UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL INFORMATION

The following unaudited pro forma condensed combined financial information ("Unaudited Pro Forma Financial Information") has been prepared based on the historical audited consolidated financial statements of Sphere 3D Corp. ("Sphere") and Cathedra Bitcoin Inc. ("Cathedra"), as indicated below, and is intended to provide information about how the acquisition of Cathedra by Sphere in a stock-for-stock transaction (the "Arrangement") would have affected Sphere's historical financial statements. Capitalized terms used but not defined herein shall have the meanings ascribed to such terms in Sphere's Current Report on Form 8-K filed on June 3, 2026 (the "8-K").

The unaudited pro forma condensed combined balance sheet ("Unaudited Pro Forma Balance Sheet") as of March 31, 2026 gives effect to the Arrangement as if it occurred on March 31, 2026 and combines the historical balance sheets of Sphere and Cathedra as of such date. The unaudited pro forma condensed combined statement of operations ("Unaudited Pro Forma Statement of Operations") for the year ended December 31, 2025 and the three months ended March 31, 2026 combines the historical audited consolidated statement of operations of Sphere and the historical audited consolidated income statement of Cathedra for the year ended December 31, 2025, and the historical unaudited condensed consolidated statement of operations of Sphere and the historical unaudited condensed consolidated interim statement of Cathedra for the three months ended March 31, 2026, as if the Arrangement had occurred on January 1, 2025.

The Unaudited Pro Forma Financial Information has been prepared based on, and should be read in conjunction with:

• the historical audited consolidated financial statements of Sphere for the year ended December 31, 2025, included in Sphere's Annual Report on Form 10-K filed with the Securities and Exchange Commission (the "SEC") on March 27, 2026;

• the historical unaudited condensed consolidated financial statements of Sphere for the three months ended March 31, 2026, included in Sphere's quarterly report on Form 10-Q filed with the SEC on May 15, 2026;

• the historical audited consolidated financial statements of Cathedra for the year ended December 31, 2025, included in the 8-K;

• the historical unaudited consolidated financial statements of Cathedra for the three months ended March 31, 2026, included in the 8-K;

• the accompanying notes to the Unaudited Pro Forma Financial Information; and

• other information relating to Sphere and Cathedra contained in Sphere's Proxy Statement on Schedule 14A filed with the SEC on April 16, 2026 (the "Proxy Statement"). See the section titled "Additional Information" of the Proxy Statement.

The Unaudited Pro Forma Financial Information is presented for informational purposes only. The information has been prepared in accordance with Article 11 of Regulation S-X, as amended by Release No. 33-10786 "Amendments to Financial Disclosures about Acquired and Disposed Businesses," using the assumptions set forth in the notes to the Unaudited Pro Forma Financial Information. The Arrangement will be recorded as a business combination using the acquisition method of accounting under United States generally accepted accounting principles ("GAAP"). See section titled "The Arrangement—Accounting Treatment" of the Proxy Statement. Sphere, as the accounting acquirer, will record the acquired assets and assumed liabilities of Cathedra at their fair values as of the acquisition date. Sphere and Cathedra have determined a preliminary estimated purchase price calculated as described in Note 2 to the Unaudited Pro Forma Financial Information. The Unaudited Pro Forma Financial Information is not necessarily indicative of the financial position and results of operations that actually would have been achieved had the Arrangement occurred as of the dates indicated herein, nor do they purport to project the future financial position and operating results of the Combined Company. The Unaudited Pro Forma Financial Information also does not reflect the costs of any integration activities or cost savings or synergies expected to be achieved as a result of the Arrangement, which are described in the section titled "The Arrangement—Sphere's Reasons for the Arrangement" of the Proxy Statement, and, accordingly, does not attempt to predict or suggest future results.

