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Exhibit
  99.1

| | Gaffney,
        Cline &
        Associates
| | -------------------------------------------



HYDROCARBON
  PROVED RESERVE STATEMENT
  FORYPF S.A. NON OPERATED ARGENTINE
  PROPERTIES
  AS OF SEPTEMBER 30, 2011

Prepared
  forYPF S.A.
  February 2012





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| | Gaffney,
        Cline &
        Associates
| | -------------------------------------------



SECTIONS

INTRODUCTORY LETTER

STATEMENT OF RESERVES

AUDIT PROCESS DESCRIPTION

STATEMENT OF QUALIFICATIONS

SEC DEFINITIONS FOR OIL
  AND GAS RESERVES



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|                             | Gaffney,
      Cline &
      AssociatesGaffney, Cline & Associates, Inc.
      1300 Post Oak Blvd., Suite 1000
      Houston, TX 77056
      Telephone: +1 713 850 9955www.gaffney-cline.com
|---------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|                             |                                                                                                                                                                                             
|C1900.01/RW/CG/
      LT2071 | February
        17, 2012                                                                                                                                                                   





Mr. Aquiles Rattia RegaladoDirector de Reservas, YPF S.A.
  Macacha Güemes 515
  C1106BKK Buenos Aires
  Argentina

Hydrocarbon
  Proved Reserve Statement for YPF S.A
  Non Operated Argentine Properties as of September 30, 2011

Dear Mr. Aquiles Rattia
  Regalado,

This reserve statement
    has been prepared by Gaffney, Cline & Associates (GCA) and issued on February
    17, 2012 at the request of YPF S.A. regarding assets it holds in Argentina.
    These assets comprise the non operated areas of Acambuco, Aguada Pichana,
    Aguaragüe, CAM2A Sur, CNQ7, CNQ7A, El Tordillo, La Yesera, Lindero Atravesado,
    Magallanes, Palmar Largo,Puesto Hernández, Puesto Quiroga La Tapera,
    Ramos, Río Negro Norte, San Roque and Tierra del Fuego, where YPF holds
    different percentages of participation on each field as described below. GCA
    has conducted an independent audit examination as of September 30, 2011, of
    the hydrocarbon liquid and natural gas proved reserves of the mentioned areas.
    This report is intended for inclusion in YPFs filings (20-F, F-3) with
    the United States Securities and Exchange Commission.


On the basis of technical
    and other information made available to us concerning these property units,
    we hereby provide the reserve statements given in the table below.


Statement
  of Remaining Hydrocarbon Volumes
  YPF S.A. Non Operated Properties in Argentina
  As of September 30, 2011

|                   | Gross
      (100%) Field Volumes |  | YPF
        Working Interest Reserves | 
|------------------ | -------------------------------- |  | ------------------------------------- | 
|                   |                                  |  |                                       | 
|                   | Liquids                          |  | Gas                                   | 
|                   | (MMm3)                           |  | (Bm3)                                 | 
|Proved             |                                  | 
|Developed          | 29.1                             |  | 54.4                                  | 
|Undeveloped        | 5.8                              |  | 9.6                                   | 
|                   |                                  |  |                                       | 
|Total
      Proved | 34.9                             |  | 64.0                                  | 
|                   |                                  |  |                                       | 

Note: The totals in the
  following tables could have rounding differences arising from hidden decimals
  of the individual quoted reserve values.



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|C1900.01/RW/CG/
      LT2071 YPF S.A. |  | Gaffney,
      Cline &
      Associates
|------------------------------------- |  | ---------------------------------------



Statement
  of 100% Gross Field Volumes
  YPF S.A. Non Operated Properties in Argentina, as of September 30, 2011

Liquid Hydrocarbon
  Volumes

|                                 | Proved    | 
|-------------------------------- | --------- | 
|                                 | Developed | 
|Area                             | Producing | 
|                                 | Mm3       | 
|Acambuco                         | 807       | 
|Aguada
      Pichana             | 1,902     | 
|Aguaragüe                        | 640       | 
|CNQ 7A                           | 4,761     | 
|CNQ 7                            | 210       | 
|El Tordillo                      | 4,351     | 
|La Tapera
       P.Quiroga      | 119       | 
|La Yesera                        | 228       | 
|Lindero
      Atravesado         | 264       | 
|Magallanes                       | 338       | 
|Palmar
      Largo               | 309       | 
|Puesto
      Hernández           | 2,753     | 
|Puesto
      Hernández Extensión | 2,366     | 
|Ramos                            | 833       | 
|Río
      Negro Norte            | 89        | 
|San Roque                        | 5,720     | 
|Tierra
      del Fuego           | 1,911     | 
|                                 |           | 
|Total                            | 27,602    | 
|                                 |           | 

|(*) | Total hydrocarbon liquids
      reported here include oil, condensate, gasoline, NGL, propane and butane.
|--- | ---------------------------------------------------------------------------------------------------------

Natural Gas
  Volumes

|                                 | Proved    | 
|-------------------------------- | --------- | 
|                                 | Developed | 
|Area                             | Producing | 
|                                 | MMm3      | 
|Acambuco                         | 8,690     | 
|Aguada
      Pichana             | 6,310     | 
|Aguaragüe                        | 2,874     | 
|CNQ 7A                           |           | 
|CNQ 7                            |           | 
|El Tordillo                      | 502       | 
|La Tapera
       P.Quiroga      |           | 
|La Yesera                        | 95        | 
|Lindero
      Atravesado         | 1,176     | 
|Magallanes                       | 1,597     | 
|Palmar
      Largo               | 72        | 
|Puesto
      Hernández           |           | 
|Puesto
      Hernández Extensión |           | 
|Ramos                            | 4,676     | 
|Río
      Negro Norte            | 66        | 
|San Roque                        | 15,586    | 
|Tierra
      del Fuego           | 7,400     | 
|                                 |           | 
|Total                            | 49,046    | 
|                                 |           | 

2

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|C1900.01/RW/CG/
      LT2071 YPF S.A. |  | Gaffney,
      Cline &
      Associates
|------------------------------------- |  | ---------------------------------------

Statement
  of YPF S.A. Working Interest Reserves
  YPF S.A. Non Operated Properties in Argentina, as of September 30, 2011

Liquid Hydrocarbon
  Volumes

|                                 | Proved    | 
|-------------------------------- | --------- | 
|                                 | Developed | 
|Area                             | Producing | 
|                                 | Mm3       | 
|Acambuco                         | 182       | 
|Aguada
      Pichana             | 519       | 
|Aguaragüe                        | 192       | 
|CNQ 7A                           | 2,381     | 
|CNQ 7                            | 63        | 
|El Tordillo                      | 531       | 
|La Tapera
       P.Quiroga      | 15        | 
|La Yesera                        | 80        | 
|Lindero
      Atravesado         | 99        | 
|Magallanes                       | 184       | 
|Palmar
      Largo               | 93        | 
|Puesto
      Hernández           | 1,694     | 
|Puesto
      Hernández Extensión | 2,366     | 
|Ramos                            | 422       | 
|Río
      Negro Norte            | 31        | 
|San Roque                        | 1,951     | 
|Tierra
      del Fuego           | 573       | 
|                                 |           | 
|Total                            | 11,375    | 
|                                 |           | 

|(*) | Total hydrocarbon liquids
      reported here include oil, condensate, gasoline, NGL, propane and butane.
|--- | ---------------------------------------------------------------------------------------------------------

Natural Gas
  Volumes

|                                 | Proved    | 
|-------------------------------- | --------- | 
|                                 | Developed | 
|Area                             | Producing | 
|                                 | MMm3      | 
|Acambuco                         | 1,955     | 
|Aguada
      Pichana             | 1,721     | 
|Aguaragüe                        | 862       | 
|CNQ 7A                           |           | 
|CNQ 7                            |           | 
|El Tordillo                      | 61        | 
|La Tapera
       P.Quiroga      |           | 
|La Yesera                        | 33        | 
|Lindero
      Atravesado         | 441       | 
|Magallanes                       | 910       | 
|Palmar
      Largo               | 22        | 
|Puesto
      Hernández           |           | 
|Puesto
      Hernández Extensión |           | 
|Ramos                            | 2,371     | 
|Río
      Negro Norte            | 23        | 
|San Roque                        | 5,316     | 
|Tierra
      del Fuego           | 2,220     | 
|                                 |           | 
|Total                            | 15,936    | 
|                                 |           | 

3

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|C1900.01/RW/CG/
      LT2071 YPF S.A. |  | Gaffney,
      Cline &
      Associates
|------------------------------------- |  | ---------------------------------------

Hydrocarbon liquid volumes
    represent crude oil, condensate, gasoline and NGL estimated to be recovered
    during field separation and plant processing and are reported in thousands
    of stock tank cubic meters. Natural gas volumes represent expected gas sales,
    and are reported in millions of cubic meters (at standard conditions of 15
    degrees Celsius and 1 atmosphere). The volumes have not been reduced for fuel
    usage in the field. Based on the interpretation that Argentine royalties are
    a financial obligation or substantially equivalent to a production or similar
    tax, royalties payable to the provinces have not been deducted from the reported
    volumes. The following table presents consumption gas, as a percentage of
    produced gas for each area.


|                         | Consumed
        gas | 
|------------------------ | -------------------- | 
|Area                     | %                    | 
|Acambuco                 | 1.75                 | 
|Aguada
      Pichana     | 2.92                 | 
|Aguaragüe                | 4.67                 | 
|El Tordillo              | 100.00               | 
|La Yesera                | 10.73                | 
|Lindero
      Atravesado | 7.50                 | 
|Magallanes               | 4.85                 | 
|Palmar
      Largo       | 100.00               | 
|Ramos                    | 3.52                 | 
|Río
      Negro Norte    | 31.00                | 
|San Roque                | 1.72                 | 
|Tierra
      del Fuego   | 7.98                 | 

Gas reserves sales volumes
    are based on firm and existing gas contracts, or on the reasonable expectation
    that any such existing gas sales contracts will be renewed on similar terms
    in the future.


Appendix I contains the
    statement of reserves for each unit area.


It is our understanding
    that the proved reserves estimated in this report constitute approximately
    21.4% percent of YPFs Proved Reserves; it is also our understanding
    that the Proved Undeveloped Reserves estimated in this report constitute approximately
    10.9% percent of all YPFs Proved Undeveloped Reserves as of September
    30, 2011. These proportions are on a barrel oil equivalent (BOE) basis. GCA
    is not in a position to verify this statement as it was not requested to review
    YPFs other oil and and gas assets. Our study was completed on February
    10, 2012.


A description of the individual
    assets reserve estimation methodology and the main differences between GCA
    and YPF interpretations are presented in Appendix II.


