Material Event - Form 425

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Exhibit 99.1

UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL INFORMATION

Introduction

The following unaudited pro forma condensed combined financial information and notes thereto have been prepared in accordance with Article 11 of Regulation S-X in order to give effect to the mergers (defined below), the Discover Student Loan Sale (defined below), and the related transaction accounting adjustments (pro forma adjustments) described in the accompanying notes.

On February 19, 2024, Capital One Financial Corporation, a Delaware corporation ("Capital One" or "the Company"), entered into an agreement and plan of merger (the "merger agreement"), by and among Capital One, Discover Financial Services, a Delaware corporation ("Discover") and Vega Merger Sub, Inc., a Delaware corporation and a direct, wholly owned subsidiary of the Company ("Merger Sub"), pursuant to which (a) Merger Sub will merge with and into Discover, with Discover as the surviving entity in the merger (the "merger"); (b) immediately following the merger, Discover, as the surviving entity, will merge with and into Capital One, with Capital One as the surviving entity in the second-step merger (the "second step merger" and together with the merger, the "mergers"); and (c) immediately following the second step merger, Discover Bank ("Discover Bank"), a Delaware-chartered and wholly owned subsidiary of Discover, will merge with and into Capital One's wholly owned national bank subsidiary, Capital One National Association ("CONA"), with CONA as the surviving entity in the merger (the "CONA Bank Merger").

Subject to the terms and conditions of the merger agreement, at the effective time of the merger (the "effective time"), each share of common stock, par value $0.01 per share, of Discover ("Discover common stock") outstanding immediately prior to the effective time other than certain shares held by Capital One or Discover, will be converted into the right to receive 1.0192 shares (the "exchange ratio") of common stock, par value $0.01 per share, of Capital One ("Capital One common stock"). Holders of Discover common stock will receive cash in lieu of fractional shares.

Subject to the terms and conditions of the merger agreement, at the effective time of the second step merger (the "second effective time"), (i) each share of Fixed-to-Floating Rate Non-Cumulative Perpetual preferred stock, Series C, par value $0.01 per share, of Discover ("Discover Series C preferred stock") and (ii) each share of 6.125% Fixed-Rate Reset Non-Cumulative Perpetual preferred stock, Series D, par value $0.01 per share, of Discover ("Discover Series D preferred stock" and collectively with the Discover Series C preferred stock, the "Discover preferred stock"), outstanding immediately prior to the second effective time will be converted into the right to receive one share of an applicable newly created series of preferred stock of Capital One having terms that are not materially less favorable than the Discover Series C preferred stock or Discover Series D preferred stock, as applicable ("new Capital One preferred stock").

Subject to the terms and conditions of the merger agreement, at the effective time, (i) each outstanding Discover restricted stock unit award will be converted into a corresponding award with respect to Capital One common stock, with the number of shares underlying such award adjusted based on the Exchange Ratio, and (ii) each outstanding Discover performance stock unit award will be converted into a cash-based award, with the number of shares underlying such award determined based on the greater of target and actual performance for awards for which more than one year of the performance period has elapsed, and target performance for awards for which one year or less of the performance period has elapsed, with the per share cash amount determined using the product of the Exchange Ratio and the average of the closing sale prices of Capital One common stock for the five trading days ending on the day preceding the closing date of the mergers. Each such converted Capital One award will otherwise continue to be subject to the same terms and conditions as applied to the corresponding Discover equity award.

On July 17, 2024, Discover Bank entered into a purchase agreement with Santiago Holdings, LP ("Santiago Holdings"), an Ontario limited partnership and an affiliate of each of Carlyle and KKR, pursuant to which Discover

Bank agreed to sell its private student loan portfolio to Santiago Holdings (the "Discover Student Loan Sale"), with Firstmark Services, a division of Nelnet Inc. assuming responsibility for servicing the portfolio upon the sale. The cash purchase price payable to Discover Bank in the transaction is estimated to be up to approximately $10.8 billion which reflects the principal balance of the private student loan portfolio of approximately $10.1 billion as of June 30, 2024, and an additional premium, plus any outstanding accrued and unpaid interest at closing. The Discover Student Loan Sale is expected to be completed in multiple closings by the end of 2024, subject to waiver or satisfaction of customary closing conditions. The consummation of the mergers, the bank merger and the other transactions contemplated by the merger agreement are not conditioned on the consummation of the Discover Student Loan Sale.

