Selected Unaudited Pro Forma Combined Financial Information;

Unaudited Pro Forma Combined Capitalization

The following selected unaudited pro forma combined financial information, which gives effect to the offers, is presented in U.S. dollars and reflects the combination of Alcan and Pechiney using the purchase method under U.S. GAAP. The pro forma adjustments are based upon available information and certain assumptions that Alcan believes are reasonable, including the assumptions that pursuant to the offers:

The selected unaudited pro forma combined financial information is presented for illustrative purposes only and is not necessarily indicative of the operating results or financial condition of the combined entities that would have been achieved had this offer and the French offer been completed during the periods presented, nor is the selected unaudited pro forma combined financial information necessarily indicative of the future operating results or financial position of the combined entities. The unaudited pro forma combined financial information does not reflect any cost savings or other synergies which may result from the combination. The unaudited pro forma financial information does not reflect any special items such as payments pursuant to change of control provisions or restructuring and integration costs which may be incurred as a result of the acquisition. In addition, the financial effects of any actions described in the section "The Offers - Reasons for the Offers - Employment Matters" of the prospectus dated October 24, 2003 (the "Prospectus"), which forms part of the registration statement on Form S-4 filed with the Securities and Exchange Commission by Alcan on October 24, 2003 (File No. 333-106851), such as costs of rationalization or synergies, cannot currently be determined and are therefore not reflected in the unaudited pro forma combined financial statements. Because Alcan has access only to publicly available financial information about Pechiney's accounting policies, there can be no assurance that the accounting policies of Pechiney conform to those of Alcan.

Regulatory clearances from the European Commission, the U.S. Department of Justice and the Swiss Competition Commission are subject to Alcan divesting certain businesses, operations or assets of Alcan and/or Pechiney and Alcan continuing to license certain technologies of Alcan and/or Pechiney to third parties. Because Alcan has not yet entered into any agreements with purchasers with respect to these divestitures, they have not been reflected in the unaudited pro forma combined financial statements. The businesses, operations or assets that Alcan is required to divest to comply with conditions imposed by regulatory authorities represent approximately 5% of total unaudited pro forma combined revenues. See "The Offers - Reasons for the Offers - Commitments Offered to the European Commission and the U.S. Department of Justice to Obtain Regulatory Approval" in the Prospectus.

This selected unaudited pro forma combined financial information has been derived from and should be read in conjunction with the attached "Pro Forma Combined Financial Statements of Alcan and Pechiney" and the related notes included herein, and with the respective consolidated financial information of Alcan and Pechiney as of and for the nine months ended September 30, 2003, and as of and for the year ended December 31, 2002, which are incorporated by reference in the Prospectus. All amounts are stated in U.S. dollars. This pro forma information is subject to risks and uncertainties, including those discussed in the Prospectus under "Risk Factors - Risks Relating to the Offers - We Have Not Been Given the Opportunity to Conduct a Due Diligence Review of the Non-Public Records of Pechiney. Therefore, We May Be Subject to Unknown Liabilities of Pechiney which May Have a Material Adverse Effect on Our Profitability And Results of Operations" and "Risk Factors - Risks Relating to the Offers - We Have Not Verified the Reliability of the Pechiney Information Included in, or Incorporated by Reference into, this Prospectus and, as a Result, Our Estimates of the Impact of Consummation of the Offers on the Pro Forma Information in this Prospectus May be Incorrect."

Alcan prepares its financial statements in accordance with Canadian GAAP, and provides a reconciliation of such financial statements to U.S. GAAP. Since Pechiney does not prepare Canadian GAAP financial information, but does prepare a U.S. GAAP reconciliation of its financial statements, the pro forma financial information herein is prepared in accordance with U.S. GAAP.

Unaudited Pro Forma Combined Financial Information

Unaudited Capitalization

-2-

Summary Selected Comparative Historical and Pro Forma Per Share Data

The following tables set forth certain historical per share data for Alcan and Pechiney as well as unaudited pro forma and equivalent pro forma combined per share data to reflect the combination of Alcan and Pechiney. The pro forma adjustments are based upon available information and certain assumptions that Alcan believes are reasonable, including the assumptions that pursuant to the offers:

The summary selected comparative historical and pro forma per share data is presented for illustrative purposes only and is not necessarily indicative of the operating results or financial condition of the combined entities that would have been achieved had this offer and the French offer been completed during the periods presented, nor is the summary selected comparative historical and pro forma per share data necessarily indicative of the future operating results or financial position of the combined entities.

