Use of Estimates

The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the consolidated financial statements, and the reported amounts of expenses during the reporting period. On an ongoing basis, the Company evaluates estimates and assumptions, including but not limited to those related to the fair value of the Convertible Loan, stock-based compensation expense, accruals for research and development costs, the valuation of deferred tax assets, impairment of goodwill and intangible assets and impairment of long-lived assets. Management bases its estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ materially from those estimates.

Cash and Cash Equivalents

Cash and cash equivalents consist primarily of cash deposits and marketable securities with original maturities of less than three months.

Fair Value of Financial Instruments

Financial instruments include cash equivalents, prepaid expenses and other receivables, restricted cash, accounts payable and accrued liabilities, accrued compensation and other current liabilities, Convertible Loan and long-term debt. The carrying amounts of the above assets and liabilities are generally considered to be representative of their respective fair values because of the short-term nature of those instruments. The Convertible Loan is accounted for at fair value at each period end. Long-term debt was accounted at fair value at inception and its subsequent fair value is not significantly different from its amortized basis, as effective interest rate is considered at market.

Impairment of Long-Lived Assets

The Company reviews long-lived assets for impairment when events or changes in circumstances indicate the carrying value of the assets may not be recoverable. Recoverability is measured by comparison of the carrying values of the assets to future net undiscounted cash flows that the assets or the asset groups are expected to generate. An impairment loss is recognized when estimated future undiscounted cash flows expected to result from the use of the asset and its eventual disposition are less than the carrying amount of the asset. During the year ended December 31, 2025, the Company recorded an impairment expense related to certain operating lease ROU assets. Refer to Note 12, Commitments and Contingencies, for further details about the impairment charge. No impairment losses on long-lived assets were recorded for the year ended December 31, 2024.

Goodwill

Goodwill, which has an indefinite useful life, represents the excess of purchase consideration over the fair value of net assets acquired in an acquisition. Goodwill is not subject to amortization and is required to be tested for impairment at least on an annual basis. The Company tests goodwill for impairment as of December 31 of each year. The Company determines whether goodwill may be impaired by comparing the carrying value of the single reporting unit, including goodwill, to the fair value of the reporting unit. If the fair value is less than the carrying amount, a more detailed analysis is performed to determine whether goodwill is impaired. The impairment loss, if any, is measured as the excess of the carrying value of the goodwill over the implied fair value of the goodwill and is recorded in the Company’s consolidated statements of operations. The Company performed quantitative analysis of goodwill impairment and noted no impairment as of December 31, 2025 and 2024.

Stock-Based Compensation

Compensation expense related to stock options granted to employees and non-employees is measured at the grant date based on the estimated fair value of the award and is recognized on the accelerated attribution method over the requisite service period. To estimate the fair value of an award, the Company uses the Black-Scholes option pricing model. This model requires inputs such as expected term, expected volatility, expected dividend yield of stock and risk-free interest rate. Expected volatility is based on the historical volatility of the Company’s own stock price as well as stock volatility of similar publicly traded peer companies. The expected term represents the period that the Company expects its stock options to be outstanding. The expected term assumption is estimated using the simplified method set forth in the U.S. Securities and Exchange Commission Staff Accounting Bulletin 110, which is the mid-point between the option vesting date and the expiration date. The risk-free rate is based on the U.S. Treasury yield curve in effect at the time of grant commensurate with the expected term assumption. The fair value of restricted stock units (“RSUs”) and restricted stock awards (“RSAs”) is determined based on the number of units granted and the closing price of the Company’s Common Stock as of the grant date. The Company accounts for forfeitures in the period they occur. Stock-based compensation expense for an award with a performance condition is recognized when the achievement of such performance condition is determined to be probable. If the outcome of such performance condition is not determined to be probable or is not met, no compensation expense is recognized and any previously recognized compensation expense is reversed.

Grants Revenue and Other Awards

The Company determines whether agreements are within the scope of ASC Topic 606, Revenue from contracts with customers (“ASC 606”) or other topics at the effective date of an agreement.

The Company also determines if grants and awards are in scope of ASC Topic 808, Collaborative Arrangements (“ASC 808”). To the extent the grant or award is within the scope of ASC 808, the Company recognizes the award upon achievement of certain milestones as credits to research and development expenses. For grant and awards outside the scope of ASC 808, the Company applies ASC 606 or International Accounting Standards No. 20, Accounting for Government Grants and Disclosure of Government Assistance, by analogy, and revenue is recognized when the Company incurs expenses related to the grant for the amount the Company is entitled to under the provisions of the agreement.

The Company also considers the guidance in ASC Topic 730, Research and Development (“ASC 730”), which requires an assessment, at the inception of the grant or award, of whether the agreement is a liability. If Armata is obligated to repay funds received regardless of the outcome of the related research and development activities, then the Company is required to estimate and recognize that liability. Alternatively, if the Company is not required to repay the funds, then payments received are recorded as revenue or contra-expense as the expenses are incurred.

As of December 31, 2025 and 2024, the Company recognized as other receivables in its consolidated balance sheets $0.5 million and $0.7 million, respectively, related to invoiced grant amounts that have not been received.

Income Taxes

The Company utilizes the asset and liability method of accounting for income taxes. Deferred income taxes are recognized for the future tax consequences of temporary differences using enacted statutory tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. Temporary differences include the differences between the financial statement carrying amounts and the tax basis of existing assets and liabilities and net operating loss and tax credit carryforwards. The effect on deferred taxes of a change in tax rates is recognized in income (expense) in the period that includes the enactment date. The Company evaluates the likelihood that deferred tax assets will be recovered from future taxable income. Valuation allowances are provided if, based upon the weight of available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized.

The Company’s income tax returns are based on calculations and assumptions that are subject to examination by the Internal Revenue Service and other tax authorities. In addition, the calculation of tax liabilities involves dealing with uncertainties in the application of complex tax regulations. The Company recognizes liabilities for uncertain tax positions based on a two-step process. The first step is to evaluate the tax position for recognition by determining if the weight of available evidence indicates that it is more likely than not that the position will be sustained on audit, including resolution of related appeals or litigation processes, if any. The second step is to measure the tax benefit as the largest amount that is more than 50% likely of being realized upon settlement.

Basic and Diluted Net Loss per Share

Basic net loss per common share is calculated by dividing the net loss attributable to common stockholders by the weighted-average number of Common Stock outstanding during the period, without consideration of potentially dilutive securities. Diluted net loss per share is computed by dividing the net loss attributable to common stockholders by the weighted-average number of Common Stock and potentially dilutive securities outstanding for the period. For purposes of the diluted net loss per share calculation, the Common Stock warrants, Convertible Loan, unvested restricted stock awards and restricted stock units, and stock options are considered to be potentially dilutive securities. Basic and diluted net loss attributable to common stockholders per share is presented in conformity with the two-class method required for participating securities. Under the two-class method, warrants issued to Innoviva SO are assumed to participate in undistributed earnings on an as-exercised basis, in accordance with the warrant agreements. The Company’s participating securities do not have a contractual obligation to share in the Company’s losses. As such, the net loss was attributed entirely to common stockholders.