other similar proceeding, regardless of whether allowed or allowable in such proceeding), of the Issuer to the Secured Parties under the Indenture and the Notes and other documents executed in connection with the Indenture (collectively, the “ Indenture Documents ”), and (b) the due and punctual performance of all covenants, agreements, obligations and liabilities of the other Parties under or pursuant to the Indenture and the other Indenture Documents (all the monetary and other obligations referred to in the preceding clauses (a) and (b) being referred to collectively as the “ Obligations ”). “ Secured Parties ” as used herein shall mean the holders from time to time of the Notes, the Trustee, and the successors and assigns of each of the foregoing.

     WHEREAS, in order to induce Trustee to enter into the Indenture Documents and to induce the initial purchaser of the Notes being issued on the date hereof to purchase such Notes, each Grantor has agreed to grant a continuing Lien on the Collateral (as hereinafter defined) to secure the Obligations;

     WHEREAS, the Grantors have previously granted the lenders under the GECC Credit Agreement (as defined in the Indenture) (together with any successor facility secured a Permitted Inventory Collateral Lien, the “ Working Capital Credit Agreement ”) a security interest in the Collateral;

     NOW, THEREFORE, the Grantors and the Trustee, on behalf of itself and each Secured Party (and each of their respective successors or assigns), hereby agree as follows:

1. DEFINED TERMS .

     (a) All other terms contained in this Security Agreement, unless the context indicates otherwise, have the meanings provided for by the Code to the extent the same are used or defined therein.

     (b) “Uniform Commercial Code jurisdiction” means any jurisdiction that has adopted all or substantially all of Article 9 as contained in the 2000 Official Text of the Uniform Commercial Code, as recommended by the National Conference of Commissioners on Uniform State Laws and the American Law Institute, together with any subsequent amendments or modifications to the Official Text.

     (c) The following shall have (unless otherwise provided elsewhere in this Agreement) the following respective meanings (such meanings being equally applicable to both the singular and plural form of the terms defined):

     “ Code ” means the Uniform Commercial Code as the same may, from time to time, be enacted and in effect in the State of New York; provided , that in the event that, by reason of mandatory provisions of law, any or all of the attachment, perfection or priority of, or remedies with respect to, Trustee’s Lien on any Collateral is governed by the Uniform Commercial Code as enacted and in effect in a jurisdiction other than the State of New York, the term “ Code ” shall mean the Uniform Commercial Code as enacted and in effect in such other jurisdiction solely for purposes of the provisions thereof relating to such attachment, perfection, priority or remedies and for purposes of definitions related to such provisions.

     “ Excluded Subsidiary ” means Ispat Inland Mining Company, a Delaware corporation.

     “ Lien ” has the meaning given such term in the Indenture.

     “ Note Default ” shall mean a Default, as such term is defined in the Indenture.

     “ Note Event of Default ” shall mean an Event of Default, as such term is defined in the Indenture.

     “ Note Termination Date ” means the first date following the date of this Security Agreement (i) when all the Obligations have been indefeasibly paid in full, (ii) the Indenture has been discharged pursuant to Section 9.01 of the Indenture or (iii) a legal defeasance has occurred pursuant to Section 9.02 of the Indenture or a covenant defeasance has occurred pursuant to Section 9.03 of the Indenture.

     “ Permitted Inventory Collateral Liens ” has the meaning given such term in the Indenture.

     “ Permitted Liens ” has the meaning given such term in the Indenture.

     “ Receivables and Related Assets ” has the meaning given such term in the Indenture.

     “ Receivables Securitization Facility ” means the Receivables Securitization Facility (as defined in the Working Capital Credit Agreement) and any other receivables securitization facility of any Securitization Subsidiary (as defined in the Indenture).

     “ Subsidiary ” has the meaning given such term in the Inventory.

     “ Working Capital Agent ” means, (i) with respect to the Working Capital Credit Facility in effect on the date hereof, General Electric Capital Corporation, as agent for the lenders thereunder and (ii) with respect to any other Working Capital Credit Facility, the agent for the lenders under such Working Capital Credit Facility.

     “ Working Capital Loan Documents ” shall mean Loan Documents, as such term is defined in the Working Capital Credit Agreement.

     “ Working Capital Security Agreement ” shall mean the “Security Agreement”, as such term is defined in the Working Capital Credit Agreement.

