Lantheus Holdings, Inc.

1. Description of Business

The Company develops, manufactures and commercializes innovative diagnostic and therapeutic products that assist clinicians in the diagnosis and treatment of cancer, heart disease and other diseases.

The Company’s commercial products are used by cardiologists, internal medicine physicians, neurologists, nuclear medicine physicians, oncologists, radiologists, sonographers, technologists, and urologists working in a variety of clinical settings. The Company believes that its diagnostic products provide information that enables healthcare providers to better detect and characterize, or rule out, disease, with the potential to achieve better patient outcomes, reduce patient risk, and limit overall costs.

The Company produces and markets its products throughout the United States (the “United States” or the “U.S.”), selling primarily to hospitals, independent imaging centers and government facilities. The Company sells its products outside the United States through a combination of direct distribution in Canada, third-party distribution relationships in Europe, Canada, Australia, Asia-Pacific, Central America and South America and by licensing exclusive rights to develop and commercialize certain products outside the United States.

Sales of PYLARIFY are generated in the United States through an internal PYLARIFY sales team, as well as a sales team at some of the Company’s positron emission tomography (“PET”) manufacturing facilities (“PMF”) partners. Sales of DEFINITY are generated in the United States through an internal DEFINITY sales team. Sales of Neuraceq are generated in the United States through an internal Neuraceq sales team and in European markets through third-party distributors. Research revenue is derived from existing partnerships with pharmaceutical companies and academic institutions that use our products and product candidates in clinical trials and includes milestone and dose-related payments. A small portion of the Company’s nuclear imaging product sales in the United States are generated through the Company’s internal sales force to hospitals and clinics that maintain their own in-house radiopharmaceutical preparation capabilities.

In Europe, Australia, Asia-Pacific, Central America and South America, the Company generally relies on third-party distributors to market, sell and distribute its nuclear imaging and ultrasound enhancing agent products, either on a country-by-country basis or on a multi-country regional basis. The Company is headquartered in Massachusetts, with offices in New Jersey, Canada, Germany, Switzerland, Sweden and the United Kingdom.

2. Summary of Significant Accounting Policies

Basis of Presentation and Principles of Consolidation

The accompanying consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States (“U.S. GAAP”). The consolidated financial statements include the accounts of the Company and its direct and indirect wholly-owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation.

Use of Estimates

The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the consolidated financial statements, and the reported amounts of revenues and expenses during the reporting period. The estimates reflected in the Company’s consolidated financial statements include, but are not limited to, certain judgments regarding revenue recognition, goodwill, tangible and intangible asset valuation and estimated useful lives, inventory valuation, asset retirement obligations, contingent assets and liabilities, income tax liabilities and related indemnification receivable, deferred tax assets and liabilities and accrued expenses. Actual results could materially differ from those estimates or assumptions.

Revenue Recognition

The Company recognizes revenue when it transfers control of promised goods or services to its customers in an amount that reflects the consideration to which the Company expects to be entitled to in exchange for those goods and services. See Note 3, “Revenue from Contracts with Customers,” to these consolidated financial statements, for further discussion on revenues.

Accounts Receivable, Net

Accounts receivable have been reduced by an allowance for credit losses. The allowance for credit losses represents the Company’s best estimate of the amount of probable credit losses in our accounts receivable. The Company’s allowance is based on a number of factors, including an evaluation of customer credit worthiness, the age of the outstanding receivable, economic trends, historical experience and other information over the payment periods. The Company reviews and adjusts the allowance for expected credit losses on a quarterly basis. Accounts receivable balances are written off against the allowance for expected credit losses when the Company determines that the balances are not recoverable. Allowance for credit losses was $9.5 million and $7.8 million at December 31,2025 and 2024, respectively.

Income Taxes

The Company accounts for income taxes using an asset and liability approach. Income tax expense represents income taxes paid or payable for the current year plus the change in deferred taxes during the year. Deferred taxes result from differences between the financial and tax bases of the Company’s assets and liabilities. Deferred tax assets and liabilities are measured using the currently enacted tax rates that apply to taxable income in effect for the years in which those tax attributes are expected to be recovered or paid, and are adjusted for changes in tax rates and tax laws when such changes are enacted.

The Company recognizes deferred tax assets to the extent that the Company believes that these assets are more-likely-than-not to be realized. Valuation allowances are recorded to reduce deferred tax assets when it is more-likely-than-not that the future tax benefit will not be realized. The assessment of whether or not a valuation allowance is required involves weighing both positive and negative evidence, including both historical and prospective information, with greater weight given to evidence that is objectively verifiable. A history of recent losses is negative evidence that is difficult to overcome with positive evidence. In evaluating prospective information there are four sources of taxable income: reversals of taxable temporary differences, items that can be carried back to prior tax years (such as net operating losses), pre-tax income, and prudent and feasible tax planning strategies. Adjustments to the deferred tax valuation allowances are made in the period when those assessments are made.

The Company accounts for uncertain tax positions using a two-step recognition threshold and measurement analysis method to determine the financial statement impact of uncertain tax positions taken or expected to be taken in a tax return. Differences between tax positions taken in a tax return and amounts recognized in the financial statements are recorded as adjustments to other long-term assets and liabilities, or adjustments to deferred taxes, or both. The Company records the related interest and penalties to income tax expense.

Net Income per Common Share

Basic net income per share is computed using the weighted average number of shares of common stock outstanding during the period. Diluted net income per share is computed using the sum of the weighted average number of shares of common stock outstanding during the period and, if dilutive, the weighted average number of potential shares of common stock, including the assumed exercise of stock options, unvested restricted stock and total shareholder return awards. The Company applies the two-class method to calculate its basic and diluted net income per share attributable to common stockholders. The two-class method is an earnings allocation formula that treats a participating security as having rights to earnings that otherwise would have been available to common stockholders. During periods in which the Company incurs net losses, both basic and diluted net loss per common share are calculated by dividing the net loss by the weighted-average shares of common stock outstanding and potentially dilutive securities are excluded from the calculation because their effect would be antidilutive.

Cash and Cash Equivalents

Cash and cash equivalents include savings deposits, certificates of deposit and money market funds that have original maturities of three months or less.

Restricted Cash

Restricted cash as of December 31, 2025 and 2024, represents primarily collateral for a letter of credit securing a lease obligation and a security deposit. The Company believes the carrying value of these assets approximates fair value.

Concentration of Risks and Limited Suppliers

Financial instruments which potentially subject the Company to concentrations of credit risk consist principally of trade accounts receivable. The Company periodically reviews its accounts receivable for collectability and estimates the allowance for credit losses based on an evaluation of customer credit worthiness, the age of the outstanding receivable, economic trends, historical experience and other information over the payment periods. The Company sells primarily to hospitals, independent diagnostic testing facilities, and radiopharmacies.

As of December 31, 2025 and 2024, no customer accounted for greater than 10% of accounts receivable, net. No customer accounted for greater than 10% of revenues for the years ended December 31, 2025, 2024 and 2023.

The Company relies on certain materials used in its development and manufacturing processes, some of which are procured from only one or a few sources. The failure of one of these suppliers to deliver on schedule could delay or interrupt the manufacturing or commercialization process and would adversely affect the Company’s operating results. In addition, a disruption in the commercial supply of, or a significant increase in the cost of one of the Company’s materials from these sources could have a material adverse effect on the Company’s business, financial condition, results of operations and cash flows.

The Company currently relies on Jubilant HollisterStier (“JHS”) as its significant manufacturer of DEFINITY and relied on JHS as its sole source manufacturer of NEUROLITE, Cardiolite and evacuation vials for TechneLite prior to the sale of such SPECT products to SHINE on January 1, 2026. Through December 31, 2025, the Company had Molybdenum-99 supply agreements with Institute for Radioelements of Belgium, NTP Radioisotopes and its subcontractor Australian Nuclear Science and Technology Organisation.

The following table sets forth revenues for each of the Company’s products representing 10% or more of revenues:

Inventory, Net

Inventory includes material, direct labor and related manufacturing overhead and is stated at the lower of cost and net realizable value on a first-in, first-out basis. The Company records inventory when the Company takes title to the product. The majority of the value of the inventory relates to non-radioactive products. With respect to the Company’s products that are radiopharmaceuticals, due to the limited shelf life of such products, they are generally not held as finished goods.

The Company assesses the recoverability of inventory to determine whether adjustments for excess and obsolete inventory are required. Inventory that is in excess of future requirements is written down to its estimated net realizable value based on product shelf life, forecasted demand and other factors.

Inventory costs associated with product that has not yet received regulatory approval are capitalized if the Company believes there is probable future commercial use of the product and future economic benefits of the asset. If future commercial use of the product is not probable, then inventory costs associated with such product are expensed as incurred. As of December 31, 2025, the Company had $0.6 million of such product costs included in inventory related to PYLARIFY that have been purchased to support the new formulation of our PSMA PET imaging agent, which is awaiting regulatory approval. The Company had no inventory pending regulatory approval as of December 31,2024.

Property, Plant and Equipment, Net

Property, plant and equipment are stated at cost. Replacements of major units of property are capitalized, and replaced properties and equipment are retired. Replacements of minor components of property and repair and maintenance costs are charged to expense as incurred. Certain costs to obtain or develop computer software are capitalized and amortized over the estimated useful life of the software. Depreciation and amortization are computed on a straight-line basis over the estimated useful lives of the related assets and recorded in costs of goods sold and operating expenses in the associated functional expense category which utilizes the associated asset. The estimated useful lives of the major classes of depreciable assets are as follows:

Upon retirement or other disposal of property, plant and equipment, the cost and related amount of accumulated depreciation are removed from the asset and accumulated depreciation accounts, respectively. The difference, if any, between the net asset value and the proceeds is included in operating expenses in the accompanying consolidated statements of operations.

Included within machinery and equipment are spare parts. Spare parts include replacement parts relating to plant & equipment and are either recognized as an expense when consumed or reclassified and capitalized as part of the related asset and depreciated over the remaining useful life of the related asset.

Assets Held for Sale

The Company classifies an asset as held for sale when management, having the authority to approve the action, commits to a plan to sell the asset, the sale is probable within one year and the asset is available for immediate sale in its present condition. The Company also considers whether an active program to locate a buyer has been initiated, whether the asset is marketed actively for sale at a price that is reasonable in relation to its current fair value and whether actions required to complete the plan indicate that it is unlikely that significant changes to the plan will be made or that the plan will be withdrawn. The Company initially measures an asset that is classified as held for sale at the lower of its (i) carrying amount or (ii) fair value less costs to sell. Any loss resulting from this measurement is recognized in the period in which the held for sale criteria are met. Conversely, gains are not recognized until the date of sale. The Company assesses the fair value of an asset less costs to sell each reporting period that the asset remains classified as held for sale and reports any subsequent changes as an adjustment to the carrying amount of the asset, as long as the new carrying amount does not exceed the carrying amount of the asset at the time it was initially classified as held for sale. Assets are not depreciated or amortized while they are classified as held for sale.

Business Combinations

The Company accounts for business combinations using the acquisition method of accounting. The Company recognizes the assets acquired and liabilities assumed in business combinations on the basis of their fair values at the date of acquisition using its best estimates and assumptions. The Company assesses the fair value of assets acquired, including intangible assets, and liabilities assumed using a variety of methods. Each asset acquired and liability assumed is measured at fair value from the perspective of a market participant. The Company allocates the purchase price based on the relative fair value the assets acquired and liabilities assumed. The method used to estimate the fair values of intangible assets incorporates significant assumptions regarding the estimates a market participant would make in order to evaluate an asset, including a market participant’s use of the asset and the appropriate discount rates. Acquired in-process research and development (“IPR&D”) is recognized at fair value and initially characterized as an indefinite-lived intangible asset, irrespective of whether the acquired IPR&D has an alternative future use. Any excess purchase price over the fair value of the net tangible and intangible assets acquired is allocated to goodwill. Transaction costs and restructuring costs associated with a business combination are expensed as incurred.

During the measurement period, which extends no later than one year from the acquisition date, the Company may record certain adjustments to the carrying value of the assets acquired and liabilities assumed with the corresponding offset to goodwill. After the measurement period, all adjustments are recorded in the consolidated statements of operations as operating expenses or income.

Goodwill

Goodwill is not amortized but is instead tested for impairment at least annually and whenever events or circumstances indicate that it is more likely than not that it may be impaired. The Company has elected to perform the annual test for goodwill impairment as of October 31st of each year.

In performing the Company’s annual assessment, the Company is permitted to first perform a qualitative test and if necessary, perform a quantitative test. If the Company is required to perform the quantitative impairment test of goodwill, the Company compares the fair value of a reporting unit to its carrying value. If the reporting unit’s carrying value exceeds its fair value, the Company would record an impairment loss to the extent that the carrying value of goodwill exceeds its implied fair value. The Company estimates the fair value of its reporting units using discounted cash flow or other valuation models, such as comparative transactions and market multiples. The Company performed a qualitative assessment and didnot recognize any goodwill impairment charges during the years ended December 31,2025, 2024 or 2023.

Intangible and Long-Lived Assets

The Company tests intangible and long-lived assets for recoverability whenever events or changes in circumstances suggest that the carrying value of an asset or group of assets may not be recoverable. The Company measures the recoverability of assets to be held and used by comparing the carrying amount of the asset to future undiscounted net cash flows expected to be generated by the asset. If those assets are considered to be impaired, the impairment equals the amount by which the carrying amount of the assets exceeds the fair value of the assets. Any impairments are recorded as permanent reductions in the carrying amount of the assets. See Note 7,“Property, Plant and Equipment, Net” to these consolidated financial statements for further details on impairment. Long-lived assets, other than goodwill and other intangible assets that are held for sale are recorded at the lower of the carrying value or the fair market value less the estimated cost to sell.

