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PRESENTATION OF INFORMATION

In this annual report, we use the terms “we,” “us,” “our,” the “registrant” and the “Company” to refer to Pampa Energía S.A.

Financial Information  

This annual report contains our audited consolidated financial statements as of December 31, 2012, December 31, 2011 and 2010 January 1, 2011,and for the three years in the period ended December 31, 2011.2012 and 2011, and the notes thereto (the “Consolidated Financial Statements”).  The audited consolidated financial statementsConsolidated Financial Statements have been audited by Price Waterhouse & Co. S.R.L., member firm of PricewaterhouseCoopers network, whose report is included in this annual report.

Our audited financial statements have beenConsolidated Financial Statements are set forth in Item 18 beginning on page F-1 of this annual report. Our Consolidated Financial Statements are prepared in accordance with generally accepted accounting principles in Argentina (Argentine GAAP) and the regulations of the Comisión Nacional de Valores (National Securities Commission, or CNV), which differ in certain significant respects from generally accepted accounting principles in the United States of America (U.S. GAAP) and from International Financial Reporting Standards (IFRS).  Note 23 to our audited consolidated financial statements included elsewhere in this annual report provides a description(“IFRS”) as issued by the International Accounting Standards Board (the “IASB”) and have been approved by resolution of the significant differences between Argentine GAAP and U.S. GAAP, as they relate to us, and a reconciliation to U.S. GAAPBoard of net income and shareholders’ equity asDirectors’ meeting of December 31, 2011 and 2010 and for the fiscal years ended December 31, 2011, 2010 and 2009.Company held on March 8, 2013.

Significant Acquisitions

We started acquiring our principal generation, transmission, distribution and other core assets in 2006. Before these acquisitions, we did not have any operations or engage in any activities, as our former business activities, which were limited to the ownership and operation of a cold storage warehouse building, were suspended in 2003. Accordingly, prior to the second half of 2006, we have had no relevant operating history, comparable financial statements or business track record that might constitute a basis for comparing or evaluating the performance of our operations or business prospects following our recent acquisitions.   

Our significant acquisitions include Electricidad Argentina S.A. (“EASA”) in September 2007, which owns a controlling stake in our distribution subsidiary, Empresa Distribuidora y Comercializadora Norte S.A. (“Edenor”); Corporación Independiente de Energía S.A. (“CIE”) in August 2007 (now known as Inversora Piedra Buena S.A. or “IPB”), which owns our subsidiary Central Piedra Buena S.A. (“Piedra Buena”) generation facilities; the assets comprising Central Térmica Loma de la Lata S.A. (“Loma de la Lata” or “CTLL”) in May 2007; Pampa Inversiones S.A. (“PISA”) in January 2007; a direct interest in Central Térmica Güemes S.A. (“Güemes”); a direct interest in Inversora Nihuiles S.A. (“Nihuiles”) and Inversora Diamante S.A. (“Diamante”) in October 2006, which in turn own our two hydroelectric generation plants Hidroeléctrica Nihuiles (“HINISA”) and Hidroeléctrica Diamante (“HIDISA”),in February 2009 respectively, a direct interest in Petrolera Pampa S.A. (“Petrolera Pampa”), in February 2009; and a co-controlling interest in Compañía Inversora en Transmisión Eléctrica Citelec S.A. (“Citelec”) in September 2006, which owns a controlling stake in Compañía de Transporte de Energía Eléctrica en Alta Tensión S.A. (“Transener”).

Recent Developments

In JanuarySince 2011, the Company agreedEdenor has taken action to acquire fromdivest certain subsidiariesassets consisting of AEI, whether directly or through any of itsformer subsidiaries the following: (i) 77.2% of the outstanding capital stock of Empresa Distribuidora Eléctrica Regional S.A. (“EMDERSA”), a company engaged in the distribution of electricity in the Argentine provinces of San Luis, La Rioja and Salta, through itsand AESEBA S.A. (“AESEBA”).