     2.  GRANT OF LIEN . To secure the prompt and complete payment, performance and observance of all of the Obligations, each Grantor hereby grants to Trustee, for itself and the benefit of each of the other Secured Parties, a security interest in all of such Grantor’s right, title and interest in, to and under the following personal property and other assets, whether now owned by or owing to, or hereafter acquired by or arising in favor of, such Grantor (including under any trade names, styles or derivations thereof), and whether owned or consigned by or to, or leased from or to, such Grantor, and regardless of where located (all of which being hereinafter collectively referred to as the “ Collateral ”):

     (i) all Inventory;

     (ii) all Documents, books and records relating to the Inventory;

     (iii) all tort claims, insurance claims and other claims, causes of action or rights to payments relating to the Inventory; and

     (iv) all products of any of the foregoing and all substitutions, replacements, accessions, products and Proceeds (including insurance proceeds) of any of the foregoing;

provided that, notwithstanding the foregoing, the Collateral shall not extend to any Receivables and Related Assets other than any right to payment in respect of Inventory which is not an Account.

     3.  TRUSTEE’S AND SECURED PARTIES’ RIGHTS; LIMITATIONS ON TRUSTEE’S AND SECURED PARTIES’ OBLIGATIONS . It is expressly agreed by each Grantor that, anything herein to the contrary notwithstanding, each Grantor shall remain liable under each of its contracts and each of its licenses, in each case to the extent relating to the Collateral, to observe and perform all the conditions and obligations to be observed and performed by it thereunder. Neither Trustee nor any other Secured Party shall have any obligation or liability under any such contract or license by reason of or arising out of this Security Agreement or the granting herein of a Lien on the Collateral or the receipt by Trustee or any other Secured Party of any payment relating to any such contract or license pursuant hereto. Neither Trustee nor any other Secured Party shall be required or obligated in any manner to perform or fulfill any of the obligations of any Grantor under or pursuant to any such contract or license, or to make any payment, or to make any inquiry as to the nature or the sufficiency of any payment

received by it or the sufficiency of any performance by any party under any such contract or license, or to present or file any claims, or to take any action to collect or enforce any performance or the payment of any amounts which may have been assigned to it or to which it may be entitled at any time or times.

4. REPRESENTATIONS AND WARRANTIES . Each Grantor represents and warrants that:

     (a) Such Grantor has rights in and the power to transfer each item of the Collateral upon which it purports to grant a Lien hereunder free and clear of any and all Liens other than Permitted Inventory Collateral Liens.

     (b) No effective security agreement, financing statement, equivalent security or Lien instrument or continuation statement covering all or any part of the Collateral is on file or of record in any public office, except such as may have been filed (i) by such Grantor in favor of Trustee pursuant to this Security Agreement or the other Indenture Documents or (ii) as otherwise permitted by clause (a).

     (c) This Security Agreement is effective to create a valid and continuing Lien on and, upon the timely filing of the appropriate financing statements in the filing offices listed on Schedule III hereto (or, with respect to any Grantor that becomes a party hereto through the execution of a joinder agreement, on such joinder agreement), a perfected Lien in favor of Trustee, for itself and the benefit of the other Secured Parties, in the jurisdictions of such filings and to the extent of such filings, on the Collateral with respect to which a Lien may be perfected by filing pursuant to the Code; provided , that the Lien of the Trustee on any Collateral that is not located in the United States or the Province of Ontario, Canada need not be perfected by the filing of a financing statement or otherwise. All such perfected Liens are prior to all other Liens, except Permitted Inventory Collateral Liens, and (except as enforceability may be limited by: (i) applicable bankruptcy, insolvency, fraudulent conveyance, reorganization, moratorium or similar laws affecting the rights of creditors generally or (ii) general principles of equity (regardless of whether considered in a proceeding in equity or at law)) is enforceable as such as against any and all creditors of and purchasers from each Grantor (other than purchasers and lessees thereof). As of the date of this Security Agreement, all action by each Grantor necessary to protect and perfect such Lien on each item of the Collateral in which perfection may be effected by filing of a financing statement has been duly taken except to the extent otherwise permitted pursuant to the terms hereof or of the other Working Capital Loan Documents. Notwithstanding anything herein to the contrary, the parties hereto hereby acknowledge and agree that the perfection of Trustee’s security interest in the Collateral shall be subject to the steps required to perfect the Working Capital Agent’s first priority perfection therein.

     (d) Each Grantor’s name as it appears in official filings in the state of its in- corporation or other organization, the type of entity of such Grantor (including corporation, general or limited partnership or limited liability company), organizational identification number issued by such Grantor’s state of incorporation or organization (or a statement that no such number has been issued), such Grantor’s state of organization or incorporation, the location of such Grantor’s chief executive office, principal place of business, offices, all warehouses and premises where Collateral is located, and the locations of its material books and records concerning the Collateral are set forth on Schedule I hereto. Each Grantor has only one state of incorporation or organization. Upon written request from the Trustee, Schedule I shall be updated from time to time to reflect changes in locations of all warehouses and premises where Collateral is located.