This audit examination
    was based on reserve estimates and other information provided by YPF to GCA
    through February 10, 2012 and included such tests, procedures and adjustments
    as were considered necessary under the circumstances to prepare the report.
    All questions that arose during the course of the audit process were resolved
    to our satisfaction. GCA believes that the assumptions, data, methods and
    procedures used in connection with the preparation of this report are appropriate
    for the purpose served by the report.


The economic tests for
    the September 30, 2011 Reserve volumes were based on realized crude oil, condensate,
    NGL and average gas sales prices as shown in the following table, as advised
    by YPF. A prior twelve-month first-day-of-the-month average price for West
    Texas Intermediate (WTI) crude of US$94.31/Bbl serves as the foundation for
    the oil, condensate and gasoline price. YPF is subject to extensive regulations
    relating to the oil and


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|C1900.01/RW/CG/
      LT2071 YPF S.A. |  | Gaffney,
      Cline &
      Associates
|------------------------------------- |  | ---------------------------------------

gas industry in Argentina
  which include specific natural gas market regulations as well as hydrocarbon
  export taxes that apply until 2017 according to Law 26,217, all of which affect
  the realized prices of oil and other products in the domestic market. As a result,
  crude oil prices used to determine reserves are set at the beginning of every
  month until 2011, for crude oils of different quality produced by YPF, considering
  the realized prices for crude oils of such quality in the domestic market, taking
  into account the effects of Law 26,217. Additionally, a significant portion
  of the Argentine gas market is regulated. Natural gas prices for the residential
  and power generation segments, as well as natural gas for vehicles, are regulated
  by the government. Natural gas prices for industrial consumers are negotiated
  by market participants on a private basis. As a result, there are no benchmark
  market natural gas prices available in Argentina. GCA audited and accepted the
  methodology and prices used by YPF in estimating the reserves in Argentina.
  In addition, YPF increments the crude oil, condensate and gasoline price in
  2017 due to the scheduled expiration of the export retention tax mentioned above.
  Caution is advised in this regard as the export tax has been scheduled to expire
  several times in the recent past but extended as the deadline approached. Maintaining
  the current price would no doubt have an impact on the reserves estimates.

|                                 | Prices                                                  | 
|-------------------------------- | ------------------------------------------------------- | 
|Area                             | Crude
        Oil Condensate Gasoline
        2011-2016 | 
|                                 | US$/Bbl                                                 | 
|Acambuco                         | 56.42                                                   | 
|Aguada
      Pichana             | 60.93                                                   | 
|Aguaragüe                        | 56.42                                                   | 
|CNQ 7A                           | 59.80                                                   | 
|CNQ 7                            | 61.35                                                   | 
|El Tordillo                      | 56.42                                                   | 
|La Tapera
       P.Quiroga      | 56.42                                                   | 
|La Yesera                        | 61.35                                                   | 
|Lindero
      Atravesado         | 60.93                                                   | 
|Magallanes                       | 58.77                                                   | 
|Palmar
      Largo               | 56.42                                                   | 
|Puesto
      Hernández           | 61.35                                                   | 
|Puesto
      Hernández Extensión | 61.35                                                   | 
|Ramos                            | 56.42                                                   | 
|Río
      Negro Norte            | 61.35                                                   | 
|San Roque                        | 60.93                                                   | 
|Tierra
      del Fuego           | 58.77                                                   | 

Future capital costs were
    derived from development program forecasts prepared by YPF for the fields.
    Recent historical operating expense data were utilized as the basis for operating
    cost projections. GCA has found that YPF has projected sufficient capital
    investments and operating expenses to produce economically the projected volumes


It is GCAs opinion
    that the estimates of total remaining recoverable hydrocarbon liquid and gas
    volumes at September 30, 2011, are, in the aggregate, reasonable and the reserves
    categorization is appropriate and consistent with the definitions for reserves
    set out in 17-CFR Part 210 Rule 4-10(a) of Regulation S-X of the United States
    Securities and Exchange Commission (as set out in Appendix IV). GCA concludes
    that the methodologies employed by YPF in the derivation of the volume estimates
    are appropriate and that the quality of the data relied upon, the depth and
    thoroughness of the estimation process is adequate.


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|C1900.01/RW/CG/
      LT2071 YPF S.A. |  | Gaffney,
      Cline &
      Associates
|------------------------------------- |  | ---------------------------------------

GCA is not aware of any
    potential changes in regulations applicable to these fields that could affect
    the ability of YPF to produce the estimated reserves.


This assessment has been
    conducted within the context of GCA's understanding of YPF's petroleum property
    rights as represented by YPF's management. GCA is not in a position to attest
    to property title, financial interest relationships or encumbrances thereon
    for any part of the appraised properties or interests.


There are numerous uncertainties
    inherent in estimating reserves and resources, and in projecting future production,
    development expenditures, operating expenses and cash flows. Oil and gas reserve
    engineering and resource assessment must be recognized as a subjective process
    of estimating subsurface accumulations of oil and gas that cannot be measured
    in an exact way. Estimates of oil and gas reserves or resources prepared by
    other parties may differ, perhaps materially, from those contained within
    this report. The accuracy of any reserve or resource estimate is a function
    of the quality of the available data and of engineering and geological interpretation.
    Results of drilling, testing and production that post-date the preparation
    of the estimates may justify revisions, some or all of which may be material.
    Accordingly, reserve and resource estimates are often different from the quantities
    of oil and gas that are ultimately recovered, and the timing and cost of those
    volumes that are recovered may vary from that assumed.


For this assignment, GCA
    served as independent reserve auditors. The firm's officers and employees
    have no direct or indirect interest holdings in the property units evaluated.
    GCA's remuneration was not in any way contingent on reported reserve estimates.
    The qualifications of the technical person primarily responsible for overseeing
    this audit are included in Appendix III.


This report has been prepared
    at the request of YPF regarding assets it holds in Argentina and is for inclusion
    in YPFs filings with the United States Securities and Exchange Commission.


Yours sincerelyGaffney, Cline & Associates

/s/ Cesar
  E. Guzzetti

Cesar
  E. GuzzettiGeneral Manager  Latin America Southern Cone

Enclosures:

|Appendix
      I:   | Statement
        of Reserves       | 
|------------------- | ----------------------------------- | 
|Appendix
      II:  | Audit
        Process Description   | 
|Appendix
      III: | Statement
        of Qualifications | 
|Appendix
      IV:  | SEC
        Reserve Definitions     | 

6

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|C1900.01/RW/CG/
      LT2071 YPF S.A. |  | Gaffney,
      Cline &
      Associates
|------------------------------------- |  | ---------------------------------------



APPENDIX
  I
  STATEMENTS OF RESERVES



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|C1900.01/RW/CG/
      LT2071 YPF S.A. |  | Gaffney,
      Cline &
      Associates
|------------------------------------- |  | ---------------------------------------



TABLE
  OF CONTENTS

|                                     | Page
      No. | 
|------------------------------------ | -------------- | 
|TOTAL                                | 1              | 
|UTE Acambuco                         | 2              | 
|UTE Aguada
      Pichana             | 3              | 
|UTE Aguaragüe                        | 4              | 
|UTE CNQ7A                            | 5              | 
|UTE CNQ7                             | 6              | 
|UTE El
      Tordillo                | 7              | 
|UTE La
      Tapera/Puesto Quiroga   | 8              | 
|UTE La
      Yesera                  | 9              | 
|UTE Lindero
      Atravesado         | 10             | 
|UTE Magallanes                       | 11             | 
|UTE Palmar
      Largo               | 12             | 
|UTE Puesto
      Hernández           | 13             | 
|UTE Puesto
      Hernández Extensión | 14             | 
|UTE Ramos                            | 15             | 
|UTE Río
      Negro Norte            | 16             | 
|UTE San
      Roque                  | 17             | 
|UTE Tierra
      del Fuego           | 18             | 

1

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YPF S.A.
  Non Operated Areas

---

(Field /
  Area Name)

Crude
  Oil and Natural Gas Reserve Statement
  Reserves Certification @ September 30, 2011
  for YPF S.A.

A. Cumulative Production to September 30, 2011

| | Oil     |  |           |  |         |  |        |  | Gas      | 
| | ------- |  | --------- |  | ------- |  | ------ |  | -------- | 
| | Primary |  | Secondary |  | Total   |  | Cond.  |  | Gasoline | 
| | Mm3     |  | Mm3       |  | Mm3     |  | Mm3    |  | Mm3      | 
| | 98,591  |  | 55,442    |  | 154,033 |  | 44,700 |  | 4,497    | 

|B. | Gross Field Reserves
      @ September 30, 2011
|-- | -----------------------------------------------

|                          | Oil     |  |           |  |        |  |       |  | Gas      |  |      
|------------------------- | ------- |  | --------- |  | ------ |  | ----- |  | -------- |  | -----
|                          | Primary |  | Secondary |  | Total  |  | Cond. |  | Gasoline |  | LPG  
|                          | Mm3     |  | Mm3       |  | Mm3    |  | Mm3   |  | Mm3      |  | Mm3  
|Proved                    |         | 
|Developed
      Prod.     | 5,336   |  | 11,582    |  | 16,918 |  | 2,567 |  | 993      |  | 7,124
|Developed
      Non-Prod. | 883     |  |           |  | 883    |  | 17    |  | 71       |  | 568  
|Undeveloped               | 1,227   |  | 3,451     |  | 4,678  |  | 928   |  | 5        |  | 160  
|                          |         |  |           |  |        |  |       |  |          |  |      
|Sub-total
      Proved    | 7,446   |  | 15,033    |  | 22,478 |  | 3,512 |  | 1,069    |  | 7,853
|                          |         |  |           |  |        |  |       |  |          |  |      

|C. | YPF S.A. Working
      Interest Reserves @ September 30, 2011
|-- | -------------------------------------------------------------

|                          | Oil     |  |           |  |        |  |       |  | Gas      |  |      
|------------------------- | ------- |  | --------- |  | ------ |  | ----- |  | -------- |  | -----
|                          | Primary |  | Secondary |  | Total  |  | Cond. |  | Gasoline |  | LPG  
|                          | Mm3     |  | Mm3       |  | Mm3    |  | Mm3   |  | Mm3      |  | Mm3  
|Proved                    |         | 
|Developed
      Prod.     | 1,521   |  | 6,360     |  | 7,882  |  | 812   |  | 312      |  | 2,369
|Developed
      Non-Prod. | 494     |  |           |  | 494    |  | 5     |  | 19       |  | 155  
|Undeveloped               | 201     |  | 1,656     |  | 1,857  |  | 217   |  | 1        |  | 47   
|                          |         |  |           |  |        |  |       |  |          |  |      
|Sub-total
      Proved    | 2,216   |  | 8,016     |  | 10,232 |  | 1,033 |  | 333      |  | 2,571
|                          |         |  |           |  |        |  |       |  |          |  |      

|D. Notes:
|---------

| |                       | 
| | --------------------- | 
| | GCA
        Engineer: | 
| |                       | 
| | Approved:             | 
| |                       | 
| | Date:                 | 
| |                       | 



| | Page
        1 | Gaffney,
        Cline & Associates
| | -------------- | -----------------------------------