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The Unaudited Pro Forma Financial Information is based on the assumptions and adjustments that are described in the accompanying notes. The Unaudited Pro Forma Financial Information and pro forma adjustments have been prepared based on preliminary estimates of fair value of acquired assets and liabilities assumed. Differences between these preliminary estimates and the final acquisition accounting are likely to occur and these differences could be material. The actual amounts recorded as of the completion of the Arrangement may also differ materially from the information presented in the Unaudited Pro Forma Financial Information as a result of, among other factors, the amount of cash used in operations between the signing of the Arrangement and the closing of the Arrangement, completion of the fair value analysis of the Sphere Series I Preferred Stock, acquired assets and liabilities assumed and other changes in Sphere's and Cathedra's assets and liabilities that occur prior to the completion of the Arrangement.

The Unaudited Pro Forma Financial Information does not give effect to the potential impact of current financial conditions, regulatory matters, operating efficiencies or other savings or expenses that may be associated with the integration of the two companies, if any.

The Transaction Accounting Adjustments represent management of Sphere's ("Sphere Management") best estimates and are based upon currently available information and certain assumptions that Sphere Management believes are reasonable and supportable. As the Unaudited Pro Forma Financial Information has been prepared based on these assumptions, the final amounts recorded may differ materially from the information presented herein.

Sphere has elected not to present Sphere Management's adjustments, which depict synergies and dis-synergies of the Arrangement, and will only be presenting transaction accounting adjustments in the Unaudited Pro Forma Financial Information. Therefore, the Unaudited Pro Forma Statement of Operations does not include the effects of the costs associated with any integration or restructuring activities resulting from the Arrangement, as they are nonrecurring in nature. In addition, the Unaudited Pro Forma Financial Information does not give effect to any anticipated synergies, operating efficiencies, tax savings, or cost savings that may be associated with the Arrangement.

Given Sphere's history of net losses and full valuation allowance on its net deferred tax assets, the pro forma adjustments to the Unaudited Pro Forma Statement of Operations resulted in no income tax adjustment to the pro forma financials.

Additionally, as discussed in Note 3, certain reclassifications were made to conform the historical presentation of Cathedra's consolidated financial statements to that of Sphere's financial statement presentation. The accounting policies used in the preparation of the Unaudited Pro Forma Financial Information are those set out in Sphere's audited financial statements for the year ended December 31, 2025. Sphere Management conducted a preliminary evaluation of accounting policies used by Cathedra compared to accounting policies used by Sphere and identified certain adjustments as described below. Following the completion of the Arrangement, Sphere will conduct a comprehensive review of Cathedra's accounting policies, and as a result of that review, Sphere may identify differences which may have a material impact on the Unaudited Pro Forma Financial Information.

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Sphere 3D Corp

UNAUDITED PRO FORMA CONDENSED COMBINED BALANCE SHEET

(in thousands)

As of March 31, 2026

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Sphere 3D Corp.

UNAUDITED CONDENSED COMBINED STATEMENT OF OPERATIONS

(in thousands, except share and per share data)

For the Three Months Ended March 31, 2026

Sphere 3D Corp.

UNAUDITED CONDENSED COMBINED STATEMENT OF OPERATIONS

(in thousands, except share and per share data)

For the Year Ended December 31, 2025

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SPHERE 3D CORP.

NOTES TO THE UNAUDITED PRO FORMA CONDENSED COMBINED FINANCIAL INFORMATION

(Expressed in U.S. Dollars)

1. BASIS OF PRESENTATION

After completion of the Arrangement, the consolidated financial statements of the consolidated entity will be prepared and presented in accordance with GAAP. The Unaudited Pro Forma Financial Information includes (all financial information is prepared in accordance with GAAP):

The Unaudited Pro Forma Financial Information should be read in conjunction with the historical consolidated financial statements and notes included therein of Sphere and Cathedra, as referred to above. Further review may identify differences between the accounting policies of Sphere and Cathedra that, when conformed, could have a material impact on the financial statements of Sphere, after the consummation of the Arrangement (the "Combined Company"). At this time, Sphere and Cathedra have made adjustments to align accounting policies and are not aware of any remaining accounting policy differences that would have a material impact on the Unaudited Pro Forma Financial Information of the Combined Company.