Intangible assets, consisting of patents, trademarks, customer relationships, a currently marketed product, licenses and developed technology related to the Company’s products are amortized in a method equivalent to the estimated utilization of the economic benefit of the asset.

Costs of IPR&D intangible assets acquired as part of an asset acquisition that have no alternative future use are expensed when incurred. Milestone payments made after regulatory approval are capitalized as an intangible asset and amortized over an estimated useful life of the product. Cash payments related to acquired IPR&D intangible assets are reflected as an investing cash flow in the Company's consolidated statement of cash flows.

The Company’s IPR&D intangible assets include intangible assets acquired in a business combination that are used in research and development (R&D) activities but have not yet reached technological feasibility, regardless of whether they have alternative future use. The primary basis for determining the technological feasibility or completion of these projects is obtaining regulatory approval to market the underlying products in an applicable geographic region. Because obtaining regulatory approval can include significant risks and uncertainties, the eventual realized value of the acquired IPR&D projects may vary from their fair value at the date of acquisition. The Company classifies IPR&D intangible assets acquired in a business combination as an indefinite-lived intangible asset until the completion or abandonment of the associated R&D efforts. Upon completion of the associated R&D efforts, the Company will determine the useful life and begin amortizing the assets to reflect their use over their remaining lives. Upon permanent abandonment, the Company writes-off the remaining carrying amount of the associated IPR&D intangible asset. IPR&D intangible assets are tested at least annually as of October 31st or when a triggering event occurs that could indicate a potential impairment and any impairment loss is recognized in the Company’s consolidated statements of operations. See Note 10,“Intangibles, Net and Goodwill” to these consolidated financial statements for further details on impairment.

Contingencies

In the normal course of business, the Company is subject to loss contingencies, such as legal proceedings and claims arising out of its business, that cover a wide range of matters, including, among others, product and environmental liability. The Company records accruals for those loss contingencies when it is probable that a liability will be incurred and the amount of loss can be reasonably estimated. The Company does not recognize gain contingencies until realized.

Convertible Notes

The Company evaluates convertible notes to determine if those contracts or embedded components of those contracts qualify as derivatives to be separately accounted for. The change in fair value of any separately recognized derivative is recorded in the consolidated statement of operations as other income or expense. Upon conversion, exercise or cancellation of a derivative instrument, the instrument is marked to fair value at the date of conversion, exercise or cancellation.

Investments

Equity investments with readily determinable fair values for which the Company does not have significant influence over the investee are measured at fair value on a recurring basis. Equity investments without readily determinable fair values for which the Company does not have significant influence over the investee are measured at cost with adjustments for observable changes in price or impairments (referred to as the measurement alternative). For equity investments for which the Company does not have significant influence over the investee, changes in the value of unsold equity investments are recorded in investment in equity securities – unrealized (gain) loss in the Company’s consolidated statements of operations. Equity investments for which the Company has significant influence over the investee are measured using the equity method unless the Company elects to apply the fair value option to account for the investment.

Fair Values of Financial Instruments

The estimated fair values of the Company’s financial instruments, including its cash and cash equivalents, accounts receivable, accounts payable and accrued expenses approximate the carrying values of these instruments due to their short term nature. The Company’s long-term debt has triggering events that would impact the fair value of the instruments. The Company determined that no triggering event has occurred during the years ended December 31, 2025 and 2024. As of December 31, 2025 and 2024, the fair value of the Company’s convertible debt was estimated to be approximately $659.5 million and $765.3 million, respectively, based on quoted market prices of these instruments and was classified as a Level 1 measurement within the fair value hierarchy. For more information on the fair value, see Note 4,“Fair Value of Financial Instruments”to these consolidated financial statements.

Contingent Consideration Liabilities

The Company's acquisitions accounted for as asset acquisitions may include contingent consideration payments to be made for development, regulatory, and sales-based milestones. The Company first assesses whether such contingent consideration payments meet the definition of a derivative. Contingent consideration payments in an asset acquisition not required to be accounted for as derivatives are recognized when the contingency is resolved, and the consideration is paid or becomes payable. Contingent consideration payments required to be accounted for as derivatives are recorded at fair value on the date of the acquisition and are subsequently remeasured to fair value at each reporting date. Upon recognition of the contingent consideration payment, the amount is included in the cost of the acquired asset or group of assets.

The Company's acquisitions accounted for as business combinations include contingent consideration payments to be made for development, regulatory, and sales-based milestones, as well as potential payments to be made pursuant to an assumed contract. The estimated fair value of contingent consideration liabilities are initially measured and recorded on the acquisition date. The contingent consideration liabilities are considered to be Level 3 instruments and are reviewed and updated quarterly, or whenever events or circumstances occur that indicate a change in fair value. The contingent consideration liabilities are recorded at fair value at the end of each reporting period with changes in estimated fair values recorded in general and administrative expenses in the consolidated statements of operations.

The estimated fair value is determined based on probability adjusted discounted cash flow (“DCF”) and Monte Carlo simulation models that include significant estimates and assumptions pertaining to regulatory and commercialization events and sales targets. Significant changes in any of these inputs could result in a significantly higher or lower fair value measurement of the contingent consideration liabilities.

Derivative Instruments

The Company has used interest rate swaps to reduce the variability in cash flows associated with a portion of the Company’s forecasted interest payments on its variable rate debt. To qualify for hedge accounting, the hedging instrument must be highly effective at reducing the risk from the exposure being hedged. Further, the Company must formally document the hedging relationship at inception and, on at least a quarterly basis, continually reevaluate the relationship to ensure it remains highly effective throughout the life of the hedge. The Company does not enter into derivative financial instruments for speculative or trading purposes.

Advertising and Promotion Costs

Advertising and promotion costs are expensed as incurred. During the years ended December 31,2025, 2024 and 2023, the Company incurred $16.4 million, $29.7 million and $26.0 million, respectively in advertising and promotion costs, which are included in sales and marketing in the consolidated statements of operations.

Research and Development

Research and development costs are expensed as incurred and relate primarily to the development of new products to add to the Company’s portfolio and costs related to its medical affairs and medical information functions. Nonrefundable advance payments for goods or services that will be used or rendered for future R&D activities are deferred and recognized as an expense as the goods are delivered or the related services are performed.

Foreign Currency

The consolidated statements of operations of the Company’s foreign subsidiaries are translated into U.S. dollars using weighted-average exchange rates. The net assets of the Company’s foreign subsidiaries are translated into U.S. dollars using the end of period exchange rates. The impact from translating the net assets of these subsidiaries at changing rates are recorded in the foreign currency translation adjustment account, which is included in accumulated other comprehensive loss in the consolidated balance sheets.

Remeasurement of the Company’s foreign currency denominated transactions are included in net income. Transaction gains and losses are reported as a component of other income, net in the consolidated statements of operations.

Stock-Based Compensation

The Company’s stock-based compensation cost is measured at the grant date of the stock-based award based on the fair value of the award and is recognized as expense, net of estimated forfeitures, over the requisite service period, which generally represents the vesting period. The Company estimates the fair value of each stock-based award on its measurement date using either the current market price of the stock, the Black-Scholes option valuation model or the Monte Carlo simulation valuation model, whichever is most appropriate. The Black-Scholes and Monte Carlo simulation valuation models incorporate assumptions such as stock price volatility, the expected life of options or awards, a risk-free interest rate and dividend yield. The Company estimates forfeitures at the time of grant and revises those estimates in subsequent periods if actual forfeitures differ from those estimates. The Company uses historical data to estimate forfeitures and records stock-based compensation expense only for those awards that are expected to vest.

Expected volatility is based on the historical volatility of the Company’s stock price. The risk-free interest rates are based on quoted U.S. Treasury rates for securities with maturities approximating the awards’ expected lives. Expected lives are principally based on the Company’s historical exercise experience with previously issued awards. The expected dividend yield iszero as the Company has never paid dividends and does not currently anticipate paying any in the foreseeable future.

Expense for performance restricted stock awards is recognized based upon the fair value of the awards on the date of grant and the number of shares expected to vest based on the terms of the underlying award agreement and the requisite service period(s).

Other Income, Net

Other income, net consisted of the following:

(1)

$5.0 million recognized in December 2025 related to the achievement of a 2025 net sales milestone for RELISTOR as a part of the purchase price consideration outlined in the 2023 Healthcare Royalty Management LLC Royalty Interest agreement.

(2)

See Note 9,”Asset Retirement Obligations,”for more information.

Comprehensive Income

Comprehensive income consists of net income and other gains and losses affecting stockholders’ equity that, under U.S. GAAP, are excluded from net income. For the Company, other comprehensive income consists of foreign currency translation gains and losses. The accumulated other comprehensive loss balance consists entirely of foreign currency translation gains and losses.

Asset Retirement Obligations

The Company’s compliance with federal, state, local and foreign environmental laws and regulations may require it to remove or mitigate the effects of the disposal or release of chemical substances in jurisdictions where it does business or maintains properties. The Company establishes accruals when those costs are legally obligated and can be reasonably estimated. Accrual amounts are estimated, which may include the assistance of third-party environmental specialists, and are based on currently available information, regulatory requirements, remediation strategies, historical experience, the relative shares of the total remediation costs, a relevant discount rate, and the time periods of when estimated costs can be reasonably predicted. Changes in these assumptions could impact the Company’s future reported results.

The Company has production facilities which manufacture and process radioactive materials at its sites in North Billerica, Massachusetts and, through March 1, 2024, Somerset, New Jersey. The Company considers its legal obligation to remediate its facilities upon a decommissioning of its radioactive-related operations as an asset retirement obligation. The fair value of a liability for asset retirement obligations is recognized in the period in which the liability is incurred. As of December 31, 2025, the Company estimates the decommissioning and decontaminating costs for all their manufacturing sites to be approximately $20.4 million. The liability is measured at the present value of the obligation expected to be incurred and is adjusted in subsequent periods as accretion expense is recorded. The corresponding asset retirement costs are capitalized as part of the carrying values of the related long-lived assets and depreciated over the assets’ useful lives.

The Company has identified conditional asset retirement obligations related to the future removal and disposal of asbestos contained in certain of the buildings located on the Company’s North Billerica campus. The Company believes the asbestos is appropriately contained and it is compliant with all applicable environmental regulations. If these properties undergo major renovations or are demolished, certain environmental regulations are in place, which specify the manner in which asbestos must be handled and disposed. The Company is required to record the fair value of these conditional liabilities if they can be reasonably estimated. As of December 31, 2025 and 2024, sufficient information was not available to estimate a liability for such conditional asset retirement obligations as the obligations to remove the asbestos from these properties have indeterminable settlement dates. As such, no liability for conditional asset retirement obligations has been recorded in the accompanying consolidated balance sheets as of December 31, 2025 and 2024.

Self-Insurance Reserves

The Company’s consolidated balance sheets at December 31, 2025 and 2024 include $3.5 million and $2.8 million of accrued liabilities associated with employee medical costs that are retained by the Company, respectively. The Company estimates the required liability of those claims on an undiscounted basis based upon various assumptions which include, but are not limited to, the Company’s historical loss experience and projected loss development factors. The required liability is also subject to adjustment in the future based upon changes in claims experience, including changes in the number of incidents (frequency) and change in the ultimate cost per incident (severity).

Leases

In accordance with Accounting Standards Codification (“ASC”) 842, “Leases,” the Company determines if an arrangement is or contains a lease at inception. The Company has leases for vehicles, corporate offices and certain equipment. A contract is or contains a lease if the contract conveys the right to control the use of an identified asset for a period of time in exchange for consideration. The Company classifies leases at the lease commencement date as operating or finance leases and records a right-of-use asset and a lease liability on the consolidated balance sheets for all leases with an initial lease term of greater than twelve months. Leases with an initial term of twelve months or less are not recorded on the balance sheets, but payments are recognized as expense on a straight-line basis over the lease term. The Company has elected not to record a right-of-use asset or lease liability for leases with terms of twelve months or less.

A lease qualifies as a finance lease if any of the following criteria are met at the inception of the lease: (i) there is a transfer of ownership of the leased asset to the Company by the end of the lease term, (ii) the Company holds an option to purchase the leased asset that it is reasonably certain to exercise, (iii) the lease term is for a major part of the remaining economic life of the leased asset, (iv) the present value of the sum of lease payments equals or exceeds substantially all of the fair value of the leased asset, or (v) the nature of the leased asset is specialized to the point that it is expected to provide the lessor no alternative use at the end of the lease term.

Finance and operating lease assets and liabilities are recognized at the lease commencement date based on the present value of the lease payments over the lease term using the discount rate implicit in the lease. If the rate implicit is not readily determinable, the Company utilizes an estimate of its incremental borrowing rate based upon the available information at the lease commencement date, which may include comparing interest rates in the market for similar borrowings with comparable credit quality of the Company. Operating lease right-of-use (“ROU”) assets are further adjusted for prepaid or accrued lease payments. Operating lease payments are expensed using the straight-line method as an operating expense over the lease term. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Finance lease assets are amortized to depreciation expense using the straight-line method over the shorter of the useful life of the related asset or the lease term. Finance lease payments are bifurcated into (i) a portion that is recorded as imputed interest expense and (ii) a portion that reduces the finance liability associated with the lease.

ROU assets and lease liabilities are reassessed and remeasured when amendments to the terms of the lease agreement require reassessment and remeasurement of the lease payments and other inputs to the calculation of ROU assets and lease liabilities. The Company accounts for remeasurements and modifications to lease liabilities using the present value of remaining lease payments and estimated incremental borrowing rate at the date of remeasurement. The adjustment to the lease liability is recognized as a gain or loss in operating expenses, or as an adjustment to the ROU asset, as appropriate, based on the terms and conditions within the lease that are amended.

Recent Accounting Pronouncements

The Company has considered all new accounting standards issued by the Financial Accounting Standards Board (“FASB”).