The unaudited pro forma condensed combined statements of income for the three months ended March 31, 2024 and the year ended December 31, 2023 combines the historical results of Capital One and Discover, giving effect to the mergers (including the issuance of shares of Capital One common stock and new Capital One preferred stock in the mergers) and the Discover Student Loan Sale as if those transactions had occurred on January 1, 2023, the first day of Capital One's fiscal year 2023. The unaudited pro forma condensed combined balance sheet as of March 31, 2024 combines the historical consolidated balance sheets of Capital One and Discover as of March 31, 2024, giving effect to the mergers (including the issuance of shares of Capital One common stock and new Capital One preferred stock in the mergers) and the Discover Student Loan Sale as if those transactions had occurred on March 31, 2024.

The historical consolidated financial statements of Capital One and Discover have been adjusted in the accompanying unaudited pro forma condensed combined financial information to give effect to pro forma events that are necessary to account for the mergers (including the issuance of shares of Capital One common stock and new Capital One preferred stock in the mergers) and the Discover Student Loan Sale, in accordance with U.S. GAAP. Certain reclassifications have also been made to conform the historical financial statement presentation of Discover to that of Capital One. The unaudited pro forma adjustments are based upon available information and certain assumptions that Capital One believes are reasonable. The following unaudited pro forma condensed combined financial information does not reflect the costs of any integration activities or benefits that may result from the realization of future cost savings from operating efficiencies, or any other business changes or synergies that may result from the mergers or the Discover Student Loan Sale.

The following unaudited pro forma condensed combined financial information should be read in conjunction with:

Accounting for the Mergers

The mergers are being accounted for as a business combination using the acquisition method with Capital One as the accounting acquirer in accordance with Accounting Standards Codification ("ASC") Topic 805 ("ASC 805"), Business

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Combinations. Under this method of accounting, the aggregate purchase consideration will be allocated to Discover's assets acquired and liabilities assumed based upon their estimated fair values at the date of completion of the mergers. The process of valuing the net assets of Discover immediately prior to the mergers, as well as evaluating accounting policies for conformity, is preliminary. Any differences between the estimated fair value of the purchase consideration and the estimated fair value of the assets acquired and liabilities assumed will be recorded as goodwill. Accordingly, the purchase price allocation and related adjustments reflected in this unaudited pro forma condensed combined financial information are preliminary and subject to revision until a final determination of fair value of the assets acquired and liabilities assumed is performed. For more information, see "Note 1-Basis of Presentation".

Generally, and unless indicated otherwise, financial data included in the unaudited pro forma condensed combined financial information is presented in millions of U.S. Dollars and has been prepared on the basis of U.S. GAAP and Capital One's accounting policies.

The unaudited pro forma condensed combined financial information presented is for informational purposes only and is not necessarily indicative of the financial position or results of operations that would have been realized if the mergers (including the issuance of shares of Capital One common stock and new Capital One preferred stock in the mergers) and the Discover Student Loan Sale had been completed on the dates set forth above, nor is it indicative of the future results or financial position of Capital One following the mergers. The pro forma adjustments are preliminary and are subject to change as additional information becomes available and as additional analysis is performed. To the extent information was publicly available, such preliminary fair value estimates were corroborated against readily available information, inclusive of fair value marks disclosed on comparable portfolios of financial assets and liabilities. The preliminary pro forma adjustments have been made solely for the purpose of providing the unaudited pro forma condensed combined financial information.

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UNAUDITED PRO FORMA CONDENSED COMBINED BALANCE SHEET

As of March 31, 2024

($ in millions)

See the accompanying notes to the Unaudited Pro Forma Condensed Combined Financial Information

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UNAUDITED PRO FORMA CONDENSED COMBINED STATEMENT OF INCOME

For the Three Months Ended March 31, 2024

($ in millions, except share and per share data)

See the accompanying notes to the Unaudited Pro Forma Condensed Combined Financial Information.

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UNAUDITED PRO FORMA CONDENSED COMBINED STATEMENT OF INCOME

For the Year Ended December 31, 2023

($ in millions, except share and per share data)

See the accompanying notes to the Unaudited Pro Forma Condensed Combined Financial Information.

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NOTES TO THE UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL INFORMATION

Note 1 - Basis of Presentation

The unaudited pro forma condensed combined financial information and related notes are prepared in accordance with Article 11 of Regulation S-X.

As discussed in Note 2, certain reclassifications were made to align Discover's historical financial statement presentation with that of Capital One. Capital One is currently in the process of evaluating Discover's accounting policies with the information currently available and has determined that no significant adjustments are necessary to conform Discover's financial statements to the accounting policies used by Capital One. Therefore, the only changes noted herein are those related to presentation. As a result of this ongoing review and as more information becomes available, additional differences could be identified between the accounting policies of the two companies until finalized upon completion of the mergers.

