AK Steel Holding (AKS)

ARTICLE II—DEFINITIONS

2.1 “Administrator” means the Compensation Committee of the Board of Directors, or such other committee or person designated by the Board of Directors.

2.2 “Beneficiary” means the person, entity or entities designated by the Participant to receive the balance of the Participant’s Supplemental Thrift Account in the event of the Participant’s death. In the absence of an express designation under this Plan, a Participant’s Beneficiary shall be his estate.

2.3 “Board of Directors” means the Board of Directors of the Company.

2.4 “Change in Control” has the same meaning under this Plan as under the Trust Agreement for the AK Steel Corporation Non-Qualified Supplemental Retirement Plans.

2.5 “Code” means the Internal Revenue Code of 1986, as amended.

2.6 “Code Section 401(a)(17) Limitation” means, with respect to a Plan Year, the applicable compensation limitation set forth in section 401(a)(17) of the Code (as adjusted as provided therein), or any corresponding successor provision.

2.7 “Code Section 415 Limitation” means, with respect to a Plan Year, the applicable limitation on annual additions to the Thrift Plan as set forth in section 415 of the Code (as adjusted as provided therein), or any corresponding successor provision.

2.8 “Company” means AK Steel Corporation and any successor to all or substantially all of the assets of the business of AK Steel Corporation.

2.9 “Company Matching Contributions” means any Company contribution made in accordance with Section 5.1 of the Plan.

2.10 “Eligible Employee” means any member of management of the Company who is selected by the Administrator to be eligible for benefits under this Plan.

2.11 “ERISA” means the Employee Retirement Income Security Act of 1974, as amended.

2.12 “Fixed Income Fund” has the same meaning under this Plan as under the Thrift Plan.

2.13 “Participant” means an Eligible Employee who has a Supplemental Thrift Account under the Plan, or a person who was such at the time of his death or termination of service and who retains, or whose Beneficiary retains, a benefit under the Plan which has not been distributed.

2.14 “Plan” means the AK Steel Corporation Supplemental Thrift Plan, as set forth herein and as it may be amended from time to time.

2.15 “Plan Year” means the calendar year.

2.16 “Supplemental Thrift Account” means the account (including any sub-accounts) established and maintained on the books of the Company for a Participant under the Plan for purposes of reflecting any Company Matching Contribution under Article V, as adjusted from time to time for investment gains or losses and distributions.

2.17 “Thrift Plan” means the AK Steel Corporation Thrift Plan, Plan Document A, as amended, and any successor or replacement plan for such plan.

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2.18 “Trust” means the trust established pursuant to the Trust Agreement for the AK Steel Corporation Non-Qualified Supplemental Retirement Plans dated February 21, 1997, as amended, and any successor or replacement trust for such trust.