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BASIS OF PRESENTATION, PRINCIPLES OF CONSOLIDATION USE OF ESTIMATES AND RECENT ACCOUNTING PRONOUNCEMENTS (Policies) | 9 Months Ended
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Sep. 30, 2025
Accounting Policies [Abstract] |
Basis of Presentation | Basis of Presentation The terms “Geron”, the “Company”, “we” and “us” as used in this Report refer to Geron Corporation and its wholly-owned subsidiaries, Geron UK Limited, or Geron UK, a United Kingdom company, and Geron Netherlands B.V., or Geron Netherlands, a Netherlands company. Geron UK was incorporated in September 2021, and its operations commenced in January 2022. Geron Netherlands was incorporated in February 2023, and its operations commenced in June 2023. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by United States, or U.S., generally accepted accounting principles, or GAAP, for complete financial statements. In the opinion of management, all adjustments considered necessary for a fair presentation have been included. Operating results for the three and nine months ended September 30, 2025 are not necessarily indicative of the results that may be expected for the year ending December 31, 2025 or any other period. These unaudited condensed consolidated financial statements and notes should be read in conjunction with the audited financial statements for each of the three years ended December 31, 2024, included in our Annual Report on Form 10-K for the year ended December 31, 2024, or the 2024 Form 10-K. The accompanying condensed consolidated balance sheet as of December 31, 2024 has been derived from audited financial statements at that date.
Principles of Consolidation | Principles of Consolidation The unaudited condensed consolidated financial statements include the accounts of Geron Corporation and its wholly-owned subsidiaries, Geron UK and Geron Netherlands. For Geron UK and Geron Netherlands, we have eliminated intercompany accounts and transactions. We prepare the financial statements of Geron UK and Geron Netherlands using the local currency as the functional currency. We translate the assets and liabilities of Geron UK and Geron Netherlands at rates of exchange at the balance sheet date and translate income and expense items at average monthly rates of exchange. The resultant translation adjustments are included in accumulated other comprehensive income (loss), a separate component of stockholders’ equity, on our condensed consolidated balance sheets.
Use of Estimates | Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, we evaluate our estimates, including those related to accrued liabilities, revenue recognition, fair value of marketable securities and equity investments, liabilities related to the sale of future royalties, operating leases, right-of-use assets, lease liabilities, inventory valuation, income taxes, and stock-based compensation. We base our estimates on historical experience and on various other market specific and relevant assumptions that we believe to be reasonable under the circumstances. Actual results could differ from those estimates.
Summary of Significant Accounting Policies | Summary of Significant Accounting Policies The significant accounting policies used in preparation of these condensed consolidated financial statements for the three and nine months ended September 30, 2025 are consistent with those discussed in Note 1 to the consolidated financial statements in the 2024 Form 10-K.
Recent Accounting Pronouncements | Recent Accounting Pronouncements New Accounting Pronouncements – Issued But Not Yet Adopted In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses. The amendments in ASU 2024-03 address investor requests for more detailed expense information and require additional disaggregated disclosures in the notes to financial statements for certain categories of expenses that are included on the face of the income statement. This guidance is effective for fiscal years beginning after December 15, 2026, and interim periods within fiscal years beginning after December 15, 2027, with early adoption permitted. We are evaluating the impact of this ASU on our condensed consolidated financial statements. Other recent accounting pronouncements issued by the FASB are not believed by management to have a material impact on our financial statements.

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