SUPPLEMENT NO. 2 TO TRUST INDENTURE

Exhibit 10.6

SUPPLEMENT NO. 2

TO

TRUST INDENTURE

THIS SUPPLEMENT NO. 2, dated August 4, 2009   (“ Supplement No. 2 ”), to that certain Trust Indenture dated May 28, 2003 (the “ Indenture ”), as supplemented by Supplement No. 1 dated May 4, 2005 (“ Supplement No. 1 ”) is by and between ROWAN COMPANIES, INC., a Delaware corporation (the “ Shipowner ”), and MANUFACTURERS AND TRADERS TRUST COMPANY, a New York banking corporation (successor-in-interest to ALLFIRST TRUST COMPANY, NATIONAL ASSOCIATION, a national banking association), as indenture trustee (the “ Indenture Trustee ” and, together with the Shipowner, the “ Parties ”).

WHEREAS , on May 28, 2003, the Shipowner executed the Indenture, and issued thereunder a Floating Rate Note designated, "United States Government Guaranteed Ship Financing Obligations, TARZAN II Series" with a maximum principal amount of $89,658,000;

WHEREAS, on May 4, 2005, in connection with the changes in Payment Dates and Stated Maturities of the Obligations the Shipowner executed Supplement No. 1 to Indenture and issued an amended and restated $89,658,000 Floating Rate Note (the "Initial Transaction");

WHEREAS, Section 4(b) of the Special Provisions of the Indenture provides that the Shipowner may redeem or repay the amended and restated Floating Rate Note, in whole or in part, on a Redemption Date designated by the Shipowner, from the proceeds of the issuance of a fixed rate note;

WHEREAS , the outstanding principal amount of the amended and restated Floating Rate Note is currently $65,746,000; and

WHEREAS , the Parties wish to amend certain documents relating to the Initial Transaction in order to provide for the complete redemption of the amended and restated Floating Rate Note by the issuance of a fixed rate note in the aggregate principal amount of $65,746,000.

NOW THEREFORE, in consideration of the mutual rights and obligations set forth herein and of other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Parties agree as follows:

Section 1.01.  Schedule A .  Schedule A to the Indenture is hereby amended by adding or substituting the following definitions:

“ Authorized Newspapers ” means The Wall Street Journal , or if it ceases to exist, then in such other newspaper(s) as the Secretary may designate.

" Effective Date " means August 4, 2009.

" Fixed Rate Note ” or “Fixed Rate Obligation” shall mean an Obligation substantially in the form of Exhibit A to Supplement No. 2 to Indenture, appropriately completed.

" Indenture Trustee " means MANUFACTURERS AND TRADERS TRUST COMPANY, a New York banking corporation (successor-in-interest to ALLFIRST TRUST COMPANY, NATIONAL ASSOCIATION, a national banking association), and any successor trustee permitted under the Indenture.

“ Letter of Representations ” means the Blanket Issuer Letter of Representations between the Shipowner and DTC, any Riders thereto, and DTC’s Operational Arrangements, and other documentation necessary or desirable to effectuate the issuance of the Fixed Rate Notes as Global Obligations.

“ Mortgage ” means the first preferred continuing mortgage on the Vessel, Contract No. MA-13845, granted under the laws of the Republic of the Marshall Islands by the Shipowner to the Secretary, as originally executed, modified, amended or supplemented.

“ Reinvestment Rate ” means the yield determined by the Indenture Trustee, based on information received from the Holder or calculation agent, to be the yield of the issue of actively traded United States Treasury securities having a maturity equal to the Weighted Average Life to Final Maturity plus 0.25%; provided, however, that if such Weighted Average Life to Final Maturity is not equal to the maturity of an actively traded United States Treasury security (rounded to the nearest one-twelfth of a year), such yield shall be obtained by linear interpolation from the yields of actively traded United States Treasury securities having the greater maturity closest to and the lesser maturity closest to such Weighted Average Life to Final Maturity.  The yields shall be determined by reference to the yields as indicated by Telerate Access Service (page 8003 or the relevant page at the date of determination indicating such yields) (or, if such data ceases to be available, any publicly available sources of similar market data) at approximately 11:00 a.m. (New York City time) on the Make-Whole Premium Determination Date.

“ Secretary ” or “ Administrator ” means the Secretary of Transportation or any official or official body from time to time duly authorized to perform the duties and functions of the Secretary of Transportation under Title XI of the Act (including the Maritime Administrator, the Acting Maritime Administrator, and to the extent so authorized, the Deputy Maritime Administrator, the Acting Deputy Maritime Administrator and other officials of the Maritime Administration.

“ Supplement No. 2 to Indenture ” means the Supplement No. 2 to Trust Indenture dated August 4, 2009, between the Shipowner and the Indenture Trustee.

“ Title XI ” means Title XI of the Act (now codified as Chapter 537 of Title 46 of the U.S. Code).

“ Vessel ” means the Shipowner's self-elevating mobile offshore drilling unit named the BOB KELLER (ex- TARZAN II) (O.N. 3160) and constructed by LETOURNEAU, INC. in accordance with the Construction Contract, including all work and material heretofore or hereafter performed upon or installed in or placed on board such Vessel, together with related appurtenances, additions, improvements, and replacements.

All other capitalized terms used herein have the meanings set forth in Schedule A to the Indenture, as amended.

ARTICLE SECOND

The Indenture shall be amended as follows:

Section 2.01.  The Obligations.   Article 2(a) of the Special Provisions of the Indenture is hereby amended and restated in its entirety as follows:

Section 2.02.  Article 4(a) and (c) of the Special Provisions of the Indenture is hereby amended and restated in its entirety to read as follows: