Caribou Biosciences, Inc. 10-K

Item 9A. Controls and Procedures. Evaluation of Disclosure Controls and Procedures We have established disclosure controls and procedures designed to ensure that information required to be disclosed in the reports that we file or submit under the Exchange Act is recorded, processed, summarized, and reported within the time periods specified in SEC rules and forms and is accumulated and communicated to management, including the principal executive officer (our president and chief executive officer) and principal financial officer (our chief financial officer), to allow timely decisions regarding required disclosure. Our management, under the supervision and with the participation of our president and chief executive officer and chief financial officer, has evaluated the effectiveness of our disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act) as of the end of the period covered by this Annual Report on Form 10-K. Management recognizes that any disclosure controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving their objectives. Our disclosure controls and procedures have been designed to provide reasonable assurance of achieving their objectives. In addition, the design of disclosure controls and procedures must reflect the fact that there are resource constraints and that management is required to apply judgment in evaluating the benefits of possible controls and procedures relative to their costs. Based on such evaluation, our president and chief executive officer (principal executive officer) and our chief financial officer (principal financial officer) have concluded that our disclosure controls and procedures were effective at the reasonable assurance level as of December 31, 2023. Management’s Annual Report on Internal Control Over Financial Reporting Our management is responsible for establishing and maintaining adequate internal control over financial reporting as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act. Our internal control over financial reporting is a 122 Table of Contents process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with U.S. GAAP. Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate. Our management assessed the effectiveness of our internal control over financial reporting as of December 31, 2023 based on the criteria set forth by the Committee of Sponsoring Organizations of the Treadway Commission in its 2013 Internal Control - Integrated Framework. Based on this assessment, our management has concluded that our internal control over financial reporting was effective as of December 31, 2023. Attestation Report of the Registered Public Accounting Firm Our independent registered accounting firm is not required to opine on the effectiveness of our internal control over financial reporting pursuant to Section 404 of Sarbanes-Oxley Act of 2002 until we are no longer either an “emerging growth company” as defined in the JOBS Act or a smaller reporting company as defined by Rule 12b-2 of the Exchange Act that does not otherwise also qualify as an “accelerated filer” or “large accelerated filer” for SEC reporting purposes. Changes in Internal Control There were no changes in our internal control over financial reporting identified in management’s evaluation pursuant to Rules 13a-15(f) or 15d-15(f) of the Exchange Act during our fourth fiscal quarter ended December 31, 2023 that materially affected, or are reasonably likely to materially affect, our internal control over financial reporting. Item 9B. Other Information. (a) Not applicable. (b) During the quarter ended December 31, 2023, no director or Section 16 officer adopted or terminated any Rule 10b5-1 trading arrangement or non-Rule 10b5-1 trading arrangement. Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections. Not applicable. 123 Table of Contents PART III Certain information required by Part III is incorporated by reference herein to our definitive proxy statement for our 2024 Annual Meeting of Stockholders (“2024 Proxy Statement”) pursuant to Regulation 14A of the Securities Exchange Act of 1934, as amended (“Exchange Act”), which we intend to file not later than 120 days after the end of the fiscal year covered by this Annual Report on Form 10-K. Item 10. Directors, Executive Officers and Corporate Governance. The information required by this item of Form 10-K will be included under the caption “Board of Directors and Corporate Governance” and subsections thereof, including “—Nominees for Election as Class III Directors,” “—Directors Continuing in Office,” “—Family Relationships,” “—Classified Board of Directors,” and “—Board Committees—Audit Committee,” and under the caption “Executive Officers” in our 2024 Proxy Statement and is incorporated by reference herein. We have adopted a written Code of Business Conduct, Scientific and Data Integrity, and Ethics (“Code of Conduct”) that applies to all of our employees, consultants, contractors, and directors. A current copy of the Code of Conduct is available on the Corporate Governance section of our website, https://investor.cariboubio.com. The audit committee of our board of directors is responsible for overseeing the Code of Conduct and must approve any waivers of the Code of Conduct for our executive officers and directors. We expect that any amendments to the Code of Conduct, or any waivers of its requirements with respect to our executive officers and directors, will be disclosed on our website at the address indicated above. Our website and the information contained therein or connected thereto shall not be deemed to be incorporated into this Annual Report on Form 10-K. We have included our website address as an inactive textual reference only. We will provide to any person, without charge, a copy of the Code of Conduct. Any such request should be directed to Caribou Biosciences, Inc., 2929 7th Street, Suite 105, Berkeley, CA 94710, Attn: Chief Legal Officer and Corporate Secretary, telephone: 510-982-6030. Item 11. Executive Compensation. The information required by this item of Form 10-K will be included under the caption “Executive and Director Compensation” in our 2024 Proxy Statement and is incorporated by reference herein. Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters. The information required by this item of Form 10-K will be included under the captions “Security Ownership of Certain Beneficial Owners and Management” and “Securities Authorized for Issuance Under Equity Compensation Plans” in our 2024 Proxy Statement and is incorporated by reference herein. Item 13. Certain Relationships and Related Transactions, and Director Independence. The information required by this item of Form 10-K will be included under the captions “Certain Relationships and Related Party Transactions” and “Board of Directors and Corporate Governance—Director Independence” in our 2024 Proxy Statement and is incorporated by reference herein. Item 14. Principal Accounting Fees and Services. The information required by this item of Form 10-K will be included under the caption “Proposal No. 2 - Ratification of Selection of Independent Registered Public Accounting Firm” in our 2024 Proxy Statement and is incorporated by reference herein. 124 Table of Contents PART IV Item 15. Exhibits, Financial Statement Schedules. (a) The following documents are included in this Annual Report on Form 10-K: 1. The following Report and Consolidated Financial Statements of our company are included in this Annual Report on Form 10-K: Report of Independent Registered Public Accounting Firm (PCAOB ID No. 34) Consolidated Balance Sheets Consolidated Statements of Operations and Comprehensive Loss Consolidated Statements of Stockholders’ Equity Consolidated Statements of Cash Flows Notes to Consolidated Financial Statements See Index to Consolidated Financial Statements on page F-1 of this Annual Report on Form 10-K, incorporated into this item by reference. 2. All financial schedules have been omitted because the required information is either presented in the consolidated financial statements or the notes thereto or is not applicable or required. 3. The exhibits required by Item 601 of Regulation S-K and Item 15(b) of this Annual Report on Form 10-K are listed in the Exhibit Index immediately preceding the signature page of this Annual Report on Form 10-K. The exhibits listed in the Exhibit Index are incorporated by reference herein. Item 16. Form 10-K Summary. Not applicable. EXHIBIT INDEX Exhibit Number Exhibit Description 3.1 Amended and Restated Certificate of Incorporation of the Registrant (incorporated by reference to Exhibit 3.1 of the Registrant’s Current Report on Form 8-K (File No. 001-40631), filed with the SEC on July 28, 2021) 3.2 Amended and Restated Bylaws of the Registrant (incorporated by reference to Exhibit 3.2 of the Registrant’s Current Report on Form 8-K (File No. 001-40631), filed with the SEC on July 28, 2021) 4.1 Description of Common Stock (incorporated by reference to Exhibit 4.1 of the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2021 (File No. 001-40631) , filed with the SEC on March 21, 2022) 10.1 † Exclusive License Agreement, dated November 13, 2020, by and between the Registrant and Memorial Sloan Kettering Cancer Center (incorporated by reference to Exhibit 10.2 of the Form S-1) filed by the Registrant on July 1, 2021 (File No. 333-257604) (the “Form S-1”) 10.2† Sale and Assignment Agreement, dated January 31, 2020, by and between the Registrant and ProMab Biotechnologies, Inc. (incorporated by reference to Exhibit 10.3 of the Form S-1) 10.3† Amendment No. 1 to Sale and Assignment Agreement, dated October 20, 2020, by and between the Registrant and ProMab Biotechnologies, Inc. (incorporated by reference to Exhibit 10.4 of the Form S-1) 125 Table of Contents 10.4† Amendment No. 2 to Sale and Assignment Agreement, dated December 15, 2020, by and between the Registrant and ProMab Biotechnologies, Inc. (incorporated by reference to Exhibit 10.5 of the Form S-1) 10.5 Amendment No. 3 to Sale and Assignment Agreement, dated May 5, 2020, by and between the Registrant and ProMab Biotechnologies, Inc. (incorporated by reference to Exhibit 10.6 of the Form S-1) 10.6† Amended and Restated Collaboration and License Agreement, dated July 13, 2015, by and between the Registrant and Pioneer Hi-Bred International, Inc. (incorporated by reference to Exhibit 10.7 of the Form S-1) 10.7† Amendment No. 1 to Amended and Restated Collaboration and License Agreement, dated January 21, 2016, by and between the Registrant and Pioneer Hi-Bred International, Inc. (incorporated by reference to Exhibit 10.8 of the Form S-1) 10.8† Amendment No. 2 to Amended and Restated Collaboration and License Agreement, dated July 18, 2016, by and between the Registrant and Pioneer Hi-Bred International, Inc. (incorporated by reference to Exhibit 10.9 of the Form S-1) 10.9† Amendment No. 3 to Amended and Restated Collaboration and License Agreement, dated March 13, 2017, by and between the Registrant and Pioneer Hi-Bred International, Inc. (incorporated by reference to Exhibit 10.10 of the Form S-1) 10.10† Amendment No. 4 to Amended and Restated Collaboration and License Agreement, dated June 26, 2017, by and between the Registrant and Pioneer Hi-Bred International, Inc. (incorporated by reference to Exhibit 10.11 of the Form S-1) 10.11† Amendment No. 5 to Amended and Restated Collaboration and License Agreement, dated May 25, 2018, by and between the Registrant and Pioneer Hi-Bred International, Inc. (incorporated by reference to Exhibit 10.12 of the Form S-1) 10.12† Amendment No. 6 to Amended and Restated Collaboration and License Agreement, dated June 2, 2019, by and between the Registrant and Pioneer Hi-Bred International, Inc. (incorporated by reference to Exhibit 10.13 of the Form S-1) 10.13† Amendment No. 7 to Amended and Restated Collaboration and License Agreement, dated December 18, 2020, by and between the Registrant and Pioneer Hi-Bred International, Inc. (incorporated by reference to Exhibit 10.14 of the Form S-1) 10.14† Amendment No. 8 to Amended and Restated Collaboration and License Agreement, dated December 18, 2020, by and between the Registrant and Pioneer Hi-Bred International, Inc. (incorporated by reference to Exhibit 10.15 of the Form S-1) 10.15† License Agreement, dated July 16, 2014, by and between the Registrant and Intellia, LLC (incorporated by reference to Exhibit 10.16 of the Form S-1) 10.16† Amendment No. 1 to the License Agreement, dated February 2, 2016, by and between the Registrant and Intellia Therapeutics, Inc. as successor in interest to Intellia, LLC (incorporated by reference to Exhibit 10.17 of the Form S-1) 10.17† Addendum to License Agreement, dated February 2, 2016, by and between the Registrant and Intellia Therapeutics, Inc. as successor in interest to Intellia, LLC (incorporated by reference to Exhibit 10.18 of the Form S-1) 10.18† Leaseback Agreement, dated June 16, 2021, by and between the Registrant and Intellia Therapeutics, Inc. (incorporated by reference to Exhibit 10.19 of Amendment No. 1 to Form S-1 registration statement filed by the Registrant on July 19, 2021 (File No. 333-257604) 10.19† Consent to Assignments, Licensing and Common Ownership and Invention Management Agreement for a Programmable DNA Restriction Enzyme for Genome Editing, dated December 15, 2016, by and among the Registrant and the other parties thereto (incorporated by reference to Exhibit 10.20 of the Form S-1) 10.20† Exclusive License Agreement, dated April 16, 2013, by and among the Registrant, The Regents of the University of California, and the University of Vienna (incorporated by reference to Exhibit 10.21 of the Form S-1) 10.21† Amendment No. 1 to the Exclusive License Agreement, dated April 16, 2013, by and among the Registrant, The Regents of the University of California, and the University of Vienna (incorporated by reference to Exhibit 10.22 of the Form S-1) 126 Table of Contents 10.22† Amendment No. 2 to the Exclusive License Agreement, dated April 17, 2013, by and among the Registrant, The Regents of the University of California, and the University of Vienna (incorporated by reference to Exhibit 10.23 of the Form S-1) 10.23† Amendment No. 3 to the Exclusive License Agreement, dated April 16, 2021, by and among the Registrant, The Regents of the University of California, and the University of Vienna (incorporated by reference to Exhibit 10.24 of the Form S-1) 10.24† Memorandum of Understanding, dated March 14, 2019, by and among the Registrant, the University of Vienna, and the Regents of the University of California (incorporated by reference to Exhibit 10.25 of the Form S-1) 10.25 Amended and Restated Office/Laboratory Lease, dated March 31, 2021, by and between the Registrant and 2929 Seventh St., LLC (incorporated by reference to Exhibit 10.26 of the Form S-1) 10.26 First Amendment, dated January 11, 2022, to Amended and Restated Office/Laboratory Lease by and between Registrant and 2929 Seventh St., LLC (incorporated by reference to Exhibit 10.27 of the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2021 (File No. 001-40631) , filed with the SEC on March 21, 2022) 10.27 Office/Laboratory Lease between the Registrant and 7 th Street Property III General Partnership, having a commencement date of January 13, 2022 (incorporated by reference to Exhibit 10.1 of the Form 8-K (File No. 001-40631) filed by the Registrant on January 19, 2022) 10.28 Rider 1 to Office/Laboratory Lease between the Registrant and 7 th Street Property III General Partnership, effective as of the lease commencement date of January 13, 2022 (incorporated by reference to Exhibit 10.29 of the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2021 (File No. 001-40631) , filed with the SEC on March 21, 2022) 10.29+ Officer Employment Agreement by and between the Registrant and Rachel E. Haurwitz, Ph.D., dated July 27, 2021 (incorporated by reference to Exhibit 10.1 of the Form 8-K (File No. 001-40631) filed by the Registrant on July 28, 2021) 10.30+† Compensation Letter, dated February 11, 2022, from the Registrant to Rachel E. Haurwitz, Ph.D. (incorporated by reference to Exhibit 10.31 of the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2021 (File No. 001-40631) , filed with the SEC on March 21, 2022) 10.31+ Compensation Letter, dated February 16, 2023, from the Registrant to Rachel E. Haurwitz, Ph.D . (incorporated by reference to Exhibit 10. 34 of the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2022 (File No. 001-40631), filed with the SEC on March 9, 2023) 10.32+* Compensation Letter, dated February 20, 2024 , from the Registrant to Rachel E. Haurwitz, Ph.D. 10.33+ Officer Employment Agreement by and between the Registrant and Jason V. O’Byrne, dated July 27, 2021 (incorporated by reference to Exhibit 10.4 of the Form 8-K (File No. 001-40631) filed by the Registrant on July 28, 2021) 10.34+† Offer Letter between the Registrant and Jason V. O'Byrne, dated January 5, 2021 (incorporated by reference to Exhibit 10.33 of the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2021 (File No. 001-40631) , filed with the SEC on March 21, 2022) 10.35+† Compensation Letter, dated February 11, 2022, from the Registrant to Jason V. O’Byrne (incorporated by reference to Exhibit 10.34 of the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2021 (File No. 001-40631) , filed with the SEC on March 21, 2022) 10.36+ Compensation Letter, dated February 16, 2023, from the Registrant to Jason V. O’Byrne (incorporated by reference to Exhibit 10. 38 of the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2022 (File No. 001-40631), filed with the SEC on March 9, 2023) 10.37+* Compensation Letter, dated February 20, 2024, from the Registrant to Jason V. O’Byrne 10.38+ Officer Employment Agreement by and between the Registrant and Barbara G. McClung, J.D., dated July 27, 2021 (incorporated by reference to Exhibit 10.3 of the Form 8-K (File No. 001-40631) filed by the Registrant on July 28, 2021) 127 Table of Contents 10.39+† Compensation Letter, dated February 11, 2022, from the Registrant to Barbara G. McClung, J.D. (incorporated by reference to Exhibit 10.36 of the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2021 (File No. 001-40631) , filed with the SEC on March 21, 2022) 10.40+ Compensation Letter, dated February 16, 2023, from the Registrant to Barbara G. McClung, J.D. (incorporated by reference to Exhibit 10. 41 of the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2022 (File No. 001-40631), filed with the SEC on March 9, 2023) 10.41+* Compensation Letter, dated February 20, 2024, from the Registrant to Barbara G. McClung, J.D. 10.42+ Officer Employment Agreement by and between the Registrant and Steven B. Kanner, Ph.D., dated July 27, 2021 (incorporated by reference to Exhibit 10.2 of the Form 8-K (File No. 001-40631) filed by the Registrant on July 28, 2021) 10.43+† Compensation Letter, dated February 11, 2022, from the Registrant to Steven B. Kanner, Ph.D. (incorporated by reference to Exhibit 10.38 of the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2021 (File No. 001-40631) , filed with the SEC on March 21, 2022) 10.44+ Compensation Letter, dated February 16, 2023, from the Registrant to Steven B. Kanner, Ph.D. (incorporated by reference to Exhibit 10. 44 of the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2022 (File No. 001- 40631), filed with the SEC on March 9, 2023) 10.45+* Compensation Letter, dated February 20, 2024, from the Registrant to Steven B. Kanner, Ph.D. 10.46+ Officer Employment Agreement by and between the Registrant and Ruhi Khan, dated November 8, 2021 (incorporated by reference to Exhibit 10.39 of the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2021 (File No. 001-40631) , filed with the SEC on March 21, 2022) 10.47+† Compensation Letter, dated February 11, 2022, from the Registrant to Ruhi Khan (incorporated by reference to Exhibit 10.4 6 of the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 202 2 (File No. 001-40631), filed with the SEC on March 9 , 202 3 ) 10.48+ Compensation Letter, dated February 16, 2023, from the Registrant to Ruhi Khan (incorporated by reference to Exhibit 10. 47 of the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2022 (File No. 001-40631), filed with the SEC on March 9, 2023) 10.49+* Compensation Letter, dated February 20, 2024, from the Registrant to Ruhi Khan 10.50+† Offer Letter, dated October 29, 2021, between the Registrant and Syed Rizvi, M.D. (incorporated by reference to Exhibit 10.41 of the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2021 (File No. 001-40631) , filed with the SEC on March 21, 2022) 10.51+ Officer Employment Agreement by and between the Registrant and Syed Rizvi, M.D., dated January 18, 2022 (incorporated by reference to Exhibit 10.42 of the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2021 (File No. 001-40631) , filed with the SEC on March 21, 2022) 10.52+† Compensation Letter, dated February 16, 2023, from the Registrant to Syed Rizvi, M.D. (incorporated by reference to Exhibit 10. 50 of the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2022 (File No. 001-40631), filed with the SEC on March 9, 2023) 10.53+†* Separation Letter, dated December 19, 2023, between the Registrant and Syed Rizvi, M.D. 10.54+ Offer Letter, dated November 22 , 2023 , between the Registrant and T im Kelly 10.55+ Officer Employment Agreement by and between the Registrant and Tim Kelly , dated Januar y 1 , 2024 10.56+ 2013 Equity Incentive Plan (as originally adopted) (incorporated by reference to Exhibit 99.1 of the Form S-8 filed by the Registrant on July 26, 2021 (File No.: 333-258173) (the “Form S-8”)) 10.57+ 2013 Equity Incentive Plan (as amended May 12, 2016) (incorporated by reference to Exhibit 99.2 of the Form S-8) 10.58+ 2013 Equity Incentive Plan of the Registrant, as amended and restated April 3, 2019 and as amended March 1, 2021 (incorporated by reference to Exhibit 10.41 of Amendment No. 1 to Form S-1 registration statement filed by the Registrant on July 19, 2021 (File No. 333-257604)) 128 Table of Contents 10.59+ Amendment to 2013 Equity Incentive Plan (effective December 9, 2021) (incorporated by reference to Exhibit 10.46 of the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2021 (File No.: 333-258173) , filed with the SEC on March 21, 2022) 10.60+ Form of Stock Option Agreement under the 2013 Equity Incentive Plan (as originally adopted and as amended May 12, 2016) (incorporated by reference to Exhibit 99.4 of the Form S-8) 10.61+ Form of Stock Option Agreement under the 2013 Equity Incentive Plan, as amended and restated April 3, 2019 (incorporated by reference to Exhibit 10.1 of the Registrant’s Quarterly Report on Form 10-Q for the period ended September 30, 2021 (File No.: 333-258173) , filed by the Registrant on November 11, 2021) 10.62+ 2021 Equity Incentive Plan of the Registrant (incorporated by reference to Exhibit 99.6 of the Form S-8) 10.63+ Form of Employee Stock Option Agreement under the 2021 Equity Incentive Plan of the Registrant (incorporated by reference to Exhibit 10.50 of the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2021 (File No.: 333-258173) , filed with the SEC on March 21, 2022) 10.64+ Form of Non-Employee Director Stock Option Agreement under the 2021 Equity Incentive Plan of the Registrant (incorporated by reference to Exhibit 10.51 of the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2021 (File No.: 333-258173) , filed with the SEC on March 21, 2022) 10.65+ Form of Restricted Stock Unit Award Grant Notice and Restricted Stock Unit Award Agreement under the 2021 Equity Incentive Plan of the Registrant (incorporated by reference to Exhibit 10.52 of the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2021 (File No.: 333-258173) , filed with the SEC on March 21, 2022) 10.66+ Form of Restricted Stock Unit Award Grant Notice and Restricted Stock Unit Award Agreement under the 2021 Equity Incentive Plan of the Registrant (incorporated by reference to Exhibit 10.1 of the Registrant’s Quarterly Report on Form 10-Q for the period ended September 30, 2022 (File No.: 333-258173) , filed by the Registrant on November 8, 2022) 10.67+ Form of Performance Stock Unit Award Grant Notice and Performance Stock Unit Award Agreement under the 2021 Equity Incentive Plan of the Registrant (incorporated by reference to Exhibit 10.2 of the Registrant’s Quarterly Report on Form 10-Q for the period ended September 30, 2022 (File No.: 333-258173) , filed by the Registrant on November 8, 2022) 10.68+ 2021 Employee Stock Purchase Plan (incorporated by reference to Exhibit 99.7 of the Form S-8) 10.69 Form of Indemnification Agreement between the Registrant and its directors and officers (incorporated by reference to Exhibit 10.50 of the Form S-1) 10.70 Open Market Sale Agreement SM , dated August 9, 2022, by and between the Registrant and Jefferies LLC (incorporated by reference to Exhibit 1.2 to the Company’s Registration Statement on Form S-3 (File No. 333-266712) filed with the SEC on August 9, 2022) 10.71 Securities Purchase Agreement, dated June 29, 2023, by and between the Registrant and Pfizer, Inc. (incorporated by reference to Exhibit 10.1 to the Form 8-K filed by the Registrant with the SEC on July 6, 2023) 10.72 Voting Agreement, dated June 29. 2023, by and between the Registrant and Pfizer, Inc. (incorporated by reference to Exhibit 10.2 to the Form 8-K filed by the Registrant with the SEC on July 6, 2023) 21.1* List of Subsidiaries of the Registrant 23.1* Consent of Deloitte & Touche LLP 31.1* Certification of Principal Executive Officer Pursuant to Rules 13a-14(a) and 15d-14(a) under the Exchange Act, as Adopted Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002. 31.2* Certification of Principal Financial Officer Pursuant to Rules 13a-14(a) and 15d-14(a) under the Exchange Act, as Adopted Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002. 32.1# Certification of Principal Executive Officer Pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002. 32.2# Certification of Principal Financial Officer Pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002. 97.1* C lawback Policy 129 Table of Contents 101.INS* Inline XBRL Instance Document – the instance document does not appear in the Interactive Data File because XBRL tags are embedded within the Inline XBRL document. 101.SCH* Inline XBRL Taxonomy Extension Schema Document 101.CAL* Inline XBRL Taxonomy Extension Calculation Linkbase Document 101.DEF* Inline XBRL Taxonomy Extension Definition Linkbase Document 101.LAB* Inline XBRL Taxonomy Extension Label Linkbase Document 101.PRE* Inline XBRL Taxonomy Extension Presentation Linkbase Document 104 Cover Page Interactive Data File (formatted as inline XBRL and contained in Exhibit 101) __________________________________ * Indicates filed herewith + Indicates management contract or compensatory plan † Indicates certain portions of this document that constitute confidential information have been redacted in accordance with Regulation S-K, Item 601(b)(10) # This certification is being furnished solely to accompany this Annual Report on Form 10-K pursuant to 18 U.S.C. Section 1350, and is not being filed for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (“Exchange Act”), or otherwise subject to the liability of that section, nor shall it be deemed incorporated by reference into any filing of the Registrant under the Securities Act of 1933, as amended, or the Exchange Act, whether made before or after the date hereof, regardless of any general incorporation language in such filing. 130 Table of Contents SIGNATURES Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this Annual Report on Form 10-K (this “Report”) to be signed on its behalf by the undersigned, thereunto duly authorized . CARIBOU BIOSCIENCES, INC. Date: March 11, 2024 By: /s/ Rachel E. Haurwitz Rachel E. Haurwitz President and Chief Executive Officer Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, this Report has been signed below by the following persons on behalf of the Registrant in the capacities and on the dates indicated. Name Title Date /s/ Rachel E. Haurwitz President and Chief Executive Officer ( Principal Executive Officer ); Director March 11, 2024 Rachel E. Haurwitz /s/ Jason V. O’Byrne Chief Financial Officer ( Principal Financial Officer & Principal Accounting Officer ) March 11, 2024 Jason V. O’Byrne /s/ Scott Braunstein Director March 11, 2024 Scott Braunstein /s/ Andrew Guggenhime Director March 11, 2024 Andrew Guggenhime /s/ Dara Richardson-Heron Director March 11, 2024 Dara Richardson-Heron /s/ David Johnson Director March 11, 2024 David Johnson /s/ Natalie R. Sacks Director March 11, 2024 Natalie R. Sacks /s/ Nancy Whiting Director March 11, 2024 Nancy Whiting /s/ Ran Zheng Director March 11, 2024 Ran Zheng 131 Table of Contents INDEX TO CONSOLIDATED FINANCIAL STATEMENTS Index to Audited Financial Statements as of and for the Years Ended December 31, 2023 and 2022: Report of Independent Registered Public Accounting Firm (PCAOB ID No. 34 ) F- 2 Consolidated Balance Sheets F- 3 Consolidated Statements of Operations and Comprehensive Loss F- 4 Consolidated Statements of Stockholders’ Equity F- 5 Consolidated Statements of Cash Flows F- 6 Notes to Consolidated Financial Statements F- 7 F-1 Table of Contents REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM To the stockholders and the Board of Directors of Caribou Biosciences, Inc. Opinion on the Financial Statements We have audited the accompanying consolidated balance sheets of Caribou Biosciences, Inc. and subsidiaries (the "Company") as of December 31, 2023 and 2022, the related consolidated statements of operations and comprehensive loss, stockholders' equity, and cash flows, for each of the two years in the period ended December 31, 2023, and the related notes (collectively referred to as the "financial statements"). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2023 and 2022, and the results of its operations and its cash flows for each of the two years in the period ended December 31, 2023, in conformity with accounting principles generally accepted in the United States of America. Basis for Opinion These financial statements are the responsibility of the Company's management. Our responsibility is to express an opinion on the Company's financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB. We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. The Company is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. As part of our audits, we are required to obtain an understanding of internal control over financial reporting but not for the purpose of expressing an opinion on the effectiveness of the Company’s internal control over financial reporting. Accordingly, we express no such opinion. Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion. /s/ Deloitte & Touche LLP San Francisco, California March 11, 2024 We have served as the Company's auditor since 2016. F-2 Table of Contents CARIBOU BIOSCIENCES, INC. AND ITS SUBSIDIARIES Consolidated Balance Sheets (in thousands, except share and per share amounts) December 31, 2023 December 31, 2022 ASSETS CURRENT ASSETS: Cash and cash equivalents $ 51,162 $ 58,338 Marketable securities, short-term 277,665 189,325 Accounts receivable 148 202 Contract assets 1,425 2,247 Other receivables 2,286 2,215 Prepaid expenses and other current assets 6,155 7,921 Total current assets 338,841 260,248 NON-CURRENT ASSETS Investments in equity securities 7,753 7,698 Marketable securities, long-term 43,577 69,373 Property and equipment, net 18,270 10,678 Operating lease, right of use assets 22,182 24,230 Other assets 1,586 1,538 TOTAL ASSETS $ 432,209 $ 373,765 LIABILITIES AND STOCKHOLDERS’ EQUITY CURRENT LIABILITIES: Accounts payable $ 3,120 $ 1,146 Accrued expenses and other current liabilities 21,135 16,079 Operating lease liabilities, current 1,200 966 Deferred revenue ($ 2,487 and $ 150 from related party, respectively) 2,847 9,937 Total current liabilities 28,302 28,128 LONG-TERM LIABILITIES Deferred revenue, net of current portion ($ 3,730 and $ 0 from related party, respectively) 6,102 15,954 MSKCC success payments liability 2,939 1,651 Operating lease liabilities, non-current 25,908 26,780 Deferred tax liabilities 557 381 Total liabilities 63,808 72,894 COMMITMENTS AND CONTINGENCIES (Note 9) STOCKHOLDERS’ EQUITY Common stock, par value $ 0.0001 per share, 300,000,000 shares authorized at December 31, 2023 and 2022, respectively; 88,448,948 and 61,029,184 shares issued and outstanding at December 31, 2023 and 2022, respectively 8 6 Additional paid-in-capital 667,648 499,598 Accumulated other comprehensive income (loss) 30 ( 1,518 ) Accumulated deficit ( 299,285 ) ( 197,215 ) Total stockholders’ equity 368,401 300,871 TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY $ 432,209 $ 373,765 The accompanying notes are an integral part of these consolidated financial statements. F-3 Table of Contents CARIBOU BIOSCIENCES, INC. AND ITS SUBSIDIARIES Consolidated Statements of Operations and Comprehensive Loss (in thousands, except share and per share amounts) Years Ended December 31, 2023 2022 Licensing and collaboration revenue (including $ 2,393 and $ 0 , from related parties) $ 34,477 $ 13,851 Operating expenses: Research and development 112,075 82,230 General and administrative 38,461 38,020 Total operating expenses 150,536 120,250 Loss from operations ( 116,059 ) ( 106,399 ) Other income (expense): Change in fair value of equity securities ( 6 ) ( 133 ) Change in fair value of the MSKCC success payments liability ( 1,288 ) 2,429 Other income, net 15,476 4,752 Total other income 14,182 7,048 Net loss before provision for income taxes ( 101,877 ) ( 99,351 ) Provision for income taxes 193 70 Net loss ( 102,070 ) ( 99,421 ) Other comprehensive income (loss): Net unrealized gain (loss) on available-for-sale marketable securities 1,548 ( 1,383 ) Net comprehensive loss $ ( 100,522 ) $ ( 100,804 ) Net loss per share, basic and diluted $ ( 1.38 ) $ ( 1.64 ) Weighted-average common shares outstanding, basic and diluted 73,807,597 60,801,133 The accompanying notes are an integral part of these consolidated financial statements. F-4 Table of Contents CARIBOU BIOSCIENCES, INC. AND ITS SUBSIDIARIES Consolidated Statements of Stockholders’ Equity (in thousands, except share amounts) Common Stock Additional Paid-In Capital Accumulated Other Comprehensive Income (Loss) Accumulated Deficit Total Stockholders’ Equity Shares Amount BALANCE—December 31, 2021 60,263,158 $ 6 $ 485,748 $ ( 135 ) $ ( 97,794 ) $ 387,825 Issuance of common stock upon employee stock plans 69,113 — 638 — — 638 Issuance of common stock on exercise of options 696,913 — 1,497 — — 1,497 Stock-based compensation expense — — 11,715 — — 11,715 Other comprehensive loss — — — ( 1,383 ) — ( 1,383 ) Net loss — — — — ( 99,421 ) ( 99,421 ) BALANCE—December 31, 2022 61,029,184 $ 6 $ 499,598 $ ( 1,518 ) $ ( 197,215 ) $ 300,871 Issuance of common stock under employee stock plans 138,454 — 787 — — 787 Issuance of common stock on exercise of options 228,264 — 793 — — 793 Issuance of common stock on RSU release 78,596 — — — — — Issuance of common stock in connection with public follow-on offering, net of offering expenses 22,115,384 2 134,423 — — 134,425 Issuance of common stock in connection with at-the-market offering, net of offering expenses 168,635 — 1,007 — — 1,007 Issuance of common stock pursuant to a private placement with Pfizer 4,690,431 — 17,290 — — 17,290 Stock-based compensation expense — — 13,750 — — 13,750 Other comprehensive income — — — 1,548 — 1,548 Net loss — — — — ( 102,070 ) ( 102,070 ) BALANCE—December 31, 2023 88,448,948 $ 8 $ 667,648 $ 30 $ ( 299,285 ) $ 368,401 The accompanying notes are an integral part of these consolidated financial statements. F-5 Table of Contents CARIBOU BIOSCIENCES, INC. AND ITS SUBSIDIARIES Consolidated Statements of Cash Flows (in thousands) Years Ended December 31, 2023 2022 CASH FLOWS FROM OPERATING ACTIVITIES: Net loss $ ( 102,070 ) $ ( 99,421 ) Adjustments to reconcile net loss to net cash used in operating activities: Depreciation and amortization 3,525 1,622 Gain on disposal of fixed assets ( 34 ) — Non-cash consideration for licensing and collaboration revenue ( 61 ) ( 205 ) Change in fair value of equity securities 6 133 Stock-based compensation expense 13,750 11,716 Change in fair value of MSKCC success payments liability 1,288 ( 2,429 ) Acquired in-process research and development — 600 Accretion of discounts on investments in marketable securities, net ( 4,425 ) ( 797 ) Non-cash lease expense 2,048 2,019 Changes in operating assets and liabilities: Accounts receivable 54 951 Contract assets 822 ( 759 ) Other receivables ( 71 ) 3,268 Prepaid expenses and other current assets 1,766 ( 975 ) Other assets ( 48 ) ( 564 ) Accounts payable 1,819 ( 2,721 ) Accrued expenses and other current liabilities 5,743 1,953 Deferred revenue, current and long-term ( 16,943 ) ( 4,844 ) Operating lease liabilities ( 637 ) ( 403 ) Other liabilities — ( 15 ) Deferred tax liabilities 177 ( 95 ) Net cash used in operating activities ( 93,291 ) ( 90,966 ) CASH FLOWS FROM INVESTING ACTIVITIES: Proceeds from sales and maturities of marketable securities 338,188 252,868 Purchases of marketable securities ( 394,758 ) ( 339,063 ) Purchases of property and equipment ( 11,613 ) ( 6,454 ) Payments to acquire in-process research and development — ( 600 ) Net cash used in investing activities ( 68,183 ) ( 93,249 ) CASH FLOWS FROM FINANCING ACTIVITIES: Proceeds from public follow-on public offering, net of offering expenses 134,423 — Proceeds from issuance of common stock in a private placement with Pfizer 17,290 — Proceeds from exercise of stock options and purchases of common stock under employee stock purchase plan 1,578 2,133 Proceeds from issuance of common stock related to at-the-market offering, net of offering expenses 1,007 — Net cash provided by financing activities 154,298 2,133 NET DECREASE IN CASH, CASH EQUIVALENTS, AND RESTRICTED CASH ( 7,176 ) ( 182,082 ) CASH, CASH EQUIVALENTS, AND RESTRICTED CASH — BEGINNING OF PERIOD 58,384 240,466 CASH, CASH EQUIVALENTS, AND RESTRICTED CASH — END OF PERIOD $ 51,208 $ 58,384 RECONCILIATION OF CASH, CASH EQUIVALENTS, AND RESTRICTED CASH Cash and cash equivalents $ 51,162 $ 58,338 Restricted cash 46 46 CASH, CASH EQUIVALENTS, AND RESTRICTED CASH ON THE BALANCE SHEET $ 51,208 $ 58,384 SUPPLEMENTAL CASH FLOW INFORMATION: Cash paid for income taxes $ 170 $ — SUPPLEMENTAL SCHEDULE OF NON-CASH INVESTING AND FINANCING ACTIVITIES: Purchases of property and equipment included in accounts payable and accrued expenses $ 692 $ 1,223 Right-of-use-assets obtained in exchange for new operating lease liabilities $ — $ 26,249 The accompanying notes are an integral part of these consolidated financial statements. F-6 Table of Contents CARIBOU BIOSCIENCES, INC. AND ITS SUBSIDIARIES Notes to Consolidated Financial Statements 1. Description of the Business, Organization, and Liquidity Business and Organization Caribou Biosciences, Inc. (“Company” or “we”) is a clinical-stage C lustered R egularly I nterspaced S hort P alindromic R epeats (“CRISPR”) genome-editing biopharmaceutical company dedicated to developing transformative therapies for patients with devastating diseases. Our genome-editing platform, including our novel chRDNA ( C RISPR h ybrid R NA- DNA , or “chRDNA,” pronounced “chardonnay”) technology, enables more precise genome editing to develop cell therapies that are armored to improve antitumor activity. We are advancing a pipeline of allogeneic, or off-the-shelf, cell therapies from our chimeric antigen receptor (“CAR”) T (“CAR-T”) cell and CAR-natural killer (“CAR-NK”) cell platforms as readily available therapeutic treatments for patients. We incorporated in October 2011 as a Delaware corporation and are headquartered in Berkeley, California. We have four wholly owned subsidiaries: Antler Holdco, LLC, incorporated in Delaware in April 2019; Microbe Holdco, LLC, incorporated in Delaware in June 2020; Arboreal Holdco, LLC, incorporated in Delaware in November 2020; and Biloba Holdco, LLC, incorporated in Delaware in April 2021. Our wholly owned subsidiaries hold interests in our equity investments and do not have operating activities. Liquidity We have incurred operating losses and negative cash flows from operations since our inception and we had an accumulated deficit of $ 299.3 million as of December 31, 2023. During the year ended December 31, 2023, we incurred a net loss of $ 102.1 million and used $ 93.3 million of cash in operating activities. We expect to continue to incur substantial losses, and our ability to achieve and sustain profitability will depend on the successful development, regulatory approval, and commercialization of our product candidates and on our generation of sufficient revenue to support our cost structure. We may never achieve profitability and, unless and until we do, we will need to continue to raise additional capital. Our management expects that existing cash, cash equivalents, and marketable securities of $ 372.4 million as of December 31, 2023, will be sufficient to fund our current operating plan for at least the next 12 months from the date of issuance of our consolidated financial statements. In July and August of 2023, we issued and sold a total of 22,115,384 shares of our common stock in an underwritten follow-on public offering for total net proceeds of approximately $ 134.4 million, which included the full exercise of the underwriters’ right to purchase 2,884,615 additional shares of our common stock. During the year ended December 31, 2023, we sold 168,635 shares of our common stock under the Open Market Sale Agreement SM (“ATM Sales Agreement”) with Jefferies LLC (“Jefferies”), at an average price per share of $ 7.32 for aggregate gross proceeds of $ 1.2 million ($ 1.0 million net of offering expenses). In February 2024, we sold 1,594,171 shares of our common stock under the ATM Sales Agreement, at an average price per share of $ 7.33 for aggregate gross proceeds of $ 11.7 million ($ 11.3 million, net of offering expenses). 2. Summary of Significant Accounting Policies Basis of Presentation and Principles of Consolidation The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”) and include our and the accounts of our wholly owned subsidiaries. All intercompany accounts and transactions are eliminated in consolidation. Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires our management to make estimates and assumptions that affect the reported amounts of assets and liabilities; the disclosure of contingent assets and liabilities at the date of our consolidated financial statements; and the reported amounts of revenue, income, and expenses during the applicable reporting period. On an ongoing basis, we evaluate our estimates and assumptions, including those related to revenue recognition, stock-based compensation expense, accrued expenses related to research F-7 Table of Contents and development activities, valuation of the Memorial Sloan Kettering Cancer Center (“MSKCC”) success payments liability, operating lease right-of-use assets and liabilities, and income taxes. Our management bases its estimates on historical experience and on various other assumptions that they believe to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ materially from those estimates. Segments We operate and manage our business as one reportable operating segment, which is the business of developing a pipeline of allogeneic CAR-T and CAR-NK cell therapies. Our president and chief executive officer, who is the chief operating decision maker, reviews financial information on an aggregate basis for allocating resources and evaluating financial performance. All long-lived assets are maintained in the United States. Concentrations of Credit Risk and Other Uncertainties Financial instruments that potentially subject us to concentration of credit risk consist of cash and cash equivalents, accounts receivable, contract assets, other receivables, and investments in marketable securities and equity securities. Substantially all of our cash and cash equivalents are deposited in accounts at three financial institutions, and our account balances exceed federally insured limits. We mitigate the risks by investing in high-grade instruments, limiting our exposure to one issuer, and we monitor the ongoing creditworthiness of the financial institutions and issuers. Licensees that represent 10% or more of our revenue and accounts receivable and contract assets were as follows: Revenue Accounts Receivable and Contract Assets Years Ended December 31, As of December 31, 2023 2022 2023 2022 Licensee A * 16.2 % 47.5 % 23.8 % Licensee B 71.9 % 57.4 % * 36.6 % Total 71.9 % 73.6 % 47.5 % 60.4 % *Less than 10% We monitor economic conditions to identify facts or circumstances that may indicate if any of our accounts receivable are not collectible or if the contract assets should be impaired. No allowance for credit losses or contract asset impairment was recorded as of December 31, 2023 or 2022. Revenue Recognition We determine whether agreements are within the scope of Accounting Standard Codification (“ASC”) Topic 606, Revenue from contracts with customers (“ASC 606”) or other topics at the effective date of an agreement. For agreements that are determined to be within the scope of ASC 606, revenue is recognized when a licensee, or customer, obtains control of promised goods or services (e.g., an intellectual property license). The amount of revenue recognized reflects the consideration that we expect to be entitled to receive in exchange for these goods and services. To achieve this core principle, we apply the following five steps (i) identify the contract with the customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when or as we satisfy a performance obligation. Our revenues are primarily derived through license and/or license and collaboration agreements. The terms of these types of agreements may include (i) licenses for our technology, (ii) research and development services, and (iii) services or obligations in connection with our participation in research or governance committees. Payments to us under these arrangements typically include one or more of the following: nonrefundable upfront license fees, maintenance fees, milestones, and other contingent payments to us for the achievement of defined collaboration objectives and certain preclinical, clinical, regulatory, and sales-based events, as well as royalties on sales of any commercialized products. F-8 Table of Contents We assess whether the promises in our contracts with third parties are considered distinct performance obligations that should be accounted for separately. Judgment is required to determine whether a license to our intellectual property is distinct from research and development services or participation on research or governance committees. If a license to intellectual property controlled by us is determined to be distinct from the other performance obligations identified in the agreement, we recognize revenues allocated to the license at the point in time when the license is transferred to the licensee and the licensee is able to use and benefit from the license. For licenses that are combined with other promises, we utilize our 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. We evaluate the measure of progress using the input method for each reporting period and, if necessary, adjust the measure of performance and related revenue recognition. Certain of our license agreements include contingent milestone payments. Such milestone payments are typically payable when the collaborator or licensee achieves certain predetermined clinical, regulatory, and/or commercial milestones. Milestone payments that are not within our control or the control of the licensee, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. At each reporting date, we reevaluate whether the milestones are considered probable of being reached, and we estimate the amount to be included in the transaction price by 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 in such period of determination. Our license and/or collaboration and license agreements may also include contingent payments related to sales-based milestones. Sales-based milestones are typically payable when annual sales of a covered product reach specified levels. Sales-based milestones are recognized at the later of when the associated performance obligation has been satisfied or when the sales occur. Unlike other contingency payments, such as regulatory milestones, sales-based milestones are not included in the transaction price based on estimates at the inception of the contract, but rather, are included when the sales or usage occur. We use the sales-based royalty exception because the license is a predominant item to which sales-based royalties relate. Certain of our license agreements have two performance obligations: a license and a material right for annual license renewals. Such license agreements require payments of non-refundable annual license fees by the licensee (referred to as maintenance fees in the license agreements), which are accounted for as material rights for license renewals. We recognize revenue when the license is delivered and the term commences. Revenue for the material right for license renewals is recognized at the point in time that the annual license fee is paid by the licensee and the renewal period begins. Payments received under third-party contracts are recorded as deferred revenue upon receipt or when due and may require deferral of revenue recognition to a future period until we satisfy our performance obligations under these contracts. We record contract assets when payment is due under third-party contracts conditioned on future performance or the occurrence of other events. Amounts payable to us are recorded as accounts receivable if invoiced and if our right to consideration is unconditional. Fair Value Measurements 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. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability (Note 3). Cash and Cash Equivalents We consider all highly liquid investments purchased with an original maturity of three months or less to be cash equivalents. As of December 31, 2023 and 2022, cash and cash equivalents consisted of cash, money market funds, commercial paper securities, and U.S. Treasury bills. Restricted Cash We define restricted cash as cash and cash equivalents that cannot be withdrawn or used for general operating activities. Our restricted cash consists of a letter of credit with a financial institution related to one of our workers’ compensation insurance policies. As of December 31, 2023 and 2022, we had less than $ 0.1 million of restricted cash, which was recorded in other assets in our consolidated balance sheets. F-9 Table of Contents Marketable Securities Our short-term and long-term marketable securities are available for sale securities and consist of U.S. Treasury bills, commercial paper, U.S. government agency bonds, and corporate debt securities. We classify those securities that mature in more than 12 months as long-term investments in the consolidated balance sheets. We record at estimated fair value based on quoted market prices or observable market inputs of almost identical assets, with the unrealized holding gains or losses recorded in other comprehensive loss in the consolidated statements of operations and comprehensive loss. The amortized cost of securities is adjusted for amortization of premiums and accretion of discounts to maturity, which are both recorded to interest income in the consolidated statements of operations and comprehensive loss. When the fair value of a debt security declines below its amortized cost basis, any portion of that decline attributable to credit losses, to the extent expected to be nonrecoverable before the sale of the security, is recognized in our statement of operations. When the fair value of a debt security declines below its amortized cost basis due to changes in interest rates, such amounts are recorded in other comprehensive loss, and are recognized in our statements of operations only if we sell or intend to sell the security before recovery of its cost basis. Investments in Equity Securities We may receive as consideration under our license agreements equity securities of private or public companies (an “investee”). If we determine that we do not have control over these investees under either the Variable Interest Entity (“VIE”) or voting models, we then determine if we have an ability to exercise significant influence via voting interests, board of director representation, or other business relationships. If we conclude that we do not have an ability to exercise significant influence over an investee, we account for our investment at fair value and may elect to account for an equity security without a readily determinable fair value using a measurement alternative. This measurement alternative allows us to measure the equity investment at its cost minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer. If we determine that we do have control over these companies under either voting or VIE models, we consolidate them in our consolidated financial statements. As of December 31, 2023 and 2022, investments in equity securities, long-term, consisted primarily of our investment in the preferred stock of a private company, related party (Note 7). We concluded that our shares of the private company’s preferred stock are not in substance common stock and, since these securities do not have readily determinable fair value, we account for our investment in the private company’s preferred stock using the measurement alternative method. As of December 31, 2023 and 2022, we did not recognize any impairment loss related to this investment. Property and Equipment Property and equipment are recorded at cost, net of accumulated depreciation and amortization. Property and equipment are depreciated using the straight-line method over the estimated useful lives of the assets. Computer equipment 3 years Furniture and office equipment 5 years Lab equipment 5 years Leasehold improvements Shorter of remaining lease term or estimated useful life Upon retirement or sale of the assets, the cost and related accumulated depreciation and amortization are removed from the balance sheet and the resulting gain or loss is recorded in the statements of operations. Repairs and maintenance are expensed as incurred. Impairment of Long-Lived Assets We evaluate the carrying amount of our long-lived assets whenever events or changes in circumstances indicate that the assets may not be recoverable. An impairment loss is recognized when estimated future cash flows expected to result from the use of the asset and its eventual disposition is less than the carrying amount of the asset. To date, there have been no such impairment losses. F-10 Table of Contents Leases Under Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) No. 2016-02, Leases (Topic 842) and its associated amendments, we determine if an arrangement is a lease at inception. In addition, we determine whether a lease meets the classification criteria of a finance or operating lease at the lease commencement date considering whether: (i) the lease transfers ownership of the underlying asset to the lessee at the end of the lease term; (ii) the lease grants the lessee an option to purchase the underlying asset that the lessee is reasonably certain to exercise; (iii) the lease term is for a major part of the remaining economic life of the underlying asset; (iv) the present value of the sum of the lease payments and residual value guaranteed by the lessee equals or exceeds substantially all of the fair value of the underlying asset; and (v) the underlying asset is such a specialized nature that it is expected to have no alternative use to the lessor at the end of the lease term. As of December 31, 2023, our leases consisted of real estate operating leases and we did not have any finance leases. Operating leases are included in Operating lease right-of-use assets; Operating lease liabilities, current; and Operating lease liabilities, non-current in our consolidated balance sheets. Right-of-use assets represent our right to use the underlying assets for the lease term and lease liabilities represent our obligation to make lease payments arising from the leases. Operating lease right-of-use assets and liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. In determining the present value of lease payments, if the rate implicit in the lease is not readily determinable, we would use our incremental borrowing rate based on the information available at the lease commencement date. We would determine the incremental borrowing rate based on an analysis of corporate bond yields with a credit rating similar to ours. The determination of our incremental borrowing rate requires management judgment, including development of a synthetic credit rating and cost of debt, as we currently do not carry any debt. We believe that the estimates used in determining the incremental borrowing rate are reasonable based upon facts and circumstances. Applying different judgments to the same facts and circumstances could yield a different incremental borrowing rate. The operating lease right-of-use assets also include adjustments for prepayments and accrued lease payments and exclude lease incentives. Right-of-use assets and lease liabilities may include options to extend or terminate leases if it is reasonably certain that we will exercise such options. Lease payments which are fixed and determinable are amortized as rent and lease expense on a straight-line basis over the expected lease term. Variable lease costs, which are dependent on usage, a rate or index, including common area maintenance charges, are expensed as incurred. Lease agreements that include lease and non-lease components are accounted for as a single lease component. Lease agreements with non-cancelable terms of less than 12 months are not recorded on our balance sheets. MSKCC Success Payments Liability Under the terms of our Exclusive License Agreement, dated November 13, 2020, with MSKCC (Note 4), we are obligated to make success payments and a change of control payment if our stock price increases by certain multiples of increasing value based on a comparison of the fair market value of our common stock with $ 5.1914 per share, adjusted for any future stock splits, during a specified time period. The relevant time period commences when the first patient is dosed with our first CLL-1 product candidate (CB-012) in the first phase 1 clinical trial and ends upon the earlier of the third anniversary of approval of our biologics license application (“BLA”) by the FDA or 10 years from the date the first patient was dosed with our first CLL-1 product candidate in the first phase 1 clinical trial. The success payments liability is accounted for under ASC 815, Derivatives and Hedging. The nature of the success payments liability is contingent consideration for the MSKCC exclusive license and, as such, it was accounted for as research and development expenses at estimated fair value at inception. The success payments liability is remeasured at fair value at each subsequent balance sheet date, and changes in the fair value of the success payments liability are included in other income (expense) in the consolidated statements of operations and comprehensive loss. To determine the estimated fair value of the MSKCC success payments liability, we use a Monte Carlo simulation methodology that models the future movement of stock prices based on several key variables. This model requires significant estimates and assumptions in determining the estimated fair value of the MSKCC success payments liability at each balance sheet date. The following variables were incorporated in the estimated fair value of the success payments liability: estimated term of the success payments, fair value of common stock, expected volatility, risk-free interest rate, and estimated number and timing of valuation measurement dates on the basis of which payments may be triggered. The computation of expected volatility was estimated using a combination of available information about the historical volatility of stocks of similar publicly traded companies for a period matching the expected term assumption and projected volatility. The assumptions used to calculate the fair value of the MSKCC success payments liability are subject to a significant amount of judgment including the expected volatility that was estimated using available information about the historical volatility of stocks of publicly traded companies that are similar to us, the estimated term, and the estimated F-11 Table of Contents number and timing of valuation measurement dates. There are several valuation measurement dates that may trigger payments under the MSKCC Agreement and are considered in our valuation of the MSKCC success payments liability (Note 4). Accrued Research and Development Expenses Research and development expenses are charged to expense as incurred. Research and development expenses include those for certain payroll and personnel; laboratory supplies; consulting; manufacturing; external clinical; and allocated overhead, including rent, equipment depreciation, and utilities. We record accrued liabilities for estimated costs of our research and development activities conducted by third-party service providers. We record the estimated costs of research and development activities based upon the estimated amount of services provided but not yet invoiced and include these costs in accrued liabilities in the consolidated balance sheets and within research and development expenses in the consolidated statements of operations and comprehensive loss. We accrue for these costs based on factors such as estimates of the work completed and in accordance with the third-party service agreements. If we do not identify costs that have begun to be incurred or if we underestimate or overestimate the level