Accounting Pronouncements Adopted During the Period

In December 2023, the FASB issued Accounting Standards Update (“ASU”) 2023-09,“Income Taxes (Topic 740): Improvements to Income Tax Disclosures,” which requires enhanced income tax disclosures, including specific categories and disaggregation of information in the effective tax rate reconciliation, disaggregated information related to income taxes paid, income or loss from continuing operations before income tax expense or benefit, and income tax expense or benefit from continuing operations. The requirements of the ASU are effective for annual periods beginning after December 15, 2024, with early adoption permitted. The Company adopted ASU 2023-09 prospectively and the disclosures included in this Annual Report on Form 10-K (“Form 10-K”) reflect the disclosures required under ASU 2023-09. See Note 5,“Income Taxes,”to these consolidated financial statements for more information.

Accounting Pronouncements Not Yet Adopted

In December 2025, the FASB issued ASU 2025-11,“Interim Reporting (Topic 270) Narrow-Scope Improvements,”which clarifies that the interim reporting requirements in Topic 270 apply to all entities that issue interim financial statements prepared in accordance with U.S. GAAP and consolidates such requirements within Topic 270. The amendments provide a comprehensive list within Topic 270 of required interim disclosures, establishes a principle requiring disclosure of events or changes occurring after the end of the most recent annual reporting period that have a material impact on interim results and clarifies the form and content requirements applicable to interim financial statements. The requirements of ASU 2025-11 are effective for interim reporting periods within annual reporting periods beginning after December 15, 2027 (for the Company’s Form 10-Q for the three months ending March 31, 2028). The Company is currently in the process of evaluating the effects of this pronouncement on its consolidated financial statements and related disclosures.

In September 2025, the FASB issued ASU 2025-06,“Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Targeted Improvements to the Accounting for Internal-Use Software,”which simplifies the capitalization guidance by removing all references to software development project stages so that the guidance is neutral to different software development methods. Entities will now capitalize costs associated with internal-use software only when management has authorized and committed funding, and it is probable that the project will be completed and the software will be used to perform its intended function. ASU 2025-06 is effective for interim and annual periods beginning after December 15, 2027, with early adoption permitted. The Company is currently in the process of evaluating the effects of this pronouncement on its consolidated financial statements and related disclosures.

In July 2025, the FASB issued ASU 2025-05,“Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses for Accounts Receivable and Contract Assets,”which provides a practical expedient related to the estimation of expected credit losses for accounts receivable and current contract assets that arise from transactions accounted for under ASC 606,“Revenue Recognition.”ASU 2025-05 requires an entity to disclose whether it has elected to use the practical expedient. An entity that makes the accounting policy election is required to disclose the date through which subsequent cash collections are evaluated. The requirements of ASU 2025-05 are effective for annual periods beginning after December 15, 2025, and interim periods beginning in the first quarter of 2026. Early adoption is permitted in both interim and annual reporting periods in which financial statements have not yet been issued or made available for issuance. The Company is currently in the process of evaluating the effects of this pronouncement and believes that the adoption will not have a material impact on its consolidated financial statements and related disclosures.

In November 2024, the FASB issued ASU 2024-04, “Debt - Debt with Conversion and Other Options (Subtopic 470-20),”which clarifies the requirements for determining whether certain settlements of convertible debt instruments should be accounted for as an induced conversion rather than as extinguishment of debt. The requirements of ASU 2024-04 are effective for the annual periods beginning after December 15, 2025, including interim periods within those fiscal years. Early adoption is permitted. For the Company, the requirements under ASU 2024-04 will be effective for its Form 10-Q for the first quarter of 2026. The adoption of ASU 2024-04 is not expected to have a material impact on the Company’s consolidated financial statements and related disclosures in 2026.

In November 2024, the FASB issued ASU 2024-03, “Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40),”and in January 2025, the FASB issued ASU 2025-01,“Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40): Clarifying the Effective Date.”ASU 2024-03 requires additional income statement disclosures, including the disaggregation of specific categories of expenses underlying the line items presented on the income statement. Additionally, ASU 2024-03 requires enhanced disclosure of selling expenses. As clarified by ASU 2025-01, the requirements of the guidance are effective for annual periods beginning after December 15, 2026 and interim periods within fiscal years beginning after December 15, 2027. For the Company, annual reporting requirements under ASU 2024-03 will be effective for its Form 10-K for the year ending December 31, 2027 and interim reporting requirements will be effective beginning in the first quarter of 2028. Early adoption is permitted and the amendments should be applied on a prospective basis, however retrospective application is permitted. The Company is currently in the process of evaluating the impact of this pronouncement on its consolidated financial statements and related disclosures.

3. Revenue from Contracts with Customers

Revenue Recognition

Revenue is recognized when a customer obtains control of promised goods or services. The amount of revenue recognized reflects the consideration to which the Company expects to be entitled to receive in exchange for these goods or services. To achieve this core principle, the Company applies the following five steps: (1) identify the contracts with a customer; (2) identify the performance obligations in the contract; (3) determine the transaction price; (4) allocate the transaction price to the performance obligations in the contract; and (5) recognize revenue when (or as) the Company satisfies a performance obligation.

Disaggregation of Revenue

The following table summarizes revenue by revenue source as follows:

(1)

The Company’s product revenue includes PYLARIFY, DEFINITY, Neuraceq and TechneLite among other products. This category represents the delivery of physical goods. The Company applies the same revenue recognition policies and judgments for all of its principal products.

The Company classifies its revenues into three product categories: Radiopharmaceutical Oncology, Precision Diagnostics, and Strategic Partnerships and Other Revenue. Radiopharmaceutical Oncology includes PYLARIFY and historically included AZEDRA. In the first quarter of 2024, the Company discontinued the production of AZEDRA. Precision Diagnostics includes DEFINITY, Neuraceq, TechneLite and other diagnostic imaging products. Strategic Partnerships and Other Revenue primarily includes revenue derived from partnerships with pharmaceutical companies and academic institutions that use the Company’s commercial or investigational products in clinical trials as research tools, royalties and other milestone payments received from the Company’s strategic partners that have commercialized products pursuant to license arrangements with the Company, as well as contract development and manufacturing organization (“CDMO”) revenue generated by Evergreen.

Revenue by product category on a net basis is as follows:

The following table presents the Company’s revenue by geographic region determined by location of customer or other party for the periods presented:

Product Revenue, Net

The Company sells its products principally to hospitals, independent diagnostic testing facilities, and radiopharmacies. The Company considers customer purchase orders, which in some cases are governed by master sales or group purchasing organization agreements, to be the contracts with a customer.

For each contract, the Company considers the promise to transfer products, each of which is distinct, to be the identified performance obligations. In determining the transaction price, the Company evaluates whether the price is subject to refund or adjustment to determine the net consideration to which the Company expects to be entitled.

The Company typically invoices customers upon satisfaction of identified performance obligations. As the Company’sstandard payment terms are 30 to 60 days from invoicing, the Company has elected to use the significant financing component practical expedient.

The Company allocates the transaction price to each distinct product based on its relative standalone selling price. The product price as specified on the purchase order is considered the standalone selling price as it is an observable input which depicts the price as if sold to a similar customer in similar circumstances.

Revenue is recognized when control of the product is transferred to the customer (i.e., when the Company’s performance obligation is satisfied), which typically occurs upon delivery to the customer. Further, in determining whether control has transferred, the Company considers if there is a present right to payment and legal title, along with risks and rewards of ownership having transferred to the customer.

Frequently, the Company receives orders for products to be delivered over multiple dates that may extend across several reporting periods. The Company invoices for each delivery subsequent to shipment and recognizes revenues for each distinct product when transfer of control has occurred.

The Company generally does not separately charge customers for shipping and handling costs, but any shipping and handling costs charged to customers are included in product revenue, net. Taxes collected from customers relating to product sales and remitted to governmental authorities are excluded from revenues.

Variable Consideration

Revenues from product sales are recorded at the net sales price (transaction price), which includes estimates of variable consideration for which reserves are established for discounts, returns, rebates and allowances that are offered within contracts between the Company and its customers. These reserves are based on the amounts earned or to be claimed on the related sales and are classified as a current liability. Where appropriate, these estimates take into consideration a range of possible outcomes which are probability-weighted for relevant factors such as the Company’s historical experience, current contractual and statutory requirements, specific known market events and trends, industry data and forecasted customer buying and payment patterns. Overall, these reserves reflect the Company’s best estimates of the amount of consideration to which it is entitled based on the terms of the contract. The amount of variable consideration included in the transaction price may be constrained, and is included in the net sales price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized will not occur in a future period. Actual amounts of consideration ultimately received may differ from the Company’s estimates. If actual results in the future vary from the Company’s estimates, the Company adjusts these estimates, which would affect product revenue and earnings in the period such variances become known.

Rebates

Estimates for rebates represent the Company’s estimated obligations under contractual arrangements with third parties. Rebate accruals are recorded in the same period the related revenue is recognized, resulting in a reduction of revenue and the establishment of a liability which is included in accrued expenses and other current liabilities in the Company’s consolidated balance sheets. These rebates result from performance-based offers that are primarily based on attaining contractually specified sales volumes and growth, Medicaid rebate programs for the Company’s products, administrative fees of group purchasing organizations and certain distributor-related commissions. The calculation of the accrual for these rebates is based on an estimate of the third-party’s expected purchases and the resulting applicable contractual rebate to be earned over a contractual period.

Product Returns

The Company generally offers customers a limited right of return due to non-conforming product. The Company estimates the amount of its product sales that may be returned by its customers and records this estimate as a reduction of revenue in the period the related product revenue is recognized. The Company currently estimates product return liabilities using its historical product return information and considers other factors that it believes could significantly impact its expected returns, including product recalls. Reserves for product returns are not significant to the Company due to the nature of its products including radiopharmaceutical products with limited half-lives.

An analysis of the amount of, and change in, reserves is summarized as follows:

License and Royalty Revenues

The Company has entered into licensing agreements, under which it licenses certain rights to third parties. The terms of these arrangements typically include payment to the Company of one or more of the following: non-refundable, up-front license fees; development, regulatory and commercial milestone payments; and royalties on net sales of licensed products. The Company also has distribution licenses which are treated as combined performance obligations with the delivery of its products and are classified as product revenue, net.

In determining the appropriate amount of revenue to be recognized as it fulfills its obligations under each of its agreements, the Company performs the five-step approach stated earlier. The Company uses judgment in determining the number of performance obligations in a license agreement by assessing whether the license is distinct or should be combined with another performance obligation, as well as the nature of the license. As part of the accounting for these arrangements, the Company must develop assumptions that require judgment to determine the stand-alone selling price for each performance obligation identified in the contract. The Company uses key assumptions to determine the stand-alone selling price, which may include market conditions, reimbursement rates for personnel costs, development timelines and probabilities of regulatory success.

Licenses of Intellectual Property

If the license to the Company’s intellectual property is determined to be distinct from the other performance obligations identified in the arrangement, the Company recognizes revenues from non-refundable, up-front fees allocated to the license when the license is transferred to the customer and the customer is able to use and benefit from the license. For licenses that are bundled with other promises, the Company utilizes judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue from non-refundable, up-front fees. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition.

Milestone Payments

At the inception of each arrangement that includes development or sales milestone payments, the Company evaluates whether the milestones are considered probable of being reached and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are outside the control of the Company or the licensee, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. The transaction price is then allocated to each performance obligation on a relative stand-alone selling price basis, for which the Company recognizes revenue as or when the performance obligations under the contract are satisfied. At the end of each subsequent reporting period, the Company re-evaluates the probability of achievement of such milestones and any related constraint, and if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect license and royalty revenues and earnings in the period of adjustment. At December 31, 2025, the variable consideration for the milestone payments is constrained and is excluded from contract price until the milestone is achieved by the customer.

Royalty Revenues

For arrangements that include sales-based royalties, including milestone payments based on the level of sales, and the license is deemed to be the predominant item to which the royalties relate, the Company recognizes revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied).

CDMO Revenue

The Company generates a small amount of CDMO revenue providing contract development and manufacturing services to emerging and mid‑sized radiopharmaceutical companies developing alpha‑ and beta‑emitting diagnostic and therapeutic products across early‑ to late‑stage clinical development, with the ability to support commercial supply. The Company prices these contracts based on the scope and complexity of services, including the number of batches or doses, laboratory and personnel requirements, contract duration, isotope utilized, and prevailing market conditions.

The Company assesses each agreement involving CDMO services to determine if there are multiple performance obligations, and allocates revenue to each performance obligation based on its stand-alone selling price relative to the stand-alone selling prices of other performance obligations within the contract. CDMO contracts generally have defined terms, generally one to two years; however, the timing of satisfaction of performance obligations is typically contingent on customer clinical trial progress and development timelines. The Company recognizes revenue when it satisfies each performance obligation, which is generally when services are completed and quality-approved products are shipped and title transfers to the customer.

Contract Assets and Liabilities

The Company recognizes an asset for incremental costs of obtaining a contract with a customer if it expects to recover those costs. The Company’s sales incentive compensation plans qualify for capitalization since these plans are directly related to sales achieved during a period of time. However, the Company has elected the practical expedient to expense the costs as they are incurred, within sales and marketing expenses, since the amortization period is less than one year.

The following table provides a roll forward of deferred revenue:

The Company didnot record any revenue related to performance obligations satisfied (or partially satisfied) in previous periods during the years ended December 31,2025 and 2024.

The Company is required to allocate a portion of its revenue received from commercial contracts to future reporting periods to the extent the Company had performance obligations that extended beyond one year. However, the Company’s performance obligations are typically part of contracts that have an original expected duration of one year or less. Therefore, since the Company elected the practical expedient under ASC 606-10-50-14, it does not disclose information regarding performance obligations which are part of contracts that have an original expected duration of one year or less.

4. Fair Value of Financial Instruments

Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. In order to increase consistency and comparability of fair value measurements, financial instruments are categorized based on a hierarchy that prioritizes observable and unobservable inputs used to measure fair value into three broad levels, which are described below:

•

Level 1 — Inputs are unadjusted quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date.

•

Level 2— Inputs include quoted prices for similar assets and liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability (i.e., interest rates, yield curves, etc.) and inputs that are derived principally from or corroborated by observable market data by correlation or other means (market corroborated inputs).

•

Level 3 — Unobservable inputs that reflect the Company’s estimates about the assumptions that market participants would use in pricing the asset or liability. The Company develops these inputs based on the best information available, including its own data.

The Company’s financial assets and liabilities that are measured at fair value on a recurring basis consist of money market funds, deferred compensation plan liabilities, contingent consideration liabilities and equity investments. The Company invests excess cash from its operating cash accounts in overnight investments and reflects these amounts in cash and cash equivalents in the consolidated balance sheets at fair value using quoted prices in active markets for identical assets. Investment in equity securities resulting from the Perspective Therapeutics, Inc. (“Perspective”) and Radiopharm Theranostics Limited (“Radiopharm”) strategic agreements were recorded at fair value by the Company and are adjusted for price changes observable in the market each quarter. The Company recorded the contingent consideration liabilities resulting from the acquisitions of Progenics, Evergreen and Life Molecular at fair value based on inputs that are not observable in the market.

The tables below present information about the Company’s assets and liabilities measured at fair value on a recurring basis:

Nonqualified Deferred Compensation Plan

The Company maintains the Lantheus Nonqualified Deferred Compensation Plan (the “LDCP”) for the benefit of certain key, highly-compensated employees and non-employee directors. The assets of the LDCP are invested in corporate-owned life insurance (“COLI”) and mutual funds at December 31, 2025. The mutual funds are classified as Level 1 of the fair value hierarchy because they are valued using quoted market prices. There were no assets or liabilities balances in the LDCP at December 31, 2024. The liabilities of the LDCP are presented in other long-term liabilities in the Company’s consolidated balance sheets. See Note 18,“Benefit Plans”for more information on the LDCP.

Perspective Therapeutics, Inc. Equity Securities

At December 31, 2025, the Company held 11,677,339 shares of Perspective common stock (“Perspective Shares”). The Company accounts for its investment in Perspective Shares as an equity investment with a readily determinable fair value, as the securities are publicly traded on the New York Stock Exchange (“NYSE”). The fair value of the Perspective Shares is based on their closing price on the NYSE at the end of the fiscal period and is classified within Level 1 of the fair value hierarchy because the equity securities are valued using quoted market prices. The fair value of the Perspective Shares as of December 31,2025 was approximately$32.1 million based on a closing market price of$2.75 per share on December 31, 2025, resulting in an unrealized loss of$5.1 million for the year ended December 31, 2025. The fair value of the Perspective Shares as of December 31, 2024 was approximately$37.3 million based on a closing market price of$3.19 per share on December 31, 2024, resulting in an unrealized loss of$41.0 million for the year ended December 31, 2024. See Note 19,“Acquisitions,” to these consolidated financial statements for further discussion of the Perspective transaction.

Radiopharm Theranostics Limited Equity Securities

At December 31, 2025, the Company held 537,958,513 shares of Radiopharm common stock (“Radiopharm Shares”). The Company accounts for its investment in Radiopharm Shares as an equity investment with a readily determinable fair value, as the securities are publicly traded on the Australian Stock Exchange (“ASX”). The fair value of the Radiopharm Shares is based on their closing price on the ASX at the end of the fiscal period and is classified within Level 1 of the fair value hierarchy because the equity securities are valued using quoted market prices. The fair value of the Radiopharm Shares as of December 31,2025 was approximately$9.0 million based on the converted closing market price of approximately$0.02 per share on December 31, 2025, resulting in an unrealized loss on equity securities of$3.3 million for the year ended December 31, 2025. The fair value of the Radiopharm Shares as of December 31, 2024 was approximately$2.2 million based on the converted closing market price of approximately$0.01 per share on December 31, 2024, resulting in an unrealized loss on equity securities of$2.6 million for the year ended December 31, 2024. See Note 19,“Acquisitions”to these consolidated financial statements for further discussion of the Radiopharm transaction.

Contingent Consideration

Progenics

The Company assumed contingent consideration liabilities related to a previous acquisition completed by Progenics in 2013 (“2013 Acquisition”). These contingent consideration liabilities include potential payments of up to $70.0 million if the Company attains certain net sales targets primarily for AZEDRA and 1095 (also known as 131 I-MIP-1095) and a $5.0 million 1095 commercialization milestone. Additionally, there is a potential payment of up to $10.0 million for a commercialization milestone related to a prostate cancer product candidate the Company refers to as “1404” that was out-licensed to ROTOP Pharmaka GmbH. The Company’s total potential payments related to the 2013 Acquisition are approximately $85.0 million. The Company considers the contingent consideration liabilities relating to the 2013 Acquisition each a Level 3 instrument (one with significant unobservable inputs) in the fair value hierarchy. The estimated fair value of these was determined based on probability adjusted discounted cash flows and Monte Carlo simulation models that included significant estimates and assumptions pertaining to commercialization events and sales targets. The most significant unobservable inputs with respect to 1095 and 1404 are the probabilities of achieving regulatory approval of those development projects and subsequent commercial success.

Significant changes in any of the probabilities of success, the probabilities as to the periods in which sales targets and milestones will be achieved, discount rates or underlying revenue forecasts would result in a higher fair value measurement. The Company records the contingent consideration liabilities at fair value with changes in estimated fair values recorded in general and administrative expenses in the consolidated statements of operations. The Company can give no assurance that the actual amounts paid, if any, in connection with the contingent consideration liabilities, will be consistent with any recurring fair value estimate of such contingent consideration liabilities. The Company estimated that the probability of successfully meeting the sales targets and commercialization milestones described above was zero, as the Company discontinued the production of AZEDRA in the first quarter of 2024 and the Company is not actively advancing 1095. As a result of this assessment, the Company determined the value of the contingent consideration liabilities to be $0 at December 31, 2025 and 2024.

Evergreen Theragnostics, Inc.

Pursuant to the terms of the Agreement and Plan of Merger (the “Evergreen Merger Agreement”) with Evergreen and Shareholder Representative Services LLC governing the Company's acquisition of Evergreen in April 2025 (see Note 19,“Acquisitions”), the Company is required to pay up to $727.5 million in cash upon the achievement of specified milestones in connection with the development and commercialization of certain milestone products, as defined in the Evergreen Merger Agreement, and Octevy (also referred to as LNTH-2501), a registrational-stage PET diagnostic imaging agent targeting neuroendocrine tumors. The Company records these possible payments as contingent consideration liabilities that are classified within Level 3 of the fair value hierarchy. The Company estimated the fair value of the contingent consideration liabilities associated with the sales milestones using a Monte Carlo simulation in a risk-neutral framework, whereby the achievement of the future revenue associated with the sales milestones was simulated using a geometric Brownian motion model. The Company estimated the fair value of the contingent consideration liability associated with the development and commercialization milestones using a probability-weighted DCF approach. The most significant unobservable inputs with respect to these milestone products and Octevy, are the revenue volatility and probabilities of achieving regulatory milestones, respectively. A significant change in probability of payment of the first regulatory milestone payment for Octevy could result in a material fluctuation in the value of the contingent consideration liability.

Life Molecular Imaging Limited

Pursuant to the terms of the Sale and Purchase Agreement (the “LMI Purchase Agreement”) with Life Medical Group Limited (“Life Medical”) in connection with the Company’s acquisition of Life Molecular in July 2025 (see Note 19, “Acquisitions”), the Company is required to make certain earn-out and milestone payments as a percentage of and upon achievement of specified net sales thresholds, respectively, of Neuraceq and certain other imaging and tracing agents in Life Molecular’s pipeline. These contingent cash earn-out and milestone payments total up to $400.0 million.

In addition to the net sales earn-out and milestone payments, the Company also assumed a contingent consideration liability owed to Piramal Holdings SA (“Piramal”), pursuant to an assumed contract (the “Piramal SPA”). The Company is required to make cash payments of up to $30.0 million upon the achievement of specified earnings metrics of Life Molecular, as defined in the Piramal SPA.

The Company estimated the fair value of the contingent consideration liabilities using a Monte Carlo simulation model in a risk-neutral framework, whereby the achievement of the future revenue and other specified earnings metrics associated with the contingent payments were simulated using a geometric Brownian motion model. The most significant unobservable inputs with respect to Neuraceq and other imaging and tracing agents in Life Molecular’s pipeline include revenue volatility and the probability of commercial success. A significant change in the revenue volatility or forecasted commercial revenue could result in a material fluctuation in the value of the contingent consideration liability.

The following tables summarize quantitative information and assumptions pertaining to the fair value measurement of liabilities using Level 3 inputs as of December 31,2025:

Unobservable inputs were weighted by the relative fair value of the contingent consideration liability. There wereno liabilities with fair values that were measured using Level 3 inputs as of December, 31, 2024.

For those financial instruments with significant Level 3 inputs, the following table summarizes the activities for the periods indicated:

5. Income Taxes

The components of income before income taxes consists of the following:

The Company’s income tax expense consists of the following:

The table below provides the updated requirements of ASU 2023-09 for 2025. See Note 2,“Summary of Significant Accounting Policies - Recent Accounting Pronouncements”for additional detail on the adoption of ASU 2023-09.

The reconciliation of income taxes at the U.S. federal statutory rate to the income tax expense is as follows:

(1)

State and local taxes in California, Florida, Illinois, New York, New York City and Pennsylvania made up the majority (greater than 50 percent) of the tax effect in this category.

As previously disclosed for the years ended December 31, 2024 and 2023, prior to the adoption of ASU 2023-09, the effective income tax rate differs from the statutory federal income tax rate as follows:

Income taxes paid (net of refunds) are as follows:

(1)

Includes $3.5 million of California payments.

The components of deferred income tax assets (liabilities) are as follows:

On July 4, 2025, the One Big Beautiful Bill Act (the “OBBBA”) was enacted. The OBBBA provides for significant U.S. tax law changes, including the permanent extension of certain expiring provisions of the Tax Cuts and Jobs Act, modifications to the international tax framework, and the restoration of favorable tax treatment for certain business provisions. These provisions did not have a material impact on the Company’s effective income tax rate for 2025. The change in the Company’s deferred tax balances for 2025 was primarily related to the acquisitions of Life Molecular and Evergreen and the expensing of previously capitalized R&D expenses, for tax purposes, under the OBBBA.

The Company regularly assesses its ability to realize its deferred tax assets. Assessing the realizability of deferred tax assets requires significant management judgment. In determining whether its deferred tax assets are more-likely-than-not realizable, the Company evaluated all available positive and negative evidence. As of December 31, 2025 and 2024, the Company maintains a valuation allowance of $18.7 million and $15.6 million, respectively. The amounts in 2025 and 2024 primarily relate to unrealized losses incurred during each year on the Company’s investment in equity securities and to net deferred tax assets of certain of the Company’s foreign subsidiaries.

Utilization of net operating loss carryforwards and R&D credit carryforwards may be subject to a substantial annual limitation due to ownership change limitations that could occur in the future in accordance with Section 382 of the Internal Revenue Code of 1986 (“IRC Section 382”) and with Section 383 of the Internal Revenue Code of 1986, as well as similar state provisions. These ownership changes may limit the amount of net operating loss carryforwards and R&D credit carryforwards that can be utilized annually to offset future taxable income and taxes, respectively. In general, an ownership change, as defined by IRC Section 382, results from transactions which impact the ownership of certain stockholders or public groups in the stock of a corporation by more than 50 percentage points over a three-year period.

At December 31, 2025, the Company had U.S. federal net operating loss carryforwards of approximately $281.4 million, $108.2 million of which will expire between 2029 and 2037, and $173.2 million of which can be carried forward indefinitely. The Company has foreign net operating losses of $76.3 million, $3.9 million of which expire between 2032 and 2035 and $72.4 million of which can be carried forward indefinitely. The Company’s state net operating losses are $9.2 million on a tax-effected basis, the majority of which will expire between 2032 and 2045. The Company has state research credit carryforwards of $3.4 million, which will expire between 2030 and 2040.

The Company’s U.S. federal income tax returns are subject to examination for three years after the filing date of the return. The state and foreign income tax returns are subject to examination for periods varying from three to six years after filing. The Company is currently undergoing tax examination in the United Kingdom for tax years 2018 to 2021 and in Germany for tax years 2020 to 2022.

A reconciliation of the Company’s changes in uncertain tax positions for 2025, 2024 and 2023 is as follows:

As of December 31, 2025 and 2024, total liabilities for uncertain tax positions, including interest and penalties, were $37.6 million and $9.4 million, respectively, consisting of uncertain tax positions of $35.5 million and $7.6 million, respectively, interest accruals of $2.1 million and $1.8 million, respectively, andno penalty accruals as of December 31,2025 and 2024. The increase in uncertain tax positions during the year ended December 31, 2025 was primarily related to tax uncertainties recorded in purchase accounting related to the LMI Acquisition. As of December 31, 2025, $29.6 million and $8.0 million of these liabilities were recorded in other long-term liabilities and as a reduction of deferred tax assets, respectively. As of December 31,2024, $1.4 million, $7.3 million and $0.7 million of these liabilities were recorded in current liabilities, other long-term liabilities, and as a reduction of deferred tax assets, respectively. As of December 31,2025, the Company has $32.0 million of unrecognized tax benefits which would impact the effective tax rate if recognized.

6. Inventory, Net

Inventory, net, consisted of the following:

(1)

As of December 31, 2025, amounts totaling $4.0 million, $3.5 million and $4.2 million were reclassified to assets held for sale, from raw materials, work in process and finished goods, respectively, as a result of the then-pending sale of the Company’s single-photon emission computerized tomography (“SPECT”) business. See Note 8,“Assets and Liabilities Held for Sale”for more information.

The majority of the value of the inventory relates to non-radioactive products. With respect to the Company’s products that are radiopharmaceuticals, due to the limited shelf life of such products, they are generally not held as finished goods.

7. Property, Plant and Equipment, Net

Property, plant and equipment, net, consisted of the following:

(1)

As of December 31, 2025, amounts totaling $6.5 million in land, $48.1 million in buildings, $37.5 million in machinery, equipment and fixtures, $0.5 million in computer software, $6.2 million in construction in progress and $49.6 million in accumulated depreciation and amortization were reclassified to assets held for sale as a result of the then-pending sale of the Company’s SPECT business. See Note 8,“Assets and Liabilities Held for Sale”for more information.

Depreciation and amortization expense related to property, plant and equipment, net, was $22.5 million, $20.4 million and $13.2 million for the years ended December 31,2025, 2024 and 2023, respectively.

The Company tests long-lived assets for recoverability whenever events or changes in circumstances suggest that the carrying value of an asset or group of assets may not be recoverable.

During 2023, as a result of a decline in expected future cash flows related to the AZEDRA marketed intangible asset, the Company recorded anoncash impairment of $6.0 million in cost of goods sold in the accompanying consolidated statements of operations.

On January 8, 2024, the Company entered into an agreement with Perspective to transfer the sublease for the Company’s Somerset, New Jersey facility (the “Somerset Facility”) and sold the associated assets at the Somerset Facility for $8.0 million. The transfer of the sublease and completion of the asset sale occurred on March 1, 2024. The sale of assets resulted in a derecognition to the right-of-use asset of $0.4 million, the lease liability of $0.4 million and remaining property, plant and equipment of $0.8 million. The Company also incurred commission expense of $1.0 million related to the transaction. The Company recorded a gain on sale of assets of $6.3 millionin operating income in the accompanying consolidated statements of operations for the year ended December 31, 2024. See Note 19,“Acquisitions”for more further discussion of the Perspective transaction.

During the fourth quarter of 2024, the Company completed the sale of a portion of its North Billerica campus for $9.8 million in cash. The Company recorded a gain on sale of assets of $2.1 million in operating income in the accompanying consolidated statements of operationsfor the year ended December 31, 2024.

8. Assets and Liabilities Held for Sale

SPECT Business

On May 1, 2025, the Company entered into a definitive agreement to sell its SPECT business to SHINE Technologies, LLC (“SHINE”), a wholly-owned subsidiary of Illuminated Holdings, Inc. Under the terms of the agreement, SHINE will acquire the assets and liabilities associated with the Company’s SPECT business, including its approved products (TechneLite, NEUROLITE, Xenon Xe-133 Gas, and Cardiolite) and the portion of the North Billerica, Massachusetts campus that manufactures the Company’s SPECT products and SPECT-related Canadian operations. The transaction was subject to customary closing conditions and completed on January 1, 2026.

As of December 31, 2025, assets and liabilities associated with the Company’s SPECT business have been presented in the Company’s consolidated balance sheets as assets and liabilities held for sale as it was determined that these assets and liabilities met the criteria to be classified as such under ASC 360,“Impairment or disposal of long-lived assets,”and will continue to be classified as such until the transaction is completed. The Company determined that the fair value less costs to sell exceeded the carrying value of the assets and liabilities associated with the SPECT business, and thereforeno indicator of impairment was present with respect to these assets during 2025. The Company does not believe the sale represents a strategic shift having a major effect on the Company's consolidated financial results and therefore does not meet the criteria for classification as discontinued operations.

The table below presents the carrying amounts of assets and liabilities held for sale related to the SPECT transaction:

See Note 21,“Subsequent Events,”to these consolidated financial statements for subsequent event involving the Company’s sale of its SPECT business to SHINE.

9. Asset Retirement Obligations

The Company considers its legal obligation to remediate its facilities upon a potential decommissioning of its radioactive-related operations as an asset retirement obligation (“ARO”). The Company has production facilities which manufacture and process radioactive materials at its sites in North Billerica, Massachusetts and, through March 1, 2024, Somerset, New Jersey. As of December 31, 2025, the ARO is measured at the present value of the expenses estimated to be incurred in such remediation and is approximately $20.4 million.

The following table provides a summary of the changes in the Company’s carrying value of asset retirement obligations:

(1)

Amount reclassified to liabilities held for sale as a result of the then-pending sale of the assets and liabilities associated with the Company’s SPECT business. See Note 8,“Assets and Liabilities Held for Sale”for more information.

During the year ended December 31, 2025, the Company revised certain inputs to its estimate of decommissioning costs expected to be incurred throughout the period of remediation, which reduced the estimate of remediation costs by $4.7 million. This reduction was primarily the result of changes in the technology and processes used for the remediation activities from those contemplated in the estimate previously provided in 2022, and was recorded in other income on the Company's consolidated statements of operations in the first quarter of 2025. During the year ended December 31, 2025, the Company recorded an additional reduction of $1.5 million to the ARO for remediation efforts completed during the period.

The Company is required to provide the Massachusetts Department of Public Health financial assurance demonstrating the Company’s ability to fund the decommissioning and decontaminating of its North Billerica, Massachusetts facility in the event of any closure. The Company has provided this financial assurance in the form of a $30.3 million surety bond.

10. Intangibles, Net and Goodwill

Goodwill

The following table represents the change in the carrying value of goodwill from January 1 to December 31, 2025:

(1)

Amount reclassified to liabilities held for sale as a result of the then-pending sale of the assets and liabilities associated with the Company’s SPECT business. See Note 8,“Assets and Liabilities Held for Sale”for more information.

Intangibles, Net

Intangibles, net, consisted of the following:

The Company recorded amortization expense for its intangible assets of $47.1 million, $43.8 million and $46.4 million for the years ended December 31,2025, 2024 and 2023, respectively.

In June 2024, the Company entered into an agreement with the stockholders of Meilleur (“Meilleur Stockholders”) to purchase all of the outstanding capital stock of Meilleur (which holds the rights under a license agreement to develop and commercialize NAV-4694) for approximately $32.9 million. The Company recorded a developed technology intangible asset of $40.3 million as a result of the purchase price and the specific assets and liabilities of Meilleur that were acquired as part of the asset acquisition based on their value at the agreed upon closing date. In August 2024, upon successful completion of a technology transfer, the Company paid $10.0 million to the Meilleur Stockholders. This additional contingent payment was capitalized as part of the asset cost and increased the total value of the Company’s developed technology intangible assets. See Note 19,“Acquisitions” to these consolidated financial statements for further discussion of the acquisition of Meilleur.

The below table summarizes the estimated aggregate amortization expense expected to be recognized on the above intangible assets:

11. Accrued Expenses and Other Current and Long-Term Liabilities

Accrued expenses and other current and long-term liabilities are comprised of the following:

12. Long-Term Debt and Other Borrowings, Net of Current Portion

As of December 31,2025, the Company’s maturities of principal obligations under its long-term debt and other borrowings are as follows:

2022 Revolving Facility

In December 2024, the Company entered into an amendment to its $350.0 million five-year revolving credit facility originally entered into in 2022. The amendment, among other things, increased the facility from $350.0 million to $750.0 million (as amended, the “2022 Revolving Facility”) and extended the maturity date from December 2, 2027 to December 19, 2029. Under the terms of the 2022 Revolving Facility, the lenders are committed to extending credit to the Company from time to time consisting of revolving loans (the “Revolving Loans”) in an aggregate principal amount not to exceed $750.0 million (the “Revolving Commitment”) at any time, including a $40.0 million sub-facility for the issuance of letters of credit (the “Letters of Credit”) and a $20.0 million sub-facility for swingline loans (the “Swingline Loans”). The Revolving Loans, Letters of Credit, and the Swingline Loans, if used, are expected to be used for working capital and for other general corporate purposes.

The Revolving Loans bear interest, with pricing based from time to time at the Company’s election, at (i) the secured overnight financing rate as published by the Federal Reserve Bank of New York on its website plus an applicable margin that ranges from 1.25% to 2.00% based on the Company’s total net leverage ratio or (ii) the alternative base rate plus an applicable margin that ranges from 0.25% to 1.00%, in either case, based on the Company’s total net leverage ratio. The 2022 Revolving Facility also includes an unused commitment fee at a rate ranging from 0.15% to 0.30% per annum based on the Company’s total net leverage ratio. Interest associated with the unused commitment is recorded to accrued expenses and other current and long-term liabilities on the consolidated balance sheet and paid out on a quarterly basis.

The Company is permitted to voluntarily prepay the Revolving Loans, in whole or in part, or reduce or terminate the Revolving Commitment, in each case, without premium or penalty. On any business day on which the total amount of outstanding Revolving Loans, Letters of Credit and Swingline Loans exceeds the total Revolving Commitment, the Company must prepay the Revolving Loans in an amount equal to such excess. The Company is not required to make mandatory prepayments under the 2022 Revolving Facility. As of December 31, 2025, there wereno outstanding borrowings under the 2022 Revolving Facility.

The Company has the right to request an increase to the Revolving Commitment in an aggregate principal amount of up to the greater of $685.0 million (so that the total amount available would be approximately $1.44 billion)or 100% of consolidated earnings before interest, taxes, depreciation and amortization for the four consecutive fiscal quarters most recently ended, plus additional amounts in certain circumstances (collectively, the “Incremental Cap”), minus certain incremental term loans made pursuant to specified incremental term loan commitments (“Incremental Term Loans”). The Company has the right to request Incremental Term Loans in an aggregate principal amount of up to the Incremental Cap less any incremental increases to the Revolving Commitment. Proceeds of Incremental Term Loans may be used for working capital and for other general corporate purposes and will bear interest at rates agreed between the Company and the lenders providing the Incremental Term Loans.

2022 Revolving Facility Covenants

The 2022 Revolving Facility contains a number of affirmative, negative and reporting covenants, as well as financial maintenance covenants pursuant to which the Company is required to be in quarterly compliance, measured on a trailing four quarter basis, withtwo financial covenants. The minimum interest coverage ratio must be at least 3.00 to 1.00. The maximum total net leverage ratio permitted by the financial covenant is 3.50 to 1.00, other than in connection with certain acquisitions, in which case, the maximum total net leverage ratio permitted can be increased to 4.00 to 1.00.

The 2022 Revolving Facility contains usual and customary restrictions on the ability of the Company and its subsidiaries to: (i) incur additional indebtedness (ii) create liens; (iii) consolidate, merge, sell or otherwise dispose of all or substantially all of its assets; (iv) sell certain assets; (v) pay dividends on, repurchase or make distributions in respect of capital stock or make other restricted payments; (vi) make certain investments; (vii) repay subordinated indebtedness prior to stated maturity; and (viii) enter into certain transactions with its affiliates.

Upon an event of default, the Administrative Agent (as defined in the 2022 Revolving Facility) will have the right to declare the loans and other obligations outstanding under the 2022 Revolving Facility immediately due and payable and all commitments immediately terminated.

The 2022 Revolving Facility is guaranteed by Lantheus Holdings, and certain subsidiaries of Lantheus Medical, including Progenics and Lantheus Real Estate, and obligations under the 2022 Revolving Facility are generally secured by first priority liens over substantially all of the assets of each of Lantheus Medical, Lantheus Holdings, and certain subsidiaries of Lantheus Medical, including Progenics and Lantheus Real Estate (subject to customary exclusions set forth in the transaction documents) owned as of December 2, 2022 or thereafter acquired.

2.625% Convertible Senior Notes due December 2027

On December 8, 2022, the Company issued $575.0 million in aggregate principal amount of 2.625% Convertible Senior Notes due December 2027 (the “Notes”), which includes $75.0 million in aggregate principal amount of Notes sold pursuant to the full exercise of the initial purchasers’ option to purchase additional Notes. The Notes were issued under an indenture, dated as of December 8, 2022 (the “Indenture”), among the Company, Lantheus Medical, a wholly owned subsidiary of the Company, as guarantor, and U.S. Bank Trust Company, National Association, as Trustee. The net proceeds from the issuance of the Notes were approximately $557.8 million after deducting the initial purchasers’ discounts and offering expenses payable by the Company.

The Notes are senior unsecured obligations of the Company. The Notes are fully and unconditionally guaranteed on a senior unsecured basis by the Guarantor. The Notes bear interest at a rate of 2.625% per year, payable semi-annually in arrears on June 15 and December 15 of each year, beginning on June 15, 2023, and will mature on December 15, 2027 unless earlier redeemed, repurchased or converted in accordance with their terms. The initial conversion rate for the Notes is 12.5291 shares of the Company’s common stock per $1,000 in principal amount of Notes (which is equivalent to an initial conversion price of approximately $79.81 per share of the Company’s common stock, representing an initial conversion premium of approximately 42.5% above the closing price of $56.01 per share of the Company’s common stock on December 5, 2022). In no event shall the conversion rate per $1,000 in principal amount of Notes exceed 17.8539 shares of the Company’s common stock. Prior to the close of business on the business day immediately preceding September 15, 2027, the Notes may be converted at the option of the holders only upon occurrence of specified events and during certain periods, and thereafter until the close of business on the business day immediately preceding the maturity date, the Notes may be converted at any time. The Company will satisfy any conversion by paying cash up to the aggregate principal amount of the Notes to be converted and by paying or delivering, as the case may be, cash, shares of the Company’s common stock, or a combination of cash and shares of the Company’s common stock, at its election, in respect of the remainder, if any, of its conversion obligation in excess of the aggregate principal amount of the Notes being converted. The Company may redeem for cash all or any portion of the Notes, at its option, if the closing sale price per share of the Company’s common stock exceeds 130% of the conversion price of the Notes for a specified period of time. The redemption price will be equal to 100% of the principal amount of the Notes to be redeemed, plus accrued and unpaid interest, if any, to, but excluding, the redemption date.

