Form 425
Filed by Bronco Drilling Company, Inc.
pursuant to Rule 425 under the Securities Act of 1933
and deemed filed pursuant to Rule 14a-12
of the Securities Exchange Act of 1934
Subject Company: Allis-Chalmers Energy, Inc.
Commission File No.: 001-02199
Bronco Drilling Company, Inc. Announces Monthly Operating Results
OKLAHOMA CITY, July 10, 2008 (BUSINESS WIRE)Bronco Drilling Company, Inc., (Nasdaq/GM:BRNC),
announced today operational results for the month ended and as of June 30, 2008.
Utilization for the Companys drilling fleet was 83% for the month of June compared to 85% for the
previous month and 69% for the first quarter of 2008. The Company had an average of 45 marketed
drilling rigs in June compared to 45 in the previous month and 45 for the first quarter of 2008.
The average dayrate on operating drilling rigs as of June 30, 2008, was $17,564 compared to $16,561
as of May 31, 2008, and $17,101 for the first quarter of 2008. The increase in average dayrate on
operating drilling rigs as of June 30, 2008, is partially due to a wage increase initiated during
June for Bronco field personnel that is contractually passed through to Broncos customers. The
wage increase resulted in a $750 increase in the average dayrate.
Utilization for the Companys workover fleet was 74% for the month of June compared to 74% for the
previous month and 77% for the first quarter of 2008. The Company had an average of 54 marketed
workover rigs in June compared to 53 in the previous month and 48 for the first quarter of 2008.
The Company cautions that several factors other than those discussed above may impact the Companys
operating results and that a particular trend regarding the factors above may or may not be
indicative of the Companys current or future financial performance.
About Bronco Drilling
Bronco Drilling Company, Inc. is a publicly held company headquartered in Edmond, Oklahoma, and is
a provider of contract land drilling and workover services to oil and natural gas exploration and
production companies. Broncos common stock is quoted on The NASDAQ Global Market under the symbol
BRNC. For more information about Bronco Drilling Company,
Inc., visit http://www.broncodrill.com.
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Important Information
On January 23, 2008, Bronco entered into a merger agreement with Allis-Chalmers Energy Inc.
(Allis-Chalmers), providing for the acquisition of Bronco by Allis-Chalmers. On June 1, 2008,
Bronco and Allis Chalmers entered into an amendment to such merger agreement. In connection with
the proposed merger, Allis-Chalmers filed a registration statement on Form S-4 (Registration No.
333-149326) with the Securities and Exchange Commission (the SEC) on February 20, 2008, a first
amendment to such registration statement on Form S-4 with the SEC on March 27, 2008, and a second
amendment to such registration statement on Form S-4 with the SEC on June 9, 2008, a third
amendment to such registration statement on Form S-4 with the SEC on June 26, 2008, and a fourth
amendment to such registration statement on Form S-4 with the SEC on July 10, 2008, which
registration statement contains a joint proxy statement/prospectus of both companies.
Allis-Chalmers and Bronco may file other relevant documents concerning the proposed merger,
including any amendments to such registration statement. INVESTORS ARE URGED TO READ THE JOINT
PROXY STATEMENT/PROSPECTUS AND ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC, BECAUSE THEY
CONTAIN IMPORTANT INFORMATION REGARDING THE MERGER. Investors and security holders may obtain a
free copy of the joint proxy statement/prospectus and the other documents free of charge at the
website maintained by the SEC at www.sec.gov.
The documents filed with the SEC by Allis-Chalmers may be obtained free of charge from
Allis-Chalmers website at www.alchenergy.com or by calling Allis-Chalmers Investor Relations
department at (713) 369-0550.
The documents filed with the SEC by Bronco may be obtained free of charge from Broncos website at
www.broncodrill.com or by calling Broncos Investor Relations department at (405) 242-4444.
Investors and security holders are urged to read the joint proxy statement/prospectus and the other
relevant materials before making any voting or investment decision with respect to the proposed
merger.
Allis-Chalmers, Bronco and their respective directors and executive officers may be deemed to be
participants in the solicitation of proxies from the respective stockholders of Allis-Chalmers and
Bronco in connection with the merger. Information regarding such persons and a description of their
interests in the merger are contained in the joint proxy statement/prospectus filed with the SEC,
as it may be amended or supplemented from time to time. Information about the directors and
executive officers of Allis-Chalmers and their ownership of Allis-Chalmers common stock is set
forth in its amended annual report on Form 10-K/A filed with the SEC on July 10, 2008, as further
amended, and in subsequent statements of changes in beneficial ownership on file with the SEC.
Information about the directors and executive officers of Bronco and their ownership of Broncos
common stock is set forth in its amended annual report on Form 10-K/A filed with the SEC on April
29, 2008 and in subsequent statements of changes in beneficial ownership on file with the SEC.
Investors may obtain additional information regarding the interests of such participants by reading
the joint proxy statement/prospectus for the merger, as it may be amended or supplemented from time
to time.
THIS PRESS RELEASE IS NOT AN OFFER TO SELL THE SECURITIES OF ALLIS-CHALMERS AND IT IS NOT
SOLICITING AN OFFER TO BUY THESE SECURITIES.
Cautionary Note Regarding Forward-Looking Statements
The information in this report contains forward-looking statements within the meaning of Section
27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of
1934, as amended. These forward-looking statements include, but are not limited to, comments
pertaining to estimated contract duration. Such statements are subject to risks, uncertainties and
assumptions, including, but not limited to, early termination by the customer pursuant to the
contract or otherwise, cancellation or completion of certain contracts or projects earlier than
expected, operating hazards and other factors described in Bronco Drilling Company, Incs. Annual
Report on Form 10-K filed with the SEC on March 17, 2008, as amended on April 29, 2008, and other
filings with the SEC, which are available free of charge on the SECs website at www.sec.gov.
Bronco cautions you that
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