of services performed or the costs of these services, actual expenses could differ from our estimates. To date, we have not experienced any material differences between accrued costs and actual costs incurred. We make payments in connection with clinical trials to contract manufacturing organizations (“CMOs”) that manufacture the material for our product candidates and to clinical research organizations (“CROs”) and clinical trial sites that conduct and manage our clinical trials. The financial terms of these contracts are subject to negotiation, which vary by contract and may result in payments that do not match the periods over which materials or services are provided. Generally, these agreements set forth the scope of work to be performed at a fixed fee, unit price or on a time and materials basis. In the event we make advance payments for goods or services that will be used or rendered for future research and development activities, the payments are deferred and capitalized as a prepaid expense and recognized as expense as the goods are received or the related services are rendered. These payments are evaluated for current or long-term classification based on when they are expected to be realized. Acquisition of In-Process Research and Development Assets We measure and recognize acquired in-process research and development assets, which include licenses, know-how, patents, and transaction fees, based on the cost to acquire the assets and the consideration is allocated to the items based on a relative fair value methodology. Goodwill is not recognized in asset acquisitions. If acquired in-process technology is determined to not have an alternative future use, the cost is charged to research and development expenses at the acquisition date. Patent Costs We expense patent costs as incurred for filing, prosecuting, and maintaining patents and patent applications, including certain of the patents and patent applications that we license from third parties. We classify these costs as general and administrative expenses in our consolidated statements of operations and comprehensive loss. In addition, we are entitled to receive reimbursement from third parties for a portion of the filing, prosecution, and maintenance costs for certain patents and patent applications. We accrue for these reimbursements as the respective expenses are incurred, and we classify such reimbursements as a reduction of general and administrative expenses. During the years ended December 31, 2023 and 2022, we incurred gross patent costs of $ 4.3 million and $ 7.3 million, respectively. During the years ended December 31, 2023 and 2022, we recorded $ 1.5 million and $ 3.5 million, respectively, of patent cost reimbursements as a credit to general and administrative expenses. Stock-Based Compensation Expense Stock-based compensation expense related to awards to employees is measured at the grant date based on the fair value of the award. We determine the grant-date fair value of the options using the Black-Scholes option-pricing model. The fair value of restricted stock units (“RSUs”) and performance-based RSUs (“PSUs”) awards is determined based on the number of units granted and the closing price of our common stock as of the grant-date. The fair value of the award that is ultimately expected to vest is recognized as expense on a straight-line basis over the requisite service period of the awards, which is generally the vesting period, and is adjusted for pre-vesting forfeitures in the period in which the forfeitures occur. F-12 Table of Contents We use the Black-Scholes valuation model as the method for determining the estimated fair value of stock options and stock purchases under our 2021 Employee Stock Purchase Plan (“ESPP”) with the following assumptions: Fair Market Value of Common Stock — Prior to our Initial Public Offering (“IPO”), the fair market value of our common stock was determined by our board of directors with assistance from management and external valuation experts. Our approach to estimating the fair market value of our common stock was consistent with the methods outlined in the American Institute of Certified Public Accountants’ Practice Aid, Valuation of Privately-Held-Company Equity Securities Issued as Compensation. Following our IPO, the fair market value of our common stock is based on its closing price on Nasdaq as reported on the date of the stock option grant. Expected Term — Expected term represents the period that our stock-based awards are expected to be outstanding and is determined using the simplified method. The expected term for our stock purchases under our ESPP is the offering period. Expected Volatility — Expected volatility is estimated based on the average historical volatilities of common stock of comparable publicly traded entities over a period equal to the expected term of the stock option grants , as we do not have sufficient trading history for our common stock. Comparable companies are chosen based on their size, stage in the life cycle, or area of specialty. We will continue to apply this process for stock options and ESPP stock purchases until enough historical information regarding the volatility of our stock price becomes available. Expected Dividends — Expected dividends is zero as we have never paid dividends on our common stock and have no plans to do so for the foreseeable future. Risk-Free Interest Rate — Risk-free interest rate is based on the U.S. Treasury zero-coupon issued in effect at the time of grant for periods corresponding with the expected term of the award. Income Taxes We account for income taxes using the asset and liability method. We recognize deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the consolidated financial statements or tax returns. Deferred tax assets and liabilities are determined based on the difference between the consolidated financial statements and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Valuation allowances are provided if, based upon the weight of available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. Tax benefits related to uncertain tax positions are recognized when it is more likely than not that a tax position will be sustained during an audit. Interest and penalties related to unrecognized tax benefits are included within the provision for income tax. Other Income, net We recognize fees earned from sources not considered to be within the normal course of business in other income within the statements of operations and comprehensive loss. During the years ended December 31, 2023 and 2022, we recognized $ 15.3 million and $ 4.6 million of interest income from our short-term and long-term marketable securities, respectively . Comprehensive Loss Comprehensive loss is composed of net loss and other comprehensive income (loss). Other comprehensive income (loss) consists of unrealized gains and losses on available-for-sale marketable securities. Net Loss Per Share Basic net loss per share is computed by dividing the net loss by the weighted-average number of common shares outstanding during the period, without consideration of potential dilutive securities. Diluted net loss per share is computed by dividing the net loss by the sum of the weighted-average number of common shares outstanding during the period plus the dilutive effects of potentially dilutive securities outstanding during the period. Potentially dilutive securities include common stock options, RSUs issued and outstanding. For all periods presented, diluted net loss per share is the same as basic net loss per share since the effect of including potential common shares is anti-dilutive. F-13 Table of Contents Recent Accounting Pronouncements From time to time, new accounting pronouncements are issued by FASB or other standard-setting bodies and adopted are by us as of the specified effective date. In June 2016, the FASB issued ASU 2016-13, Financial Instruments—Credit Losses: Measurement of Credit Losses on Financial Instruments (Topic 326). This ASU provides guidance on the measurement of credit losses for most financial assets and certain other instruments that are not measured at fair value through net income. ASU 2016-13 replaces the current incurred loss impairment approach with a methodology to reflect expected credit losses and requires consideration of a broader range of reasonable and supportable information to explain credit loss estimates. This ASU is to be applied on a modified retrospective approach and is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2022. Early adoption is permitted for all entities for fiscal years beginning after December 15, 2018, and interim periods therein. We adopted ASU 2016-13 on January 1, 2023. The impact of ASU 2016-13 on our financial statements and related disclosures was not material. New Accounting Pronouncements Not Yet Adopted In October 2023, the FASB issued ASU 2023-06, Disclosure Improvements: Codification Amendments in Response to the SEC’s Disclosure Update and Simplification Initiative. This ASU aligns the requirements in the ASC to the removal of certain disclosure requirements set out in Regulation S-X and Regulation S-K, announced by the U.S. Securities and Exchange Commission (“SEC”). The effective date for each amended topic in the ASC is either the date on which the SEC’s removal of the related disclosure requirement from Regulation S-X or Regulation S-K becomes effective, or on June 30, 2027, if the SEC has not removed the requirements by that date. Early adoption is prohibited. We are currently evaluating the impact of the adoption of this standard. In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. This ASU requires public entities to disclose information about their reportable segments’ significant expenses and other segment items on an interim and annual basis. Public entities with a single reportable segment are required to apply the disclosure requirements in ASU 2023-07, as well as all existing segment disclosures and reconciliation requirements in ASC 280 on an interim and annual basis. ASU 2023-07 is effective for fiscal years beginning after December 15, 2023, and for interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted. We are currently evaluating the impact of the adoption of this standard. In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. This ASU requires public entities, on an annual basis, to provide disclosure of specific categories in the rate reconciliation, as well as disclosure of income taxes paid disaggregated by jurisdiction. ASU 2023-09 is effective for fiscal years beginning after December 15, 2024, with early adoption permitted. We are currently evaluating the impact the adoption of this standard. Emerging Growth Company and Smaller Reporting Company Status We are an emerging growth company, as defined in the Jumpstart Our Business Startups Act of 2012 Act (“JOBS” Act”). Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act until such time as those standards apply to private companies. We have elected to use this extended transition period for complying with new or revised accounting standards that have different effective dates for public and private companies until the earlier of the date that we (a) are no longer an emerging growth company or (b) affirmatively and irrevocably opt out of the extended transition period provided in the JOBS Act. As a result, our consolidated financial statements may not be comparable to those of companies that comply with the new or revised accounting pronouncements as of public company effective dates. We expect to use the extended transition period for any other new or revised accounting standards during the period in which we remain an emerging growth company. We have early adopted certain accounting standards because the JOBS Act does not preclude an emerging growth company from adopting a new or revised accounting standard earlier than the time that such standard applies to private companies to the extent early adoption is allowed by the accounting standard. We are also a “smaller reporting company.” If we are a smaller reporting company at the time we cease to be an emerging growth company, we may continue to rely on exemptions from certain disclosure requirements that are available to smaller reporting companies. Specifically, as a smaller reporting company, we may choose to present only the two most F-14 Table of Contents recent fiscal years of audited consolidated financial statements in our Annual Report on Form 10-K and, similar to emerging growth companies, smaller reporting companies have reduced disclosure obligations regarding executive compensation. 3. Fair Value Measurements and Fair Value of Financial Instruments The authoritative guidance on fair value measurements establishes a three-tier fair value hierarchy for disclosure of fair value measurements as follows: Level 1—Quoted prices in active markets for identical assets or liabilities. Level 2—Observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. Assets and liabilities measured at fair value are classified in their entireties based on the lowest level of input that is significant to the fair value measurement. Our assessment of the significance of a particular input to the fair value measurement in its entirety requires our management to make judgments and consider factors specific to the asset or liability. Our financial instruments consist of Level 1, Level 2, and Level 3 financial instruments. We generally classify our marketable securities as Level 1 or Level 2. Instruments are classified as Level 2 when observable market prices for identical securities that are traded in less active markets are used. When observable market prices for identical securities are not available, such instruments are priced using benchmark curves, benchmarking of like securities, sector groupings, matrix pricing, and valuation models. These valuation models are proprietary to the pricing providers or brokers and incorporate a number of inputs, including in approximate order of priority: benchmark yields, reported trades, broker/dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids, offers, and reference data including market research publications. For certain security types, additional inputs may be used, or some of the standard inputs may not be applicable. Evaluators may prioritize inputs differently on any given day for any security based on market conditions, and not all inputs listed are available for use in the evaluation process for each security valuation on any given day. Changes in the ability to observe valuation inputs may result in a reclassification of levels of certain securities within the fair value hierarchy. We recognize transfers into and out of levels within the fair value hierarchy in the period in which the actual event or change in circumstances that caused the transfer occurs. No such transfers occurred during the years ended December 31, 2023 and 2022. Level 1 financial instruments are comprised of money market fund investments and U.S. Treasury bills. Level 2 financial instruments are comprised of commercial paper, corporate debt securities, and U.S. government agency bonds. Financial assets and liabilities are considered Level 3 when their fair values are determined using pricing models, discounted cash flow methodologies, or similar techniques, and at least one significant model assumption or input is unobservable. Level 3 financial instruments consist of the MSKCC success payments liability. F-15 Table of Contents The following table sets forth our financial instruments that were measured at fair value on a recurring basis by level within the fair value hierarchy (in thousands): Fair Value Measurements as of December 31, 2023 Total Level 1 Level 2 Level 3 Assets: U.S. Treasury bills ($ 23,527 included in cash and cash equivalents) $ 262,439 $ 262,439 $ — $ — Commercial paper ($ 9,759 included in cash and cash equivalents) 40,373 — 40,373 — U.S. government agency bonds 40,185 — 40,185 — Money market fund investments (included in cash and cash equivalents) 17,876 17,876 — — Corporate debt securities 11,531 — 11,531 — Total fair value of assets $ 372,404 $ 280,315 $ 92,089 $ — Liabilities: MSKCC success payments liability $ 2,939 $ — $ — $ 2,939 Total fair value of liabilities $ 2,939 $ — $ — $ 2,939 Fair Value Measurements as of December 31, 2022 Total Level 1 Level 2 Level 3 Assets: Commercial paper ($ 26,669 included in cash and cash equivalents) $ 96,899 $ — $ 96,899 $ — U.S. Treasury bills 91,966 91,966 — — U.S. government agency bonds ($ 3,976 included in cash and cash equivalents) 63,659 — 63,659 — Corporate debt securities 36,819 — 36,819 — Money market fund investments (included in cash and cash equivalents) 27,693 27,693 — — Total fair value of assets $ 317,036 $ 119,659 $ 197,377 $ — Liabilities: MSKCC success payments liability $ 1,651 $ — $ — $ 1,651 Total fair value of liabilities $ 1,651 $ — $ — $ 1,651 F-16 Table of Contents The fair value and amortized cost of cash equivalents and available-for-sale marketable securities by major security type as of December 31, 2023 and 2022 are presented in the following tables (in thousands): As of December 31, 2023 Amortized Cost Basis Unrealized Gains Unrealized Losses Estimated Fair Value U.S. Treasury bills ($ 23,527 included in cash and cash equivalents) $ 262,328 $ 331 $ ( 220 ) $ 262,439 Commercial paper ($ 9,759 included in cash equivalents) 40,386 — ( 13 ) 40,373 U.S. government agency bonds 40,295 1 ( 111 ) 40,185 Money market fund investments (included in cash equivalents) 17,876 — — 17,876 Corporate debt securities 11,489 50 ( 8 ) 11,531 Total cash equivalents and marketable securities $ 372,374 $ 382 $ ( 352 ) $ 372,404 Classified as: Cash and cash equivalents $ 51,162 Marketable securities, short-term 277,665 Marketable securities, long-term 43,577 Total cash equivalents and marketable securities $ 372,404 As of December 31, 2022 Amortized Cost Basis Unrealized Gains Unrealized Losses Estimated Fair Value Commercial paper ($ 26,669 included in cash equivalents) 97,024 6 ( 131 ) 96,899 U.S. Treasury bills 92,910 1 ( 945 ) 91,966 U.S. government agency bonds ( 3,976 included in cash and cash equivalents) 63,926 25 ( 292 ) 63,659 Corporate debt securities 37,002 — ( 183 ) 36,819 Money market fund investments (included in cash equivalents) $ 27,693 $ — $ — $ 27,693 Total cash equivalents and marketable securities $ 318,555 $ 32 $ ( 1,551 ) $ 317,036 Classified as: Cash equivalents $ 58,338 Marketable securities, short-term 189,325 Marketable securities, long-term 69,373 Total cash equivalents and marketable securities $ 317,036 During the years ended December 31, 2023 and 2022, we reviewed our impaired marketable securities and concluded that the decline in fair value was not related to credit losses and is recoverable. Accordingly, no allowance for credit losses was recorded and instead the unrealized losses are reported as a component of accumulated other comprehensive loss. F-17 Table of Contents The following table presents the fair value of available-for-sale marketable securities by contractual maturities (in thousands): December 31, 2023 Due in less than one year $ 277,665 Due in one to five years 43,577 Total $ 321,242 The following table sets forth a summary of the changes in the fair value of our Level 3 financial liability (in thousands): MSKCC Success Payments Liability Balance at December 31, 2021 $ 4,080 Change in fair value ( 2,429 ) Balance at December 31, 2022 $ 1,651 Change in fair value 1,288 Balance at December 31, 2023 $ 2,939 Our liability for the MSKCC success payments is carried at fair value and changes are recognized as expense or income as part of other income (expense) until the success payments liability is paid or expires (Note 4). The table below summarizes key assumptions used in the valuation of MSKCC success payments liability: As of December 31, 2023 As of December 31, 2022 Fair value of common stock $ 5.73 $ 6.28 Risk-free interest rate 3.88 % 3.88 % Expected volatility 79 % 79 % Probability of achieving multiple of Initial Share Price (1) 5.2 % to 18.1 % 3.0 % to 10.6 % Expected term (years) 3.7 to 5.2 4.6 to 6.0 (1) MSKCC is entitled to certain success payments if our common stock fair value increases by certain multiples of value based on a comparison of the fair market value of our common stock to $ 5.1914 per share, adjusted for any future stock splits (“Initial Share Price”), during a specified time period (Note 4). The computation of expected volatility was estimated using a combination of available information about the historical volatility of stocks of similar publicly traded companies for a period matching the expected term assumption and the historical and implied volatility of our stock. The risk-free interest rate, expected volatility, and expected term assumptions depend on the initiation of our AMpLify phase 1 clinical trial for our CB-012 product candidate utilizing the know-how, biological materials, and intellectual property licensed under the Exclusive License Agreement, dated November 13, 2020, with MSKCC (“MSKCC Agreement”) and the estimated timing of marketing approval for this product candidate from the U.S. Food and Drug Administration (“FDA”). In addition, we incorporated the estimated number and timing of valuation measurement dates in the calculation of the MSKCC success payments liability. 4. Significant Agreements The Regents of the University of California and the University of Vienna We entered into an Exclusive License Agreement, dated April 16, 2013 (as amended, “UC/Vienna Agreement”) with The Regents of the University of California (“UC”) and the University of Vienna (“Vienna”) (together, “UC/Vienna”) wherein UC/Vienna granted us an exclusive worldwide license, with the right to sublicense, in all fields to the foundational F-18 Table of Contents CRISPR-Cas9 patent family co-owned by UC, Vienna, and Dr. Emmanuelle Charpentier (“CVC IP”). Dr. Charpentier has not granted us any rights, either directly or indirectly. The UC/Vienna Agreement continues until the last-to-expire patent or last-to-be-abandoned patent application within the CVC IP; provided, however, that UC/Vienna may terminate the UC/Vienna Agreement upon the occurrence of certain events and we may terminate the UC/Vienna Agreement at our sole discretion upon written notice. Without patent term adjustment (“PTA”) or patent term extension (“PTE”), the CVC IP will expire in 2033. The UC/Vienna Agreement includes certain diligence milestones that we must meet. For products and services sold by us that are covered by the CVC IP, we will owe low- to mid-single-digit percent royalties on net sales, subject to a minimum annual royalty. Prior to the time that we are selling products, we owe UC/Vienna an annual license maintenance fee. We may owe UC/Vienna up to $ 3.4 million in certain regulatory and clinical milestone payments in the field of human therapeutics and diagnostics for products that are covered by the CVC IP and developed by us, an affiliate, or a sublicensee. Additionally, we pay UC/Vienna a specified percentage of sublicensing revenue, including cash and equity, we receive from sublicensing the CVC IP, subject to certain exceptions. If we include intellectual property owned or controlled by us in a sublicense to the CVC IP, we pay UC/Vienna a low double-digit percentage of sublicensing revenues received under the sublicense. If we do not include intellectual property owned or controlled by us in a sublicense to the CVC IP, we pay UC/Vienna 50 % of sublicensing revenues received under the sublicense. To date, we have entered into over 25 sublicensing agreements in a variety of fields such as human therapeutics, forestry, agriculture, research reagents, transgenic animals, certain livestock targets, internal research, bioproduction, cell lines, and microbial applications that include the CVC IP as well as other Cas9 intellectual property owned or controlled by us. We are obligated to reimburse UC for its prosecution and maintenance costs of the CVC IP. For the years ended December 31, 2023 and 2022, we incurred $ 1.6 million and $ 1.1 million, respectively, for payments we owe to UC related to sublicensing revenues, which we recorded in research and development expenses in our consolidated statements of operations and comprehensive loss. For the years ended December 31, 2023 and 2022, we reimbursed UC $ 2.3 million and $ 5.4 million, respectively, for prosecution and maintenance costs of the CVC IP, which were recorded in general and administrative expenses in our consolidated statements of operations and comprehensive loss. On December 15, 2016, we entered into a Consent to Assignments, Licensing and Common Ownership and Invention Management Agreement (“IMA”) relating to the CVC IP. Under the IMA, CRISPR Therapeutics AG (“CRISPR”) reimburses us 50 % of the amounts we reimburse UC for patent prosecution and maintenance costs of the CVC IP. For the years ended December 31, 2023 and 2022, CRISPR reimbursed us $ 1.1 million and $ 2.7 million, respectively, which we recorded as reductions of general and administrative expenses in our consolidated statements of operations and comprehensive loss. Memorial Sloan Kettering Cancer Center On November 13, 2020, we entered into the MSKCC Agreement, under which we exclusively licensed know-how, biological materials, and patent families relating to fully-human single-chain variable fragments targeting C-type lectin-like molecule-1 (“CLL-1”; also known as CD371) for use in T cells, NK cells, and genome-edited induced pluripotent stem cells (“iPSCs”) for allogeneic CLL-1-targeted cell therapies (currently used in our CB-012 product candidate). We paid MSKCC an upfront payment of $ 0.5 million in cash and $ 2.1 million in stock. For each licensed CLL-1 product, we may owe potential clinical, regulatory, and commercial milestone payments totaling $ 112.0 million. In addition, in the event we, our affiliates, or sublicensees, receive regulatory approval for a licensed CLL-1 product, we will owe low- to mid-single-digit percent royalties on net sales by us, our affiliates, and our sublicensees. Our license from MSKCC includes the right to sublicense through multiple tiers and we will owe MSKCC a percentage of upfront cash or equity received from our sublicensees. The percentage owed decreases as our licensed CLL-1 product candidate moves through development, starting at a low-double-digit percentage if clinical trials have not yet begun and decreasing to a mid-single-digit percentage if our licensed CLL-1 product candidate is in later clinical trial stages. We are also responsible for paying a percentage of licensed patent costs. The MSKCC Agreement includes certain diligence milestones that we must meet by specified dates, which may be extended upon payment of additional fees. MSKCC is entitled to certain success payments if our common stock fair value increases by certain multiples of increasing value based on a comparison of the fair market value of our common stock to $ 5.1914 per share, adjusted for any future stock splits (the “Initial Share Price”), during a specified time period. Under the MSKCC Agreement, as a publicly traded company, our common stock fair value is determined by any given 45-day volume weighted-average trading price. At our option, success payments to MSKCC may be made in cash or common stock. The relevant time period commences when the first patient is dosed with the first licensed CLL-1 product candidate (CB-012) in the first phase 1 clinical trial and ends upon the earlier of the third anniversary from the approval of our, or our affiliate’s, or sublicensee’s F-19 Table of Contents biologics license application (“BLA”) by the FDA or 10 years from the date the first patient was dosed with a licensed CLL-1 product candidate in the first phase 1 clinical trial. The aggregate success payments will not exceed $ 35.0 million. Additionally, if we undergo a change of control during the specified time period, we may owe a change of control payment, depending upon the increase in our stock price due to the change of control and also to what extent success payments have already been paid by us to MSKCC. In no event will the combination of success payments and the change of control payment owed to MSKCC exceed $ 35.0 million. The following table summarizes the amounts of the MSKCC success payments: Multiple of Initial Share Price giving rise to a success payment 5 x 10 x 15 x MSKCC success payments (in millions) $ 10.0 $ 10.0 $ 15.0 We may terminate the MSKCC Agreement upon 90 calendar days’ prior written notice to MSKCC. MSKCC may terminate the MSKCC Agreement in the event of our uncured material breach, bankruptcy, or criminal activity. If MSKCC materially breaches the MSKCC Agreement in certain circumstances (e.g., granting a third party a license in our field) then, during the time of such uncured breach, MSKCC will not be entitled to receive any success payments or any change of control payment. As of December 31, 2023 and 2022, the estimated fair value of the total success payments obligation to MSKCC was $ 2.9 million and $ 1.7 million, respectively, which was included in long-term liabilities in our consolidated balance sheets. Intellia Therapeutics, Inc. On July 16, 2014, we entered into a License Agreement (as amended, “Intellia License Agreement”) with Intellia, LLC, to which Intellia Therapeutics, Inc. (“Intellia”) is a successor in interest. Under the Intellia License Agreement, we granted Intellia an exclusive worldwide license, with the right to sublicense, to certain CRISPR-Cas9 technology for a defined field of human therapeutics. Intellia granted us an exclusive worldwide license, with the right to sublicense, to certain of its CRISPR-Cas9 technology for all fields outside of the defined field of human therapeutics. Under the Intellia License Agreement, each party is responsible for 30 % of the other party’s expenses for prosecution and maintenance of the licensed intellectual property. During each of the years ended December 31, 2023 and 2022, we recognized less than $ 0.1 million of expenses in reimbursable patent prosecution and maintenance costs, which were recorded as general and administrative expenses in our consolidated statements of operations and comprehensive loss. During each of the years ended December 31, 2023 and 2022, Intellia reimbursed us $ 0.4 million and $ 0.8 million, respectively (including reimbursement for a portion of the patent prosecution and maintenance costs of the CVC IP paid to UC), which were recorded as reductions of general and administrative expenses in our consolidated statements of operations and comprehensive loss. The term of the Intellia License Agreement continues for the life of the licensed patents and patent applications; provided, however, either party may terminate the agreement upon the occurrence of certain events. On June 16, 2021, we entered into a leaseback agreement with Intellia (“Leaseback Agreement”). Pursuant to the Leaseback Agreement, in exchange for Intellia’s grant to us of an exclusive license to certain