The Company evaluated the Notes upon completion of the sale and concluded on the following features:

•

Conversion Feature: The Company determined that the conversion feature qualifies for the classification of equity. As a result, the conversion feature should not be bifurcated as a derivative instrument and the Notes were accounted for as a single liability.

•

Redemption Features: The redemption features were reviewed within the Notes and the Company determined that the redemption features are closely related to the Notes and as such should not be separately accounted for as a bifurcated derivative instrument.

•

Additional Interest Features: The Notes may result in additional interest if the Company fails to timely file any document or report that the Company is required to file with the Securities and Exchange Commission pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). The Company will pay additional interest on the Notes at a rate equal to 0.25% to 0.50% per annum based on the principal amount of Notes outstanding for each day the Company failure to file has occurred or the Notes are not otherwise freely tradable. Further, if the Notes are assigned a restricted CUSIP number or the Notes are not otherwise freely tradable pursuant to Rule 144 under the Securities Act of 1933, as amended, by holders other than Company affiliates or holders that were Company affiliates at any time during the three months immediately preceding as of the 385 th day after the last date of original issuance of the Notes, the Company will pay additional interest on the Notes at a rate equal to (i)0.25% to 0.50% per annum based on the principal amount of Notes outstanding for each day until the restrictive legend has been removed from the Notes, the Notes are assigned an unrestricted CUSIP and the Notes are freely tradable. The Company concluded that the interest feature is unrelated to the credit risk and should be bifurcated from the Notes, however, the Company assessed the probabilities of triggering events occurring under these features and does not expect to trigger the aforementioned events. These events will continue to be monitored to determine whether the interest feature will be bifurcated if it has value.

Holders of the Notes may require the Company to repurchase their Notes upon the occurrence of a fundamental change prior to the maturity at a repurchase price equal to 100% of the principal amount thereof, plus accrued and unpaid interest to, but excluding, the date of repurchase. In connection with certain triggering events, the Company will, under certain circumstances, increase the conversion rate for holders of the Notes who elect to convert their Notes in connection with such corporate events.

During the fourth quarter of 2025, the closing price of the Company’s common stock did not exceed 130% of the conversion price of the Notes for more than 20 trading days of the last 30 consecutive trading days of the quarter. As a result, the Notes are not convertible at the option of the holders of the Notes during the first quarter of 2026, the quarter immediately following the quarter when the conditions are met, as stated in the terms of the Notes. Because the Notes are not considered convertible under the terms of the Notes and pursuant to ASC 470-10, the Company classified the carrying value of the Notes as long-term debt, net and other borrowings on the Company’s consolidated balance sheets as of December 31,2025.

The Company recorded interest expense of approximately $15.1 million related to the Notes for the years ended December 31,2025, 2024 and 2023, respectively.

13. Stockholders’ Equity and Stock-Based Compensation

Equity Incentive Plans

As of December 31, 2025, the Company’s approved equity incentive plans included the 2015 Equity Incentive Plan (“2015 Plan”), the 2013 Equity Incentive Plan (“2013 Plan”), and the 2008 Equity Incentive Plan (“2008 Plan”). These plans are administered by the Board of Directors (the “Board”) and permit the granting of stock, stock options, stock appreciation rights, restricted stock, restricted stock units (“RSUs”) and dividend equivalent rights to employees, officers, directors and consultants of the Company.

The Company has certain stock option and restricted stock awards outstanding under each of its equity incentive plans but, upon adoption of the 2015 Plan, the Company no longer grants new equity awards under its 2008 and 2013 Plans. The Company adopted its 2015 Plan in June 2015 and subsequently amended the plan in April 2016, April 2017, February and April 2019, April 2021, April 2022 and April 2024, October 2024 and April 2025. The aggregate shares of common stock reserved for issuance under the 2015 Plan, as amended, is 14,930,277 shares.

Employee Stock Purchase Plan

The Lantheus Holdings, Inc. 2023 Employee Stock Purchase Plan, (the “2023 ESPP”) provides for the granting of up to 500,000 shares of the Company’s common stock to eligible employees. The 2023 ESPP allows eligible employees to contribute up to 15% of their qualifying compensation toward the semi-annual purchase of the Company’s common stock in March and September of each year, subject to an annual maximum dollar amount. The purchase price is the lesser of 85% of the fair market value of the stock on the last trading day of each Offering Period (as defined in the 2023 ESPP); or the first trading day of each Offering Period. The number of shares issued under the 2023 ESPP was 62,243 shares,67,920 shares and 34,345 shares in 2025, 2024 and 2023, respectively. The Company calculates the fair value of the shares issued under the 2023 ESPP using the Black-Scholes model at the commencement of an Offering Period in March and September of each year and the related expense is recorded over the Offering Period.

Stock-Based Compensation Expense

Stock-based compensation expense recognized in the consolidated statements of operations is summarized below:

Stock Options

Stock option awards under the 2015 Plan are granted with an exercise price equal to the fair value of the Company’s common stock at the date of grant. Stock option awards generally vest over three years; however, there are certain stock option awards with a vesting period of one year that are granted to certain employees and members of the Board. All option awards have aten-year contractual term.

A summary of stock option activity for 2025 is presented below:

The table below summarizes the key weighted-average assumptions used in valuing stock options granted:

During the years ended December 31, 2025, 2024 and 2023,171,101,209,657 and 214,619 options were exercised having aggregate intrinsic values of $7.1 million, $12.1 million and $12.9 million, respectively. The weighted average grant-date fair value of stock options granted was $49.19, $39.26 and $43.18 for the years ended December 31, 2025, 2024 and 2023, respectively.

As of December 31, 2025, there was $24.1 million of unrecognized compensation expense related to outstanding stock options, which is expected to be recognized over a weighted-average period of 2.0 years.

Restricted Stock Units

A summary of RSU activity for 2025 is presented below:

RSUs generally vest over three years; however, there are certain RSUs with a vesting period of one year that are granted to certain employees and members of the Board. As of December 31,2025, there was $65.1 million of unrecognized compensation expense related to outstanding RSUs, which is expected to be recognized over a weighted-average period of 2.0 years.

The weighted average grant-date fair value for RSUs granted during the fiscal years ended December 31, 2025, 2024 and 2023 was $84.92, $70.56 and $74.38 per share, respectively. The total fair value of restricted stock vested in fiscal years 2025, 2024 and 2023 was $43.5 million, $42.5 million and $18.3 million, respectively.

Total Stockholder Return Restricted Stock Awards

During the years ended December 31, 2025, 2024 and 2023, the Company granted total stockholder return (“TSR”) awards that include athree-year market condition where the performance measurement period isthree years. Vesting of the TSR awards is based on the Company’s level of attainment of specified TSR targets relative to the percentage appreciation of a specified index of companies for the respective three-year period and is also subject to the continued employment of the grantees. The number of shares that are earned over the performance period ranges from 0% to 200% of the initial award. The fair value of these awards is based on a Monte Carlo simulation valuation model with the following assumptions:

A summary of TSR award activity for 2025 is presented below:

As of December 31, 2025, there was $26.9 million of unrecognized compensation expense related to outstanding performance restricted stock which is expected to be recognized over a weighted-average period of 1.8 years.

The weighted average grant-date fair value for TSR awards granted during the fiscal years ended December 31, 2025, 2024 and 2023 was $163.50, $105.87 and $127.75 per share, respectively. The total fair value of TSR awards vested in fiscal years 2025, 2024 and 2023 was $36.2 million, $33.6 million and $8.2 million, respectively.

Modification of equity awards

In the fourth quarter of 2024, the Company reviewed its current capabilities and skillsets and began implementing organizational changes deemed necessary to best position the Company to execute on its long-term strategy. These changes included transitioning approximately 75 employees outof the Company. In connection with these changes, the Company approved equity modifications that allowed grants of stock options and RSUs issued to those impacted by this event to continue to vest in 2024 and 2025 with any unvested stock option and RSU grants as of December 31, 2025 to be cancelled. TSR awards grantedto these individuals will continue to vest on their original vesting schedule but any shares issued will be issued in a pro-rated amount based on the time served during the performance period. The incremental stock-based compensation expense resulting from these modifications recognized in 2024 was $2.7 million. Total costs related to these organizational changes were approximately $12.1 million.

Common Stock Repurchases

On July 31, 2025, the Board authorized a program to repurchase up to $400.0 million of shares of the Company’s common stock through December 31, 2027 (the “2025 Program”). The 2025 Program replaced the program authorized in November 2024 to repurchase up to $250.0 million of shares of the Company’s common stock (the “2024 Program”), including the remaining unused amounts under the 2024 Program, so there could be no additional repurchases under the 2024 Program subsequent to July 31, 2025. During 2025, the Company repurchased 1.3 million shares for approximately $100.0 million under the 2024 Program for an average stock price of $79.37. During 2025, the Company repurchased a total of 3.5 million shares for an aggregate purchase price of approximately $200.0 million under the 2025 Program for an average stock price of $56.72. A total of approximately $200.0 million of shares of the Company’s common stock remain available for repurchase under the 2025 Program.

14. Leases

The Company entered into an operating lease agreement in February 2022 to lease office space in Bedford, Massachusetts (“Existing Premises”), under a lease agreement expiring in June 2031 (the “Existing Premises Lease”), and on May 4, 2023, the Company modified the Existing Premises Lease. The lease modification includes a lease of additional office and laboratory space at the Bedford location (the “Additional Premises”) for a term of 15 years and 4 months and extends the term ofthe lease for the Existing Premises to be coterminous with the term of the lease for the Additional Premises. On October 7, 2024, the Company executed a second amendment to the Existing Premises Lease for additional space resulting in one additional operating lease, and as of December 31, 2025, this additional operating lease has not yet commenced. On February 14, 2025, the Company executed a third amendment to the Existing Premises Lease which included finalizing the conversion of the rent schedule from gross to triple net, resulting in a reduction of the Existing Premises Lease ROU asset and lease liability by $5.8 million. The future lease payments for this lease are approximately $17.0 million. The lease is expected to commence in 2026 and has a noncancellable lease term of 13.3 years.

On March 1, 2024, the Company transferred the sublease and completed the asset sale of the Somerset Facility. See Note 7,“Property, Plan and Equipment, Net” to these consolidated financial statements for further discussion on the sublease transfer.

Operating and finance lease assets and liabilities are as follows:

The components of lease expense were as follows:

Other information related to leases is as follows:

Future minimum lease payments under non-cancellable leases as of December 31,2025 were as follows:

15. Other Assets

Other assets are comprised of the following:

16. Net Income Per Common Share

A summary of net income per common share is presented below:

Impact of the Convertible Notes

The Company considers shares issuable upon conversion of the Notes to be common stock equivalents and are only included in the calculation of diluted net income per share when their effect is dilutive. The Company has the option to settle the Notes through cash settlement or a combination of cash and share settlement provided that the principal is settled in cash and the conversion spread is settled in cash or shares as elected by the Company. The Company considers the Notes to be participating securities through the two-class method. Per the terms of the indenture governing the Notes, the Company determined that if a cash dividend is paid that is greater than the stock price at the time such dividend is declared, the holders of the Notes will receive cash on an if-converted basis. While this feature is considered to be a participating right, basic income attributable to common shareholders is only impacted if the Company’s earnings per share exceeds the current share price, regardless of whether such dividend is declared. During the years ended December 31, 2025, 2024, and 2023, no such dividend was declared, and the Company’s earnings per share did not exceed its share price. The Company is required to settle the principal amount of the Notes in cash upon conversion, and convertibility of the Notes is dependent upon the Company’s share price. Therefore, the Company used the if-converted method for calculating the dilutive effect of the conversion option on diluted net income per share. The conversion option will have a dilutive impact on net income per share of Common Stock when the average price per share of the Company’s Common Stock for a given period exceeds the conversion price of the Notes of $79.81 per share. See Note 12,“Long-Term Debt and Other Borrowings, Net of Current Portion”to these consolidated financial statementsfor further discussion on the Notes.

17. Commitments and Contingencies

Purchase Commitments

The Company has entered into purchasing arrangements in which minimum quantities of goods or services have been committed to be purchased on an annual basis.

As of December 31,2025, future payments required under purchase commitments are as follows:

The Company has entered into agreements which contain certain percentage volume purchase requirements. The Company has excluded these future purchase commitments from the table above since there are no minimum purchase commitments or payments under these agreements.

License Agreements

The Company has entered into license agreements in which fixed payments have been committed to be paid on an annual basis.

As of December 31, 2025, no future fixed payments are required under license agreements. The Company may be required to pay approximately $4.9 billion in contingent payments under the Company’s license agreements. These contingent payments include potential milestone or contractual payment obligations contingent upon the achievement or occurrence of future milestones or events and the amounts and timing of such potential obligations are unknown or uncertain.

Legal Proceedings

From time to time, the Company is a party to various legal proceedings arising in the ordinary course of business. In addition, the Company has in the past been, and may in the future be, subject to investigations by governmental and regulatory authorities, which expose it to greater risks associated with litigation, regulatory or other proceedings, as a result of which the Company could be required to pay significant fines or penalties. The costs and outcome of litigation, regulatory or other proceedings cannot be predicted with certainty, and some lawsuits, claims, actions or proceedings may be disposed of unfavorably to the Company and could have a material adverse effect on the Company’s business, financial condition, results of operations and cash flows. In addition, intellectual property disputes often have a risk of injunctive relief which, if imposed against the Company, could materially and adversely affect its financial condition or results of operations. If a matter is both probable to result in material liability and the amount of loss can be reasonably estimated, the Company estimates and discloses the possible material loss or range of loss. If such loss is not probable or cannot be reasonably estimated, a liability is not recorded in its consolidated financial statements.

