Fathom Digital Manufacturing : Fourth Quarter 2022 Presentation

Q4 and Full Year 2022 Financial Results

March 31, 2023

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Disclaimers

Forward-Looking Statements

Certain statements made in this presentation are "forward-looking statements" within the meaning of the "safe harbor" provisions of the United States Private Securities Litigation Reform Act of

1995. Words such as "estimates," "projects," "expects," "anticipates," "forecasts," "plans," "intends," "believes," "seeks," "may," "will," "would," "should," "future," "propose," "target," "goal," "objective," "outlook" and variations of these words or similar expressions (or the negative versions of such words or expressions) are intended to identify forward-looking statements. These forward-looking statements are not guarantees of future performance, conditions or results, and involve a number of known and unknown risks, uncertainties, assumptions and other important factors, many of which are outside the control of Fathom Digital Manufacturing Corporation ("Fathom") that could cause actual results or outcomes to differ materially from those discussed in the forward-looking statements. Important factors, among others, that may affect actual results or outcomes include: the inability to recognize the anticipated benefits of our business combination with Altimar Acquisition Corp. II; changes in general economic conditions, including as a result of the COVID-19 pandemic; the implementation of our optimization plan could result in greater costs and fewer benefits than we anticipate; the outcome of litigation related to or arising out of the business combination, or any adverse developments therein or delays or costs resulting therefrom; the ability to meet the New York Stock Exchange's listing standards following the consummation of the business combination; costs related to the business combination and

additional factors discussed in Fathom's Annual Report on Form 10-K for the fiscal year ended December 31, 2021, filed with the Securities and Exchange Commission (the "SEC") on April 8, 2022 as well as Fathom's other filings with the SEC.

If any of the risks described above materialize or our assumptions prove incorrect, actual results could differ materially from the results implied by our forward-looking statements. There may be additional risks that Fathom does not presently know or that Fathom currently believes are immaterial that could also cause actual results to differ from those contained in the forward- looking statements. In addition, forward-looking statements reflect Fathom's expectations, plans or forecasts of future events and views as of the date of this presentation. These forward- looking statements should not be relied upon as representing Fathom's assessments as of any date subsequent to the date of this presentation. Accordingly, undue reliance should not be placed upon the forward-looking statements. Fathom undertakes no obligation to update or revise any forward-looking statements made by management or on its behalf, including with respect to the financial guidance for first quarter of 2023 contained herein, whether as a result of future developments, subsequent events or circumstances or otherwise, except as required by law.

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Disclaimers

Non-GAAP Information

This presentation includes Adjusted Net Income, Adjusted EBITDA and Adjusted EBITDA margin, which are non-GAAP financial measures that we use to supplement our results presented in accordance with U.S. GAAP. We believe Adjusted Net Income, Adjusted EBITDA and Adjusted EBITDA margin are useful in evaluating our operating performance, as they are similar to measures reported by our public competitors and regularly used by security analysts, institutional investors and other interested parties in analyzing operating performance and prospects. Adjusted Net Income, Adjusted EBITDA and Adjusted EBITDA margin are not intended to be a substitute for any U.S. GAAP financial measure and, as calculated, may not be comparable to other similarly titled measures of performance of other companies in other industries or within the same industry. We define and calculate Adjusted Net Income as net income (loss) before the impact of any change in the estimated fair value of the company's warrant, earnout shares and tax receivable agreement liabilities, reorganization expenses, goodwill impairment, stock-based compensation, and certain other non-cash and non-core items, as described in the reconciliation included in the appendix to this presentation. We define and calculate Adjusted EBITDA as net income (loss) before the impact of interest income or expense, income tax expense and depreciation and amortization, and further adjusted for the following items: change in the estimated fair value of the company's warrant, earnout shares and tax receivable agreement liabilities, reorganization expenses, goodwill impairment, stock-based compensation, and certain other non-cash and non-core items, as described in the reconciliation included in the appendix to this presentation. Adjusted EBITDA excludes certain expenses that are required in accordance with U.S. GAAP because they are non-recurring (for example, in the case of reorganization expenses), non-cash (for example, in the case of depreciation, amortization, goodwill impairment, and stock-based compensation) or are not related to our underlying business performance (for example, in the case of interest income and expense). Adjusted EBITDA margin represents Adjusted EBITDA divided by total revenue. We include these non-GAAP financial measures because they are used by management to evaluate Fathom's core operating performance and trends and to make strategic decisions regarding the allocation of capital and new investments. Information reconciling forward-looking Adjusted EBITDA to GAAP financial measures is unavailable to Fathom without unreasonable effort. The company is not able to provide reconciliations of forward-looking Adjusted EBITDA to GAAP financial measures because certain items required for such reconciliations are outside of Fathom's control and/or cannot be reasonably predicted, such as the provision for income taxes. Preparation of such reconciliations would require a forward-looking balance sheet, statement of income and statement of cash flow, prepared in accordance with GAAP, and such forward-looking financial statements are unavailable to Fathom without unreasonable effort. Fathom provides a range for its Adjusted EBITDA forecast that it believes will be achieved, however it cannot accurately predict all the components of the Adjusted EBITDA calculation. Fathom provides an Adjusted EBITDA forecast because it believes that Adjusted EBITDA, when viewed with the company's results under GAAP, provides useful information for the reasons noted above. However, Adjusted EBITDA is not a measure of financial performance or liquidity under GAAP and, accordingly, should not be considered as an alternative to net income or cash flow from operating activities as an indicator of operating performance or liquidity.

Financial Disclosure Disclaimer

Fathom has not yet completed its reporting process for the three and twelve months ended December 31, 2022. The company expects to submit a notification of late filing on Form 12b-25 with the SEC on March 31, 2023. The preliminary unaudited results presented herein are based on Fathom's reasonable estimates and the information available at this time. The amounts reported herein are subject to various adjustments that are still under review and relate specifically to potential changes in the provision for income taxes. Such adjustments may be material and could impact the results reported herein.

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Q4 and Full Year 2022 Highlights

Fathom advanced key strategic initiatives during its first full year as a public company,

further solidifying its foundation to achieve profitable long-term growth

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Long-Term Growth Prospects Remain Intact

Accelerating manufacturing innovation for some of the most product-driven companies in the world by leveraging Fathom's comprehensive rapid prototyping and low-mid volume production capabilities

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