This summary selected comparative historical and pro forma per share data has been derived from and should be read in conjunction with the attached "Pro Forma Combined Financial Statements of Alcan and Pechiney" and the related notes included herein, and with the respective consolidated financial information of Alcan and Pechiney as of and for the nine months ended September 30, 2003, and as of and for the year ended December 31, 2002, which are incorporated by reference in the Prospectus. All amounts are stated in U.S. dollars. This pro forma information is subject to risks and uncertainties, including those discussed in the Prospectus under "Risk Factors - Risks Relating to the Offers - We Have Not Been Given the Opportunity to Conduct a Due Diligence Review of the Non-Public Records of Pechiney. Therefore, We May Be Subject to Unknown Liabilities of Pechiney Which May Have a Material Adverse Effect on Our Profitability and Results of Operations" and "Risk Factors - Risks Relating to the Offers - We Have Not Verified the Reliability of the Pechiney Information Included in, or Incorporated by Reference into, this Prospectus and, as a Result, Our Estimates of the Impact of Consummation of the Offers on the Pro Forma Information in this Prospectus May be Incorrect."

-3-

-4-

The following unaudited pro forma combined balance sheet and unaudited pro forma combined statement of income, which give effect to the offers, are presented in U.S. dollars and reflect the combination of Alcan and Pechiney using the purchase method under U.S. GAAP. The pro forma adjustments are based upon available information and certain assumptions that pursuant to the offers:

The unaudited pro forma combined balance sheet and unaudited pro forma combined statement of income are presented for illustrative purposes only and are not necessarily indicative of the operating results or financial condition of the combined entities that would have been achieved had this offer and the French offer been completed during the periods presented, nor are the unaudited pro forma combined balance sheet and unaudited pro forma combined statement of income necessarily indicative of the future operating results or financial position of the combined entities. The unaudited pro forma combined balance sheet and unaudited pro forma combined statement of income do not reflect any cost savings or other synergies which may result from the combination. The unaudited pro forma financial information does not reflect any special items such as payments pursuant to change of control provisions or restructuring and integration costs which may be incurred as a result of the acquisition. In addition, the financial effects of any actions described in the section "The Offers - Reasons for the Offers - Employment Matters" of the Prospectus, such as costs of rationalization or synergies, cannot currently be determined and are therefore not reflected in the unaudited pro forma combined financial statements. Because Alcan has access only to publicly available financial information about Pechiney's accounting policies, there can be no assurance that the accounting policies of Pechiney conform to those of Alcan.

-5-

Alcan prepares its financial statements in accordance with Canadian GAAP, and provides a reconciliation of such financial statements to U.S. GAAP. Since Pechiney does not prepare Canadian GAAP financial information, but does prepare a U.S. GAAP reconciliation of its financial statements, the pro forma financial information herein is prepared in accordance with U.S. GAAP.

-6-

The accompanying notes are an integral part of the unaudited pro forma combined financial statements.

See Note 6 for sensitivity analyses.

-7-

-8-

-9-

These unaudited pro forma combined financial statements have been prepared to reflect the combination of Alcan and Pechiney using the purchase method.

Because Alcan has access only to publicly available financial information about Pechiney's accounting policies, there can be no assurance that the accounting policies of Pechiney conform to those of Alcan.

The unaudited pro forma combined financial statements are based on the following assumptions related to the combination:

As announced by Alcan on November 16, 2003, the Average Value (as defined in the Prospectus) of Alcan Common Shares is €34.7377 as determined in accordance with the terms of the offers. In addition, Alcan announced its decision to substitute an additional €4 in cash consideration for each Pechiney Common Share, each 10 Pechiney Bonus Allocation Rights or each 2 Pechiney ADSs tendered. This election results in 0.5441 Alcan Common Shares being offered for each Pechiney Common Share, each 10 Pechiney Bonus Allocation Rights or each 2 Pechiney ADSs tendered.

The combination will be accounted for as a "purchase" in accordance with U.S. GAAP with Alcan being identified as the acquirer.

The unaudited pro forma combined balance sheet is presented as if the combination between Alcan and Pechiney had been effective September 30, 2003 while the unaudited pro forma combined statements of income are presented as if the combination between Alcan and Pechiney had been effective January 1, 2002.

The purchase price will be allocated to the Pechiney assets acquired and liabilities assumed based on their estimated fair market value.

For the purpose of the unaudited pro forma combined financial statements, no purchase price allocation has been performed since Alcan has limited information about Pechiney.

-10-

The pro forma information is based on preliminary estimates and assumptions set forth below in note 5. These adjustments and allocation of purchase price are preliminary. Due to the limited financial and other information available to Alcan's management, the excess of the purchase price over the book value of the assets to be acquired has been allocated to "Excess of purchase price over book value of net assets acquired." The final purchase price allocation will be completed after asset and liability valuations are finalized by Alcan's management. A final determination of these fair values, which cannot be made prior to the completion of the combination, will include Alcan's management's consideration of all pertinent factors. This final valuation will be based on the actual net tangible and intangible assets of Pechiney that exist as of the date of the completion of the combination. Any final adjustments may change the allocation of purchase price which could affect the fair value assigned to the assets and liabilities and could result in material changes to the unaudited pro forma combined financial statements. Amount preliminarily allocated to "Excess of purchase price over book value of net assets acquired" will be allocated to various classes of assets, including intangible assets with indefinite lives, intangible assets with definite lives and goodwill. These final allocations may result in a material increase in amortization of assets. In addition, the impact of ongoing integration activities, the timing of the completion of the combination and other changes in Pechiney's net tangible and intangible assets prior to the completion of the combination could cause material differences in the information presented.

The accompanying unaudited pro forma combined financial statements are based on and should be read in conjunction with the historical consolidated financial statements of Alcan and Pechiney for the year ended December 31, 2002 and for the nine-month period ended September 30, 2003, including the notes thereto which are incorporated by reference in the Prospectus. Certain reclassifications have been made to the Pechiney historical financial statements to conform to the expected presentation to be used by Alcan upon completion of the combination and based on certain assumptions made by Alcan.

The pro forma adjustments are based upon available information and include certain assumptions and adjustments, which the management of Alcan believes to be reasonable. However, Alcan's adjustments and assumptions do not reflect any input from Pechiney, as discussed above. These adjustments are directly attributable to the combination and are expected to have a continuing impact on Alcan's business, results of operations and financial position. The pro forma information does not reflect cost savings expected to be realized from the elimination of certain expenses and from the synergies to be created and the costs to implement such cost savings or synergies. No assurance can be given that operating cost savings and synergies will be realized. The pro forma financial information does not reflect any special items such as payments pursuant to change of control provisions or restructuring and integration costs which may be incurred as a result of the acquisition.

-11-

To compute the pro forma $71 included in the purchase price relating to the assumed fair value of Alcan stock options issued to replace Pechiney stock options, Alcan used a Black-Scholes valuation model based on the weighted-average assumptions used to compute the pro forma compensation expense as reported in Alcan's historical consolidated financial statements. The principal assumptions used are: dividend yield of 1.65%; expected volatility of 35.73%; risk-free interest rate of 3.5% and expected life of 6 years. Alcan management has not yet determined how these options would be treated and, accordingly, the value and the accounting for any treatment of the Pechiney options may differ from those presented. Should all the holders of Pechiney options exercise their Pechiney options after the consummation of the offers, and Alcan exchange the resulting Pechiney Common Shares for Alcan Common Shares at an exchange ratio equivalent to that assumed in this pro forma financial information, unaudited pro forma combined Short-term borrowings would increase by $81, Common shareholders' equity would increase by $87 and Excess of purchase price over book value of net assets acquired would increase by $168. The impact on annual pro forma combined interest expense and pro forma combined income from continuing operations before nonrecurring charges and credits directly attributable to the acquisition would be less than $1 and the per share impact would be nil. See "The Offers - Treatment of Pechiney Stock Purchase Options and Pechiney Stock Subscription Options" in the Prospectus.

The unaudited pro forma combined financial statements are not necessarily indicative either of the results that actually would have been achieved if the transactions reflected therein had been effective during the periods presented or of the results which may be obtained in the future.

The Pechiney historical balance sheet information and related pro forma adjustments as of September 30, 2003 have been translated into U.S. dollars at the September 30, 2003 rate of exchange of $1.1650 for €1.00. The Pechiney historical statements of income information for the year ended December 31, 2002, the nine-month period ended September 30, 2003 and related pro forma adjustments to the unaudited pro forma statements of income have been translated at the average rates of exchange of $1.0577 for €1.00 and $1.1175 for €1.00, respectively.

Refer to Note 7 of the Alcan consolidated financial statements which are incorporated by reference into the Prospectus for a description of the differences between Canadian and U.S. GAAP as they apply to Alcan. However, investments in joint ventures have been accounted for using the equity method in these pro forma combined financial statements. In Alcan's consolidated financial statements incorporated by reference into the Prospectus, joint ventures are accounted for using the proportionate consolidation method.

Refer to Note 25 of the Pechiney financial statements which are incorporated by reference into this prospectus for a description of the differences between French and U.S. GAAP as they apply to Pechiney.

-12-

The unaudited pro forma combined financial statements incorporate the following adjustments:

The following adjustments have been made to prepare the pro forma balance sheet and statement of income. Pro forma statement of income adjustments are assumed to occur as of January 1, 2002. Pro forma balance sheet adjustments are assumed to occur at September 30, 2003.

The 1.6% assumed annual interest rate on debt issued to finance the acquisition and retirement of the Pechiney OCEANEs was determined based on the current 3-month LIBOR rate plus a margin of 0.5%, pursuant to the bridge credit facility that Alcan has entered into in connection with the transaction. See "The Offers - Source and Amount of Funds" in the Prospectus.

-13-

The unaudited pro forma combined financial statements are based upon the assumption that 100% of the Pechiney Common Shares (including Pechiney Common Shares underlying the Pechiney ADSs and excluding the Pechiney Common Shares held by Pechiney and one of its subsidiaries) are exchanged for Alcan Common Shares and cash in the offers. Should Alcan obtain only 94.9% of the Pechiney Common Shares, pro forma common shareholders' equity as of September 30, 2003 would decrease by $89 and Short-term borrowings would decrease by $176. Pro forma minority interest would increase by $162. Pro forma income from continuing operations before nonrecurring charges or credits directly attributable to the acquisition for the year ended December 31, 2002 would increase by $1 or $0.00 per common share, and for the nine-month period ended September 30, 2003 would increase by $3 or $0.01 per common share. For each further 10% decrease in the number of Pechiney Common Shares exchanged, pro forma common shareholders' equity as of September 30, 2003 would decrease by $164 and Short-term borrowings would decrease by $250 million. Pro forma minority interest would increase by $317. Pro forma income from continuing operations before nonrecurring charges or credits directly attributable to the acquisition for the year ended December 31, 2002, would increase by $1 or $0.00 per share, and for the nine-month period ended September 30, 2003 would increase by $5 or $0.02 per common share.

For every $100 of the "Excess of Purchase Price over book value of net assets acquired" which is allocated to tangible and identifiable assets with definite lives, pro forma combined annual income from continuing operations before nonrecurring charges or credits directly attributable to the acquisition would decrease by $3 or $0.01 per common share, assuming an amortization period of 20 years, estimated to be their average remaining useful life.

For each 12.5 basis points increase (decrease) in the interest rate on short-term borrowings assumed to finance the acquisition, pro forma combined annual income from continuing operations before nonrecurring charges or credits directly attributable to the acquisition would decrease (increase) by $2, or $0.01 per common share.

The unaudited pro forma combined financial statements are based upon the assumption that 100% of the Pechiney OCEANEs are exchanged in the offers. For every $100 million amount of Pechiney OCEANEs that are not exchanged, Pro forma combined income from continuing operations before nonrecurring charges or credits directly attributable to the acquisition would decrease by approximately $2 million, or $0.01 per common share, being the impact of the higher interest expense on the Pechiney OCEANEs compared to Alcan's incremental short term borrowing rate.

For each $1.00 change in the fair value per Alcan Common Share, the total purchase price, the excess of purchase price over book value of assets acquired, and common shareholders' equity would change by $42.60.

-14-