Spin-off Process – EMDERSA

In order to carry out the sale of certain of EMDERSA’s former subsidiaries, Edenor, the controlling company of EMDERSA, was required to cause EMDERSA to complete a partial spin-off process (the “Spin-off Process”), which resulted in the creation of three new investment companies, (i) EDESAL Holding S.A. (“EDESALH”), holder of 99.99% of the capital stock and votes of Empresa Distribuidora San Luis S.A. (“EDESAL”), Empresa Distribuidora de Electricidad de La Rioja(ii) EDESA Holding S.A. (“EDELAR”EDESAH”), holder of 90% of the capital stock and votes of Empresa Distribuidora de Electricidad de Salta S.A. (“EDESA”), and (iii) EGSSA Holding (“EGSSAH”), holder of 99.99% of EGGSA’s capital stock and votes. EMDERSA was to retain 99.99% of the capital stock and voting rights in EDELAR. On December 16, 2011, at EMDERSA’s Extraordinary General Shareholders’ Meeting, which was resumed on January 13, 2012 after a recess, the generationSpin-off Process was approved.

The Spin-off Process has also been approved by theComisión Nacional de Valores (the National Securities Commission, or “CNV”) and registered with the Regulatory Agency of electricityCorporations (the “IGJ”), together with the registration of the three new companies. On November 8, 2012, the new companies were authorized by the National Securities Commission to go public, and they obtained admission to listing on theBolsa de Comercio de Buenos Aires (the Buenos Aires Stock Exchange).

Companies’ sale agreements

Edenor’s Board of Directors approved at different times the offer letters received for the carrying out of the following transactions:

·From Rovella Carranza S.A. (“Rovella”), for the acquisition of Edenor’s direct and indirect stake in EDESAL (the “EDESAL Sale”).

·From Salta Inversiones Eléctricas S.A. (“SIESA”), for the acquisition of Edenor’s direct and indirect stake in EDESA (the “EDESA Sale”)

·From the Company, for the acquisition of Edenor’s direct and indirect stake in EGSSA (the “EGSSA Acquisition”).

EDESAL Sale

On September 16, 2011, Edenor’s Board of Directors approved the offer for the acquisition of 78.44% of the capital stock and votes of EDESALH by Rovella for a total and final price of U.S.$ 26.7 million that was paid in two installments. The first of them, for U.S.$ 4.0 million, was paid three days after the acceptance of the offer, and the remaining balance was collected by Edenor on October 25, 2011.

Along with the payment of the balance in October 2011, EDESAL also repaid a financial loan granted by the Edenor to EDESAL for an amount of Ps. 37.5 million, plus interest accrued through the settlement date.

EDESA Sale

On April 23, 2012, Edenor’s Board of Directors accepted the offer made by Salta Inversiones Eléctricas S.A. (“SIESA”) to Edenor and its subsidiary Emdersa Generación SaltaEMDERSA Holding S.A. (“EGSSA”EMDERSAH”), for the acquisition of shares representing: (i) 78.44% of the capital stock and voting rights of EDESAH, holder of 90% of the capital stock and voting rights of EDESA, which in turn owns 99.99% of the capital stock and voting rights of Empresa de Sistemas Eléctricos Dispersos S.A. (ESED), and (ii) the remaining 0.01% of ESED.

The transaction was carried out on May 10, 2012 at the offered price payable through the delivery of Argentine sovereign debt bonds (Boden 2012) for a value equivalent to Ps. 100.5 million. Such price was partially cancelled through the payment of Ps. 83.8 million, and the remainder will be cancelled in five annual and consecutive installments in U.S. dollars, with the first of them falling due on May 5, 2013, at an interest rate of LIBOR plus a 2% margin.

As a part of this transaction, EDESA also cancelled in full a loan held with Edenor for an amount of Ps. 131.3 million plus accrued interest, and the purchaser released EMDERSA from any and all liability resulting from the surety granted by the latter to EDESA in connection with a syndicated loan held by that company with multiple banking entities.

As collateral for the payment of the price of the EDESA Sale, SIESA granted a second lien share pledge over 23.53% of the shares of EDESA in favor of Edenor.

EGSSA Acquisition

On October 3, 2011, the Company sent to Edenor an offer to buy 78.57% of the shares and votes of EGSSAH together with 0.01% of EGSSA’s capital stock held by Edenor. On October 11, 2011, Edenor’s Board of Directors approved such offer.

The total and final agreed-upon price for this transaction amounts to U.S.$ 10.8 million, to be paid in two installments. The first of them, for an amount of U.S.$ 2.2 million was made on October 31, 2011 as partial payment of the price, and the remaining balance will have to be paid in October 2013. The latter amount will accrue interest at an annual rate of 9.75%, payable semi-annually.

EDELAR Offer

An offer from Andes Energía Argentina S.A. (“Andes Energía”) was accepted by Edenor’s board of directors on September 16, 2011, pursuant to which a proposal was made for Andes Energía to acquire a purchase option for a price of U.S. $1.5 million to buy, if the Spin-off Process was completed within a term of two years, 78.44% of Edenor’s direct and indirect stake in EDELAR for U.S. $20.29 million, to be paid in two installments. The purchase option was paid for by the buyer on September 16, 2011. 

Subsequently, Edenor’s board of directors approved proposals from Andes Energía to extend the term during which the buyer could exercise the option, with Edenor retaining the right to freely sell or assign to any third party or cause the sale or assignment of some or all the shares that are the object of the transaction and/or the rights over such shares. In the event that a sale to a third party is made, Andes Energía option may not be exercised, there being no outstanding payment or any responsibility of any kind for Edenor or Andes Energía.

On December 31, 2012, the Andes Energía purchase option had expired. As of the date of this annual report, Edenor is currently negotiating with Andes Energía new terms and conditions. At the same time, Edenor has received other expressions of interests in connection with such assets from third parties, which are currently being analyzed, although no specific offers have yet been received.

Taking into consideration that Edenor still intends to sell these assets and that it has received other expressions of interests in connection therewith, such assets continue to be classified as assets available for sale.

AESEBA and EDEN Sale

On February 27, 2013, Edenor’s Board of Directors unanimously approved an offer sent by Servicios Eléctricos Norte BA S.L. (the “Buyer”) for (i) the acquisition of the shares representing 100% of the outstanding capital stock and voting rights of AESEBA, S.A. (“AESEBA”), an electric utility company, which owns 90% of the outstanding capital stock of Empresa Distribuidora de Energía Norte S.A. (“EDEN”), an electricity distribution company withholding the concession area in the north region of the Province of Buenos Aires. 

In connection with the acquisition of the CIESA Bonds and the other assets related to CIESA described above, on April 28, 2011, the Company and its subsidiaries Inversiones Argentina I, Pampa Inversiones S.A. and EPCA entered into an agreement (the “Acta Acuerdo”) with Petrobras Energía S.A., Petrobras Hispano S.A., and CIESA, pursuant to which the parties thereto agreed to (i) continue negotiating to reach an agreement to re-implement the restructuring of the CIESA Liabilities, (ii) cause CIESA to vote in favor of a dividend payment by TGS in an amount of approximately U.S.$ 239 million (the “TGS Dividend”), which was declared by the shareholders’ meeting of TGS on April 29, 2011 and (iii) to set up a trust (the “MSA Trust”) to hold CIESA’s pro rata portion of the TGS Dividend which, to the extent the restructuring of the CIESA Liabilities is completed, will be distributed as follows: (x) an amount equal to 4.3% of the TGS Dividend will be distributed to the Company (or its designee) and (y) the remainder, net of CIESA operating expenses for fiscal year 2011, will be distributed to the shareholders of CIESA following the restructuring of the CIESA Liabilities pro rata to their respective holding in CIESA. To the extent the restructuring of the CIESA Liabilities is not achieved as agreed by the parties to the Acta Acuerdo, the pro rata portion of the TGS Dividend held in trust shall be distributed to CIESA. 