intellectual property relating to CRISPR-Cas9, including Cas9 chRDNAs, for use solely in the manufacture of our CB-010 product candidate, we paid Intellia an upfront cash payment of $ 1.0 million and will pay up to $ 23.0 million in potential future regulatory and sales milestones. Additionally, we will owe Intellia low- to mid- single-digit percent royalties on net sales of our CB-010 product candidate by us, our affiliates, and sublicensees until the expiration, abandonment, or invalidation of the last patent within the intellectual property relating to CRISPR-Cas9, including that relating to Cas9 chRDNAs (i.e., 2036, without PTA or PTE). Pioneer Hi-Bred International, Inc. (now Corteva Agriscience) On July 13, 2015, we and Pioneer Hi-Bred International, Inc. (“Pioneer”) (now Corteva Agriscience), then a DuPont company (“DuPont”), entered into an Amended and Restated Collaboration and License Agreement (as amended, “Pioneer Agreement”). Under the terms of the Pioneer Agreement, we and Pioneer cross licensed CRISPR intellectual property portfolios. Pioneer granted us an exclusive worldwide license, with the right to sublicense, to its CRISPR intellectual property in the field of research tools, as well as a non-exclusive worldwide license to such intellectual property in human and animal therapeutics, industrial biotechnology, certain agriculture segments, and other fields; and we granted F-20 Table of Contents Pioneer an exclusive worldwide license, with the right to sublicense, to our CRISPR intellectual property, including the CVC IP, in a defined field of agriculture relating to specified row crops, as well as a non-exclusive worldwide license to the intellectual property in other agricultural applications, industrial biotechnology, nutrition and health, and other fields. The Pioneer Agreement continues until the expiration, abandonment, or invalidation of the last patent or patent application within the licensed intellectual property; provided, however, that the parties may terminate the Pioneer Agreement by mutual consent or either party may unilaterally terminate the Pioneer Agreement in the event of an uncured breach of a payment obligation, bankruptcy, or failure to maintain or own licensed intellectual property by the other party if the non-breaching party is materially adversely affected by the failure. We are obligated to pay low-single-digit percent royalties to Pioneer for the sales of our products in the research tools field as well as certain sublicensing revenues in that field. We are eligible to receive milestone payments from Pioneer if certain regulatory and commercial milestones are met related to specified row crops, for a total of up to $ 22.4 million, as well as to receive low-single-digit percent royalties for sales of defined agricultural products and certain sublicensing revenues in that field. Initially, Pioneer owned the patents and patent applications developed under the collaboration, including the chRDNA patent family, and granted us an exclusive license to these patents and patent applications in the fields of research tools and therapeutics. In December 2020, we and Pioneer entered into an amendment to the Pioneer Agreement under which Pioneer assigned to us the chRDNA patent family developed under the research collaboration, and we paid Pioneer an upfront payment of $ 0.5 million. We considered the payment to Pioneer in accordance with revenue recognition guidance and accounted for it as a reduction of the licensing and collaboration revenue in our consolidated statements of operations and comprehensive loss. In addition to the upfront payment, we are now obligated to pay all patent prosecution and maintenance costs for the chRDNA patent family; up to $ 2.8 million in regulatory milestone payments for therapeutic products developed by us, our affiliates, or licensees that are covered by the chRDNA patent family; up to $ 20.0 million in sales milestones over a total of four therapeutics products sold by us, our affiliates, or licensees that are covered by the chRDNA patent family; and a low-single-digit percentage of licensing revenue we receive for licensing the chRDNA patent family after December 2020. During the year ended December 31, 2023 we incurred no liability for payments owed to Pioneer for licensing revenues. During the year ended December 31, 2022, we incurred $ 0.1 million, for payments we owe to Pioneer related to licensing revenues, which we recorded as a research and development expense in our consolidated statements of operations and comprehensive loss. AbbVie Manufacturing Management Unlimited Company On February 9, 2021, we entered into a Collaboration and License Agreement (as amended, “AbbVie Agreement”) with AbbVie Manufacturing Management Unlimited Company (“AbbVie”). Pursuant to the AbbVie Agreement, AbbVie selected one target or, for a dual CAR-T cell product, two targets (each selection, a “Program Slot”) to develop collaboration CAR-T cell products (and corresponding licensed products). Under the terms of the AbbVie Agreement, we conducted certain preclinical research and development activities under the collaboration. AbbVie reimbursed us for all such activities, including reimbursement for time spent by employees at a designated rate. On September 26, 2023, we received notice from AbbVie that AbbVie elected to terminate the AbbVie Agreement. By mutual agreement with AbbVie, termination of the AbbVie Agreement became effective on October 25, 2023. The transaction price we received under the AbbVie Agreement associated with the first two Program Slots consisted of a $ 30.0 million upfront, non-refundable and non-creditable, cash payment and the estimated variable consideration related to our performance of preclinical research, development, and manufacturing activities under the collaboration and the developmental and regulatory milestone payments. We constrain the estimated variable consideration if we assess that it is probable that a significant reversal in the amount of cumulative revenue recognized may occur in future periods. The transaction price was reevaluated at the end of each reporting period and as changes in circumstances occurred. We determined that the licenses we granted to AbbVie and our participation in the joint governance committee were not capable of being distinct from the preclinical research, development, and manufacturing activities and therefore were combined into one performance obligation. We recognized revenue based on the measure of progress using an estimated cost-based input method each reporting period. Upon to receipt of the termination notice, we stopped performing preclinical research and development services under the AbbVie Agreement and determined that our performance obligation to AbbVie was substantially completed as of September 30, 2023. Consequently, the remaining $ 20.8 million of deferred revenue from the $ 30.0 million upfront cash payment was recognized upon satisfaction of the performance obligation during the year ended December 31 2023. F-21 Table of Contents We had no long-term or short-term deferred revenue related to the upfront cash payment in our consolidated balance sheets as of December 31, 2023. We had short-term deferred revenue of $ 9.4 million and long-term deferred revenue of $ 13.3 million related to the upfront cash payment in our consolidated balance sheets as of December 31, 2022. During the year ended December 31, 2023, we recognized $ 24.8 million in licensing and collaboration revenue associated with the AbbVie Agreement, of which $ 22.7 million had been included in deferred revenue as of the beginning of the period. During the year ended December 31, 2022, we recognized $ 8.0 million in licensing and collaboration revenue associated with the AbbVie Agreement. As of December 31, 2023 and 2022, we had no amounts recorded in accounts receivable in our consolidated balance sheets. As of December 31, 2023, we had no contract assets in our consolidated balance sheets. As of December 31, 2022, we had $ 0.9 million in contract assets in our consolidated balance sheets. 5. Revenue Disaggregation of Revenue We disaggregate revenue by geographical market based on the location of research and development activities of our licensees and collaborators. The following table is a summary of revenue by geographic location for the years ended December 31, 2023 and 2022, (in thousands): Years Ended December 31, 2023 2022 United States $ 32,770 $ 13,303 Rest of world 1,707 548 Total $ 34,477 $ 13,851 During the year ended December 31, 2023, we recognized $ 8.4 million of revenue related to performance obligations satisfied at a point in time, and we recognized $ 26.1 million of revenue related to performance obligations satisfied over time that included $ 24.8 million in licensing and collaboration revenue associated with the AbbVie Agreement, of which $ 22.7 million had been included in deferred revenue as of the beginning of the period. During the year ended December 31, 2022, we recognized $ 5.9 million of revenue related to performance obligations satisfied at a point in time, and we recognized $ 8.0 million of revenue related to performance obligations satisfied over time. Contract Balances Accounts receivable relate to our right to consideration for performance obligations completed (or partially completed) for which we have an unconditional right to consideration. Our accounts receivable balances represent amounts that we billed to our licensees with invoices outstanding as of the end of a reporting period. Contract assets are rights to consideration in exchange for a license that we have granted to a licensee when the right is conditional on something other than the passage of time. Our contract asset balances represent reimbursable research costs related to the AbbVie Agreement, as well as royalties and milestone payments from our other license agreements that are unbilled as of the end of a reporting period. Contract liabilities consist of deferred revenue and relate to amounts invoiced to, or advance consideration received from, licensees that precede our satisfaction of the associated performance obligations. As of December 31, 2023, our deferred revenue balance primarily resulted from the upfront payment received relating to our performance obligation to Pfizer, Inc. (“Pfizer”). As of December 31, 2022 our deferred revenue balance primarily result from the upfront payment received relating to our performance obligations under the now-terminated AbbVie Agreement. The remaining deferred revenue relates to upfront payments received under license agreements that also include nonrefundable annual license fees, which are accounted for as material rights for license renewals and are recognized at the point in time annual license fees are paid by the licensees and the renewal periods begin. F-22 Table of Contents The following table presents changes in our contract assets and liabilities during the year ended December 31, 2023 (in thousands): Balance as of December 31, 2022 Additions Deductions Balance as of December 31, 2023 Accounts receivable $ 202 $ 10,819 $ ( 10,873 ) $ 148 Contract assets: Unbilled accounts receivable $ 2,247 $ 6,006 $ ( 6,828 ) $ 1,425 Contract liabilities: Deferred revenue, current and long-term $ 25,891 $ 12,981 $ ( 29,923 ) $ 8,949 Unbilled accounts receivable decreased during the year ended December 31, 2023, primarily due to the decrease in unbilled research costs under the AbbVie Agreement. Deferred revenue decreased during the year ended December 31, 2023, primarily due to the recognition of deferred revenues related to the satisfaction of our performance obligation to AbbVie as a result of AbbVie’s termination of the AbbVie Agreement, offset by the $ 7.5 million allocated to the Pfizer information sharing committee (Notes 4 and 7). During the years ended December 31, 2023 and 2022, we recognized $ 23.2 million and $ 5.0 million of revenue, respectively, which was included in the opening contract liabilities balances at the beginning of the respective periods. Transaction Prices Allocated to Remaining Performance Obligations Remaining performance obligations represent in aggregate the amount of a transaction price that has been allocated to performance obligations not delivered as of the end of a reporting period. The value of transaction prices allocated to remaining unsatisfied performance obligations as of December 31, 2023 and 2022 were approximately $ 8.9 million and $ 40.4 million, respectively. We expect to recognize approximately $ 2.8 million of remaining performance obligations as revenue in the next 12 months and to recognize the remainder thereafter. Capitalized Contract Acquisition Costs and Fulfillment Costs We did not incur any expenses to obtain license and collaboration agreements, and costs to fulfill those contracts do not generate or enhance our resources. As such, no costs to obtain or fulfill a contract have been capitalized in any period. 6. Balance Sheet Items Other receivables consisted of the following (in thousands): December 31, 2023 December 31, 2022 Patent cost reimbursements $ 1,403 $ 1,638 Accrued interest on marketable securities 702 570 Other 181 7 Total $ 2,286 $ 2,215 F-23 Table of Contents Prepaid expenses and other current assets consisted of the following (in thousands): December 31, 2023 December 31, 2022 Prepaid contract manufacturing and clinical costs $ 3,942 $ 4,803 Prepaid income taxes — 431 Prepaid insurance 993 1,568 Other 1,220 1,119 Total $ 6,155 $ 7,921 Property and equipment, net, consisted of the following (in thousands): December 31, 2023 December 31, 2022 Lab equipment $ 15,581 $ 12,588 Leasehold improvements 2,235 1,876 Computer equipment 895 709 Furniture and office equipment 499 161 Construction in progress 8,204 993 Total property and equipment 27,414 16,327 Less accumulated depreciation and amortization ( 9,144 ) ( 5,649 ) Property and equipment, net $ 18,270 $ 10,678 Depreciation and amortization expenses related to property and equipment were $ 3.5 million and $ 1.6 million, for the years ended December 31, 2023, and 2022, respectively. Accrued expenses and other current liabilities consisted of the following (in thousands): December 31, 2023 December 31, 2022 Accrued employee compensation and related expenses 9,517 5,752 Accrued research and development expenses 8,720 6,731 Accrued patent expenses 613 1,331 Accrued expenses related to sublicensing revenues 802 596 Credit card liability 377 299 Other 1,106 1,370 Total $ 21,135 $ 16,079 7. Related Party Transactions Edge Animal Health On May 15, 2020, we entered into an Exclusive License Agreement for Veterinary Therapeutics (as amended, “Edge chRDNA License Agreement”) with Edge Animal Health (“Edge”), a private company, related party, under which we granted Edge an exclusive worldwide license to Cas9 and Cas12a chRDNA intellectual property rights and know-how in the defined field of veterinary therapeutics. As consideration for this exclusive license, Edge issued to us 7,500,000 shares of convertible preferred stock with an estimated fair value of $ 7.5 million, which was the price paid for similar shares by another investor, and which was an arm’s length transaction. This represents a material voting interest in Edge and entitles us to hold one of the four board of director seats. As of December 31, 2023, we had appointed one of the four Edge directors. We concluded that Edge is a variable interest entity and that we are not its primary beneficiary based on our representation on its board of