Summary of Significant Accounting Policies	9 Months Ended
Sep. 30, 2024
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Basis of Presentation and Consolidation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (U.S. GAAP) for interim financial information and the related rules and regulations of the Securities and Exchange Commission (SEC). Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for complete financial statements. In the Company’s opinion, all adjustments (consisting only of normal recurring adjustments) considered necessary for a fair statement of the results of operations and cash flows for the periods presented have been included. Operating results for the three and nine months ended September 30, 2024 are not necessarily indicative of the results that may be expected for the year ending December 31, 2024 or for any future period. The balance sheet as of December 31, 2023 has been derived from audited consolidated financial statements at that date but does not include all of the information required by U.S. GAAP for complete financial statements. The accompanying unaudited condensed consolidated financial statements and related financial information should be read in conjunction with the audited consolidated financial statements and the related notes thereto as of and for the year ended December 31, 2023 included in the Company’s Annual Report on Form 10-K filed with the SEC on February 28, 2024. There have been no significant changes to our accounting policies as described in Note 2, Summary of significant accounting policies, in the notes to the audited consolidated financial statements in Item 8 of Part II of the Form 10-K. The accompanying condensed consolidated financial statements include the accounts of Arcellx, Inc. and its wholly-owned subsidiary. All intercompany balances and transactions have been eliminated in consolidation. Recent Accounting Pronouncements In November 2023, the FASB issued ASU No.2023-07 "Improvements to Reportable Segment Disclosures" which requires an enhanced disclosure of significant segment expenses on an annual and interim basis. This guidance will be effective for the annual periods beginning the year ended December 31, 2024, and for interim periods beginning January 1, 2025. Early adoption is permitted. Upon adoption, the guidance should be applied retrospectively to all prior periods presented in the financial statements. The Company does not expect the adoption of this guidance to have a material impact on its consolidated financial statements. In December 2023, the FASB issued ASU No.2023-09 "Improvements to Income Tax Disclosures" which requires incremental annual disclosures around income tax rate reconciliation, income taxes paid and other related disclosures. This guidance requires prospective application and permits retrospective application to prior periods presented. The Company plans to adopt it beginning with its 2025 annual report to be filed in early 2026. The Company is currently evaluating the impact of the new guidance on its consolidated financial statements.

Summary of Significant Accounting Policies

9 Months Ended

Sep. 30, 2024

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

Basis of Presentation and Consolidation

The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (U.S. GAAP) for interim financial information and the related rules and regulations of the Securities and Exchange Commission (SEC). Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for complete financial statements. In the Company’s opinion, all adjustments (consisting only of normal recurring adjustments) considered necessary for a fair statement of the results of operations and cash flows for the periods presented have been included.

Operating results for the three and nine months ended September 30, 2024 are not necessarily indicative of the results that may be expected for the year ending December 31, 2024 or for any future period. The balance sheet as of December 31, 2023 has been derived from audited consolidated financial statements at that date but does not include all of the information required by U.S. GAAP for complete financial statements.

The accompanying unaudited condensed consolidated financial statements and related financial information should be read in conjunction with the audited consolidated financial statements and the related notes thereto as of and for the year ended December 31, 2023 included in the Company’s Annual Report on Form 10-K filed with the SEC on February 28, 2024. There have been no significant changes to our accounting policies as described in Note 2, Summary of significant accounting policies, in the notes to the audited consolidated financial statements in Item 8 of Part II of the Form 10-K.

The accompanying condensed consolidated financial statements include the accounts of Arcellx, Inc. and its wholly-owned subsidiary. All intercompany balances and transactions have been eliminated in consolidation.

Recent Accounting Pronouncements

In November 2023, the FASB issued ASU No.2023-07 "Improvements to Reportable Segment Disclosures" which requires an enhanced disclosure of significant segment expenses on an annual and interim basis. This guidance will be effective for the annual periods beginning the year ended December 31, 2024, and for interim periods beginning January 1, 2025. Early adoption is permitted. Upon adoption, the guidance should be applied retrospectively to all prior periods presented in the financial statements. The Company does not expect the adoption of this guidance to have a material impact on its consolidated financial statements.

In December 2023, the FASB issued ASU No.2023-09 "Improvements to Income Tax Disclosures" which requires incremental annual disclosures around income tax rate reconciliation, income taxes paid and other related disclosures. This guidance requires prospective application and permits retrospective application to prior periods presented. The Company plans to adopt it beginning with its 2025 annual report to be filed in early 2026. The Company is currently evaluating the impact of the new guidance on its consolidated financial statements.