The Arrangement reflected in the Unaudited Pro Forma Financial Information has been prepared using the acquisition method of accounting in accordance with ASC 805, Business Combinations, under GAAP. Based on the definitions of control, Sphere is considered the legal and accounting acquirer. Under the acquisition method, the total estimated consideration is calculated as described in Note 2 to the Unaudited Pro Forma Financial Information. In accordance with the accounting guidance for business combinations, the assets acquired and liabilities assumed of Cathedra will be measured at their estimated fair values. The Unaudited Pro Forma Financial Information has accounted for Cathedra's assets and liabilities based on their historical amounts as no valuation has been completed at this time to determine their respective fair values.

It is Sphere Management's opinion that the Unaudited Pro Forma Financial Information includes all adjustments necessary for the fair presentation of the Arrangement described herein. The Unaudited Pro Forma Financial Information has been presented for informational purposes only and is not intended to reflect the results of operations or the financial position of Sphere which would have actually resulted had the Arrangement been effected on the dates indicated. Furthermore, the Unaudited Pro Forma Financial Information is not necessarily indicative of the results of operations that may be obtained in the future. Actual amounts recorded upon completion of the Arrangement will differ from those recorded in the Unaudited Pro Forma Financial Information and the differences may be material.

Certain amounts included herein have been subject to rounding adjustments. Accordingly, amounts shown as totals in certain tables may not be the arithmetic aggregation of the amounts that precede them.

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2. ACQUISITION OF CATHEDRA

Sphere Management has estimated the preliminary consideration and has not yet completed an external valuation analysis of the fair market value of Cathedra's assets to be acquired and liabilities to be assumed. As a result, Sphere Management has estimated the allocation of the preliminary purchase price to Cathedra's assets and liabilities. This preliminary purchase price allocation has been used to prepare the pro forma adjustments in the Unaudited Pro Forma Balance Sheet. The final purchase price allocation will be determined when the final purchase price has been determined, the final assets and liabilities and any asset sales are known, and detailed valuations and any other studies and calculations deemed necessary have been completed. The final purchase price and purchase price allocation could differ materially from the preliminary purchase price and purchase price allocation used to prepare the pro forma adjustments resulting from changes to assets and liabilities and to the ultimate purchase consideration, and operations during the intervening period to the closing of the Arrangement, among other factors.

Pursuant to the terms of the Arrangement Agreement, Sphere issued 2,405,300 Sphere Common Shares and 1,387,117 Sphere Series I Preferred Stock (the "Series I Shares") to the shareholders of Cathedra to acquire 100% of the issued and outstanding common shares of Cathedra as well as Replacement Warrants and share-based awards. This preliminary purchase price is based on the aggregate number of shares of Sphere Common Shares outstanding at the closing of the Arrangement using $1.90, the fair value of the Sphere Common Shares as of May 29, 2026, the last business day prior to the closing of the Arrangement on June 1, 2026. The fair value of the Series I Shares was estimated using a market approach to estimate the equity value of Sphere and further adjusted for lack of marketability. This is a preliminary estimate and the actual fair value may differ upon completion of the formal valuation analysis. A preliminary accounting assessment was performed over Sphere Series I Shares to determine the balance sheet classification. The preliminary conclusion resulted in permanent equity classification, which is subject to further accounting assessment and may be subject to change at the time the accounting assessment is completed.

The following table summarizes the preliminary estimated consideration:

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The adjustments reflect the acquisition method of accounting, which takes into account the total consideration transferred for Cathedra's assets and liabilities based on their historical amounts as no valuation has occurred at this time to determine their respective fair values.

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The financial information below illustrates the impact of adjustments made to Cathedra's consolidated financial statements as prepared in accordance with IFRS, in order to present them on a basis consistent with the Sphere's accounting presentation in accordance with GAAP.

As of March 31, 2026

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For the Three Months Ended March 31, 2026

For the Year Ended December 31, 2025

Adjustments herein represent the alignment of the accounting policies and reclassifications, including the following:

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A net loss cannot be diluted. When a company is in a net loss position, basic and diluted loss per share are the same.

The computation of pro forma diluted weighted-average shares outstanding excludes the following: