##### 



Exhibit 2.3
 STOCK PURCHASE AGREEMENT
 By and Among
 BRIDAS INTERNATIONAL HOLDINGS LTD.,
 BRIDAS CENTRAL COMPANY, LTD.,
 ASSOCIATED PETROLEUM INVESTORS LIMITED,
 and
 ALLIS-CHALMERS ENERGY INC.
 Dated as of April 27, 2006




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##### 



TABLE OF CONTENTS
 Article I DEFINITIONS
    
    
    1Section 1.1
    
    Definitions
    
    
    1Article II PURCHASE OF SHARES
    
    
    5Section 2.1
    
    Purchase of Shares
    
    
    5Section 2.2
    
    Adjustments for Changes in Capitalization
    
    
    5Section 2.3
    
    Escrow
    
    
    6Article III THE CLOSING
    
    
    7Section 3.1
    
    Closing
    
    
    7Section 3.2
    
    Closing Actions
    
    
    7Article IV REPRESENTATIONS AND WARRANTIES OF SELLERS
    
    
    8Section 4.1
    
    Organization and Related Matters
    
    
    8Section 4.2
    
    Subsidiaries
    
    
    8Section 4.3
    
    Authority; No Violation
    
    
    9Section 4.4
    
    Consents and Approvals
    
    
    10Section 4.5
    
    Stock Ownership
    
    
    10Section 4.6
    
    Financial Statements
    
    
    11Section 4.7
    
    No Other Broker
    
    
    12Section 4.8
    
    Legal Proceedings
    
    
    12Section 4.9
    
    No Undisclosed Liabilities
    
    
    12Section 4.10
    
    Compliance with Applicable Law
    
    
    12Section 4.11
    
    Absence of Certain Changes
    
    
    13Section 4.12
    
    Intellectual Property
    
    
    14Section 4.13
    
    Benefit Plans
    
    
    14Section 4.14
    
    Taxes
    
    
    15Section 4.15
    
    Contracts
    
    
    16Section 4.16
    
    Assets
    
    
    16Section 4.17
    
    Transactions with Certain Persons
    
    
    17Section 4.17
    
    Environmental Laws
    
    
    17Section 4.19
    
    Insurance
    
    
    17Section 4.20
    
    Real Property
    
    
    19Section 4.21
    
    Receivables
    
    
    20Section 4.22
    
    Labor and Employee Relations
    
    
    20Section 4.23
    
    Certain Employees
    
    
    21Section 4.24
    
    Banks, Brokers and Proxies
    
    
    21Section 4.25
    
    Absence of Certain Business Practices
    
    
    21Section 4.26
    
    Securities Laws
    
    
    22Section 4.27
    
    Customers
    
    
    22Section 4.28
    
    Casualties
    
    
    23Section 4.29
    
    Transfer of Assets
    
    
    23Section 4.30
    
    No Other Representation or Warranties
    
    
    23Article V REPRESENTATIONS AND WARRANTIES OF BUYER
    
    
    23
 i




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##### 



Section 5.1
    
    Organization and Related Matters
    
    
    23Section 5.2
    
    Authority; No Violation
    
    
    23Section 5.3
    
    Capitalization
    
    
    24Section 5.4
    
    Consents and Approvals
    
    
    24Section 5.5
    
    Legal Proceedings
    
    
    25Section 5.6
    
    Investment Intent of Buyer
    
    
    25Section 5.7
    
    Public Disclosure Documents
    
    
    25Section 5.8
    
    Litigation and Liabilities
    
    
    26Section 5.9
    
    Absence of Certain Changes
    
    
    26Section 5.10
    
    Taxes
    
    
    26Section 5.11
    
    Title to Properties
    
    
    27Section 5.12
    
    Insurance
    
    
    27Section 5.13
    
    No Other Broker
    
    
    27Section 5.14
    
    Environmental Laws
    
    
    27Article VI COVENANTS
    
    
    27Section 6.1
    
    Conduct of Business
    
    
    27Section 6.2
    
    Public Announcements
    
    
    31Section 6.3
    
    Expenses
    
    
    31Section 6.4
    
    Buyers Access
    
    
    31Section 6.5
    
    Sellers Access
    
    
    31Section 6.6
    
    Certain Communications
    
    
    32Section 6.7
    
    Regulatory Matters; Third Party Consents
    
    
    32Section 6.8
    
    Further Assurances
    
    
    33Section 6.9
    
    Notification of Certain Matters
    
    
    33Section 6.10
    
    Updated Schedules
    
    
    33Section 6.11
    
    Access To Records After Closing Date
    
    
    34Section 6.12
    
    No Solicitations
    
    
    34Section 6.13
    
    Release
    
    
    34Section 6.14
    
    Non-Competition; Non-Solicitation; Confidentiality
    
    
    34Section 6.15
    
    Investor Rights Agreement
    
    
    36Section 6.16
    
    Termination Fee
    
    
    36Section 6.17
    
    Change of Registered Agent
    
    
    36Section 6.18
    
    Board Representation
    
    
    36Section 6.19
    
    
    
    
    37Article VII TAX MATTERS
    
    
    37Section 7.1
    
    Definitions; Return Filing and Transfer Taxes
    
    
    37Section 7.2
    
    Elections
    
    
    37Section 7.3
    
    Tax Indemnification
    
    
    37Section 7.4
    
    Miscellaneous
    
    
    38Article VIII CONDITIONS TO CLOSING
    
    
    38Section 8.1
    
    Conditions to Buyers Obligations
    
    
    38Section 8.2
    
    Conditions to Sellers Obligations
    
    
    40Section 8.3
    
    Mutual Condition
    
    
    41
 ii




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##### 



Article IX SURVIVAL OF REPRESENTATIONS, WARRANTIES, COVENANTS AND AGREEMENTS; INDEMNIFICATION
    
    
    41Section 9.1
    
    Survival
    
    
    41Section 9.2
    
    Obligation of Sellers to Indemnify
    
    
    42Section 9.3
    
    Obligation of Buyer to Indemnify
    
    
    42Section 9.4
    
    Notice and Opportunity to Defend Against Third Party Claims
    
    
    42Section 9.5
    
    Tax Indemnification
    
    
    43Section 9.6
    
    Limits on Indemnification
    
    
    43Section 9.7
    
    Netting of Losses
    
    
    45Section 9.8
    
    Exclusive Remedies
    
    
    45Article X TERMINATION
    
    
    45Section 10.1
    
    Termination
    
    
    45Section 10.2
    
    Obligations upon Termination
    
    
    46Article XI MISCELLANEOUS
    
    
    46Section 11.1
    
    Amendment
    
    
    46Section 11.2
    
    Entire Agreement
    
    
    46Section 11.3
    
    Interpretation
    
    
    46Section 11.4
    
    Severability
    
    
    46Section 11.5
    
    Notices
    
    
    47Section 11.6
    
    Time of the Essence
    
    
    48Section 11.7
    
    Binding Effect; Persons Benefiting; No Assignment
    
    
    48Section 11.8
    
    Counterparts
    
    
    48Section 11.9
    
    No Prejudice
    
    
    49Section 11.10
    
    Governing Law
    
    
    49Section 11.11
    
    Jurisdiction and Enforcement
    
    
    49Section 11.12
    
    Waiver of Trial by Jury
    
    
    50
 EXHIBITS
 Exhibit A
    
    Investor Rights AgreementExhibit B
    
    Escrow AgreementExhibit C
    
    Letter of CreditExhibit D
    
    Mutual Release
 iii




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##### 



STOCK PURCHASE AGREEMENT
 BIH BCC API Buyer Seller Sellers
 RECITALS
 Shares Company
 Business
   ARTICLE I
DEFINITIONS
 Definitions Section 1.1
 Acquisition Proposal




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##### 



Affiliate
 Agreement
 Business Day
 Buyer
 Capital Expenditures
 Code
 Company
 Company Employee
 Encumbrance provided, however,
 Environmental Laws
 2




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##### 



Environmental Permits
 ERISA
 Exchange Act
 GAAP
 Governmental Authority
 Indebtedness
      Hedging Obligations
  3




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##### 



Investor Rights Agreement Exhibit A
 Loss
 Material Adverse Effect provided that, Section 8.1 Section 8.2
 Person
 Restricted Area
 SEC
 Securities Act
 Seller Sellers
 Sellers Knowledge to the knowledge of any Seller
 Shares
 Subsidiaries Subsidiary Schedule 1.1(a) (b) Schedule
1.1(a)
 4




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##### 



Tax
 Tax Return
 Taxing Authority Administración Federal de Ingresos Públicos Servicio de Impuestos Nacionales
 Wire Transfer
 ARTICLE II
PURCHASE OF SHARES
 Purchase of Shares Cash
Consideration Buyer Common Stock Stock Consideration Purchase Price
 Adjustments for Changes in Capitalization
 5




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##### 



Escrow
 Article VII Article IX Escrow
Agent Escrow Termination Date Exhibit B Escrow Agreement provided, however Exhibit
C Section 2.3
 Article VII Article VII Post Termination Date Cap Amount Confirmation Letter
 6




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##### 



ARTICLE III
THE CLOSING
 Closing Closing th Article VIII Closing Date
 Closing Actions
     Section 2.3
 Section 6.18
 7




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##### 



Article VIII
  ARTICLE IV
REPRESENTATIONS AND WARRANTIES OF SELLERS
 provided, however, Section
4.1(b) Section 4.3(a) Section 4.3(b) Section 4.5(b)
 Organization and Related Matters
 Schedule 4.1(a)
   DLS Drilling Logistics and Services Corporation DLS Argentina Limited
 Subsidiaries
 8




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##### 



Schedule 4.2(a)
  Schedule 4.2(c)
 Authority; No Violation
 Seller Transaction Documents
  9




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##### 



Consents and Approvals
 Schedule 4.4
 Stock Ownership
  10




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##### 



Financial Statements
 Company GAAP Financial
Statements Interim Financial
Statements Schedule 4.6
   11




---



##### 



No Other Broker Section 6.3
 Legal Proceedings Schedule 4.8
 No Undisclosed Liabilities Schedule 4.9 Section 6.1(a)
 Compliance with Applicable Law
 Permits Section 4.18 Schedule 4.10(a) Schedule
4.10(a)
 12




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##### 



Schedule 4.10(b)
 Absence of Certain Changes
         13




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##### 



Section 4.11
 Intellectual Property
 Schedule 4.12 Intellectual Property Asset
 Benefit Plans
 Schedule 4.23 Schedule 4.13(a) Benefit Plans
  14




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##### 



Taxes
  Schedule 4.14 Schedule 4.14
      Schedule 4.14(h)
  15




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##### 



Contracts
 Schedule 4.15(a) Contracts
    Assets
 Schedule 4.16(a) Schedule 4.16(a) Schedule
4.16(a)
 16




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##### 



Section 4.16(a) Schedule 4.16(a)
  Transactions with Certain Persons Schedule
4.17
 Environmental Laws
 Insurance
  17




---



##### 



Schedule 4.19(b)
   Schedule 4.19(c)
          18




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##### 



Real Property
 Schedule 4.20(a) Owned Real Property Schedule 4.20(a)
 Schedule 4.20(b) Leases
 Schedule 4.20 (b)
 19




---



##### 



Receivables Receivables Schedule 4.21
 Labor and Employee Relations
 Schedule 4.22 Schedule 4.22
   Schedule 4.22(d)
  20




---



##### 



Schedule 4.22(i)
 Certain Employees Schedule 4.23
 Banks, Brokers and Proxies Schedule 4.24
    Absence of Certain Business Practices
 21




---



##### 



Securities Laws
   Section 5.7
 Customers Schedule 4.27
 22




---



##### 



Casualties
 Transfer of Assets Schedule 4.8 Section 4.29 Schedule 4.29
 No Other Representation or Warranties ARTICLE IV
 ARTICLE V
REPRESENTATIONS AND WARRANTIES OF BUYER
  Organization and Related Matters
 Authority; No Violation
 Buyer Transaction Documents
 23




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##### 



Capitalization
 Buyer
Preferred Stock
   Consents and Approvals Schedule 5.4
 24




---



##### 



Legal Proceedings
 Investment Intent of Buyer
 Public Disclosure Documents
 Buyer Reports
 25




---



##### 



Litigation and Liabilities
 Absence of Certain Changes
 Taxes
 26




---



##### 



Title to Properties
 Insurance
 No Other Broker
 Environmental Laws
 ARTICLE VI
COVENANTS
 Conduct of Business
   27




---



##### 



28




---



##### 



29




---



##### 



30




---



##### 



Public Announcements provided, however
 Expenses
 Buyers Access
 Sellers Access
 31




---



##### 



Certain Communications
 Regulatory Matters; Third Party Consents
   32




---



##### 



Further Assurances
 Notification of Certain Matters
 Updated Schedules
 Updated Schedules Section 8.1(a)
 Section 6.10
 33




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##### 



Section 6.10
 Access To Records After Closing Date
 No Solicitations Seller
Representatives Section 6.12 Section 6.12
 Release Exhibit B Mutual
Release
 Non-Competition; Non-Solicitation; Confidentiality
 34




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##### 



Non-Compete Restricted Period
 Non-Solicitation provided, however
 Confidential Information Section 6.14(c)
 Specific Performance Section 6.14 Section 6.14 Section 6.14
 35




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##### 



Reasonableness of Covenants Section 6.14
 Investor Rights Agreement Exhibit A
 Termination Fee
 Section 10.1(a)(iii) Article IV
 Section 10.1(a)(iv) Section 10.1(a)(iv) Section
8.1(j)
 Section 6.16 Section 6.16 Section 6.16 Section 6.16 Section 6.16
 Change of Registered Agent
 Board Representation
   36




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##### 



provided, however
  Article IV
 ARTICLE VII
TAX MATTERS
 Definitions; Return Filing and Transfer Taxes
  , Tax Deficiency Schedule 4.14
  Elections
 Tax Indemnification
 37




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##### 



Section 4.14 Article VII
 Section 7.3(a) provided, however
 Article VII provided, however Section
9.6(a) Section 9.6(b) Article VII
 Miscellaneous Article VII
 ARTICLE VIII
CONDITIONS TO CLOSING
 Conditions to Buyers Obligations Section 8.3
  38




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##### 



provided, however
  Section
8.1(a) Section 8.1(b)
    Section 8.1(g)
  Section 3.2(h)
  39




---



##### 



Conditions to Sellers Obligations Section 8.3
 provided, however
  Section 8.2(a) Section 8.2(b)
  40




---



##### 



Section 8.2(f)
 Schedule 4.4
  Schedule 8.2(i)
     Mutual Condition
 ARTICLE IX
SURVIVAL OF REPRESENTATIONS, WARRANTIES,
COVENANTS AND AGREEMENTS; INDEMNIFICATION
 Survival
 provided, however Section 4.1 Section 4.2 Section 4.3 Section 4.5 Section 5.1 Section 5.2 Section 4.13
 41




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##### 



Section 4.14 Section 9.1(a)
  Section 10.1(a)(iii) Section
6.16(a)
  Obligation of Sellers to Indemnify Section 9.1 Section 9.6
 Obligation of Buyer to Indemnify Section 9.1 Section 9.6
 Notice and Opportunity to Defend Against Third Party Claims
 42




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##### 



Indemnitee Asserted Liability Claims Notice Section 9.2 Indemnifying Party provided, however Section 9.4 Section
9.1
 provided, however
 Tax Indemnification Article
IX Article VII Section 4.14 Article VII Section 9.1 Section 9.6(a) and (b) Article VII Article VII Section 9.6(a) Section
9.6(b)
 Limits on Indemnification
 Article VII Section 9.2 Section 9.3 Threshold Article VII Section 9.2 Section 9.3
 43




---



##### 



provided, however Section 9.6(a) Section 4.1 Section 4.2 Section 4.3 Section 4.5 Section 4.29 Article VII Article
IX
 Article VII Article IX provided, however Section 9.6(b) Section 4.1 Section 4.2 Section 4.3 Section 4.5 Section 4.29 Section 4.29 Section
9.6(b) Section 2.3 provided, however Article IV provided, further, however Section 9.6(b) Section 9.6(b) Section 2.3 Section 2.3(b) Article IV
 Article IX provided, however Section 9.6(c)
 44




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##### 



Netting of Losses
 Article IX Section 9.2 Section 9.3 Section 9.2 Section
9.3 Article IX Article IX
 Exclusive Remedies
 Article IX Article VII
 ARTICLE X
TERMINATION
 Termination
   Article VIII provided, however Article VIII
 Article
VIII provided,
however
 45




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##### 



Article VIII
 provided, however
  Obligations upon Termination Section 10.1 Section 6.2 Section 6.3 Section
6.16 Section 9.1(c)
 ARTICLE XI
MISCELLANEOUS
 Amendment
 Entire Agreement
 Interpretation
 Severability
 46




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##### 



Notices
  
  
  
  
 47




---



##### 



Time of the Essence
 Binding Effect; Persons Benefiting; No Assignment provided, however,
 Counterparts
 48




---



##### 



No Prejudice
 Governing Law
 Jurisdiction and Enforcement
 Section 11.5 Section 11.5
 49




---



##### 



Waiver of Trial by Jury
  50




---



##### 



BRIDAS INTERNATIONAL HOLDINGS LTD.By:
    
    /s/ Nestor Hugo FaliveneName:
    
    Nestor Hugo FaliveneTitle:
    
    Attorney-In-FactBRIDAS CENTRAL COMPANY LTD.By:
    
    /s/ Giovanni DellOrtoName:
    
    Giovanni DellOrtoTitle:
    
    Attorney-In-FactASSOCIATED PETROLEUM INVESTORS LIMITEDBy:
    
    /s/ Alejandro Pedro BulgheroniName:
    
    Alejandro Pedro BulgheroniTitle:
    
    Attorney-In-FactALLIS-CHALMERS ENERGY INC.By:
    
    /s/ Munawar H. HidayatallahName:
    
    Munawar H. HidayatallahTitle:
    
    Chairman of the Board and ChiefExecutive Officer
 51




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##### 



EXHIBIT A  to Stock Purchase Agreement
 
 Agreement Company Exhibit A Investors
 Stock Purchase Agreement Common Stock
   Definitions
 Agreement
 Beneficially Own Beneficially Owned Beneficial Ownership Beneficial Owner Beneficially Owned
 Blackout Period




---



##### 



provided provided, further minus
 Board
 Business Day
 Closing Date
 Common Stock
 Company
 Designation Rights Termination Date
 Effectiveness Period
 Equity Securities Offering
 Exchange Act
 Family Member
 Form S-1
 Form S-3
 2




---



##### 



Holder
 Inspector
 Investor
 Investor Director
 Market Standoff Period provided, however provided further
 NASD
 Permitted Assignee
 register registered registration
 Registrable Securities
 Registration Expenses
 Registration Statement
 3




---



##### 



Relevant Security
 SEC
 SEC Effective Date
 Securities Act
 Selling Expenses
 Shares
 Stock Purchase Agreement
 Transfer
 Board Designation Rights
 Designation
 Termination of Designation Rights Designation Rights Termination Date
 Company Support
 4




---



##### 



Vacancies
 Market Standoff
 Transfer provided however
  5




---



##### 



Registration Rights
 Shelf Registration Statement Registration Statement provided however
 Registration Procedures
 provided however Effectiveness Period
 6




---



##### 



provided however
  7




---



##### 



provided however
 8




---



##### 



Suspension of Offers and Sales
 9




---



##### 



Registration Expenses Registration Expenses Selling Expenses
 Information by Holder
 Indemnification
  10




---



##### 



Marketing
Materials provided
  11




---



##### 



provided however
 provided however
   12




---



##### 



Miscellaneous
 Assignment of Rights; Successors and Permitted Assignees provided however
 Notices
 If to the Company:
    
    Allis Chalmers Energy Inc.5075 Westheimer, Suite 890Houston, Texas 77056Attention: Theodore F. Pound, General CounselFacsimile: (713) 369-0555
 13




---



##### 



with a copy (which shall not constitute notice) to:
    
    Andrews Kurth LLP600 Travis, Suite 4200Houston, Texas 77002Attention: Robert V. JewellFacsimile: (713) 238-7135If to the Investors:
    
    To each Investor at its address set forth on Exhibit Awith a copy (which shall not constitute notice) to:
    
    Akin Gump Strauss Hauer & Feld LLP1111 Louisiana Street , 44th FloorHouston, Texas 77002Attention: Jack LangloisFacsimile: (713) 236-0822
  Specific Performance
 Counterparts
 Amendments
 Headings and Cross References
 Severability
 Entire Agreement
 14




---



##### 



Governing Law
  15




---



##### 



THE COMPANY:ALLIS-CHALMERS ENERGY INC.By:Name:
    
    Munawar H. HidayatallahTitle:
    
    Chief Executive OfficerINVESTORS:BRIDAS INTERNATIONAL HOLDINGS LTD.By:Name:Title:BRIDAS CENTRAL COMPANY, LTD.By:Name:Title:ASSOCIATED PETROLEUM INVESTORS LIMITEDBy:Name:Title:




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##### 



EXHIBIT A  to Investors Rights Agreement
 Investor Information
 Name
    
    AddressBridas International Holdings Ltd.
    
    Beaufort House, Road TownTortola , British Virgin IslandFacsimile: 1-284-494-2704Attention: Mr. Atilio Martín PalmeiroWith a concurrent copy (which shall not constitute notice) to:Interservices Management Company LimitedAvda. Leandro N. Alem 1134, Piso 14(C1001AAT) Buenos Aires, ArgentinaFacsimile: 54 -11- 4310-4598Attention: Mr. Silvestre AsureyBridas Central Company, Ltd.
    
    Beaufort House, Road TownTortola , British Virgin IslandFacsimile: 1-284-494-2704Attention: Mr. Giovanni Dell OrtoWith a concurrent copy (which shall not constitute notice) to:Bridas Energy International SpAVia Valtellina 17  7° piano20159 Milano, ItalyFacsimile: 39-02- 69556617Attention: Nestor Hugo FaliveneAssociated Petroleum Investors Limited
    
    Beaufort House, Road TownTortola , British Virgin IslandFacsimile: 1-284-494-2704Attention: Mr. Manuel Horacio BañaWith a concurrent copy (which shall not constitute notice) to:Interservices Management Company LimitedAvda. Leandro N. Alem 1134, Piso 14(C1001AAT) Buenos Aires, ArgentinaFacsimile: 54 -11- 4312-9205Attention: Mr. Alejandro Pedro Bulgheroni




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##### 



EXHIBIT B  to Stock Purchase Agreement
 FORM OF
ESCROW AGREEMENT
     Appointment
 Escrow Shares; Stock Powers provided that
 Substitute for the Escrow Shares provided that




---



##### 



provided that provided further,
that
 Distribution in Respect of Sellers Indemnities under the Stock Purchase Agreement
  2
            3




---



##### 



Valuing the Shares to be Released from Escrow
 Escrow Termination Date provided that
 4




---



##### 



Escrow Agent
 Succession
 Fees
 5




---



##### 



Indemnity
 Account Opening Information/TINs
  For accounts opened in the US
  For non-US accounts
  TINs
  6




---



##### 



Notices
     Security Procedures
 7




---



##### 



Miscellaneous
 [Remainder of Page Intentionally Left Blank]
 8




---



##### 



ESCROW AGENT:JPMORGAN CHASE BANK, N.A.By:Name:Title:BUYER:ALLIS-CHALMERS ENERGY, INC.By:Name:Title:SELLERS:BRIDAS INTERNATIONAL HOLDINGS LTD.By:Name:Title:BRIDAS CENTRAL COMPANY LTD.By:Name:Title:ASSOCIATED PETROLEUM INVESTORS LIMITEDBy:Name:Title:




---



##### 



Schedule 1  to Escrow Agreement
 Effective Date: []Name of Buyer: ALLIS-CHALMERS ENERGY INC.Buyer Notice Address: 5075 Westheimer, Suite 890Houston, Texas 77056Facsimile: (713) 369-0555Attn: Theodore F. Pound, General CounselBuyer TIN: []
 Buyer Wiring Instructions:
    
    [][][][]
  Sellers Notice Addresses:
    
    ASSOCIATED PETROLEUM INVESTORS LTDBeaufort House, Road Town,Tortola , British Virgin IslandFacsimile: 1-284-494-2704Attention: Mr. Manuel Horacio BañaSeller TIN: []With a concurrent copy (which shall not constitute notice) to:Interservices Management Company LimitedAvda. Leandro N. Alem 1134, Piso 14(C1001AAT) Buenos Aires, ArgentinaFacsimile: 54 -11- 4312-9205Attention: Mr. Alejandro Pedro BulgheroniBRIDAS INTERNATIONAL HOLDINGS LIMITEDBeaufort House, Road Town,Tortola , British Virgin IslandFacsimile: 1-284-494-2704Attention: Mr. Atilio Martín PalmeiroSeller TIN: []With a concurrent copy (which shall not constitute notice) to:
 Schedule 1-1




---



##### 



Interservices Management Company LimitedAvda. Leandro N. Alem 1134, Piso 14(C1001AAT) Buenos Aires, ArgentinaFacsimile: 54 -11- 4310-4598Attention: Mr. Silvestre AsureyBRIDAS CENTRAL COMPANY LTD.Beaufort House, Road Town,Tortola , British Virgin IslandFacsimile: 1-284-494-2704Attention: Mr. Giovanni Dell OrtoSeller TIN: []With a concurrent copy (which shall not constitute notice) to:Bridas Energy International SpAVia Valtellina 17  7° piano20159 Milano, ItalyFacsimile: 39-02- 69556617Attention: Nestor Hugo Falivene
 Sellers Wiring Instructions:
    
    [][][][]
  Investment: A trust account with JPMorgan Chase Bank.Escrow Agent notice address:
    
    JPMorgan Chase Bank N.A.Worldwide Securities Services4 New York Plaza  21st FloorNY, NY 10004Attention: Ms. Sandra FriersonFax No.: 212.623.6168Escrow Agents compensation: US$5,000 per annum without pro-ration for partial years.
 Schedule 1-2




---



##### 



Schedule 2  to Escrow Agreement
 
  Name
    
    Telephone Number
    
    Signature
  Name
    
    Telephone Number
    
    Signature
 Schedule 2-1




---



##### 



EXHIBIT A  to Escrow Agreement
 FORM OF LETTER OF CREDIT
 IF THIS LANGUAGE FOR THE STANDBY LETTER OF CREDIT IS TO BE USED THEN THE OBLIGORS/APPLICANTS
MUST SIGNIFY THEIR APPROVAL BY SIGNING-OFF ON THIS EXHIBIT.
  
 By:
    
    XAUTHORIZED SIGNATURE OF
    
    DATEOBLIGORS/APPLICANTS
 
 TO:
    
    APPLICANT:JPMORGAN CHASE BANK, N.A.
    
    BRIDAS INTERNATIONAL HOLDINGSWORLDWIDE SECURITIES SERVICES
    
    LTD.,4
NEW YORK PLAZA  21ST FLOOR
    
    BRIDAS CENTRAL COMPANY LTD.NY, NY 10004
    
    ANDATTENTION: MS. SANDRA FRIERSON
    
    ASSOCIATED PETROLEUM INVESTORS LIMITEDWE HAVE ESTABLISHED OUR IRREVOCABLE STANDBY LETTER OF CREDIT IN YOUR FAVOR AS DETAILED HEREIN SUBJECT TO ISP98DOCUMENTARY CREDIT NUMBER:DATE OF ISSUE:
    
    (L/C ISSUE DATE)BENEFICIARY:
    
    JPMORGAN CHASE BANK, N.A.
WORLDWIDE SECURITIES SERVICES
4 NEW YORK PLAZA  21ST FLOOR
NY, NY 10004
ATTENTION: MS. SANDRA FRIERSONAPPLICANT:
    
    BRIDAS INTERNATIONAL HOLDINGS 
LTD.,
BRIDAS CENTRAL COMPANY LTD.
AND
ASSOCIATED PETROLEUM INVESTORS
LIMITEDDATE AND PLACE OF EXPIRY:
    
    (EXPIRY DATE) AT OUR COUNTERDOCUMENT CREDIT AMOUNT:
    
    USD(AMOUNT TBD)AVAILABLE WITH:
    
    (ISSUING BANK)
(BRANCH)
BY PAYMENT
 PAGE 1




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##### 



[ISSUING BANK] [ISSUING BANK]
  
 [ISSUING BANK, BRANCH,
SPECIFYING TIME, PLACE (WITHIN THE CONTINENTAL U.S.) AND LOCATION WITHIN THAT PLACE, PERSON TO
WHOM, AND MEDIUM IN WHICH PRESENTATION MUST BE MADE]
     AUTHORIZED SIGNATURE




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##### 



EXHIBIT C  to Stock Purchase Agreement
 FORM OF LETTER OF CREDIT
 IF THIS LANGUAGE FOR THE STANDBY LETTER OF CREDIT IS TO BE USED THEN THE OBLIGORS/APPLICANTS
MUST SIGNIFY THEIR APPROVAL BY SIGNING-OFF ON THIS EXHIBIT.
  
 By:
    
    XAUTHORIZED SIGNATURE OF
    
    DATEOBLIGORS/APPLICANTS
 
 TO:
    
    APPLICANT:JPMORGAN CHASE BANK, N.A.
    
    BRIDAS INTERNATIONAL HOLDINGSWORLDWIDE SECURITIES SERVICES
    
    LTD.,4 NEW YORK PLAZA  21ST FLOOR
    
    BRIDAS CENTRAL COMPANY LTD.NY, NY 10004
    
    ANDATTENTION: MS. SANDRA FRIERSON
    
    ASSOCIATED PETROLEUM INVESTORSLIMITEDWE HAVE ESTABLISHED OUR IRREVOCABLE STANDBY LETTER OF CREDIT IN YOUR FAVOR AS DETAILED HEREIN SUBJECT TO ISP98DOCUMENTARY CREDIT NUMBER:DATE OF ISSUE:
    
    (L/C ISSUE DATE)BENEFICIARY:
    
    JPMORGAN CHASE BANK, N.A.
WORLDWIDE SECURITIES SERVICES
4 NEW YORK PLAZA  21ST FLOOR
NY, NY 10004
ATTENTION: MS. SANDRA FRIERSONAPPLICANT:
    
    BRIDAS INTERNATIONAL HOLDINGS
LTD.,
BRIDAS CENTRAL COMPANY LTD.
AND
ASSOCIATED PETROLEUM INVESTORS LIMITEDDATE AND PLACE OF EXPIRY:
    
    (EXPIRY DATE) AT OUR COUNTERDOCUMENT CREDIT AMOUNT:
    
    USD(AMOUNT TBD)AVAILABLE WITH:
    
    (ISSUING BANK)
(BRANCH)
BY PAYMENT
 PAGE 1




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##### 



[ISSUING BANK] [ISSUING BANK]
  
 [ISSUING BANK, BRANCH,
SPECIFYING TIME, PLACE (WITHIN THE CONTINENTAL U.S.) AND LOCATION WITHIN THAT PLACE, PERSON TO
WHOM, AND MEDIUM IN WHICH PRESENTATION MUST BE MADE]
     AUTHORIZED SIGNATURE




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##### 



EXHIBIT D  to Stock Purchase Agreement
 MUTUAL RELEASE
 Mutual Release     Stock Purchase Agreement BIH BCC API Buyer Seller Sellers
 RECITALS
  Company
 AGREEMENT
  1. Acknowledgement
 2. Release by the Company
 Release of Seller Releasees Seller Releasee Seller
Releasees




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##### 



Company Related Persons provided, however
 No Assertion
 Indemnification
 3. Release by Sellers
 Release of Company Releasees Company Releasee Company Releasees Seller Related Persons provided however




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##### 



No Assertion
 Indemnification
 4. Severability
 5. Amendment; Governing Law
 6. Counterparts
 7. Interpretation Person Affiliate




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##### 



SELLERS:
BRIDAS INTERNATIONAL HOLDINGS LTD.By:Name:Title: STATE OF
    
    
    
    
    ))COUNTY OF
    
    
    
    )
 BEFORE ME,      BRIDAS INTERNATIONAL HOLDINGS LTD.
  Notary PublicCommission Expires:
    
    
    
    (SEAL)




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##### 



BRIDAS CENTRAL COMPANY LTD.By:Name:Title: STATE OF
    
    
    
    
    ))COUNTY OF
    
    
    
    )
 BEFORE ME,      BRIDAS CENTRAL COMPANY LTD.
  Notary PublicCommission Expires:
    
    
    
    (SEAL)




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##### 



ASSOCIATED PETROLEUM INVESTORS
LIMITEDBy:Name:Title: STATE OF
    
    
    
    
    ))COUNTY OF
    
    
    
    )
 BEFORE ME,      ASSOCIATED PETROLEUM INVESTORS LIMITED
  Notary PublicCommission Expires:
    
    
    
    (SEAL)




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##### 



COMPANY:
DLS DRILLING LOGISTICS AND SERVICES CORPORATIONBy:Name:Title: STATE OF
    
    
    
    
    ))COUNTY OF
    
    
    
    )
 BEFORE ME,      DLS DRILLING LOGISTICS AND SERVICES CORPORATION
  Notary PublicCommission Expires:
    
    
    
    (SEAL)




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##### 



LIST OF DISCLOSURE SCHEDULES  to Stock Purchase Agreement
 provided however