The unaudited pro forma condensed combined financial information relating to the mergers was prepared using the acquisition method of accounting in accordance with ASC 805, with Capital One as the accounting acquirer, using the fair value concepts defined in ASC Topic 820, Fair Value Measurement, and based on the historical financial statements of Capital One and Discover. Under ASC 805, all assets acquired and liabilities assumed in a business combination are recognized and measured at their fair values as of the acquisition date, while transaction costs associated with the business combination are expensed as incurred. The excess of purchase consideration over the estimated fair value of assets acquired and liabilities assumed, if any, is allocated to goodwill. The unaudited pro forma condensed combined financial information also reflects the removal of the Discover student loans portfolio and related activity consistent with the terms of the Discover Student Loan Sale.

The allocation of the aggregate purchase consideration depends upon certain estimates and assumptions, all of which are preliminary. As of the date of this Current Report on Form 8-K, Capital One has not completed the valuation analysis and calculations in sufficient detail necessary to arrive at the required estimates of the fair market value of Discover's assets to be acquired or liabilities to be assumed, other than a preliminary estimate for intangible assets and certain financial assets and financial liabilities. Accordingly, apart from the aforementioned, certain Discover assets and liabilities are presented at their respective carrying amounts and should therefore be treated as preliminary. A final determination of the fair value of Discover's assets and liabilities will be based on Discover's actual assets and liabilities as of the closing date of the mergers and, therefore, cannot be made prior to the consummation of the mergers. The allocation of the aggregate purchase consideration has been made for the purpose of developing the unaudited pro forma condensed combined financial information. The final determination of fair values of assets acquired and liabilities assumed relating to the mergers could differ materially from the preliminary allocation of aggregate purchase consideration. The final valuation will be based on the actual net tangible and intangible assets of Discover existing at the acquisition date. As of the date of this Current Report on Form 8-K, Discover has not completed the Discover Student Loan Sale. As such, the sale consideration received for the Discover Student Loan Sale as well as any gain on sale is based on preliminary estimates and assumptions. The final sale consideration could differ materially from the preliminary sale consideration.

The unaudited pro forma condensed combined balance sheet, as of March 31, 2024, and the unaudited pro forma condensed combined statements of income for the three months ended March 31, 2024 and the year ended December 31, 2023, presented herein, are based on the historical financial statements of Capital One and Discover adjusted for the Discover Student Loan Sale. The unaudited pro forma condensed combined balance sheet as of March 31, 2024, is presented as if Capital One's acquisition of Discover and the Discover Student Loan Sale had occurred on March 31, 2024 and combines the historical balance sheet of Capital One as of March 31, 2024 with the historical balance sheet of Discover as of March 31, 2024, as adjusted for the Discover Student Loan Sale. The unaudited pro forma condensed combined statements of income for the three months ended March 31, 2024 and the year ended December 31, 2023 has been prepared as if the mergers and the Discover Student Loan Sale had occurred on January 1, 2023 and combines Capital One's historical statements of income for the three months ended March 31, 2024 and the year ended December 31, 2023 with Discover's historical statements of income for the three months ended March 31, 2024 and the year ended December 31, 2023, respectively, in each case as adjusted for the Discover Student Loan Sale.

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As noted previously, the unaudited pro forma condensed combined financial information does not reflect any anticipated synergies or dis-synergies, operating efficiencies or cost savings that may result from the mergers or the Discover Student Loan Sale or any acquisition and integration costs that may be incurred. The pro forma adjustments represent management's best estimates and are based upon currently available information and certain assumptions that Capital One believes are reasonable under the circumstances. There are no material transactions between Capital One and Discover during the period presented. Accordingly, no adjustments are necessary to eliminate any such transactions.

Note 2 - Conforming Accounting Policies and Reclassification Adjustments

During the preparation of this unaudited pro forma condensed combined financial information, Capital One performed a preliminary analysis of Discover's financial information to identify differences in accounting policies as compared to those of Capital One and differences in financial statement presentation as compared to the presentation of Capital One. With the information currently available, Capital One is not aware of any differences in accounting policies that would have a material impact on the unaudited pro forma condensed combined financial statements. However, certain reclassification adjustments have been made to conform Discover's historical financial statement presentation to Capital One's historical financial statement presentation. Following the completion of the mergers, or as more information becomes available, Capital One will finalize the review of accounting policies and reclassifications, which could be materially different from the amounts set forth in the unaudited pro forma condensed combined financial information presented herein.

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Note 3 - Preliminary Purchase Price Allocation

Estimated preliminary purchase consideration

The following table summarizes the determination of the preliminary estimated purchase consideration for Discover.