     5.  COVENANTS . Each Grantor covenants and agrees with Trustee, for the benefit of Trustee and the other Secured Parties, that from and after the date of this Security Agreement and until the Note Maturity Date:

     (a) Further Assurances: Pledge of Instruments: Chattel Paper .

     (i) At any time and from time to time, upon the written request of Trustee and at the sole expense of such Grantor, such Grantor shall promptly and duly execute and deliver any and all such further documentation and take such further actions as Trustee may deem desirable to obtain the full benefits of this Security Agreement and of the rights and powers herein granted, including (A) using its best efforts to secure all consents and approvals necessary to enforce the security interests granted by it hereunder; and (B) if requested by Trustee, filing any financing or continuation statements under the Code with respect to the Liens granted hereunder as to those jurisdictions that are not Uniform Commercial Code jurisdictions.

     (ii) Subject to the rights of the Working Capital Agent under the Working Capital Security Agreement, such Grantor shall deliver to Trustee all Collateral consisting of negotiable Documents, Chattel Paper and Instruments (in each case, accompanied by, allonges or other instruments of transfer executed in blank) promptly after such Grantor receives the same.

     (iii) Subject to the rights of the Working Capital Agent under the Working Capital Security Agreement, such Grantor shall take all steps necessary to grant the Trustee control of all electronic chattel paper constituting Collateral owned by it in accordance with the Code and all “transferable records” (as defined in each of the Uniform Electronic Transactions Act and the Electronic Signatures in Global and National Commerce Act) constituting Collateral owned by it.

     (iv) Such Grantor hereby agrees to file, and agrees that the Trustee may file, if instructed by the holders of Notes in accordance with the Indenture, any initial financing statements and amendments thereto that (A) indicate the Collateral (regardless of whether any particular assets comprised in the Collateral falls within the scope of Article 9 of the Code of such jurisdiction) as being of an equal or lesser scope or with greater detail, and (B) contain any other information required by part 5 of Article 9 of the Code for the sufficiency or filing office acceptance of any financing statement or amendment, including whether such Grantor is an organization, the type of organization and any organization identification number issued to such Grantor. Such Grantor agrees to furnish evidence of such filings to the Trustee promptly upon request.

     (v) Such Grantor shall promptly, and in any event within ten (10) Business Days after the same is acquired by it, notify Trustee of any Commercial Tort Claim acquired by it if such Commercial Tort Claim (i) constitutes Collateral and (ii) is in excess of $1,000,000. Unless otherwise consented by Trustee, such Grantor shall enter into a supplement to this Security Agreement, granting to Trustee a Lien in such commercial tort claim.

     (b) Maintenance of Records . Such Grantor shall keep and maintain, at its own cost and expense, complete records of the Collateral, including a record of any and all payments received and any and all credits granted with respect to the Collateral and all other dealings with the Collateral. Each Grantor shall mark its books and records pertaining to the Collateral to evidence this Security Agreement and the Liens granted hereby. If any Grantor retains possession of any Collateral consisting of Chattel Paper or Instruments with Trustee’s consent, such Chattel Paper and Instruments shall be marked by such Grantor with the following legend: “This writing and the obligations evidenced or secured hereby are subject to the security interest

of LaSalle Bank National Association, as Trustee, for the benefit of Trustee and certain other Secured Parties”; provided that prior to the Termination Date, the word “This” in such legend shall be deleted and replaced with the following: “Subject to the prior security interest of the Working Capital Agent, this”.

     (c) Covenant . Other than in connection with transfers of Inventory and Related Assets to a Securitization Subsidiary, the Company will not take any action or series of actions for the primary purpose of causing a substantial portion of the Inventory used in the businesses of the Company and its Subsidiaries to be owned by a Subsidiary of the Company that has not granted a Lien in its Inventory to the Trustee for the benefit of the Secured Parties, subject to Permitted Inventory Collateral Liens (it being agreed, that no violation of this covenant shall be deemed to have occurred as a result of the Excluded Subsidiary’s ownership of Inventory in the ordinary course of its business).

     (d) Compliance with Terms, etc . Except where the failure to do so is not deemed material, individually or in the aggregate, each Grantor will perform and comply with all its obligations in respect of the Collateral and all other agreements to which it is a party or by which it is bound relating to the Collateral.

     (e) Limitation on Liens on Collateral . Such Grantor will not create, permit or suffer to exist, and Grantors will defend the Collateral against, and take such other action as is necessary to remove, any Lien on the Collateral except Permitted Inventory Collateral Liens, and will defend the right, title and interest of Trustee and the other Secured Parties in and to any of such Grantors’ rights under the Collateral against the claims and demands of all persons whomsoever.

     (f) Limitations on Disposition . Such Grantors will not sell, license, lease, transfer or otherwise dispose of any of its Collateral, or attempt or contract to do so except as permitted by the Indenture.

     (g) Further Identification of Collateral; Collateral Reports . (i) Such Grantor will, if so requested by Trustee, furnish to Trustee, as often as Trustee requests, after reasonable advance notice, statements and schedules further identifying and describing its Collateral and such other reports in connection with its Collateral as Trustee may reasonably request, all in such detail as Trustee may reasonably specify.

     (ii) Such Grantor will, upon the occurrence and continuation of an Event of Default under the Working Capital Credit Agreement or a Note Event of Default under the Indenture, promptly furnish Trustee such reports (including Collateral Reports) in connection with the Collateral as Trustee may reasonably request.

     (h) Notices . Such Grantor will advise Trustee promptly, in reasonable detail, of any Lien or claim made or asserted against any of the Collateral, to the extent such Lien is not permitted pursuant to clause (e).

     (i) No Reincorporation . No Grantor shall reincorporate or reorganize itself under the laws of any jurisdiction other than the jurisdiction in which it is incorporated or organized as of the date hereof unless such Grantor has taken such steps as may be required to preserve the validity and priority of the Trustee’s Lien on the Collateral.

     (j) Termination; Amendments Not Authorized . Such Grantor acknowledges that it is not authorized to file any amendment or termination statement with respect to any financing

statement with respect to its Collateral filed for the benefit of the Trustee without the prior written consent of Trustee and agrees that it will not do so without the prior written consent of Trustee, subject to such Grantor’s rights under Section 9-509(d)(2) of the Code and subject to the requirements of the TIA (as defined in the Indenture).

     (k) Authorized Terminations . On the Note Termination Date, Trustee shall take the actions required by Section 15(b) hereof.

     6.  TRUSTEE’S APPOINTMENT AS ATTORNEY-IN-FACT . Concurrently with the execution of this Security Agreement (or, with respect to any Grantor that becomes a party hereto through the execution of a joinder agreement, on the date of such joinder agreement) each Grantor shall execute and deliver to Trustee a power of attorney (the “ Power of Attorney ”) substantially in the form attached hereto as Exhibit A. The power of attorney granted pursuant to the Power of Attorney is a power coupled with an interest and shall be irrevocable until the Note Termination Date. The powers conferred on Trustee, for the benefit of Trustee and the other Secured Parties, under the Power of Attorney are solely to protect Trustee’s interests (for the benefit of Trustee and the other Secured Parties) in the Collateral and shall not impose any duty upon Trustee or any other Secured Party to exercise any such powers. Trustee agrees that it shall not exercise any power or authority granted under the Power of Attorney unless a Note Event of Default has occurred and is continuing and the Termination Date has occurred, and (b) Trustee shall account for any moneys received by Trustee in respect of any foreclosure on or disposition of Collateral pursuant to the Power of Attorney; provided that none of Trustee or any other Secured Party shall have any duty as to any Collateral, and Trustee and the other Secured Parties shall be accountable only for amounts that they actually receive as a result of the exercise of such powers. NONE OF TRUSTEE, THE OTHER SECURED PARTIES OR THEIR RESPECTIVE AFFILIATES, OFFICERS, DIRECTORS, EMPLOYEES, AGENTS OR REPRESENTATIVES SHALL BE RESPONSIBLE TO GRANTORS FOR ANY ACT OR FAILURE TO ACT UNDER ANY POWER OF ATTORNEY OR OTHERWISE, EXCEPT IN RESPECT OF DAMAGES ATTRIBUTABLE SOLELY TO THEIR GROSS NEGLIGENCE OR WILLFUL MISCONDUCT AS FINALLY DETERMINED BY A COURT OF COMPETENT JURISDICTION, NOR FOR ANY PUNITIVE, EXEMPLARY, INDIRECT OR CONSEQUENTIAL DAMAGES.

     7.  REMEDIES; RIGHTS UPON DEFAULT .

     (a) Subject to the rights of the Working Capital Agent under the Working Capital Loan Documents and the Intercreditor Agreement referred to in Section 25 , in addition to all other rights and remedies granted to it under this Security Agreement, the Indenture, the other Indenture Documents and under any other instrument or agreement securing, evidencing or relating to any of the Obligations, if any Note Event of Default shall have occurred and be continuing, Trustee may exercise all rights and remedies of a secured party under the Code. Without limiting the generality of the foregoing, each Grantor expressly agrees that in any such event Trustee, without demand of performance or other demand, advertisement or notice of any kind (except the notice specified below of time and place of public or private sale) to or upon such Grantor or any other Person (all and each of which demands, advertisements and notices are hereby expressly waived to the maximum extent permitted by the Code and other applicable law), may forthw