SecProbe.io

May 2, 2011
 Via E-Mail

Clay C. Williams Executive Vice President and  Chief Financial Officer National Oilwell Varco, Inc. 7909 Park Circle Drive Houston, Texas 77036-6565
Re: National Oilwell Varco, Inc.
Form 10-K for Fiscal Year Ended December 31, 2010 Filed February 23, 2011
  File No. 001-12317

Dear Mr. Williams:
 We have reviewed your filing and have the following comments.  We have limited our
review to only your financial statements and re lated disclosures and do not intend to expand our
review to other portions of your documents.  In  some of our comments, we may ask you to
provide us with information so we may better understand your disclosure.
 Please respond to this letter within te n business days, by providing the requested
information, or by advising us when you will provide the requested response.  If you do not believe our comments apply to your facts and circum stances, please tell us w hy in your response.

After reviewing the information you provide in response to these comments, we may
have additional comments.    Form 10-K for Fiscal Year Ended December 31, 2010

 General

 1. We note from publicly available company pr ofiles and analyst re ports that you have
conducted business in and exported to Iran.  We also note publicly av ailable profiles for
managers for your company in the Syria, Tu rkey and Jordan region.  We note from an
October 2010 news article that your company may have supplied a blowout preventer to a
rig in Cuba.  Finally, we not e from pages 16 and 20 of your Form 10-K that you have
operations in Africa.    Sudan, located in Africa, and Iran, Syria and Cuba are identified by the State Department
as state sponsors of terrorism and are s ubject to U.S. economic sanctions and export
controls.  We note that your Form 10-K does not include disclosure about business

Clay C. Williams
National Oilwell Varco, Inc. May 2, 2011 Page 2

 contacts with these countries.  Please descri be to us the nature a nd extent of your past,
current, and anticipated cont acts with Iran, Syria, Suda n and Cuba, whether through
subsidiaries or other direct or  indirect arrangements.  Your  response should also describe
any services or products you have provided to Iran, Syria, Sudan or Cuba and any
agreements, commercial arrangements, or  other contacts you have had with the
governments of Iran, Syria, Sudan or Cuba, or entities controlled by these governments.

2. Please discuss the materiality of your contacts  with Iran, Syria, Sudan or Cuba described
in response to our foregoing comment and whet her those contacts constitute a material
investment risk for your security holders.  You should address mate riality in quantitative
terms, including the approximate dollar amount s of any associated revenues, assets, and
liabilities for the last  three fiscal years and subseque nt interim period.  Also, address
materiality in terms of qualitative factor s that a reasonable in vestor would deem
important in making an investment decision, including the potential impact of corporate
activities upon a company’s reputation and sh are value.  Various state and municipal
governments, universities, and other investor s have proposed or a dopted divestment or
similar initiatives regarding investment in companies that do business with U.S.-
designated state sponsors of terrorism.  Your  materiality analysis  should address the
potential impact of the investor sentiment evidenced by such actions directed toward
companies that have operations associated w ith Iran, Syria, Sudan and Cuba, and should
discuss the possibility for re putational harm from your join t venture with Schlumberger
and your relationship Samsung Hea vy Industries.  In this rega rd, we note that your joint
venture partner Schlumberger states on its website that it has operations in Iran, Syria,
Sudan and Cuba.  We note also that y our significant customer Samsung Heavy
Industries’ parent has an office in and conducts business in Iran.

3. We note the disclosure on page 20 regardi ng government inquiries related to compliance
with export trade laws and regulations and your  subsequent internal review.  Please tell
us the nature of the actions underlying the inquiries and the countries involved.
 Management’s Discussion and Analysis of Fi nancial Condition and Results of Operations

 Executive Summary, page 36

 4. We note you have presented cert ain non-GAAP measures in y our filing such as diluted
earnings per share excluding intangible asset impairment and transaction, devaluation and
voluntary retirement charges and operating profit excluding trans action charges.
However, it does not appear that the presenta tion of these non-GAAP measures is
accompanied by a clearly understandable reconcili ation to the most directly comparable
GAAP measures.  Please confirm that you will provide this type of reconciliation in
connection with the future presentation of any non-GAAP measures.  Refer to Item
10(e)(1)(i) of Regulation S-K.

Clay C. Williams
National Oilwell Varco, Inc. May 2, 2011 Page 3

 Financial Statements

 Notes to Consolidated Financial Statements

 Note 10 – Employee Benefit Plans, page 81

 5. It does not appear that you ha ve provided all of the require d disclosures regarding your
defined-contribution benefit plans.  For ex ample, it does not app ear that you have
provided the required disclosures regardi ng amounts recorded in accumulated other
comprehensive income related to these plans.   It also does not appear that you have
provided disclosure regarding the assumed health care cost trend rate used to measure
your benefit costs.  Please revise to provi de the disclosures pr escribed by FASB ASC
715-20-50.
 Note 12 – Commitments and Contingencies, page 85

 6. We note your disclosure stati ng that your total liability re lated to claims, regulatory
agency audits, and pending or threatened lega l actions cannot be dete rmined at December
31, 2010.  Your disclosure also st ates that any ultimate liabili ty related to these matters,
to the extent not otherwise provided for, will not materially affect your financial position,
cash flow, or results of operations.   Pl ease describe any matters for which you have
recorded a contingent liability (i.e., the amount s that have been provided for, as indicated
in your footnote) pursuant to FASB ASC 450-20-25.  In addition, with regard to
contingencies for which you have not recogni zed a liability, please provide disclosure
regarding management’s assessment of the proba bility that a liability has been incurred
and the related possible loss or  range of loss.  Refer to FASB ASC 450-20-50-3 through
450-20-50-4.
 Form 8-K filed April 27, 2011

 7. We note you present an EBITDA measure a nd a corresponding reconciliation to net
income.  However, your reconciliation and definition of EBITDA presented includes an
additional adjustment for transaction and deva luation costs, the inclusion of which does
not conform to the specifically defined m easure, EBITDA, as described in Item
10(e)(1)(ii)(a) of Regulation S-K.  Please confirm that you will revise future public
disclosures to reflect the proper measur e for EBITDA or that you will revise your
disclosures to more accura tely depict the non-GAAP m easure you are presenting.

             We urge all persons who are res ponsible for the accuracy and adequacy of the disclosure
in the filing to be certain that the filing include s the information the Securities Exchange Act of
1934 and all applicable Exchange Act rules requir e.  Since the company and its management are
in possession of all facts relating to a company’s disclosure, they are responsible for the accuracy
and adequacy of the disclosures they have made.

Clay C. Williams
National Oilwell Varco, Inc. May 2, 2011 Page 4

             In responding to our comments, please provide a written statement from the company
acknowledging that:
• the company is responsible for the adequacy an d accuracy of the disclo sure in the filing;

• staff comments or changes to disclosure in response to staff comments do not foreclose
the Commission from taking any action with respect to the filing; and

• the company may not assert staff comments as  a defense in any proceeding initiated by
the Commission or any person under the federa l securities laws of  the United States.

You may contact Andri Boerman at (202) 551- 3645 or me at (202) 551-3311 if you have
questions regarding comments.
Sincerely,
   /s/ Ethan Horowitz   Ethan Horowitz  Accounting Branch Chief