Exhibit








EXHIBIT 4.2






EXECUTION VERSION


    
FIRST SUPPLEMENTAL INDENTURE


dated as of July 27, 2016


among


AK STEEL CORPORATION,


MOUNTAIN STATE CARBON, LLC,


U.S. BANK NATIONAL ASSOCIATION,
as Trustee
and
U.S. BANK NATIONAL ASSOCIATION,
as Collateral Agent


________________________


7.50%
Senior Secured Notes due 2023















THIS FIRST SUPPLEMENTAL INDENTURE (this “Supplemental Indenture”), entered into as of July 27, 2016, among AK Steel Corporation, a Delaware corporation (the “Company”), Mountain State Carbon, LLC, a Delaware limited liability company (the “Undersigned”), U.S. Bank National Association, as trustee (the “Trustee”) and U.S. Bank National Association, as collateral agent (the “Collateral Agent”).


RECITALS


WHEREAS, the Company, the Guarantors party thereto, the Trustee and the Collateral Agent entered into the Indenture, dated as of June 20, 2016 (the “Indenture”), relating to the Company’s 7.50% Senior Secured Notes due 2023 (the “Notes”);
WHEREAS, the Indenture provides that under certain circumstances a Subsidiary shall execute and deliver to the Trustee a supplemental indenture pursuant to which the Subsidiary shall unconditionally Guarantee all of the Company’s obligations under the Notes and the Indenture on the terms and conditions set forth herein; and


WHEREAS, pursuant to Section 9.01 of the Indenture, the Trustee is authorized to execute and deliver this Supplemental Indenture.


AGREEMENT
NOW, THEREFORE, in consideration of the premises and mutual covenants herein contained and intending to be legally bound, the parties to this Supplemental Indenture hereby agree as follows:
Section 1.  Capitalized terms used herein and not otherwise defined herein are used as defined in the Indenture.
Section 2.  The Undersigned, by its execution of this Supplemental Indenture, agrees to be a Guarantor under the Indenture and to be bound by the terms of the Indenture applicable to Guarantors, including, but not limited to, Article 10 thereof.
Section 3.  This Supplemental Indenture shall be governed by and construed in accordance with the laws of the State of New York without regard to principles of conflicts of law.
Section 4.  Neither the Company nor the Undersigned shall be required to make a notation on the Note to reflect the Note Guarantee or any release, termination or discharge thereof. 
Section 5.  This Supplemental Indenture may be signed in various counterparts which together will constitute one and the same instrument.
Section 6.  This Supplemental Indenture is an amendment supplemental to the Indenture, and the Indenture and this Supplemental Indenture will henceforth be read together.













IN WITNESS WHEREOF, the parties hereto have caused this Supplemental Indenture to be duly executed as of the date first above written.


	
		
	AK STEEL CORPORATION
as the Company

	By:
	/s/ Jaime Vasquez

	Name:
	Jaime Vasquez

	Title:
	Vice President, Finance and Chief  
 Financial Officer






	
		
	MOUNTAIN STATE CARBON, LLC,
as Guaranteeing Subsidiary

	By:
	/s/ Joseph C. Alter

	Name:
	Joseph C. Alter

	Title:
	Assistant Secretary






	
		
	U.S. BANK NATIONAL ASSOCIATION
as the Trustee

	By:
	/s/ William E. Sicking

	Name:
	William E. Sicking

	Title:
	Vice President and Trust Officer






	
		
	U.S. BANK NATIONAL ASSOCIATION
as the Collateral Agent

	By:
	/s/ William E. Sicking

	Name:
	William E. Sicking

	Title:
	Vice President and Trust Officer
















































[Signature Page to Supplemental Indenture]