On July 31, 2012, the ICSID Arbitration Court ordered, in accordance with the instructions timely given by the Company, the suspension of the arbitration proceeding brought by the Plaintiffs against the Republic of Argentina originally involving an amount in dispute which would currently amount to approximately U.S.$ 167 million.

Additionally,Such suspension was requested pursuant to the commitment undertaken with the Argentine Antitrust Commission and the ENERGAS by CIESA, EPCA, Petrobras and the Company on August 29, 2011, in the filings submitted before both entities seeking the approval of CIESA’s Restructuring Agreement. In this respect, the corresponding governmental approvals have not yet been granted as of the date of this annual report.

In connection with the above mentioned claims, on November 14, 2011, the board20, 2012, Ponderosa Assets Holding I LLC and Ponderosa Assets Holding II LLC (two new subsidiaries of directors of Ingentis S.A. decided to make a voluntary capital reduction over the capital stock of Ingentis S.A.Pampa Inversiones specially created for this transaction) entered into an assignment agreement with Enron Creditors Recovery Corp., Citicorp North America, Inc., Atlantic Commercial Finance, Inc., Enron Global Power & Pipelines L.L.C., and Citibank N.A., pursuant to which (i) Enron Creditors Recovery Corp. transferred all of its right, title and interest in and to the shares owned by Inversora Ingentis S.A. (Inversora Ingentis)general partnership interest in Ingentis S.A. were cancelled.  As consideration forPonderosa Assets LP to Ponderosa Assets Holding I LLC, and (ii) each of Citicorp North America, Inc., Atlantic Commercial Finance, Inc., Enron Global Power & Pipelines L.L.C. and any other relevant affiliate of Enron Creditors Recovery Corp. transferred all of its right, title and interest in and to the cancellationlimited partnership interests in Ponderosa Assets LP to Ponderosa Assets Holding II LLC; therefore, Ponderosa Assets Holding I LLC and Ponderosa Assets Holding II LLC became the owners of Ponderosa Assets LP, which is the shares, Ingentis S.A. paid Inversora Ingentisformal plaintiff under the amount of Ps.152,234,996, which was paid as follows: 1) by the assignment of a credit that Loma de la Lata held with Ingentis S.A. for an amount of Ps. 10,479,259; 2) the assignment of a credit with Güemes for an amount of Ps. 1,961,894; 3) the amount of Ps. 138,941,200 was offset in the terms of Section 818 and complementaries of theCódigo Civil de la República Argentina (Civil Code of Argentina) with an amount that Inversora Ingentis owed to Ingentis S.A. pursuant to certain loans granted by Ingentis S.A. to Inversora Ingentis; and 4) the amount of Ps. 852,643 was paid in cash.  This reduction of the capital stock of Ingentis S.A. was approved by the shareholders’ meeting held on December 2, 2011 and as a consequence, the current shareholders of Ingentis S.A. are Provincia del Chubut, an Argentine Province, and Petrominera Chubut Sociedad del Estado.ICSID Claim.

Furthermore, on December 30, 2011 the board directors of the Company, after entering into negotiations with Pampa Generación S.A., Inversora Ingentis S.A. and Powerco S.A. (“Powerco”) (in the case of Powerco the negotiations took place only in respect of the assets and liabilities related to its investment business) resolved that it would be beneficial for these companies if they were merged into a single company. The purpose of this mergemerger is to optimize the resources of each of the companies by simplifying and consolidating their administrative and operational structure. On March 9, 2012, and in connection with the required procedures, the Company'sCompany’s board of directors approved the special financial statements formergerfor merger purposes of the Company, the preliminary merger agreement executed betweenamong the Company, Pampa Generación S.A., Inversora Ingentis S.A. and Powerco, and the offering memorandum that describes the terms and conditions of the merger. On April 27, 2012, a shareholders meeting took place, where the merger as well as all of the documentation relating to it were approved. Finally, on July 13, 2012, the special financial statements for merger purposes were issued. On September 13, 2012, through Resolution No. 16,903, the CNV approved the corporate reorganization described above and referred the case to the IGJ for registration.  As of the date of this annual report, thesuch IGJ approval of the merger by the meeting of the shareholders of the Company is still pending.

Exchange Rate  

In this annual report, except as otherwise specified, references to “U.S. $” and “Dollars” are to U.S. Dollars, and references to “Ps.” and “Pesos” are to Argentine Pesos.  Solely for the convenience of the reader, we have converted certain amounts included in “Item 3.  Key Information” and elsewhere in this annual report from Pesos into U.S. Dollars using, for the information provided as of December 31, 2011,2012, the seller exchange rate reported by the Banco de la Nación Argentina, or Banco Nación, as of December 31, 20112012 of U.S. $1.00 = Ps. 4.304,4.9180, unless otherwise indicated.  These conversions should not be considered representations that any such amounts have been, could have been or could be converted into U.S. Dollars at that or at any other exchange rate.  The Federal Reserve Bank of New York does not report a noon buying rate for Pesos.  For more information regarding historical exchange rates, see “Item 3.  Key Information-Exchange Rates.”

The words “believe,” “may,” “will,” “aim,” “estimate,” “continue,” “anticipate,” “intend,” “expect” and similar words are intended to identify estimates and forward-looking statements.  Estimates and forward-looking statements speak only as of the date they were made, and we undertake no obligation to update or to renew any estimates and/or forward-looking statements because of new information, future events or other factors.  Estimates and forward-looking statements involve risks and uncertainties and are not guarantees of future performance.  Our future results may differ materially from those expressed in these estimates and forward-looking statements.  In light of the risks and uncertainties described above, the estimates and forward-looking statements discussed in this annual report might not occur and our future results and ourperformance may differ materially from those expressed in these forward-looking statements due to, inclusive,factors including, but not limited to, the factorsthose mentioned above.

PART I

Item 1.   Identity of Directors, Senior Management and Advisors

                        Not applicable.

Item 2.  Offer Statistics and Expected Timetable

                        Not applicable.

Item 3.           Key Information

Bolsa de Comercio de Buenos Aires (the Buenos Aires Stock Exchange).

SELECTED FINANCIAL DATACompanies’ sale agreements

This annual report contains our audited financial statements asEdenor’s Board of December 31,2011 and 2010 andDirectors approved at different times the offer letters received for the fiscalcarrying out of the following transactions:

·From Rovella Carranza S.A. (“Rovella”), for the acquisition of Edenor’s direct and indirect stake in EDESAL (the “EDESAL Sale”).

·From Salta Inversiones Eléctricas S.A. (“SIESA”), for the acquisition of Edenor’s direct and indirect stake in EDESA (the “EDESA Sale”)

·From the Company, for the acquisition of Edenor’s direct and indirect stake in EGSSA (the “EGSSA Acquisition”).

EDESAL Sale

On September 16, 2011, Edenor’s Board of Directors approved the offer for the acquisition of 78.44% of the capital stock and votes of EDESALH by Rovella for a total and final price of U.S.$ 26.7 million that was paid in two installments. The first of them, for U.S.$ 4.0 million, was paid three days after the acceptance of the offer, and the remaining balance was collected by Edenor on October 25, 2011.

Along with the payment of the balance in October 2011, EDESAL also repaid a financial loan granted by the Edenor to EDESAL for an amount of Ps. 37.5 million, plus interest accrued through the settlement date.

EDESA Sale

On April 23, 2012, Edenor’s Board of Directors accepted the offer made by Salta Inversiones Eléctricas S.A. (“SIESA”) to Edenor and its subsidiary EMDERSA Holding S.A. (“EMDERSAH”), for the acquisition of shares representing: (i) 78.44% of the capital stock and voting rights of EDESAH, holder of 90% of the capital stock and voting rights of EDESA, which in turn owns 99.99% of the capital stock and voting rights of Empresa de Sistemas Eléctricos Dispersos S.A. (ESED), and (ii) the remaining 0.01% of ESED.

The transaction was carried out on May 10, 2012 at the offered price payable through the delivery of Argentine sovereign debt bonds (Boden 2012) for a value equivalent to Ps. 100.5 million. Such price was partially cancelled through the payment of Ps. 83.8 million, and the remainder will be cancelled in five annual and consecutive installments in U.S. dollars, with the first of them falling due on May 5, 2013, at an interest rate of LIBOR plus a 2% margin.

As a part of this transaction, EDESA also cancelled in full a loan held with Edenor for an amount of Ps. 131.3 million plus accrued interest, and the purchaser released EMDERSA from any and all liability resulting from the surety granted by the latter to EDESA in connection with a syndicated loan held by that company with multiple banking entities.

As collateral for the payment of the price of the EDESA Sale, SIESA granted a second lien share pledge over 23.53% of the shares of EDESA in favor of Edenor.

EGSSA Acquisition

On October 3, 2011, the Company sent to Edenor an offer to buy 78.57% of the shares and votes of EGSSAH together with 0.01% of EGSSA’s capital stock held by Edenor. On October 11, 2011, Edenor’s Board of Directors approved such offer.

The total and final agreed-upon price for this transaction amounts to U.S.$ 10.8 million, to be paid in two installments. The first of them, for an amount of U.S.$ 2.2 million was made on October 31, 2011 as partial payment of the price, and the remaining balance will have to be paid in October 2013. The latter amount will accrue interest at an annual rate of 9.75%, payable semi-annually.

On December 31, 2011, 2010 and 2009.  See “Presentation2012, the Andes Energía purchase option had expired. As of Information—Financial Information.”  You should read the selected financial data in conjunction with our financial statements and related notes included elsewhere in this annual report.

The financial data asdate of December 31,2011 and 2010 and for the three years in the period ended December 31, 2011 are derived from our audited consolidated financial statements included elsewhere in this annual report, Edenor is currently negotiating with Andes Energía new terms and conditions. At the same time, Edenor has received other expressions of interests in connection with such assets from third parties, which are currently being analyzed, although no specific offers have yet been audited by Price Waterhouse & Co. S.R.L., member firmreceived.

Taking into consideration that Edenor still intends to sell these assets and that it has received other expressions of PricewaterhouseCoopers network. interests in connection therewith, such assets continue to be classified as assets available for sale.

AESEBA and EDEN Sale

On February 27, 2013, Edenor’s Board of Directors unanimously approved an offer sent by Servicios Eléctricos Norte BA S.L. (the “Buyer”) for (i) the acquisition of the shares representing 100% of the capital stock and voting rights of AESEBA, an electric utility company, which owns 90% of the outstanding capital stock of Empresa Distribuidora de Energía Norte S.A. (“EDEN”), an electricity distribution company holding the concession area in the north region of the Province of Buenos Aires; and (ii) the assignment of certain credits that EASA (the controlling company of Edenor) had with EDEN. The financial dataprice offered by the Buyer has been paid through the assignment to Edenor of certain rights under a trust established for purposes of the transaction to receive debt securities of Edenor, in an amount equivalent, as of December 31, 2008 and 2007 are derived from our audited consolidated financial statements that are not included in this annual report, which were audited by Price Waterhouse & Co. S.R.L., member firm of PricewaterhouseCoopers network, an independent registered public accounting firm.