On January 26, 2024, the Company was sued in the United States District Court for the District of Delaware by Advanced Accelerator Applications USA, Inc. and Advanced Accelerator Applications SA, each a Novartis entity, for patent infringement in response to the filing of our Abbreviated New Drug Application and Paragraph IV certification in connection with PNT2003, consistent with the process established by the Hatch-Waxman Act. In December 2025, the court conducted its trial. As of the date of this Form 10-K, the Company is currently waiting for the court to issue its decision. Because the outcome of litigation is uncertain, the Company cannot predict how or when this matter will ultimately be resolved.

On February 23, 2024, the Company filed a patent infringement lawsuit against a healthcare-related imaging software developer, and that developer filed a motion to dismiss the case based on grounds of invalidity for certain patents and failure to state a claim for infringement for other patents. The court dismissed the developer’s motion to dismiss as to invalidity, and granted the motion as to certain allegations of infringement. Because the outcome of litigation is uncertain, the Company cannot predict how or when this matter will ultimately be resolved.

On September 9, 2025, an alleged stockholder initiated a putative securities class action against the Company in the United States District Court for the Southern District of New York, styled Margolis v. Lantheus Holdings, Inc., et al. The operative complaint also asserts claims against certain of the Company’s named executives. A related action, styled Indiana Pub. Ret. Sys. v. Lantheus Holdings, Inc., et al., was filed in the same court on November 5, 2025. Those actions are now consolidated into a single putative securities class action (captioned In re Lantheus Holdings, Inc. Secs. Litig.), the theory of which is that the defendants made materially false or misleading statements (or omitted material facts) in violation of the Exchange Act. Under the operative scheduling order in the case, the lead plaintiff may file an amended complaint by March 13, 2026. Additionally, on December 17, 2025, another alleged stockholder of the Company filed a shareholder derivative action in the same court, styled Lelchuk v. Heino et al., nominally on behalf of the Company and naming as defendants the current directors of the Board and the same officers named in the consolidated securities class action described above (a similar derivative complaint styled Jones v. Markison et al., was previously filed on October 31, 2025 but was voluntarily withdrawn without prejudice). The derivative complaint largely repeats the allegations asserted in the consolidated securities class action, and asserts claims for alleged breaches of fiduciary duties, aiding and abetting breach of fiduciary duty, unjust enrichment, waste of corporate assets, and violations of the Exchange Act. The plaintiff seeks damages and other relief on behalf of the Company. Because the outcome of litigation is uncertain, the Company cannot predict how or when these matters will ultimately be resolved.

As of December 31, 2025, the Company was not a party to any other material ongoing legal proceedings and has determined that the aforementioned matters are not expected to have a material adverse effect on its business or consolidated financial results.

Progenics

In connection with Lantheus Medical’s acquisition of Progenics in 2020, Lantheus Holdings issued 26,844,877 shares of Lantheus Holdings common stock and 86,630,633 contingent value rights (each a “CVR”) tied to the financial performance of PYLARIFY, to former Progenics stockholders and option holders. The Company remitted its final aggregate payment obligation under and in full satisfaction of the CVRs in May 2023.

18. Benefit Plans

Defined Contribution Plan

The Company maintains a qualified 401(k) plan (the “401(k) Plan”) for its U.S. employees. The 401(k) Plan covers U.S. employees who meet certain eligibility requirements. Under the terms of the 401(k) Plan, the employees may elect to make tax-deferred contributions through payroll deductions within statutory and plan limits, and the Company may elect to make non-elective discretionary contributions. The Company may also make optional contributions to the 401(k) Plan for any plan year at its discretion.

Expense recognized by the Company for matching contributions made to the 401(k) Plan was $9.8 million, $5.8 million, and $4.1 million for the years ended December 31,2025, 2024 and 2023, respectively.

Nonqualified Deferred Compensation Plan

In October 2024, the Company adopted the LDCP to provide key, highly-compensated employees and non-employee directors an additional opportunity for personal financial planning by allowing an option to defer a portion of their base salary and variable compensation each year. Under the LDCP, which is an elective nonqualified deferred compensation plan, employee participants are eligible to defer up to 80% of base salary and up to 80% of any bonus award beginning in 2025. For 2024, employee participants were not eligible to defer any base salary and could only defer up to 25% of their 2024 bonus award. Non-employee directors that are participants of the LDCP are eligible to defer up to 100% of their Board fees. Additionally, Company matching or employer contributions may be credited to the plan, although no such matching or employer contributions were made for 2024. Any matching or employer contributions cliff vest after the earlier of (i)five years, (ii) the participant reaching age 55, (iii) death, or (iv) disability. All amounts deferred or credited to a participant’s account (the “Deferred Amounts”) are held in a separate trust which was established by the Company to administer the LDCP. The LDCP assets held in trust by the Company to offset its obligation, which currently consist of COLI and could include mutual funds in future periods, are subject to the claims of the Company’s creditors in the event that the Company becomes insolvent. Consequently, the trust qualifies as a grantor trust for income tax purposes, or a Rabbi Trust (the “Trust”). Amounts deferred (and earnings on those amounts) are generally distributed following termination of employment unless the participant has elected an earlier distribution date, which may be no earlier than January 1st of the second year following the year of deferral. Vested Company matching or employer contributions (and earnings on those amounts) are generally distributed following termination of employment. Participants can elect to receive distributions in a lump sum, in annual installments over a period of not more than ten years for a qualifying distribution event (as defined in the LDCP), or in annual installments over a period of not more than five years if distributions are made prior to termination of employment.

As of December 31, 2025, assets and liabilities held by the Trust were $1.1 million and $0.9 million, respectively, and were included in other long-term assets, accrued expenses and other current and long-term liabilities in the Company’s consolidated balance sheets. There wereno assets and liabilities held by the Trust as of December 31, 2024. Changes in the value of the LDCP assets and liabilities are charged to investment in equity securities - unrealized loss and to general and administrative expenses, respectively, in the Company’s consolidated statements of operations and were de minimis in 2025.

19. Acquisitions

Acquisition of Businesses

Evergreen Theragnostics, Inc.

On April 1, 2025 (the “ Evergreen Closing Date”), the Company acquired all the issued and outstanding shares of Evergreen by means of a statutory merger of a subsidiary of the Company with and into Evergreen, with Evergreen surviving as the Company’s wholly-owned subsidiary (the “Evergreen Merger”), pursuant to the terms of the Evergreen Merger Agreement. Evergreen is a clinical-stage radiopharmaceutical company engaged in CDMO services as well as drug discovery and commercialization of proprietary products.

As consideration for the Evergreen Merger, the Company remitted an upfront payment of $276.4 million in cash. The upfront cash consideration included a $25.0 million milestone payment that was triggered prior to the Evergreen Closing Date, the cash settlement of the options and restricted stock units granted to certain Evergreen equity holders related to pre-acquisition services, which was recorded as a component of consideration transferred of $6.1 million, the settlement by the Company of thepre-existing Evergreen debt of $4.3 million, and the payment of transaction expenses paid by the Company on behalf of Evergreen of $11.6 million. In connection with the Evergreen Merger, certain equity awards that were outstanding and unvested prior to the acquisition became fully vested per terms of the merger agreement. The Company recognized $7.5 million of nonrecurring post-combination expense related to the acceleration and cash settlement of unvested historical Evergreen employee stock awards, which was recorded to operating expenses in the Company’s consolidated statements of operations in 2025.

In the event of achievement of specified milestones, the Company would be required to pay up to an additional $727.5 millionin cash pursuant to the Evergreen Merger Agreement. The potential remaining milestone payments are accounted for as contingent consideration, the fair value of which is determined using a Monte-Carlo simulation for sales milestones and a probability-weighted DCF approach for development and commercialization milestones. The fair value of the total contingent consideration is included in other long-term liabilities in the Company’s consolidated balance sheets at December 31, 2025.

The acquisition date fair value of the consideration transferred in the Evergreen Merger consisted of the following (in thousands):

The Evergreen Merger was accounted for as an acquisition of a business under ASC 805,“Business Combinations(“ASC 805”),”which requires that assets acquired and liabilities assumed on the acquisition date be recognized at their fair values as of the acquisition date. While the Company uses its best estimates and assumptions as part of the purchase price allocation process to value the assets acquired and liabilities assumed, its estimates and assumptions are subject to change during the measurement period. Fair value estimates are based on a complex series of judgments about future events and uncertainties and relies on estimates and assumptions. The judgments used to determine the estimated fair value assigned to each class of assets acquired and liabilities assumed, as well as asset lives, can materially impact the Company’s consolidated statements of operations.

As of December 31, 2025, the purchase accounting for the Evergreen Merger has not been finalized. As additional information becomes available, the Company may further revise its preliminary purchase price allocation during the remainder of the measurement period. The following table summarizes the fair values of assets acquired and liabilities assumed as of the date of acquisition:

(1)

The value approximates the gross contractual amount of accounts receivables. The contractual amount not expected to be collected is immaterial.

(2)

Intangible assets acquired consisted of IPR&D. The estimated fair values of the IPR&D assets were determined based on the present values of the expected cash flows to be generated by the respective underlying assets. The Company used a discount rate of 11.5% and cash flows that have been probability adjusted to reflect the risks of product commercialization, which the Company believes are appropriate and representative of market participant assumptions.

(3)

The goodwill recognized is attributable to future technologies that are not separately identifiable that could potentially add to the currently developed and pipeline products and Evergreen’s assembled workforce. Future technologies did not meet the criteria for recognition separately from goodwill because they are part of the future development and growth of the business. Goodwill of $116.2 million recognized in connection with the Evergreen Merger is not deductible for tax purposes.

Acquisition-related costs are not included as a component of consideration transferred but are expensed in the periods in which costs are incurred. The Company incurred $28.0 million of acquisition- and integration-related costs, including legal, accounting, compensation arrangements and other related fees in 2025. These costs are recorded in operating expenses in the consolidated statements of operations.

The results of operations attributable to the Evergreen Merger for 2025 were not material. Pro forma information has not been included as this acquisition did not have a material impact on the Company’s consolidated statements of operations in 2025.

Life Molecular Imaging Limited.

On July 21, 2025, Lantheus Radiopharm UK acquired the entire issued share capital of Life Molecular pursuant to the LMI Purchase Agreement with Life Medical, Life Healthcare Group Holdings Limited and Lantheus Medical as Lantheus Radiopharm UK’s guarantor (such acquisition, the “LMI Acquisition”). Life Molecular possesses an Alzheimer’s disease radiodiagnostic commercial infrastructure, R&D capabilities, and an established international footprint. The LMI Acquisition includes Neuraceq, an Alzheimer’s disease radiodiagnostic. Neuraceq is commercially approved in the United States, Canada, the European Union, the United Kingdom, Switzerland, China, Japan, South Korea, and Taiwan. As consideration for the LMI Acquisition, the Company remitted an upfront payment of $355.2 million in cash to Life Medical. In November 2025, the Company received a $2.3 million working capital settlement from Life Medical.

In connection with the LMI Acquisition, the Company could be required to pay up to an additional $400.0 million in potential earn-out and milestone payments as a percentage of and upon achievement of specified net sales thresholds, respectively, of Neuraceq and other pipeline assets. Additionally, the Company assumed a contingent consideration liability owed to Piramal (see Note 4,“Fair Value of Financial Instruments”), which is excluded from purchase consideration.

The potential remaining earn-out and milestone payments are accounted for as contingent consideration, the fair value of which is determined using a Monte-Carlo simulation in a risk-neutral framework. The fair value of the total contingent consideration is included in other long-term liabilities in the Company’s consolidated balance sheets at December 31, 2025.

The acquisition date fair value of the provisional consideration transferred in the LMI Acquisition consisted of the following:

The LMI Acquisition was accounted for as an acquisition of a business under ASC 805, which requires that assets acquired and liabilities assumed be recognized at their fair values as of the acquisition date. While the Company uses its best estimates and assumptions as part of the purchase price allocation process to value the assets acquired and liabilities assumed, its estimates and assumptions are subject to change during the measurement period. Fair value estimates are based on a complex series of judgments about future events and uncertainties and rely heavily on estimates and assumptions. The judgments used to determine the estimated fair value assigned to each class of assets acquired and liabilities assumed, as well as asset lives, can materially impact the Company’s consolidated statements of operations.

Asof December 31, 2025, the purchase accounting for the LMI Acquisition has not been finalized. As additional information becomes available, the Company may further revise its preliminary purchase price allocation during the remainder of the measurement period. Besides tax implications of the purchase price allocation, the final allocation may result in additional changesto other assets and liabilities. The following table summarizes the fair values of assets acquired and liabilities assumed as of the date of acquisition:

(1)

The value approximates the gross contractual amount of accounts receivables. The contractual amount not expected to be collected is immaterial.

(2)

Intangible assets acquired consisted of IPR&D and currently marketed products. The estimated fair values of the IPR&D and currently marketed product assets were determined based on the present values of the expected cash flows to be generated by the respective underlying assets. The Company used a discount rate of 23.5% and 23.0% for IPR&D and currently marketed products, respectively. IPR&D cash flows have been probability-adjusted to reflect the risks of technical and regulatory success of the products, which the Company believes are appropriate and representative of market participant assumptions. The Company estimates that the acquired currently marketed product asset has a useful life of 10.5 years.

(3)

The goodwill recognized is attributable to future technologies that are not separately identifiable that could potentially add to the currently developed and pipeline products and Life Molecular’s assembled workforce. Future technologies did not meet the criteria for recognition separately from goodwill because they are part of the future development and growth of the business. Goodwill of$63.2 million recognized in connection with the Life Molecular Merger is not deductible for tax purposes.

Acquisition-related costs are not included as a component of consideration transferred but are expensed in the periods in which costs are incurred. The Company incurred $36.7 million of acquisition- and integration-related costs, including legal, accounting, compensation arrangements and other related fees in 2025. These costs are recorded in operating expenses in the consolidated statements of operations.

The results of operations attributable to the LMI Acquisition for 2025 were not material. Pro forma information has not been included as this acquisition did not have a material impact on the Company’s consolidated statements of operations in 2025.

Acquisition of Assets

Exclusive License for PNT2003 & PNT2002

Under the terms of the PNT2003 License Agreement, the Company paid POINT Biopharma Global Inc. (“POINT”) an upfront cash payment of $10.0 million, and could pay up to an additional $34.5 million in milestone payments upon the achievement of specified U.S. and ex-U.S. regulatory milestones related to PNT2003. POINT is also eligible to receive up to $275.0 million in sales milestone payments upon the achievement of specified annual sales thresholds of PNT2003.

Under the terms of the PNT2002 License Agreement, the Company paid POINT an upfront cash payment of $250.0 million, and could pay up to an additional $281.0 million in milestone payments upon the achievement of specified U.S. and ex-U.S. regulatory milestones. POINT is also eligible to receive up to $1.3 billion in sales milestone payments upon the achievement of specified annual sales thresholds of PNT2002.

Additionally, the Company will pay POINT royalties on net sales, beyond certain financial thresholds and subject to conditions, of 15% for PNT2003 and 20% for PNT2002. Costs of IPR&D projects acquired as part of an asset acquisition that have no alternative future use are expensed when incurred, and therefore, a charge of $260.0 million was recognized in research and development expenses during the year ended December 31, 2022.

MK-6240

On February 6, 2023, the Company acquired Cerveau. Cerveau holds the rights under a license agreement to develop and commercialize MK-6240, a registrational stage F-18-labeled PET imaging agent that targets tau tangles in Alzheimer’s disease. The Company determined that upon review of its acquisition of Cerveau, the transaction did not meet the definition of a business combination and is therefore treated as an asset acquisition.

In February 2023, the Company made an upfront payment of approximately $35.3 million to the stockholders of Cerveau (the “Cerveau Stockholders”) and paid the Cerveau Stockholders an additional $10.0 million in May 2023 upon the successful completion of a technology transfer. The Company could pay up to an additional $51.0 million in milestone payments upon achievement of specified U.S. regulatory milestones related to MK-6240. The Cerveau Stockholders are also eligible to receive up to $1.2 billion in sales milestone payments upon the achievement of specified annual commercial sales thresholds of MK-6240, as well as up to $13.5 million in research revenue milestones upon achievement of specified annual research revenue thresholds. Additionally, the Company will pay to the Cerveau Stockholders up to double-digit royalty payments for research revenue and commercial sales. Research revenue is derived from existing partnerships with pharmaceutical companies and academic institutions that use MK-6240 in clinical trials. The purchase agreement pursuant to which the Company purchased Cerveau specified, among other things, that certain Cerveau Stockholders provide transition and clinical development services for a prescribed time following the closing of the transaction.

On January 8, 2024, the Company entered into an agreement with Perspective to participate in the next qualified financing to purchase Perspective Shares. On January 22, 2024, the Company purchased 56,342,355 Perspective Shares, representing 11.39% of the outstanding Perspective Shares, at the fair market offering price of $0.37 per share. Included within the agreement is a covenant which allows for the Company to designate one observer to Perspective’s board of directors. The observer has the option to attend any or all board meetings in a nonvoting capacity and the right to receive any board materials, except under certain instances where attorney-client privilege is necessary, where the material relates to a business or contractual relationship with the Company, to avoid bona fide conflict of interest, exposure of trade secrets or relating to a change of control transaction. The Company also purchased 60,431,039 Perspective Shares at a fair market purchase price of $0.95 per share as an investor in a private placement transaction on March 6, 2024, which resulted in the Company holding a cumulative 19.90% of the outstanding Perspective Shares (or 17.35% on a fully diluted basis) after giving effect to the closing of the private placement transa ction. The Company’s ownership has been further diluted since the original investment was made. The Company does not have the ability to exercise significant influence over operating and financial policies of Perspective based on its level of ownership of Perspective and because the Company’s board observer has no voting rights and there is otherwise no participation in policy-making processes, no interchange of managerial personnel, and no sharing of technology between the Company and Perspective.

Also effective January 8, 2024, the Company obtained the following options and rights from Perspective for an aggregate upfront payment of $28.0 million in cash:

•

An exclusive option from Perspective to negotiate for an exclusive license under the rights of Perspective and its affiliates to Perspective’s Pb212-VMT-α-NET, a clinical stage alpha therapy developed for the treatment of neuroendocrine tumors, to develop, manufacture, commercialize and otherwise exploit the VMT-α-NET Product.

•

A right to co-fund the investigational new drug (“IND”) application enabling studies for early-stage therapeutic candidates targeting prostate-specific membrane antigen and gastrin releasing peptide receptor and, prior to IND application filing, a right to negotiate for an exclusive license to such candidates.

•

A right of first offer and last look protections for any third party merger and acquisition transactions involving Perspective for a twelve-month period.

None of these options and rights have been exercised as of December 31, 2025.

Costs of IPR&D projects acquired as part of an asset acquisition that have no alternative future use are expensed when incurred, and therefore, a charge of $28.0 million was recognized in R&D expenses during the first quarter of 2024.

Also effective January 8, 2024, the Company entered into an agreement with Perspective to transfer the Somerset Facility and the associated assets at the Somerset Facility for $8.0 million. The transfer of the sublease and completion of the asset sale occurred on March 1, 2024 at which time the Company had no further continuing legal obligations related to the lease. See Note 7,“Property, Plant and Equipment, Net”to these consolidated financial statements for additional details.

On June 14, 2024 Perspective effected a 1-for-10 reverse stock split, after which the Company held 11,677,339 shares of Perspective’s common stock.

On June 15, 2024, the Company entered into an agreement with Radiopharm to acquire all of Radiopharm’s rights totwo licensed preclinical assets for an upfront payment of $2.0 million. The Company acquired global exclusive rights to both aleucine-rich repeat-containing protein 15 (“LRRC15”)-targeted radiotherapeutic and to a Trophoblast cell surface antigen-2 (“TROP2”)-targeted radiodiagnostic. LRRC15, which is also known as LNTH-2403, is a potential first-in-class, highly specific monoclonal antibody radio-conjugate with both Orphan Drug and Rare Pediatric Disease designations from the U.S. Food and Drug Administration (“FDA”) for the treatment of osteosarcoma. The agent is designed to target the surrounding tumor micro-environment cells expressing the protein potentially treating a broad range of cancers. The TROP2-targeted nanobody radio-conjugate, which is also known as LNTH-2404, is designed to target TROP2, an intracellular calcium signal transducer that is overexpressed in various types of adenocarcinomas with minimal expression in normal tissues and is associated with tumor aggressiveness, poor prognosis and drug resistance.

In connection with this acquisition, the Company assumed the underlying license agreements related to the two preclinical assets, together with their respective milestone and royalty payment obligations. The Company could pay up to an additional $20.0 million in milestone payments upon achievement of specified regulatory milestones. The Company could also pay up to an additional $6.5 million in sales milestone payments upon the achievement of specified annual commercial sales thresholds in the event the Company pursues commercialization, as well as royalty payments for commercial sales. Costs of IPR&D projects acquired as part of an asset acquisition that have no alternative future use are expensed when incurred, and therefore, a charge of $2.0 million was recognized in research and development expenses during 2024 related to the Radiopharm transaction.

During the third quarter of 2024, the Company purchased 149,625,180 shares of Radiopharm common stock (“Radiopharm Shares”), for an aggregate purchase price of approximately $5.0 million. During 2025, the Company purchased an aggregate additional 388,333,333 Radiopharm Shares for an aggregate purchase price of approximately $10.0 million. The Company does not have the ability to exercise significant influence over operating and financial policies of Radiopharm based on its ownership and because there is no participation in policy-making processes, no interchange of managerial personnel, and no sharing of technology between the Company and Radiopharm. See Note 4,“Fair Value of Financial Instruments,” for more information on the Company’s investment in Radiopharm.

On June 18, 2024, the Company acquired Meilleur, including its asset NAV-4694, an investigational late-stage F-18-labeled PET imaging agent that targets beta amyloids in Alzheimer’s disease. The Company determined that upon review of the Meilleur acquisition, the transaction did not meet the definition of a business combination and is therefore treated as an asset acquisition.

The Company made an upfront payment of approximately $32.9 million to the Meilleur Stockholders on June 18, 2024 and paid an additional $10.0 million in August 2024 after the successful completion of a technology transfer. The Company could pay up to an additional $43.0 million in milestone payments upon achievement of specified U.S. regulatory milestones related to NAV-4694. The Meilleur Stockholders are also eligible to receive up to $830.0 million in sales milestone payments upon the achievement of specified annual commercial sales thresholds of NAV-4694 as well as up to $4.0 million in remaining research milestones upon achievement of specified clinical studies at academic institutions. Additionally, in May 2025, the Company paid AstraZeneca AB (“AstraZeneca”) a $10.0 million one-time, non-refundable upfront payment to reduce the future commercial royalty obligations owed to AstraZeneca, pursuant to a NAV-4694 license agreement between AstraZeneca and Meilleur.

Research revenue is derived from existing partnerships with pharmaceutical companies and academic institutions that use NAV-4694 in clinical trials. Additionally, the Company could pay the Meilleur Stockholders up to double-digit royalty payments for research revenue and commercial sales.

RM2 Asset Purchase

On July 3, 2024, the Company acquired from Life Molecular theglobal rights to RM2, a gastrin-releasing peptide receptor-targeting agent, including the associated novel, clinical-stage radiotherapeutic and radiodiagnostic pair, referred to as

177Lu-DOTA-RM2 and 68Ga-DOTA-RM2, for an upfront payment of $35.0 million plus a $1.0 million payment made prior to the acquisition (the “RM2 Asset Purchase”), pursuant to the Sublicense, Development and Collaboration Agreement, by and between the Company and Life Molecular, dated as of June 27, 2024 (the “RM2 Sublicense Agreement”). Pursuant to the RM2 Sublicense Agreement, the Company has incurred €10.0 million in milestones achievements related to regulatory activities, and could have paid up to an additional €127.5 million in regulatory and development milestone payments upon achievement of clinical trial thresholds and approvals in different regions, up to €280 million in net sales milestones if products were commercialized and met certain sales thresholds, and royalties on net sales of RM2.

Costs of IPR&D projects acquired as part of an asset acquisition that have no alternative future use are expensed when incurred, and therefore, charges of $11.2 million in 2025 and $36.0 million in the third quarter of 2024 were recognized in R&D expenses related to the RM2 Asset Purchase.

In connection with the LMI Acquisition, the RM2 Sublicense Agreement wasamended to (i) reduce the contingent regulatory and development milestones by €45.0 million; (ii) assign the right to future payments from Life Molecular to its former parent, Life Medical; and (iii) eliminate certain other non-substantive rights contained in the RM2 Sublicense Agreement (the “RM2 Amendment”). The Company determined that the RM2 Amendment did not constitute settlement of a pre-existing relationship in accordance with ASC 805, and concluded that the amendment represented a modification to the RM2 Sublicense Agreement, whereby the Company did not reacquire any incremental rights or assets. Accordingly, the Company will continue to account for the RM2 Sublicense Agreement as an asset acquisition, separate from the LMI Acquisition.

20. Segment Information

The Company operates asone business segment. The results of this operating segment are regularly reviewed by the Company’s chief operating decision maker (“CODM”), the Chief Executive Officer. The CODM does not manage any part of the Company separately, and the allocation of resources and assessment of performance are based on the Company’s consolidated operating results. In order to evaluate thereportable segment’s performance, the CODM uses net income and gross margin based on the consolidated statements of operations. The CODM uses net income to monitor budget and forecast versus actual results in assessing segment performance and to evaluate income generated from segment assets in deciding how to allocate resources. The measure of segment assets is reported on the consolidated balance sheets as total consolidated assets.

Significant segment expenses reviewed by the CODM on a monthly basis include sales and marketing, general and administrative and R&D expenses as reported in the Company’s consolidated statements of operations. However, the CODM reviews R&D expenses in more detail for certain expenses related to the Company’s development of new products and clinical programs. The approximate disaggregated amounts that comprise R&D expenses regularly reviewed by the CODM are as follows:

(1)

Other R&D expenses consist of all other R&D costs incurred for the benefit of multiple R&D programs, including legal, employee costs, depreciation, information technology, other facility-bases expenses and other third-party costs.

Geographic Information

See Note 3,“Revenue from Contracts with Customers”for a disaggregation of revenue by geographic region. Long-lived assets by geographic region, which are based on asset location, are not presented because it is impracticable to do so.

21. Subsequent Events

On January 1, 2026, the Company completed the sale of its SPECT business to SHINE, a wholly-owned subsidiary of Illuminated Holdings, Inc. The Company is entitled to receive total consideration of up to $155.0 million, consisting of cash, a convertible installment note, a term note and contingent earnout payments. Under the terms of the definitive agreement, SHINE acquired the assets and liabilities associated with the SPECT business, including its approved products (TechneLite, NEUROLITE, Xenon Xe-133 Gas, and Cardiolite), the portion of the North Billerica, Massachusetts campus that manufactured the SPECT products and the SPECT-related Canadian operations. The Company expects to recognize a gain on sale of its SPECT business in the first quarter of 2026. See Note 8,“Assets and Liabilities Held for Sale”for more information on the sale of the Company’s SPECT business.

Strategic Program

On February 19, 2026, the Board approved a strategic program to simplify and streamline the Company’s operations so it can focus mainly on its radiodiagnostic business and pursue value-maximizing alternatives for its radiotherapeutic assets. As a result of the program, the Company expects to incur charges in 2026. The Company is unable to quantify the amount of such charges at this time.