Filed by Bowne Pure Compliance





Exhibit 10.1




FIRST AMENDMENT

TO

INVESTOR RIGHTS AGREEMENT




This First Amendment to Investor Rights Agreement (this “First Amendment”) is entered
into by and among Allis-Chalmers Energy Inc., a Delaware corporation (the “Company”), and
the holders named on the signature page hereto (collectively the “Holders”).



RECITALS:




WHEREAS, the Company and Oil and Gas Rental Services, Inc., a Louisiana company, entered into
that certain Investor Rights Agreement dated as of December 18, 2006 (the “Agreement”); and




WHEREAS, the Company and the Holders desire to amend Section 2(b) of the Agreement.



NOW THEREFORE, in consideration of the premises and the respective covenants and promises
contained herein, and for other good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, the parties hereto hereby agree as follows:



1. Amendment. Section 2(b) of the Agreement is hereby deleted in its entirety and the
following substituted in its place:



Termination of Designation Rights. The Holders of a majority of the Shares shall not
be entitled to designate any nominees for election to the Board pursuant to this Agreement from and
after the date (the “Designation Rights Termination Date”) that is June 23, 2008.



2. Terms Defined in Agreement. As used in this First Amendment, except as may otherwise be
provided herein, all capitalized terms which are defined in the Agreement have the same meanings
herein as therein, all of such terms and their definitions being incorporated by reference.



3. Titles of Articles, Sections and Subsections. All titles or headings to articles,
sections, subsections or other divisions of this First Amendment are only for the convenience of
the parties and shall not be construed to have any effect or meaning with respect to the other
content of such articles, sections, subsections, or other discussion, such other content being
controlling as to the Agreement among the parties hereto.



4. Counterparts. This First Amendment may be executed in multiple counterparts. It will not
be necessary that the signatures of all parties hereto be contained on any one counterpart hereof;
each counterpart shall be deemed an original, but all of which together shall constitute one and
the same instrument.


 


 









 





5. Entire Agreement. This First Amendment embodies the final, entire agreement among the
parties hereto with respect to the subject matter hereof and thereof and supersedes any
and all prior commitments, agreements, representations and understandings whether written or
oral, relating to this First Amendment, and may not be contradicted or varied by evidence of prior,
contemporaneous or subsequent oral agreements or discussions of the parties hereto.



6. Modification. Except as expressly modified by this First Amendment, the Agreement shall
remain in full force and effect.



IN WITNESS WHEREOF, the parties have executed this Agreement to be effective as of June 23,
2008.



	 	 	 	 	 
	 	COMPANY:


ALLIS-CHALMERS ENERGY INC.

 	 
	 	/s/ Theodore F. Pound III
 	 
	 	Theodore F. Pound III 	 
	 	General Counsel & Secretary 	 
	 
	 	HOLDERS:

 	 
	 	/s/ B. A. Adams, Sr.
 	 
	 	B. A. Adams, Sr. 	 
	 	 	 
	 
	 	 	 
	 	     /s/ Burt A. Adams
 	 
	 	Burt A. Adams 	 
	 	 	 
	 
	 	 	 
	 	     /s/ Brad A. Adams
 	 
	 	Brad A. Adams 	 
	 	 	 
	 
	 	 	 
	 	     /s/ Ben A. Adams
 	 
	 	Ben A. Adams 	 
	 	 	 
	 
	 	 	 
	 	 
 	 
	 	Leah Kathryn Guarisco 	 
	 	 	 
	 
	 	 	 
	 	 
 	 
	 	Maria Cedes Guarisco 	 
	 	 	 
	 
	 	 	 
	 	 
 	 
	 	Laura Lea Guarisco 	 
	 	 	 
	 



 


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	 	     /s/ Victor Guarisco II
 	 
	 	Victor Guarisco II 	 
	 	 	 
	 
	 	 	 
	 	     /s/ Luke Victor Guarisco
 	 
	 	Luke Victor Guarisco 	 
	 	 	 
	 
	 	 	 
	 	 
 	 
	 	Victoria Ann Guarisco 	 
	 	 	 
	 
	 	 	 
	 	 
 	 
	 	Jonathan Lawrence Guarisco 	 
	 	 	 
	 




 


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