Certain reclassifications have been made to our financial statements to present them in comparative form, to conform current year presentation; these reclassifications have no material impact on previously reported net income, net income per share, shareholders equity or cash flow. 

Our audited consolidated financial statements have been prepared in accordance with Argentine GAAP, which differs in certain significant respects from U.S. GAAP.  Note 23 to our audited consolidated financial statements included elsewhere in this annual report provides a descriptionthe date of the significant differences between Argentine GAAP and U.S. GAAP, as they relate to us, and a reconciliationacceptance of the offer, to U.S. GAAP of net (loss) income and shareholders’ equityfor the fiscal years ended December 31, 2011, 2010 and 2009 and$85 million face value, which are to be cancelled by Edenor as of December 31,2011 and 2010, respectively. 

In addition, Note 22such bonds are released to our audited consolidated financial statements included elsewhere in this annual report provides a description of the significant differences between Argentine GAAP and the IFRS as they relate to us, and a reconciliation to IFRS of shareholders’ equity at January 1, 2011 (date of transition to IFRS) and December 31, 2011 and a reconciliation of comprehensive income for the year ended December 31, 2011.

Our financial statements as of December 31, 2011, include the financial data of EMDERSA, AESEBA and Emdersa HOLDING.  The incorporation of AESEBA, including its subsidiary, Eden, was made on the basis of the general method of line item consolidation, which is established in Technical Resolution No. 21 issued by the FACPCE.  Furthermore, as of December 31, 2011,it in accordance with the decisionterms and conditions of Edenor’s Boardthe trust. As part of Directorsthe transaction, and in order to divestguarantee the obtention of funds necessary to acquire the Edenor bonds to be received by such company, U.S.$8.5 million of Argentine sovereign debt bonds multiplied by a certain factor was to be deposited into the trust on or before April 30, 2013.  As collateral for the portion of the price to be paid at that later date, the Buyer granted a pledge over 30% of the shares of AESEBA. On April 5, 2013 the transaction was settled in accordance with the terms described above.

Others

On January 27, 2011, we also acquired from AEI and sellthrough our subsidiary Pampa Inversiones S.A., all of the subsidiariesissued and outstanding capital stock of EMDERSA and Emdersa HOLDING, including EDESAL, EDELAR and EDESA (See “Presentation of Information – Recent developments”) we have classified these assetsInversiones Argentina I, a company incorporated in the consolidated financial statements asCayman Islands to which AEI had previously assigned all of December 31, 2011 as “Other assets available for sale”.  The corresponding resultsits right, title and interest to U.S.$ 199.6 million nominal value of the year 2011floating rate notes due April 22, 2002, issued by Compañía de Inversiones de Energía S.A. (“CIESA”) on April 22, 1997 (the “CIESA Bonds”), other liabilities of these subsidiariesCIESA arising from two derivatives transactions (together with the CIESA Bonds, the “CIESA Liabilities”) and the rights over certain lawsuits related to the CIESA Bonds. The CIESA Bonds have been included line by line in our consolidated statementsdefault since a missed principal repayment due on April 22, 2002. Pampa acquired the capital stock of operationsInversiones Argentina I for U.S.$ 136 million, while the year ended December 31, 2011.assets of such company, including the CIESA Bonds and accrued and unpaid interest, had a total value of approximately U.S.$ 322 million. CIESA is the controlling company of Transportadora de Gas del Sur (“TGS”). TGS is a leading gas transportation company in Argentina. TGS is also one of the leading natural gas liquid producers and traders, and an important provider of midstream services, including business structuring, turnkey construction and operation and maintenance of facilities used for gas storage, conditioning and transportation. On April 8, 2011, we acquired, directly and indirectly, 100% of the capital stock of Enron Pipeline Company Argentina S.A. (now known as EPCA S.A. or “EPCA”), which owns 10% of the capital stock of CIESA, which in turn owns 55.3% of the share capital of TGS, for a total price of U.S.$ 29.0 million.