FIRST AMENDMENT TO COMMERCIALLEASE

Exhibit 10.21

Execution Version

FIRST AMENDMENT TO COMMERCIAL LEASE

This FIRST AMENDMENT TO COMMERCIAL LEASE (this “Amendment”), dated as of December 14, 2012, is made and entered into by and between SDC BLACKHOLE LP (“Landlord”), and ADVANCED RIG SERVICES LLC (“ARS”) and INTEGRATED DRILLING EQUIPMENT CO. (“IDEC” and together ARS, “Tenant”).

RECITALS

A. All terms, covenants and conditions contained in this Amendment shall have the same meaning as in the Lease, and shall govern should a conflict exist with previous terms and conditions.

B. Landlord and Tenant entered into that certain Commercial Lease (the “Lease”) under and pursuant to which Tenant has leased from Landlord the “leased premises” (as described in the Lease) (the “Premises”).

C. Landlord and Tenant desire to amend certain terms, provisions and obligations set forth in the Lease.

AGREEMENT

NOW, THEREFORE, in consideration of the foregoing recitals and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, Landlord and Tenant hereby agree as follows:

1. Term. Section 3(A) of the Lease is deleted in its entirety and replaced with the following:

June 1, 2011 (Commencement Date) and ending on December 31, 2017 (Expiration Date).

2. From and after the date of this Amendment, Base Monthly Rent for the period (i) commencing on November 1, 2012 and ending on December 31, 2013 shall equal $45,000.00 (the “2012-2013 Monthly Rent”) (and Landlord acknowledges receipt of such payment in full from Tenant for the period commencing on November 1, 2012 and ending on November 30, 2012), (ii) commencing on January 1, 2014 and ending on December 31, 2014 shall equal the 2012-2013 Monthly Rent multiplied by the CPI Factor (the “2014 Monthly Rent”), (iii) commencing on January 1, 2015 and ending on December 31, 2015 shall equal the 2014 Monthly Rent multiplied by the CPI Factor (the “2015 Monthly Rent”), (iv) commencing on January 1, 2016 and ending on December 31, 2016 shall equal the 2015 Monthly Rent multiplied by the CPI Factor (the “2016 Monthly Rent”), and (v) commencing on January 1, 2017 and ending on December 31, 2017 shall equal the 2016 Monthly Rent multiplied by the CPI Factor. For purposes of this Amendment, the “CPI Factor” shall mean a fraction, the numerator of which shall be the Consumer Price Index of the Bureau of Labor Statistics of the U.S. Department of Labor (All Urban Consumers) (“CPI”) of the calendar month two months prior to the final month of the previous calendar year, and the denominator of which shall be the CPI of the first month of the previous calendar year; provided the CPI Factor shall never be less than one.

1

3. Purchase Option.

2

If Landlord and Tenant are unable to agree upon a single Appraiser within five (5) days after the end of the twenty-five day period, each will then appoint one Appraiser by written notice to the other, given within seven (7) days after the end of the twenty-five day period. Within three (3) days after the two Appraisers are appointed, the two Appraisers will appoint a third Appraiser. If either Landlord or Tenant fails to appoint its Appraiser within the prescribed time period, the single Appraiser appointed will determine the Fair Market Value. Each party will bear the cost of the Appraiser appointed by it and the parties will share equally the cost of the third Appraiser. In this case, the Fair Market Value will be the average of two of the three appraisals that are closest in amount, and the third appraisal will be disregarded.

3

4

4. Effect of This Amendment. Except as expressly amended and modified herein, all of the covenants and conditions of the Lease are and remain in full force and effect as therein written. In the event of any conflict or inconsistency between the provisions of this Amendment and the provisions of the Lease, the terms and provisions of this Amendment shall prevail and be controlling.

5

5. Multiple Counterparts. This Amendment may be executed in a number of identical counterparts, including facsimiles thereof. If so executed, each of such counterparts is to be deemed an original for all purposes, and all such counterparts shall, collectively, constitute one agreement, but, in making proof of this Amendment, it shall not be necessary to produce or account for more than one such counterpart.

6. Governing Law. This Amendment shall in all respects be governed by the laws of the State of Texas.

7. Authority. Tenant and Landlord each represents to the other party that each of the parties executing this Amendment on its behalf is authorized to do so by requisite action of its respective company.

8. Invalid Provisions. If any provision of this Amendment proves to be illegal, invalid or unenforceable, the remainder of this Amendment will not be affected by such finding, and in lieu of each provision of this Amendment that is illegal, invalid or unenforceable, a provision will be added as a part of this Amendment as similar in terms to such illegal, invalid or unenforceable provision as may be possible and be legal, valid and enforceable.

[Signatures contained on the following pages]

6

Executed this 14th day of December, 2012.

7

Exhibit A

Deed

See attached.

8

Space Above for County Recorder’s Use

NOTICE OF CONFIDENTIALITY RIGHTS: IF YOU ARE A NATURAL PERSON, YOU MAY REMOVE OR STRIKE ANY OR ALL OF THE FOLLOWING INFORMATION FROM THIS INSTRUMENT BEFORE IT IS FILED FOR RECORD IN THE PUBLIC RECORDS: YOUR SOCIAL SECURITY NUMBER OR YOUR DRIVER’S LICENSE NUMBER.

When recorded mail to:

Prepared by                                                                                  

SPECIAL WARRANTY DEED

THAT ___________________, a ________________ (“Grantor”), for and in consideration of the sum of ______________ and ___________ Dollars ($_______) cash and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, __________________, a ________________ (“Grantee”), whose address is __________________________, HAS GRANTED, BARGAINED, SOLD and CONVEYED, and by these presents DOES GRANT, BARGAIN, SELL and CONVEY unto Grantee all of that certain real property situated in _______ County, Texas, described on Exhibit A attached hereto and made a part hereof for all purposes (the “Land”), and all buildings, structures, parking areas and other improvements located thereon, together with all related rights and appurtenances, including but not limited to all right, title and interest of Grantor in and to any land lying in the bed of any street, road, highway or alley (whether opened or proposed) adjoining the Land, any water or water rights benefiting the Land, any easements benefiting the Land, and any strips and gores adjoining the Land (the Land and all of such buildings, structures, parking areas and other improvements and other rights and appurtenances being collectively referred to herein as the “Property”).

1

TO HAVE AND TO HOLD the Property unto Grantee, and Grantee’s successors and assigns forever, and Grantor does hereby bind itself and its successors and assigns to WARRANT and FOREVER DEFEND all and singular the Property unto Grantee and Grantee’s successors and assigns, against every person whomsoever lawfully claiming or to claim the same or any part thereof, by, through or under Grantor, but not otherwise, subject only to the matters listed on Exhibit B attached hereto and made a part hereof for all purposes.

[Signature on following page]

2

EXECUTED to be effective as of the 14th day of December 2012.

3

STATE OF __________         )

                                                  ) ss.

COUNTY OF ________         )

On this ____ day of _________, 20__, before me a Notary Public in and for said county and state, personally appeared ___________________ as the __________________________ of ______________________, a ___________________, known to me to be the identical person who subscribed his/her name to the foregoing and acknowledged the execution thereof to be his/her voluntary act and deed.

4

Exhibit A

Legal Description

Exhibit B

Permitted Encumbrances