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UTE Acambuco

---

(Field /
  Area Name)

Crude
  Oil and Natural Gas Reserve Statement
  Reserves Certification @ September 30, 2011 
  for YPF S.A.

|Basin:    |  | Noroeste                    |  | YPF
        S.A. Oil Interest: |  | 22.50% | 
|--------- |  | --------------------------- |  | ------------------------------ |  | ------ | 
|          |  |                             |  |                                |  |        | 
|Province: |  | Salta                       |  | YPF
        S.A. Gas Interest: |  | 22.50% | 
|          |  |                             |  |                                |  |        | 
|Country:  |  | Argentina                   |  | Field
        Gas Usage:       |  | 1.75%  | 
|          |  |                             |  |                                |  |        | 
|Operator  |  | Pan
        American Energy |  | Sales
        Gas:             |  | 98.25% | 
|          |  |                             |  |                                |  |        | 
|          |  |                             |  | Royalty:                       |  | 12.00% | 
|          |  |                             |  |                                |  |        | 

|A. | Cumulative Production
      to September 30, 2011
|-- | -------------------------------------------------

| | Oil     |  |           |  |       |  |       |  | Gas      | 
| | ------- |  | --------- |  | ----- |  | ----- |  | -------- | 
| | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline | 
| | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      | 
| | 211     |  |           |  | 211   |  | 2,528 |  |          | 
| |         |  |           |  |       |  |       |  |          | 

|B. | Gross Field Reserves
      @ September 30, 2011
|-- | -----------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 8       |  |           |  | 8     |  | 799   |  |          |  |    
|Developed
      Non-Prod. |         | 
|Undeveloped               |         |  |           |  |       |  | 821   |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 8       |  |           |  | 8     |  | 1,621 |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    

|C. | YPF S.A. Working
      Interest Reserves @ September 30, 2011
|-- | -------------------------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 2       |  |           |  | 2     |  | 180   |  |          |  |    
|Developed
      Non-Prod. |         | 
|Undeveloped               |         |  |           |  |       |  | 185   |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 2       |  |           |  | 2     |  | 365   |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    

|D. | Notes:
|-- | ------

| |                       | 
| | --------------------- | 
| | GCA
        Engineer: | 
| |                       | 
| | Approved:             | 
| |                       | 
| | Date:                 | 
| |                       | 

Page
          2
      Gaffney,
          Cline & Associates






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UTE Aguada
  Pichana

---

(Field /
  Area Name)

Crude
  Oil and Natural Gas Reserve Statement
  Reserves Certification @ September 30, 2011
  for YPF S.A.

|Basin:    |  | Neuquina  |  | YPF
        S.A. Oil Interest: |  | 27.27% | 
|--------- |  | --------- |  | ------------------------------ |  | ------ | 
|          |  |           |  |                                |  |        | 
|Province: |  | Neuquén   |  | YPF
        S.A. Gas Interest: |  | 27.27% | 
|          |  |           |  |                                |  |        | 
|Country:  |  | Argentina |  | Field
        Gas Usage:       |  | 2.92%  | 
|          |  |           |  |                                |  |        | 
|Operator  |  | Total     |  | Sales
        Gas:             |  | 97.08% | 
|          |  |           |  |                                |  |        | 
|          |  |           |  | Royalty:                       |  | 15.00% | 
|          |  |           |  |                                |  |        | 

|A. | Cumulative Production
      to September 30, 2011
|-- | -------------------------------------------------

| | Oil     |  |           |  |       |  |       |  | Gas      | 
| | ------- |  | --------- |  | ----- |  | ----- |  | -------- | 
| | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline | 
| | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      | 
| |         |  |           |  |       |  | 731   |  | 1,614    | 

|B. | Gross Field Reserves
      @ September 30, 2011
|-- | -----------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |      
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | -----
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG  
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3  
|Proved                    |         | 
|Developed
      Prod.     |         |  |           |  |       |  | 48    |  | 206      |  | 1,648
|Developed
      Non-Prod. |         |  |           |  |       |  | 17    |  | 71       |  | 568  
|Undeveloped               |         |  |           |  |       |  | 1     |  | 5        |  | 40   
|                          |         |  |           |  |       |  |       |  |          |  |      
|Sub-total
      Proved    |         |  |           |  |       |  | 66    |  | 282      |  | 2,255
|                          |         |  |           |  |       |  |       |  |          |  |      

|C. | YPF S.A. Working
      Interest Reserves @ September 30, 2011
|-- | -------------------------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     |         |  |           |  |       |  | 13    |  | 56       |  | 449
|Developed
      Non-Prod. |         |  |           |  |       |  | 5     |  | 19       |  | 155
|Undeveloped               |         |  |           |  |       |  | 0     |  | 1        |  | 11 
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    |         |  |           |  |       |  | 18    |  | 77       |  | 615
|                          |         |  |           |  |       |  |       |  |          |  |    

|D. | Notes:
|-- | ------

| |                       | 
| | --------------------- | 
| | GCA
        Engineer: | 
| |                       | 
| | Approved:             | 
| |                       | 
| | Date:                 | 
| |                       | 

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UTE Aguaragüe

---

(Field /
  Area Name)

Crude
  Oil and Natural Gas Reserve Statement
  Reserves Certification @ September 30, 2011 
  for YPF S.A.

|Basin:    |  | Noroeste  |  | YPF
        S.A. Oil Interest: |  | 30.00% | 
|--------- |  | --------- |  | ------------------------------ |  | ------ | 
|          |  |           |  |                                |  |        | 
|Province: |  | Salta     |  | YPF
        S.A. Gas Interest: |  | 30.00% | 
|          |  |           |  |                                |  |        | 
|Country:  |  | Argentina |  | Field
        Gas Usage:       |  | 4.67%  | 
|          |  |           |  |                                |  |        | 
|Operator  |  | Tecpetrol |  | Sales
        Gas:             |  | 95.33% | 
|          |  |           |  |                                |  |        | 
|          |  |           |  | Royalty:                       |  | 12.00% | 
|          |  |           |  |                                |  |        | 

|A. | Cumulative Production
      to September 30, 2011
|-- | -------------------------------------------------

| | Oil     |  |           |  |       |  |        |  | Gas      | 
| | ------- |  | --------- |  | ----- |  | ------ |  | -------- | 
| | Primary |  | Secondary |  | Total |  | Cond.  |  | Gasoline | 
| | Mm3     |  | Mm3       |  | Mm3   |  | Mm3    |  | Mm3      | 
| | 1,437   |  |           |  | 1,437 |  | 18,645 |  |          | 

|B. | Gross Field Reserves
      @ September 30, 2011
|-- | -----------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 42      |  |           |  | 42    |  | 303   |  |          |  | 296
|Developed
      Non-Prod. |         | 
|Undeveloped               |         |  |           |  |       |  | 105   |  |          |  | 121
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 42      |  |           |  | 42    |  | 408   |  |          |  | 416
|                          |         |  |           |  |       |  |       |  |          |  |    

|C. | YPF S.A. Working
      Interest Reserves @ September 30, 2011
|-- | -------------------------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 13      |  |           |  | 13    |  | 91    |  |          |  | 89 
|Developed
      Non-Prod. |         | 
|Undeveloped               |         |  |           |  |       |  | 32    |  |          |  | 36 
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 13      |  |           |  | 13    |  | 122   |  |          |  | 125
|                          |         |  |           |  |       |  |       |  |          |  |    

|D. | Notes:
|-- | ------

| |                       | 
| | --------------------- | 
| | GCA
        Engineer: | 
| |                       | 
| | Approved:             | 
| |                       | 
| | Date:                 | 
| |                       | 

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UTE CNQ
  7A

---

(Field /
  Area Name)

Crude
  Oil and Natural Gas Reserve Statement
  Reserves Certification @ September 30, 2011 
  for YPF S.A.

|Basin:    |  | Neuquina                 |  | YPF
        S.A. Oil Interest: |  | 50.00% | 
|--------- |  | ------------------------ |  | ------------------------------ |  | ------ | 
|          |  |                          |  |                                |  |        | 
|Province: |  | Mendoza/La
        Pampa |  | YPF
        S.A. Gas Interest: |  | 50.00% | 
|          |  |                          |  |                                |  |        | 
|Country:  |  | Argentina                |  | Field
        Gas Usage:       |  |       
|          |  |                          |  |                                |  |        | 
|Operator  |  | Pluspetrol               |  | Sales
        Gas:             |  |       
|          |  |                          |  |                                |  |        | 
|          |  |                          |  | Royalty:                       |  | 15.00% | 
|          |  |                          |  |                                |  |        | 

|A. | Cumulative Production
      to September 30, 2011
|-- | -------------------------------------------------

| | Oil     |  |           |  |       |  |       |  | Gas      | 
| | ------- |  | --------- |  | ----- |  | ----- |  | -------- | 
| | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline | 
| | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      | 
| |         | 

|B. | Gross Field Reserves
      @ September 30, 2011
|-- | -----------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 909     |  | 3,852     |  | 4,761 |  |      
|Developed
      Non-Prod. |         | 
|Undeveloped               | 74      |  | 2,603     |  | 2,677 |  |      
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 983     |  | 6,455     |  | 7,438 |  |       |  |         
|                          |         |  |           |  |       |  |       |  |          |  |    

|C. | YPF S.A. Working
      Interest Reserves @ September 30, 2011
|-- | -------------------------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 455     |  | 1,926     |  | 2,381 |  |      
|Developed
      Non-Prod. |         | 
|Undeveloped               | 37      |  | 1,302     |  | 1,338 |  |      
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 491     |  | 3,227     |  | 3,719 |  |       |  |         
|                          |         |  |           |  |       |  |       |  |          |  |    

|D. | Notes:
|-- | ------

| |                       | 
| | --------------------- | 
| | GCA
        Engineer: | 
| |                       | 
| | Approved:             | 
| |                       | 
| | Date:                 | 
| |                       | 

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UTE CNQ
  7

---

(Field /
  Area Name)

Crude
  Oil and Natural Gas Reserve Statement
  Reserves Certification @ September 30, 2011 
  for YPF S.A.

|Basin:    |  | Neuquina   |  | YPF
        S.A. Oil Interest: |  | 30.00% | 
|--------- |  | ---------- |  | ------------------------------ |  | ------ | 
|          |  |            |  |                                |  |        | 
|Province: |  | Mendoza    |  | YPF
        S.A. Gas Interest: |  | 30.00% | 
|          |  |            |  |                                |  |        | 
|Country:  |  | Argentina  |  | Field
        Gas Usage:       |  |       
|          |  |            |  |                                |  |        | 
|Operator  |  | Pluspetrol |  | Sales
        Gas:             |  |       
|          |  |            |  |                                |  |        | 
|          |  |            |  | Royalty:                       |  | 15.00% | 
|          |  |            |  |                                |  |        | 

|A. | Cumulative Production
      to September 30, 2011
|-- | -------------------------------------------------

| | Oil     |  |           |  |       |  |       |  | Gas      | 
| | ------- |  | --------- |  | ----- |  | ----- |  | -------- | 
| | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline | 
| | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      | 
| | 219     |  | 21        |  | 241   |  |       |  |         
| |         |  |           |  |       |  |       |  |          | 

|B. | Gross Field Reserves
      @ September 30, 2011
|-- | -----------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 81      |  | 129       |  | 210   |  |      
|Developed
      Non-Prod. |         | 
|Undeveloped               | 20      |  |           |  | 20    |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 101     |  | 129       |  | 230   |  |       |  |         
|                          |         |  |           |  |       |  |       |  |          |  |    

|C. | YPF S.A. Working
      Interest Reserves @ September 30, 2011
|-- | -------------------------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 24      |  | 39        |  | 63    |  |      
|Developed
      Non-Prod. |         | 
|Undeveloped               | 6       |  |           |  | 6     |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 30      |  | 39        |  | 69    |  |       |  |         
|                          |         |  |           |  |       |  |       |  |          |  |    

|D. | Notes:
|-- | ------

| |                       | 
| | --------------------- | 
| | GCA
        Engineer: | 
| |                       | 
| | Approved:             | 
| |                       | 
| | Date:                 | 
| |                       | 

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UTE El
  Tordillo

---

(Field /
  Area Name)

Crude
  Oil and Natural Gas Reserve Statement
  Reserves Certification @ September 30, 2011
  for YPF S.A.

|Basin:    |  | San
        Jorge |  | YPF
        S.A. Oil Interest: |  | 12.20%  | 
|--------- |  | ----------------- |  | ------------------------------ |  | ------- | 
|          |  |                   |  |                                |  |         | 
|Province: |  | Chubut            |  | YPF
        S.A. Gas Interest: |  | 12.20%  | 
|          |  |                   |  |                                |  |         | 
|Country:  |  | Argentina         |  | Field
        Gas Usage:       |  |        
|          |  |                   |  |                                |  |         | 
|Operator  |  | Tecpetrol         |  | Sales
        Gas:             |  | 100.00%
|          |  |                   |  |                                |  |         | 
|          |  |                   |  | Royalty:                       |  | 12.00%  | 
|          |  |                   |  |                                |  |         | 

|A. | Cumulative Production
      to September 30, 2011
|-- | -------------------------------------------------

| | Oil     |  |           |  |        |  |       |  | Gas      | 
| | ------- |  | --------- |  | ------ |  | ----- |  | -------- | 
| | Primary |  | Secondary |  | Total  |  | Cond. |  | Gasoline | 
| | Mm3     |  | Mm3       |  | Mm3    |  | Mm3   |  | Mm3      | 
| | 37,588  |  | 9,293     |  | 46,881 |  |       |  |          | 
| |         |  |           |  |        |  |       |  |          | 

|B. | Gross Field Reserves
      @ September 30, 2011
|-- | -----------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 2,050   |  | 2,301     |  | 4,351 |  |       |  |          |  |    
|Developed
      Non-Prod. |         | 
|Undeveloped               | 958     |  | 403       |  | 1,361 |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 3,008   |  | 2,704     |  | 5,712 |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    

|C. | YPF S.A. Working
      Interest Reserves @ September 30, 2011
|-- | -------------------------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 250     |  | 281       |  | 531   |  |       |  |          |  |    
|Developed
      Non-Prod. |         | 
|Undeveloped               | 117     |  | 49        |  | 166   |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 367     |  | 330       |  | 697   |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    

|D. | Notes:
|-- | ------

| |                       | 
| | --------------------- | 
| | GCA
        Engineer: | 
| |                       | 
| | Approved:             | 
| |                       | 
| | Date:                 | 
| |                       | 

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UTE La
  Tapera  P.Quiroga

---

(Field /
  Area Name)

Crude
  Oil and Natural Gas Reserve Statement
  Reserves Certification @ September 30, 2011
  for YPF S.A.

|Basin:    |  | San
        Jorge |  | YPF
        S.A. Oil Interest: |  | 12.20% | 
|--------- |  | ----------------- |  | ------------------------------ |  | ------ | 
|          |  |                   |  |                                |  |        | 
|Province: |  | Chubut            |  | YPF
        S.A. Gas Interest: |  | 12.20% | 
|          |  |                   |  |                                |  |        | 
|Country:  |  | Argentina         |  | Field
        Gas Usage:       |  |       
|          |  |                   |  |                                |  |        | 
|Operator  |  | Tecpetrol         |  | Sales
        Gas:             |  |       
|          |  |                   |  |                                |  |        | 
|          |  |                   |  | Royalty:                       |  | 12.00% | 
|          |  |                   |  |                                |  |        | 

|A. | Cumulative Production
      to September 30, 2011
|-- | -------------------------------------------------

| | Oil     |  |           |  |       |  |       |  | Gas      | 
| | ------- |  | --------- |  | ----- |  | ----- |  | -------- | 
| | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline | 
| | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      | 
| | 268     |  |           |  | 268   |  |       |  |          | 
| |         |  |           |  |       |  |       |  |          | 

|B. | Gross Field Reserves
      @ September 30, 2011
|-- | -----------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 119     |  |           |  | 119   |  |      
|Developed
      Non-Prod. |         | 
|Undeveloped               | 63      |  |           |  | 63    |  |      
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 182     |  |           |  | 182   |  |       |  |         
|                          |         |  |           |  |       |  |       |  |          |  |    

|C. | YPF S.A. Working
      Interest Reserves @ September 30, 2011
|-- | -------------------------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 15      |  |           |  | 15    |  |      
|Developed
      Non-Prod. |         | 
|Undeveloped               | 8       |  |           |  | 8     |  |      
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 22      |  |           |  | 22    |  |       |  |         
|                          |         |  |           |  |       |  |       |  |          |  |    

|D. | Notes:
|-- | ------

| |                       | 
| | --------------------- | 
| | GCA
        Engineer: | 
| |                       | 
| | Approved:             | 
| |                       | 
| | Date:                 | 
| |                       | 

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UTE La
  Yesera

---

(Field /
  Area Name)

Crude
  Oil and Natural Gas Reserve Statement
  Reserves Certification @ September 30, 2011 
  for YPF S.A.

|Basin:    |  | Neuquina          |  | YPF
        S.A. Oil Interest: |  | 35.00% | 
|--------- |  | ----------------- |  | ------------------------------ |  | ------ | 
|          |  |                   |  |                                |  |        | 
|Province: |  | Río
        Negro |  | YPF
        S.A. Gas Interest: |  | 35.00% | 
|          |  |                   |  |                                |  |        | 
|Country:  |  | Argentina         |  | Field
        Gas Usage:       |  | 10.73% | 
|          |  |                   |  |                                |  |        | 
|Operator  |  | Pluspetrol        |  | Sales
        Gas:             |  | 89.27% | 
|          |  |                   |  |                                |  |        | 
|          |  |                   |  | Royalty:                       |  | 12.00% | 
|          |  |                   |  |                                |  |        | 

|A. | Cumulative Production
      to September 30, 2011
|-- | -------------------------------------------------

| | Oil     |  |           |  |       |  |       |  | Gas      | 
| | ------- |  | --------- |  | ----- |  | ----- |  | -------- | 
| | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline | 
| | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      | 
| | 613     |  |           |  | 613   |  |       |  |          | 
| |         |  |           |  |       |  |       |  |          | 

|B. | Gross Field Reserves
      @ September 30, 2011
|-- | -----------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 228     |  |           |  | 228   |  |       |  |          |  |    
|Developed
      Non-Prod. |         | 
|Undeveloped               |         |  |           |  |       |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 228     |  |           |  | 228   |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    

|C. | YPF S.A. Working
      Interest Reserves @ September 30, 2011
|-- | -------------------------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 80      |  |           |  | 80    |  |       |  |          |  |    
|Developed
      Non-Prod. |         | 
|Undeveloped               |         | 
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 80      |  |           |  | 80    |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    

|D. | Notes:
|-- | ------

| |                       | 
| | --------------------- | 
| | GCA
        Engineer: | 
| |                       | 
| | Approved:             | 
| |                       | 
| | Date:                 | 
| |                       | 

Page
          9
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UTE Lindero
  Atravesado

---

(Field /
  Area Name)

Crude
  Oil and Natural Gas Reserve Statement
  Reserves Certification @ September 30, 2011
  for YPF S.A.

|Basin:    |  | Neuquina                    |  | YPF
        S.A. Oil Interest: |  | 37.50% | 
|--------- |  | --------------------------- |  | ------------------------------ |  | ------ | 
|          |  |                             |  |                                |  |        | 
|Province: |  | Neuquén                     |  | YPF
        S.A. Gas Interest: |  | 37.50% | 
|          |  |                             |  |                                |  |        | 
|Country:  |  | Argentina                   |  | Field
        Gas Usage:       |  | 7.50%  | 
|          |  |                             |  |                                |  |        | 
|Operator  |  | Pan
        American Energy |  | Sales
        Gas:             |  | 92.50% | 
|          |  |                             |  |                                |  |        | 
|          |  |                             |  | Royalty:                       |  | 15.00% | 
|          |  |                             |  |                                |  |        | 

|A. | Cumulative Production
      to September 30, 2011
|-- | -------------------------------------------------

| | Oil     |  |           |  |       |  |       |  | Gas      |  
| | ------- |  | --------- |  | ----- |  | ----- |  | -------- | -
| | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  
| | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  
| | 80      |  |           |  | 80    |  | 4,414 |  | (0       | )
| |         |  |           |  |       |  |       |  |          |  

|B. | Gross Field Reserves
      @ September 30, 2011
|-- | -----------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 197     |  |           |  | 197   |  | 67    |  |          |  |    
|Developed
      Non-Prod. |         | 
|Undeveloped               |         | 
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 197     |  |           |  | 197   |  | 67    |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    

|C. | YPF S.A. Working
      Interest Reserves @ September 30, 2011
|-- | -------------------------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 74      |  |           |  | 74    |  | 25    |  |          |  |    
|Developed
      Non-Prod. |         | 
|Undeveloped               |         | 
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 74      |  |           |  | 74    |  | 25    |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    

|D. | Notes:
|-- | ------

| |                       | 
| | --------------------- | 
| | GCA
        Engineer: | 
| |                       | 
| | Approved:             | 
| |                       | 
| | Date:                 | 
| |                       | 

Page 10


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UTE Magallanes

---

(Field /
  Area Name)

Crude
  Oil and Natural Gas Reserve Statement
  Reserves Certification @ September 30, 2011
  for YPF S.A.

|Basin:    |  | Austral            |  | YPF
        S.A. Oil Interest: |  | 50%
        / 100% | 
|--------- |  | ------------------ |  | ------------------------------ |  | ------------------ | 
|          |  |                    |  |                                |  |                    | 
|Province: |  | Santa
        Cruz |  | YPF
        S.A. Gas Interest: |  | 50%
        / 100% | 
|          |  |                    |  |                                |  |                    | 
|Country:  |  | Argentina          |  | Field
        Gas Usage:       |  | 4.85%              | 
|          |  |                    |  |                                |  |                    | 
|Operator  |  | Sipetrol           |  | Sales
        Gas:             |  | 95.15%             | 
|          |  |                    |  |                                |  |                    | 
|          |  |                    |  | Royalty:                       |  | 12.00%             | 
|          |  |                    |  |                                |  |                    | 

|A. | Cumulative Production
      to September 30, 2011
|-- | -------------------------------------------------

| | Oil     |  |           |  |       |  |       |  | Gas      | 
| | ------- |  | --------- |  | ----- |  | ----- |  | -------- | 
| | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline | 
| | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      | 
| | 7,503   |  |           |  | 7,503 |  |       |  |          | 
| |         |  |           |  |       |  |       |  |          | 

|B. | Gross Field Reserves
      @ September 30, 2011
|-- | -----------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 338     |  |           |  | 338   |  |       |  |          |  |    
|Developed
      Non-Prod. | 869     |  |           |  | 869   |  |       |  |          |  |    
|Undeveloped               |         | 
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 1,207   |  |           |  | 1,207 |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    

|C. | YPF S.A. Working
      Interest Reserves @ September 30, 2011
|-- | -------------------------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 184     |  |           |  | 184   |  |       |  |          |  |    
|Developed
      Non-Prod. | 489     |  |           |  | 489   |  |       |  |          |  |    
|Undeveloped               |         | 
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 672     |  |           |  | 672   |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    

|D. | Notes: | Working Interes
      is 50% up to concession end and 100% afterwards 
      See individual sub-units
|-- | ------ | -----------------------------------------------------------------------------------------------------

| |                       | 
| | --------------------- | 
| | GCA
        Engineer: | 
| |                       | 
| | Approved:             | 
| |                       | 
| | Date:                 | 
| |                       | 

Page 11


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UTE Palmar
  Largo

---

(Field /
  Area Name)

Crude
  Oil and Natural Gas Reserve Statement
  Reserves Certification @ September 30, 2011
  for YPF S.A

.


|Basin:    |  | Noroeste   |  | YPF
        S.A. Oil Interest: |  | 30.00%  | 
|--------- |  | ---------- |  | ------------------------------ |  | ------- | 
|          |  |            |  |                                |  |         | 
|Province: |  | Formosa    |  | YPF
        S.A. Gas Interest: |  | 30.00%  | 
|          |  |            |  |                                |  |         | 
|Country:  |  | Argentina  |  | Field
        Gas Usage:       |  | 100.00% | 
|          |  |            |  |                                |  |         | 
|Operator: |  | Pluspetrol |  | Sales
        Gas:            
|          |  |            |  |                                |  |         | 
|          |  |            |  | Royalty:                       |  | 12.00%  | 
|          |  |            |  |                                |  |         | 

|A. | Cumulative Production
      to September 30, 2011
|-- | -------------------------------------------------

| | Oil     |  |           |  |       |  |       |  | Gas      | 
| | ------- |  | --------- |  | ----- |  | ----- |  | -------- | 
| | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline | 
| | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      | 
| | 7,285   |  |           |  | 7,285 |  |       |  |          | 
| |         |  |           |  |       |  |       |  |          | 

|B. | Gross Field Reserves
      @ September 30, 2011
|-- | -----------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 309     |  |           |  | 309   |  |       |  |          |  |    
|Developed
      Non-Prod. |         | 
|Undeveloped               | 65      |  |           |  | 65    |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 374     |  |           |  | 374   |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    

|C. | YPF S.A. Working
      Interest Reserves @ September 30, 2011
|-- | -------------------------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 93      |  |           |  | 93    |  |       |  |          |  |    
|Developed
      Non-Prod. |         | 
|Undeveloped               | 20      |  |           |  | 20    |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 112     |  |           |  | 112   |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    

|D. | Notes:
|-- | ------

| |                       | 
| | --------------------- | 
| | GCA
        Engineer: | 
| |                       | 
| | Approved:             | 
| |                       | 
| | Date:                 | 
| |                       | 

Page 12


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UTE Puesto
  Hernández

---

(Field /
  Area Name)

Crude
  Oil and Natural Gas Reserve Statement
  Reserves Certification @ September 30, 2011 
  for YPF S.A

.


|Basin:    |  | Neuquina        |  | YPF
        S.A. Oil Interest: |  | 61.55% | 
|--------- |  | --------------- |  | ------------------------------ |  | ------ | 
|          |  |                 |  |                                |  |        | 
|Province: |  | Mendoza/Neuquén |  | YPF
        S.A. Gas Interest: |  | 61.55% | 
|          |  |                 |  |                                |  |        | 
|Country:  |  | Argentina       |  | Field
        Gas Usage:       |  |       
|          |  |                 |  |                                |  |        | 
|Operator  |  | Petrobras       |  | Sales
        Gas:             |  |       
|          |  |                 |  |                                |  |        | 
|          |  |                 |  | Royalty:                       |  | 15.00% | 
|          |  |                 |  |                                |  |        | 

|A. | Cumulative Production
      to September 30, 2011
|-- | -------------------------------------------------

| | Oil     |  |           |  |        |  |       |  | Gas      | 
| | ------- |  | --------- |  | ------ |  | ----- |  | -------- | 
| | Primary |  | Secondary |  | Total  |  | Cond. |  | Gasoline | 
| | Mm3     |  | Mm3       |  | Mm3    |  | Mm3   |  | Mm3      | 
| | 25,695  |  | 41,875    |  | 67,569 |  |       |  |          | 
| |         |  |           |  |        |  |       |  |          | 

|B. | Gross Field Reserves
      @ September 30, 2011
|-- | -----------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     |         |  | 2,753     |  | 2,753 |  |       |  |          |  |    
|Developed
      Non-Prod. |         | 
|Undeveloped               |         |  | 363       |  | 363   |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    |         |  | 3,116     |  | 3,116 |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    

|C. | YPF S.A. Working
      Interest Reserves @ September 30, 2011
|-- | -------------------------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     |         |  | 1,694     |  | 1,694 |  |       |  |          |  |    
|Developed
      Non-Prod. |         |  |           |  |       |  |       |  |          |  |    
|Undeveloped               |         |  | 223       |  | 223   |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    |         |  | 1,918     |  | 1,918 |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    

|D. | Notes:
|-- | ------

| |                       | 
| | --------------------- | 
| | GCA
        Engineer: | 
| |                       | 
| | Approved:             | 
| |                       | 
| | Date:                 | 
| |                       | 

Page 13


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UTE Puesto
  Hernández Extensión

---

(Field /
  Area Name)

Crude
  Oil and Natural Gas Reserve Statement
  Reserves Certification @ September 30, 2011 
  for YPF S.A.




|Basin:    |  | Neuquina        |  | YPF
        S.A. Oil Interest: |  | 100.00% | 
|--------- |  | --------------- |  | ------------------------------ |  | ------- | 
|          |  |                 |  |                                |  |         | 
|Province: |  | Mendoza/Neuquén |  | YPF
        S.A. Gas Interest: |  | 100.00% | 
|          |  |                 |  |                                |  |         | 
|Country:  |  | Argentina       |  | Field
        Gas Usage:       |  |        
|          |  |                 |  |                                |  |         | 
|Operator  |  | Petrobras       |  | Sales
        Gas:             |  |        
|          |  |                 |  |                                |  |         | 
|          |  |                 |  | Royalty:                       |  | 15.00%  | 
|          |  |                 |  |                                |  |         | 

|A. | Cumulative Production
      to September 30, 2011
|-- | -------------------------------------------------

| | Oil     |  |           |  |       |  |       |  | Gas      | 
| | ------- |  | --------- |  | ----- |  | ----- |  | -------- | 
| | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline | 
| | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      | 
| |         | 
| |         |  |           |  |       |  |       |  |          | 

|B. | Gross Field Reserves
      @ September 30, 2011
|-- | -----------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     |         |  | 2,366     |  | 2,366 |  |       |  |          |  |    
|Developed
      Non-Prod. |         | 
|Undeveloped               |         |  | 82        |  | 82    |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    |         |  | 2,448     |  | 2,448 |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    

|C. | YPF S.A. Working
      Interest Reserves @ September 30, 2011
|-- | -------------------------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     |         |  | 2,366     |  | 2,366 |  |       |  |          |  |    
|Developed
      Non-Prod. |         | 
|Undeveloped               |         |  | 82        |  | 82    |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    |         |  | 2,448     |  | 2,448 |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    

|D. | Notes:
|-- | ------

| |                       | 
| | --------------------- | 
| | GCA
        Engineer: | 
| |                       | 
| | Approved:             | 
| |                       | 
| | Date:                 | 
| |                       | 

Page 14


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UTE Ramos

---

(Field /
  Area Name)

Crude
  Oil and Natural Gas Reserve Statement
  Reserves Certification @ September 30, 2011 
  for YPF S.A.



|Basin:    |  | Noroeste   |  | YPF
        S.A. Oil Interest: |  | 50.70% | 
|--------- |  | ---------- |  | ------------------------------ |  | ------ | 
|          |  |            |  |                                |  |        | 
|Province: |  | Salta      |  | YPF
        S.A. Gas Interest: |  | 50.70% | 
|          |  |            |  |                                |  |        | 
|Country:  |  | Argentina  |  | Field
        Gas Usage:       |  | 3.52%  | 
|          |  |            |  |                                |  |        | 
|Operator  |  | Pluspetrol |  | Sales
        Gas:             |  | 96.48% | 
|          |  |            |  |                                |  |        | 
|          |  |            |  | Royalty:                       |  | 12.00% | 
|          |  |            |  |                                |  |        | 

|A. | Cumulative Production
      to September 30, 2011
|-- | -------------------------------------------------

| | Oil     |  |           |  |       |  |       |  | Gas      | 
| | ------- |  | --------- |  | ----- |  | ----- |  | -------- | 
| | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline | 
| | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      | 
| |         |  |           |  |       |  | 7,066 |  |          | 
| |         |  |           |  |       |  |       |  |          | 

|B. | Gross Field Reserves
      @ September 30, 2011
|-- | -----------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     |         |  |           |  |       |  | 300   |  |          |  | 533
|Developed
      Non-Prod. |         | 
|Undeveloped               |         |  |           |  |       |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    |         |  |           |  |       |  | 300   |  |          |  | 533
|                          |         |  |           |  |       |  |       |  |          |  |    

|C. | YPF S.A. Working
      Interest Reserves @ September 30, 2011
|-- | -------------------------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     |         |  |           |  |       |  | 152   |  |          |  | 270
|Developed
      Non-Prod. |         | 
|Undeveloped               |         |  |           |  |       |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    |         |  |           |  |       |  | 152   |  |          |  | 270
|                          |         |  |           |  |       |  |       |  |          |  |    

|D. | Notes:
|-- | ------

| |                       | 
| | --------------------- | 
| | GCA
        Engineer: | 
| |                       | 
| | Approved:             | 
| |                       | 
| | Date:                 | 
| |                       | 

Page 15


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    Cline & Associates


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UTE Río
  Negro Norte

---

(Field /
  Area Name)

Crude
  Oil and Natural Gas Reserve Statement
  Reserves Certification @ September 30, 2011
  for YPF S.A.



|Basin:    |  | Neuquina          |  | YPF
        S.A. Oil Interest: |  | 35.00% | 
|--------- |  | ----------------- |  | ------------------------------ |  | ------ | 
|          |  |                   |  |                                |  |        | 
|Province: |  | Río
        Negro |  | YPF
        S.A. Gas Interest: |  | 35.00% | 
|          |  |                   |  |                                |  |        | 
|Country:  |  | Argentina         |  | Field
        Gas Usage:       |  | 31.00% | 
|          |  |                   |  |                                |  |        | 
|Operator  |  | Pluspetrol        |  | Sales
        Gas:             |  | 69.00% | 
|          |  |                   |  |                                |  |        | 
|          |  |                   |  | Royalty:                       |  | 12.00% | 
|          |  |                   |  |                                |  |        | 

|A. | Cumulative Production
      to September 30, 2011
|-- | -------------------------------------------------

| | Oil     |  |           |  |       |  |       |  | Gas      | 
| | ------- |  | --------- |  | ----- |  | ----- |  | -------- | 
| | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline | 
| | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      | 
| | 2,520   |  |           |  | 2,520 |  | 6     |  |          | 
| |         |  |           |  |       |  |       |  |          | 

|B. | Gross Field Reserves
      @ September 30, 2011
|-- | -----------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 88      |  |           |  | 88    |  | 2     |  |          |  |    
|Developed
      Non-Prod. | 14      |  |           |  | 14    |  |       |  |          |  |    
|Undeveloped               |         | 
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 101     |  |           |  | 101   |  | 2     |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    

|C. | YPF S.A. Working
      Interest Reserves @ September 30, 2011
|-- | -------------------------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 31      |  |           |  | 31    |  | 1     |  |          |  |    
|Developed
      Non-Prod. | 5       |  |           |  | 5     |  |       |  |          |  |    
|Undeveloped               |         |  |           |  |       |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 36      |  |           |  | 36    |  | 1     |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    

|D. | Notes:
|-- | ------

| |                       | 
| | --------------------- | 
| | GCA
        Engineer: | 
| |                       | 
| | Approved:             | 
| |                       | 
| | Date:                 | 
| |                       | 

Page 16


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UTE San
  Roque

---

(Field /
  Area Name)

Crude
  Oil and Natural Gas Reserve Statement
  Reserves Certification @ September 30, 2011
  for YPF S.A.




|Basin:    |  | Neuquina  |  | YPF
        S.A. Oil Interest: |  | 34.11% | 
|--------- |  | --------- |  | ------------------------------ |  | ------ | 
|          |  |           |  |                                |  |        | 
|Province: |  | Neuquén   |  | YPF
        S.A. Gas Interest: |  | 34.11% | 
|          |  |           |  |                                |  |        | 
|Country:  |  | Argentina |  | Field
        Gas Usage:       |  | 1.72%  | 
|          |  |           |  |                                |  |        | 
|Operator  |  | Total     |  | Sales
        Gas:             |  | 98.28% | 
|          |  |           |  |                                |  |        | 
|          |  |           |  | Royalty:                       |  | 15.00% | 
|          |  |           |  |                                |  |        | 

|A. | Cumulative Production
      to September 30, 2011
|-- | -------------------------------------------------

| | Oil     |  |           |  |       |  |       |  | Gas      | 
| | ------- |  | --------- |  | ----- |  | ----- |  | -------- | 
| | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline | 
| | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      | 
| | 2,153   |  |           |  | 2,153 |  | 6,851 |  | 1,884    | 
| |         |  |           |  |       |  |       |  |          | 

|B. | Gross Field Reserves
      @ September 30, 2011
|-- | -----------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |      
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | -----
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG  
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3  
|Proved                    |         | 
|Developed
      Prod.     | 313     |  |           |  | 313   |  | 863   |  | 490      |  | 4,054
|Developed
      Non-Prod. |         | 
|Undeveloped               |         | 
|                          |         |  |           |  |       |  |       |  |          |  |      
|Sub-total
      Proved    | 313     |  |           |  | 313   |  | 863   |  | 490      |  | 4,054
|                          |         |  |           |  |       |  |       |  |          |  |      

|C. | YPF S.A. Working
      Interest Reserves @ September 30, 2011
|-- | -------------------------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |      
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | -----
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG  
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3  
|Proved                    |         | 
|Developed
      Prod.     | 107     |  |           |  | 107   |  | 294   |  | 167      |  | 1,383
|Developed
      Non-Prod. |         | 
|Undeveloped               |         | 
|                          |         |  |           |  |       |  |       |  |          |  |      
|Sub-total
      Proved    | 107     |  |           |  | 107   |  | 294   |  | 167      |  | 1,383
|                          |         |  |           |  |       |  |       |  |          |  |      

|D. | Notes:
|-- | ------

| |                       | 
| | --------------------- | 
| | GCA
        Engineer: | 
| |                       | 
| | Approved:             | 
| |                       | 
| | Date:                 | 
| |                       | 

Page 17 Gaffney,
    Cline & Associates


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UTE Tierra
  del Fuego

---

(Field /
  Area Name)

Crude
  Oil and Natural Gas Reserve Statement
  Reserves Certification @ September 30, 2011
  for YPF S.A.



|Basin:    |  | Neuquina                 |  | YPF
        S.A. Oil Interest: |  | 30.00% | 
|--------- |  | ------------------------ |  | ------------------------------ |  | ------ | 
|          |  |                          |  |                                |  |        | 
|Province: |  | Tierra
        del Fuego |  | YPF
        S.A. Gas Interest: |  | 30.00% | 
|          |  |                          |  |                                |  |        | 
|Country:  |  | Argentina                |  | Field
        Gas Usage:       |  | 7.98%  | 
|          |  |                          |  |                                |  |        | 
|Operator  |  | Total                    |  | Sales
        Gas:             |  | 92.02% | 
|          |  |                          |  |                                |  |        | 
|          |  |                          |  | Royalty:                       |  | 12.00% | 
|          |  |                          |  |                                |  |        | 

|A. | Cumulative Production
      to September 30, 2011
|-- | -------------------------------------------------

| | Oil     |  |           |  |        |  |       |  | Gas      | 
| | ------- |  | --------- |  | ------ |  | ----- |  | -------- | 
| | Primary |  | Secondary |  | Total  |  | Cond. |  | Gasoline | 
| | Mm3     |  | Mm3       |  | Mm3    |  | Mm3   |  | Mm3      | 
| | 13,018  |  | 4,253     |  | 17,270 |  | 4,460 |  | 999      | 
| |         |  |           |  |        |  |       |  |          | 

|B. | Gross Field Reserves
      @ September 30, 2011
|-- | -----------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 654     |  | 181       |  | 835   |  | 186   |  | 297      |  | 594
|Developed
      Non-Prod. |         | 
|Undeveloped               | 48      |  | 48        |  | 48    |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 702     |  | 181       |  | 883   |  | 186   |  | 297      |  | 594
|                          |         |  |           |  |       |  |       |  |          |  |    

|C. | YPF S.A. Working
      Interest Reserves @ September 30, 2011
|-- | -------------------------------------------------------------

|                          | Oil     |  |           |  |       |  |       |  | Gas      |  |    
|------------------------- | ------- |  | --------- |  | ----- |  | ----- |  | -------- |  | ---
|                          | Primary |  | Secondary |  | Total |  | Cond. |  | Gasoline |  | LPG
|                          | Mm3     |  | Mm3       |  | Mm3   |  | Mm3   |  | Mm3      |  | Mm3
|Proved                    |         | 
|Developed
      Prod.     | 196     |  | 54        |  | 251   |  | 56    |  | 89       |  | 178
|Developed
      Non-Prod. |         | 
|Undeveloped               | 14      |  |           |  | 14    |  |       |  |          |  |    
|                          |         |  |           |  |       |  |       |  |          |  |    
|Sub-total
      Proved    | 211     |  | 54        |  | 265   |  | 56    |  | 89       |  | 178
|                          |         |  |           |  |       |  |       |  |          |  |    

|D. | Notes:
|-- | ------

| |                       | 
| | --------------------- | 
| | GCA
        Engineer: | 
| |                       | 
| | Approved:             | 
| |                       | 
| | Date:                 | 
| |                       | 

Page 18


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| | Gaffney,
        Cline &
        Associates
| | -------------------------------------------









APPENDIX
  II
  AUDIT PROCESS DESCRIPTION



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|C1900.01/RW/CG/
      LT2071 
      YPF S.A. |  | Gaffney,
      Cline &
      Associates
|-------------------------------------------- |  | ---------------------------------------



DESCRIPTION
  OF THE AUDIT REVIEW

All of the YPF reserve
    statements were audited analyzing the basic information supplied, in the form
    of production databases on which decline curve analysis (DCA) could be applied
    to extrapolate the production of existing wells or elaborate type curves to
    estimate future production from proposed locations. The decline analysis includes
    a forecast of the water-oil ratio or oil cut projection to aid in controlling
    limits of the production forecasts.


Gas fields are better
    analyzed by extrapolation of the pressure behavior, so when data allowed,
    the reserves were estimated by material balance using updated static pressure
    data. Geological information in the form of structural and isopach maps, well
    logs, production tests, fluid laboratory tests and other pertinent information
    was used to assess both the reserve estimates and the classification/categorization
    of the proposed development program. What follows is a brief description of
    the methods used for reserve allocation in each of the audited areas.


Significant differences
    with YPF estimates were found in two areas: La Tapera-Puesto Quiroga and Río
    Negro Norte. These differences are included in the explanations.


|Acambuco
|--------

The Acambuco area is comprised
    of two major gas fields, Macueta and San Pedrito in the Noroeste basin. They
    are operated by Pan American under the UTE Acambuco concession through 2/16/2040
    and 10/26/2036 respectively. YPF owns a 22.5% working interest.


San Pedrito, with four
    wells produces some 2.5 MMm3/d gas. The main producing reservoirs
    are the Huamampampa, Icla and Santa Rosa formations of Devonian age. Proved
    Developed Producing reserves were estimated by decline analysis. Proved Undeveloped
    reserves were estimated for a late compression stage that would reduce the
    abandonment pressure. This estimation was performed through a nodal analysis
    that couples material balance with vertical and surface flow analysis.


In Macueta three wells
    produce from Icla and Huamampampa. The field is a continuation to the South
    of the San Alberto gas field in Bolivia. Here also Proved Developed Producing
    reserves were estimated by DCA. The development program includes drilling
    one additional well (#1004) and installing compression. The estimation of
    Proved Undeveloped reserves was done by nodal analysis and material balance,
    considering also the surface flow to the processing plant. The presence of
    water in the producers influences the expectations of recovery and the result
    of the pressure analysis was used to categorize the reserves.


Minor oil reserves exist
    in the area in Carboniferous formations. The San Pedro and Macueta Somero
    fields produce from one well each and have no further development plans. They
    volumes were estimated by DCA.


GCA found no material
    differences with the estimates presented by YPF in this area.




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|C1900.01/RW/CG/
      LT2071 
      YPF S.A. |  | Gaffney,
      Cline &
      Associates
|-------------------------------------------- |  | ---------------------------------------



|Aguada
      Pichana
|--------------------

Aguada Pichana is a major
    gas and condensate field located in the Neuquina basin producing from the
    Mulichinco formation. YPF holds a 27.27% working interest. The gas comes with
    varying proportions of CO2 and a processing plant extracts gasoline and NGL.


The Proved Developed Producing
    reserve was estimated by DCA. The field is divided in a main area called Aguada
    Pichana which is being developed toward the west (AP West, Cañadón
    de la Zorra and Las Cárceles) and a second area called Aguada Pichana
    North (APN) with extensions to the west (APN Phase 1 and Phase 2). Some of
    the recent development areas (AP West, CDZ and Las Cárceles) have been
    approved by the government as Gas Plus areas, allowing for a deregulated gas
    sales price for the wells in those areas.


Several wells were drilled
    and tested and are awaiting hook up. Their expected recovery has been categorized
    as Proved Developed Non Producing reserves. Future drilling locations were
    evaluated according to the behavior of existing production. One location in
    APN categorized as Proved Undeveloped was considered too far from production
    and eliminated from the reserve class entirely.


Although GCA found some
    differences in the classification and/or categorization of locations in the
    development program, the final difference in the aggregated reserve estimates
    was not significant.


|Aguaragüe
|---------

Aguaragüe is an area
    on the Noroeste basin producing gas, oil and condensate, operated by Tecpetrol
    through 11/14/2017. YPF holds a 30% working interest. There are three main
    gas fields, Aguaragüe (Santa Rosa-Icla formations), Chango Norte-La Porcelana
    (Huamampampa formation) and Campo Durán (Tupambi, San Telmo and Las Peñas
    formations), and five minor fields containing varying quantities of oil and
    gas.


The main gas fields identified
    above have Proved Developed Producing reserves estimated by DCA. Proved Undeveloped
    reserves were assigned to three drilling locations in Campo Durán Tupambi.
    The volumes were estimated through material balance that considered the past
    gas re-injection in the formation.


Of the minor fileds, Madrejones
    produces gas from Tupambi formation. Río Pescado, Lomitas Bloque Bajo,
    Tranquitas Somero and Altos de Yariguarenda are oil fields. Each only has
    Proved Developed Producing reserves, estimated by DCA and no additional development
    program.


GCA did not find significant
    differences with YPF estimates.




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|C1900.01/RW/CG/
      LT2071 
      YPF S.A. |  | Gaffney,
      Cline &
      Associates
|-------------------------------------------- |  | ---------------------------------------



|CNQ7A-
      CNQ7
|-----------------

CNQ7 and CNQ7A blocks
    extend across Mendoza and La Pampa provinces in the Neuquina basin and are
    composed of five fields: CNQ7, El Corcobo Norte, Jagüel Casa de Piedra,
    Cerro Huanul Sur all in Mendoza and Puesto Pinto in La Pampa. They are operated
    by Pluspetrol through 8/10/2029 in the case of CNQ7 (Mendoza) and 7/16/2033
    (Mendoza) and 9/11/2033 (La Pampa) respectively, in the case of CNQ7A. YPF
    participates with 30.01% working interest in CNQ7 and 50.0 % in CNQ7A.


The fields produce from
    the Centenario formation. CNQ7A block produces about 3.900 m3/d of oil from
    429 wells and injects 14,500 m3/d of water into 209 injectors. Most of the
    four fields are subjected to water injection. Proved Developed Producing reserves
    were extrapolated by DCA in both areas by using exponential decline trends
    by well.


As most of each field
    is subjected to water flooding, it is expected that as the oil production
    rate reduces with time, the future oil decline rate will also reduce, resulting
    in a higher recovery than evidenced in the previous PDP estimate. YPF conducted
    a secondary recovery estimation using the Sahara software, which enables estimating
    residual oil saturation per pattern and per layer. The resulting estimate
    of incremental volume is referred to as Pending Performance and categorized
    as Proved Undeveloped.


Proved Undeveloped reserves
    were also assigned to a drilling development program to complete marginal
    injection patterns. Estimates of reserves for these locations were performed
    through type wells with areas differentiated by net pay thickness and qualifying
    locations according to neighbor producers behavior.


.GCA did not find significant
    differences with YPF proved estimates in the CNQ7 nor in the CNQ7A block.


|El Tordillo
       La Tapera  Puesto Quiroga
|----------------------------------------------

El Tordillo and La Tapera
     Puesto Quiroga (LT-PQ) are neighboring blocks that produce oil and
    gas from the Bajo Barreal, Castillo and D129 formations of the San Jorge basin.
    They are operated by Tecpetrol under two different concessions through 11/14/2017
    and 7/29/2017 respectively. YPF participates with a 12.196% working interest.


Proved Developed Producing
    reserves were estimated by DCA by groups of wells. In El Tordillo, primary
    wells were grouped by vintage and secondary wells grouped by area. In LT-PQ
    all wells produce by primary depletion.


Proved Developed Non Producing
    reserves were assigned to a workover program to recover behind pipe oil scheduled
    in the period 2012-2015. Reserves were estimated through workover type wells
    differentiating primary (deep and shallow) and secondary wells.


In El Tordillo, GCA agreed
    with the categorization of 42 locations as Proved Undeveloped presented by
    YPF with deep objectives (Blocks C and G) and one location to shallow formations.
    Also GCA accepted the reserve estimates based on type wells and the behavior
    of neighboring producers. Most of the locations are infill or first step outs
    from producers. The development program spans the period 2012-2016.




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|C1900.01/RW/CG/
      LT2071 
      YPF S.A. |  | Gaffney,
      Cline &
      Associates
|-------------------------------------------- |  | ---------------------------------------

.

In LT-PQ YPF presented
    five Proved Undeveloped locations, GCA found that the Proved Undeveloped locations
    in Puesto Quiroga could not be located in the maps and therefore removed them
    from the total Proved Undeveloped. The reserves reduction caused by removing
    these locations resulted in a significant percentage difference between GCA
    and YPF in the LT-PQ block reserves. Although the difference in percentage
    is large, the amount of the reduction is small compared with other areas,
    such as El Tordillo.


|La Yesera
|---------

The La Yesera field produces
    volatile oil and solution gas from the Precuyano formation of the Neuquina
    Basin with three producing wells. Chevron operates the field since its discovery
    in 2001 though a concession contract that ends on 1/1/2030. YPF participates
    with 35% working interest.


Developed Producing reserves
    were estimated by DCA. As the fluid is highly under saturated, the Proved
    reserves were limited to the time at which the estimated field bubble point
    field pressure would be reached.


GCA agreed with the estimates
    and presents no significant difference with YPF.


|Lindero
      Atravesado
|------------------------

Lindero Atravesado is
    a primarily gas and condensate field discovered by Esso in 1961 and now operated
    by Pan American until 11/8/2026. YPF participates with 37.5 % working interest.
    The field produces gas and condensate from the Sierras Blancas formation and
    oil from the Lotena formation.


The area is divided in
    two main sub-areas, LA Oriental and LA Occidental. Proved Developed Producing
    reserves were estimated by DCA in each of the sub-areas.


GCA agreed with the YPF
    estimates.


|Magallanes
|----------

The Magallanes area produces
    gas and oil from the Springhill formation of the Austral Basin, offshore Argentina.
    It is operated by Sipetrol through 11/14/2017. YPF holds a 50.0 % working
    interest. The area has five platforms and was producing 850,000 m3/d gas and
    300 m3/d oil from 17 wells.


Gas reserves were estimated
    through material balance performed for each platform with a pressure and production
    data base measured from 1993 through 2008. The initial pressure of 167 Kg/cm2
    had declined to some 115 Kg/cm2 in 2008. At present rates, YPFs estimated
    abandonment pressure of 40 Kg/cm2 will not be reached by the time the concession
    expires. The estimated future production should be easily obtained from a
    pressure decline perspective. However from a productivity perspective, GCA
    noticed that production reduced significantly after 2008, when a fire in the
    main platform reduced the gas handling capacity of 2.4 million m3/d.




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|C1900.01/RW/CG/
      LT2071 
      YPF S.A. |  | Gaffney,
      Cline &
      Associates
|-------------------------------------------- |  | ---------------------------------------



YPF explained that recently
    the platform was repaired, and the production rate is increasing with expectation
    for full recovery of the capacity and hence of the production plateau.


At the effective date
    of the reserve estimates, September 30, 2011, the Proved Developed Producing
    reserves should be reduced, and the volumes related to the production capacity
    recovery should be categorized as Proved Developed Non Producing. While GCA
    estimated the split of the reserves between these categories, the total Proved
    Developed reserve coincides with the YPF estimate.


There is no other development
    activity planned in the area.


|Palmar
      Largo
|------------------

The Palmar Largo area
    encompasses ten oil fields of the Noroeste Basin with eight of them in the
    Formosa province and two, Balbuena Este and Tartagal Oeste, in the Salta province,
    all producing from the Yacoraite Cretaceous formation. Presently producing
    fields are the main Palmar Largo Estructura1 field, Ramón Lista, Balbuena
    Este, Cañada Rica, and El Potrillo fields. Puesto La Entrada, El Chorro,
    Tartagal Oeste, La Tigra Norte and El Molino are shut in and have no reserves.
    The area is operated by Pluspetrol through 11/15/2017 and YPF participates
    with a 30.0% working interest.


Proved Developed Producing
    reserves were estimated by DCA. Proved Undeveloped reserves were assigned
    to the infill drilling of a side track of well PL-10 in the main Estructura1
    field. The reserve volume was estimated by analogy with neighboring wells.


GCA agreed with the YPF
    estimated reserves.


|Puesto
      Hernandez
|----------------------

Puesto Hernández
    is a mature oil field discovered by YPF in November 1961, now operated by
    Petrobras. It extends across Neuquén and Mendoza provinces having different
    concessions through 11/14/2027 (Neuquén) and 11/14/2017 (Mendoza). YPF
    holds a 61.55% working interest through 2016 when the joint venture finalizes.
    After that date YPF will hold 100% participation up to the concession expiry.


The field produces 2,100m3/d
    oil through 742 production and 449 injection wells. It is under a major water
    injection program. The produced gas has high CO2 content and is injected in
    a neighboring field. The gas is not a reserve. Producing formations are Avilé,
    Agrio, Rayoso and La Tosca.


Proved Developed Producing
    reserves were estimated by DCA applied to group of wells distinguishing primary
    from secondary. Primary wells were grouped by vintage and wells with recent
    repairs have been grouped separately. Most of the extrapolations were performed
    with exponential trends, with exceptions in the Agrio and Rayoso formations
    where water injection is more intensive. In these cases plots of water-oil
    ratio versus cumulative oil production were used. The extrapolation was applied
    declining the total fluid production




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|C1900.01/RW/CG/
      LT2071 
      YPF S.A. |  | Gaffney,
      Cline &
      Associates
|-------------------------------------------- |  | ---------------------------------------



Proved Undeveloped reserve
    was assigned to a workover campaign that is being performed systematically
    as maintenance of the injection program. The estimate was based on workover
    type well and applied to a program of 75 interventions over the next two years.


GCA agreed with the estimates
    both for the joint venture period and for the balance of the exploitation
    concession.


|Ramos
|-----

The Ramos area produces
    gas and condensate from the Devonian Huamampampa, Icla and Santa Rosa formations.
    The field is operated by Pluspetrol and YPF participates with a direct 27.75%
    working interest and also with an indirect 22.95 % working interest through
    its share in Pluspetrol Energy. The concession contract expires on 1/22/2026.


The Ramos reservoirs extend
    to the South into the neighboring Aguaragüe area in the Chango Norte-La
    Porcelana field. Taking this into account, YPF analyzed a material balance
    by reservoir unifying all three fields. GCA observed that it is very likely
    that there was some misallocation of production from some commingled producing
    wells. Some Icla production seems to be wrongly attributed to Huamampampa.
    Also the split between concessions appears to be unbalanced due to reducing
    the Ramos contribution excessively. Therefore the results of the material
    balance analysis were taken only as indicative.


Proved Developed Producing
    reserves were estimated by DCA by well for each of the formations. GCA agreed
    with these estimates. There is no other source of reserves in Ramos.


|Río
      Negro Norte
|---------------------

The Río Negro Norte
    area produces from Precuyano, Lajas and Punta Rosada formations of the Neuquina
    Basin. Presently it has 29 producers and 15 water injection wells, producing
    144 m3/d of oil with 95% water cut. It is operated by Chevron through a concession
    contract that expires on 2/26/2024, and YPF participates with a 35.0% working
    interest. In the area there are ten different fields: Anticlinal de María,
    Anticlinal de María Occidental, Anticlinal Viejo, Cerro Solo, El Látigo,
    El Látigo Occidental, El Solitario Sur, Loma de María, Loma Negra
    and Loma Negra Precuyano.


Proved Developed Producing
    reserves were estimated by DCA by well, with exponential extrapolations. Proved
    Developed Non-Producing reserves were estimated for six shut in wells that
    are expected to be connected in 2011. The reserves of these wells were estimated
    as an extrapolation of their individual previous production history.


The economic limit test
    in Río Negro Norte for the Proved Developed case gave a limit in 2015.
    YPF stated its estimates prior to testing the economic limit, hence the difference
    between GCA and YPF is very noticeable. Therefore overall differences are
    the result of economic limit testing.




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|C1900.01/RW/CG/
      LT2071 
      YPF S.A. |  | Gaffney,
      Cline &
      Associates
|-------------------------------------------- |  | ---------------------------------------



|San
      Roque
|---------------

The San Roque block includes
    three fields: Aguada San Roque that produces gas and condensate, Loma las
    Yeguas producing oil, gas and condensate and Rincón Chico producing free
    gas. They are operated by Total through 11/14/2027 and YPF participates with
    a 34.11% working interest. The fields produce from volcanic intrusive into
    the source rock Quintuco-Vaca Muerta and also from clastic layers of the Mulichinco
    formation. Also some Centenario formation layers were found to be productive
    (Nivel A and Nivel C or Avilé).


Proved Developed Producing
    reserves were obtained by DCA by well for oil and gas products. Yields of
    plant products were estimated from recent historic values. GCA found that
    YPF did not include in its statement the oil Proved Developed Producing reserve
    of Loma las Yeguas. This omission accounts for the main difference, but when
    included in total equivalent barrels, it is a small portion of the San Roque
    Proved reserve.


There is no further source
    of reserve. The difference between GCA and YPF is small and positive.


|Tierra
      del Fuego
|----------------------

The Tierra del Fuego area
    is located in the Austral basin, Tierra del Fuego province and is operated
    by Petrolera Lago Fuego (subsidiary of Apache). YPF participates with a 30%
    working interest through a concession contract that expires on 11/14/2017.
    The fields in the area produce from the Springhill Upper Cretaceous formation.
    San Sebastián is a major gas field, and the other fields are Cañadón
    Piedras, Cabo Nombre, Bajo Grande, Sección Baños, and La Sara. Los
    Chorrillos is a separate unit that expires on 4/10/2016.


Proved Developed Producing
    reserves were estimated by DCA applied to group of wells or fields in the
    area. GCA agreed with the extrapolations.


There are several drilling
    and workover proposals that constitute an ongoing development plan. Proved
    Undeveloped reserves were assigned to two locations in Bajo Guadaloso field
    inside Chorrillos. Estimated volumes were obtained by type well obtained from
    the same field production history.


This program was reviewed
    and GCA obtained values very similar to YPF.




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| |  | Gaffney,
      Cline &
      Associates
| |  | ---------------------------------------







APPENDIX
  III
  STATEMENT OF QUALIFICATIONS



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|C1900.01/RW/CG/
      LT2071 
      YPF S.A. |  | Gaffney,
      Cline &
      Associates
|-------------------------------------------- |  | ---------------------------------------



|Statement
        of Qualifications 
        D. K. Morgan
|---------------------------------------------------------

D.K. Morgan is one of
    GCAs Senior Technical Managers and was responsible for overseeing the
    preparation of the audit. Mr. Morgan has over 43 years of diversified international
    industry experience mainly in reservoir-engineering, geology, reserves estimates,
    project development, economics and training in the assessment, classification
    and reporting of reserves and resources. Over the past 6 years he has been
    responsible for project review and oversight for GCAs Houston office
    as it including the reserves audits conducted on behalf of Repsol YPF S.A.
    and YPF S.A. He is a member of the Society of Petroleum Engineers (SPE) and
    holds a petroleum engineering degree from Marietta College.




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| |  | Gaffney,
      Cline &
      Associates
| |  | ---------------------------------------







APPENDIX
  IV
  SEC DEFINITIONS FOR OIL AND GAS RESERVES



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| |  | Gaffney,
      Cline &
      Associates
| |  | ---------------------------------------



UNITED
  STATES SECURITIES AND EXCHANGE COMMISSION (SEC)
  DEFINITIONS FOR OIL AND GAS RESERVES

|Proved
      Oil and Gas Reserves
|---------------------------------

Proved oil and gas reserves
    are the estimated quantities of crude oil, natural gas and natural gas liquids
    which geological and engineering data demonstrate with reasonable certainty
    to be recoverable in future years from known reservoirs under existing economic
    and operating conditions, i.e., prices and costs as of the date the estimate
    is made. Prices include consideration of changes in existing prices provided
    only by contractual arrangements, but not on escalations based upon future
    conditions.


|(i) | Reservoirs are considered
      proved if economic producibility is supported by either actual production
      or conclusive formation tests. The area of a reservoir considered proved
      includes (A) that portion delineated by drilling and defined by gas-oil
      and/or oil-water contacts, if any; and (B) the immediately adjoining portions
      not yet drilled, but which can be reasonably judged as economically productive
      on the basis of available geological and engineering data. In the absence
      of information on fluid contacts, the lowest known structural occurrence
      of hydrocarbons controls the lower proved limit of the reservoir.
|--- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

|(ii) | Reserves which can
      be produced economically through application of improved recovery techniques
      (such as fluid injection) are included in the "proved" classification when
      successful testing by a pilot project, or the operation of an installed
      program in the reservoir, provides support for the engineering analysis
      on which the project or program was based.
|---- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

|(iii) | Estimates of proved
      reserves do not include the following: (A) oil that may become available
      from know reservoirs, but is classified separately as "indicated additional
      reserves"; (B) crude oil, natural gas and natural gas liquids, the recovery
      of which is subject to reasonable doubt because of uncertainty as to geology,
      reservoir characteristics, or economic factors: (C) crude oil, natural gas,
      and natural gas liquids that may occur in undrilled prospects; and (D) crude
      oil, natural gas and natural gas liquids that may be recovered from oil
      shales, coal, gilsonite and other such sources.
|----- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

|Proved
      Developed Oil and Gas Reserves
|-------------------------------------------

Proved developed oil and
    gas reserves that can be expected to be recovered through existing wells with
    existing equipment and operating methods. Additional oil and gas expected
    to be obtained through the application of fluid injection or other improved
    recovery techniques for supplementing the natural forces and mechanisms of
    primary recovery should be included as "proved developed reserves" only after
    testing by a pilot project or after the operation of an installed program
    has confirmed through production response that increased recovery will be
    achieved.


|Proved
      Undeveloped Reserves
|---------------------------------

Proved undeveloped oil
    and gas reserves are reserves that are expected to be recovered from new wells
    on undrilled acreage, or from existing wells where a relatively major expenditure
    is required for recompletion. Reserves or undrilled acreage shall be limited
    to those drilling units offsetting productive units that are reasonably certain
    of production when drilled. Proved reserves for other undrilled units can
    be claimed only where it can be demonstrated with certainty that there is
    continuity of production from the existing productive formation. Under no
    circumstances should estimates for proved undeveloped reserves be attributable
    to any acreage for which an application of fluid injection or other improved
    recovery technique is contemplated, unless such techniques have been proved
    effective by actual tests in the area and in the same reservoir.




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