directors. As Edge’s convertible preferred stock is not in substance common stock, we recorded this investment using the measurement alternative. As of each of December 31, 2023 and 2022, the carrying value F-24 Table of Contents of the Edge investment was $ 7.5 million. There have been no changes to the carrying value of the investment during the years ended December 31, 2023 and 2022. On May 16, 2023, we entered into an Exclusive License Agreement for Veterinary Therapeutics (CRISPR-Cas9) (“Edge Cas9 License Agreement”), under which we granted Edge an exclusive worldwide license to certain CRISPR-Cas9 intellectual property rights in the field of veterinary therapeutics. Previously, on May 15, 2020, we had entered into an Option for an Exclusive License under which Edge could exercise its option within three years upon payment of a total of $ 1.2 million, which Edge paid, and we entered into the Edge Cas9 License Agreement. We recognized $ 1.2 million of revenue in connection with the Edge Cas9 License Agreement during the twelve months ended December 31, 2023. We did no t recognize any revenue in connection with the Edge Cas9 License Agreement in 2022. Pfizer Investment On June 29, 2023, we entered into a Securities Purchase Agreement (“Securities Purchase Agreement”) with Pfizer, pursuant to which we, in a private placement transaction, issued and sold to Pfizer 4,690,431 shares of our common stock, par value $ 0.0001 per share, at a purchase price of $ 5.33 per share, for aggregate gross proceeds of approximately $ 25.0 million (“Pfizer Investment”). The issuance and sale of the shares to Pfizer closed on June 30, 2023. We granted certain registration rights to Pfizer under the Securities Purchase Agreement covering the resale of the shares. Unless otherwise agreed by Pfizer, we agreed to use the proceeds from the Pfizer Investment solely in connection with (i) the development program for our allogeneic anti-BCMA CAR-T cell therapy known as CB-011 that is being evaluated in our CaMMouflage clinical trial and/or (ii) any other single-targeted anti-BCMA CAR-T cell therapy using an anti-BCMA single-chain variable fragment owned or controlled by us (collectively, cell therapies described in clauses (i) and (ii) are referred to as a “BCMA Product Candidate”), for 36 months beginning on June 29, 2023. On June 29, 2023, in connection with the Pfizer Investment, we and Pfizer also entered into an Information Rights Agreement, having a thirty-six ( 36 )-month term. Under the Information Rights Agreement, we granted Pfizer a thirty ( 30 )-calendar day right of first negotiation (“ROFN”) if we commence or engage with any third party with respect to a potential grant of rights to develop and/or commercialize a BCMA Product Candidate, including, without limitation, a license agreement, a co-promotion/co-commercialization agreement, a profit share agreement, a joint venture agreement, or an asset sale agreement (a “Grant of Program Rights”). If we and Pfizer do not reach an agreement with respect to a Grant of Program Rights within the 30-day period, then we may pursue negotiations and enter into an agreement with any third party. If we and such third party do not reach agreement on the Grant of Program Rights within a specified time period, Pfizer’s right of first negotiation will be reinstated. Under the Information Rights Agreement, we also agreed to grant Pfizer the right to designate one representative to serve on our scientific advisory board (“SAB”). Through an information sharing committee, we provide calendar quarter updates to Pfizer regarding the development program for a BCMA Product Candidate. Additionally, we agreed to provide Pfizer access to any preclinical or interim or final clinical data (including raw data) and results generated as part of the development program for a BCMA Product Candidate at the same time that we provide such data to a third party (other than to our service providers or the FDA or other regulatory authorities), subject to certain confidentiality exceptions. On June 29, 2023, we and Pfizer also entered into a Voting Agreement, pursuant to which, for a period of 12 months, Pfizer agreed to cause our voting securities that Pfizer beneficially owns (within the meaning of Rules 13d-3 or 13d-5 under the Securities Exchange Act of 1934, as amended (“Exchange Act”)) in excess of 4.99 % of our then issued and outstanding voting securities to be voted (i) with respect to any matter directly relating to remuneration of directors, directors’ insurance, or indemnification or release from liability of directors, in a manner proportionally consistent with the votes properly cast for and against by holders of voting securities not beneficially owned by Pfizer, and (ii) with respect to any other matter in which Pfizer shall have the right to vote such voting securities, in accordance with the recommendation of our board of directors or any applicable committee thereof. We recorded the issuance of our common stock at its estimated fair value of $ 17.5 million, which reflects a discount for the lack of marketability of the shares. The remaining $ 7.5 million of the aggregate purchase price was allocated to the Information Rights Agreement, which represented a contract with a customer under ASC 606. We concluded that the information sharing committee represents the only performance obligation under the Information Rights Agreement. The ROFN does not provide Pfizer with a material right and is therefore not a performance obligation. We recognize revenue over time as the measure of progress which we believe best depicts the obligations to Pfizer. The information sharing committee will meet quarterly over the 36-month term of the Information Rights Agreement, which results in recognition of the transaction price over the 36-month term. F-25 Table of Contents During the twelve months ended December 31, 2023, we recognized $ 1.2 million of revenue from Pfizer. As of December 31, 2023, there was approximately $ 6.2 million of related party deferred revenue ($ 2.5 million included in current liabilities and $ 3.7 million included in long-term liabilities) related to our performance obligation to Pfizer. 8. Leases Operating Lease Obligations We lease laboratory and office space under noncancellable operating agreements. In March 2021, we entered into a ten-year lease agreement, which superseded and replaced our prior lease, as amended, for our corporate headquarters and the new lease included additional office and laboratory space located within the same building in Berkeley, California. This lease agreement contains a renewal option for an additional term of five years . In addition to base rent, we pay our share of operating expenses and taxes. In January 2022, we entered into a ten-and-a-half-year lease agreement for approximately 10,000 square feet of office and laboratory space in Berkeley, California, near our current corporate headquarters. In connection with signing this lease, we paid a deposit in the amount of $ 0.4 million to the lessor. This lease agreement contains an escalation clause for increased base rent over the term and a renewal option for an additional term of five years . In addition to base rent, we pay our share of operating expenses and taxes. To complete certain leasehold improvements, the lessor has agreed to provide us a tenant improvement allowance of $ 1.8 million. The leasehold improvements constructed are presented under property and equipment on our consolidated balance sheets and are depreciated on a straight-line basis over the shorter of remaining lease term or estimated useful life. The components of lease costs, which are included in our statements of operations and comprehensive loss, were as follows (in thousands): Years Ended December 31, 2023 2022 Operating lease cost (1) $ 7,628 $ 7,337 Short-term lease cost 250 83 Total lease cost $ 7,878 $ 7,420 (1) Includes $ 2.5 million and $ 2.2 million of variable lease cost related to operating expenses and taxes for the years ended December 31, 2023, and 2022, respectively. Supplemental information related to our leases was as follows (in thousands): Years Ended December 31, 2023 2022 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 3,732 $ 3,468 The following table summarizes the weighted-average remaining lease term and weighted-average discount rate for our corporate laboratory and office leases: Years Ended December 31, 2023 2022 Weighted-average remaining lease term (years) 7.4 8.3 Weighted-average discount rate 11.3 % 11.3 % F-26 Table of Contents The following table summarizes a maturity analysis of our operating lease liabilities showing the aggregate lease payments as of December 31, 2023: Year ending December 31: (in thousands) 2024 (1) $ 3,485 2025 4,475 2026 5,720 2027 5,922 2028 6,122 Thereafter 15,993 Total future undiscounted lease payments 41,717 Less imputed interest ( 14,609 ) Total discounted lease payments 27,108 Less current portion of lease liability ( 1,200 ) Noncurrent portion of lease liability $ 25,908 (1) Reflects an offset of $ 1.0 million related to incentives expected to be received in 2024. 9. Commitments and Contingencies Research, Manufacturing, and License Agreements We enter into various agreements in the ordinary course of business, such as those with CMOs, suppliers, CROs, clinical trial sites, licensors, assignors, and the like. These agreements provide for termination by either party in certain circumstances, generally with less than one-year notice and are, therefore, cancellable contracts and, if cancelled, are not anticipated to have a material effect on our consolidated financial condition, results of operations, or cash flows. Some of these agreements include contingent payments that will become payable if and when certain development, regulatory, clinical, and/or commercial milestones are achieved by us. As of December 31, 2023, the satisfaction and timing of such contingent payments is uncertain and is not reasonably estimable. Guarantees and Indemnifications In the normal course of business, we enter into agreements that contain a variety of representations and warranties and provide for certain indemnifications by us. Our exposure under these agreements is unknown because claims may be made against us in the future. To date, we have not paid any claims or been required to defend any action related to our indemnification obligations. As of each of December 31, 2023 and 2022, we did not have any material indemnification claims that were probable or reasonably possible, and consequently, we have not recorded related liabilities. Litigation From time to time, we may become involved in litigation arising in the ordinary course of business. We record a liability for such litigation when it is probable that future losses will be incurred and if such losses can be reasonably estimated. Significant judgment by us is required to determine both probability and the estimated amount. On April 11, 2023, a putative class action lawsuit was filed in the U.S. District Court for the Northern District of California against our company and certain of our officers and current and former members of our board of directors, B ergman v. Caribou Biosciences, Inc., et al. , Case Number 4:23-cv-01742-YGR (“Bergman Case”). The Bergman complaint challenges disclosures regarding our company’s business, operations, and prospects, specifically with respect to the alleged durability of CB-010’s therapeutic effect and the product candidate’s clinical and commercial prospects, in alleged violation of Sections 11 and 15 of the Securities Act of 1933, as amended (“Securities Act”) and Sections 10(b) and 20(a) of the Exchange Act. On September 18, 2023, plaintiffs filed an amended complaint adding the IPO underwriters as defendants and making substantially the same allegations as the original complaint. On November 14, 2023, we filed a motion to dismiss the amended complaint for failure to state a claim. Motion to dismiss briefing was completed on February 21, 2024, and oral argument on the motion is scheduled for April 23, 2024. We intend to vigorously defend the claims asserted against us. F-27 Table of Contents On March 22, 2023, a putative class action lawsuit was filed in Superior Court of the State of California for the County of Alameda against our company and certain of our officers and current and former members of our board of directors, Lowry v. Caribou Biosciences, Inc., et al. , Case Number T23-1084 (“Lowry Case”). The Lowry Case challenges disclosures regarding our company’s business, operations, and prospects, specifically with respect to the alleged durability of CB-010’s therapeutic effect and the product candidate’s clinical and commercial prospects, in alleged violation of Sections 11 and 15 of the Securities Act. The allegations and claims in the Lowry Case are substantially similar to the Securities Act claims asserted in the Bergman Case. On April 26, 2023, we filed a motion to stay the Lowry Case during the pendency of the parallel federal court litigation in the Bergman Case, and, on July 11, 2023, our motion to stay was denied. On September 11, 2023, plaintiff filed an amended complaint making substantially the same allegations as the original complaint. On November 9, 2023, we filed a motion to dismiss the amended complaint on the grounds that our certification of incorporation mandates that Securities Act claims against us be brought in federal court. On February 28, 2024, the court granted our motion to dismiss and ordered the case dismissed. 10. Common Stock Common stock reserved for future issuance, consisted of the following: As of December 31, 2023 As of December 31, 2022 Stock options, issued and outstanding 9,410,404 6,733,074 Stock options, authorized for future issuance 5,952,012 5,833,979 Stock available under our employee stock purchase plan 1,516,355 1,044,518 Unvested restricted stock units and performance-based restricted stock units 205,357 256,146 Total common stock reserved for future issuance 17,084,128 13,867,717 Shelf Registration Statement On August 9, 2022, we filed a shelf registration statement on Form S-3 (“Shelf Registration Statement”) with the SEC. The Shelf Registration Statement allows us to sell from time to time up to $ 400.0 million of common stock, preferred stock, debt securities, warrants, rights, or units comprised of any combination of these securities, for our own account in one or more offerings (including the $ 100.0 million of common stock reserved for our at-the-market equity offering program described below). The SEC declared the Shelf Registration Statement effective on August 16, 2022. The terms of any offering under the Shelf Registration Statement are established at the time of such offering as described in a prospectus supplement to the Shelf Registration Statement filed with the SEC prior to the completion of any such offering. In July and August 2023, we issued and sold a total of 22,115,384 shares of our common stock in an underwritten follow-on public offering at a price to the public of $ 6.50 per share, which included the full exercise of the underwriters’ right to purchase 2,884,615 additional shares of our common stock. The total gross proceeds from the offering were approximately $ 143.7 million ($ 134.4 million net of underwriting discounts and commissions and offering expenses). The shares were issued pursuant to the Shelf Registration Statement. At-the-market Equity Offering Program On August 9, 2022, we entered into an ATM Sales Agreement with Jefferies with respect to an at-the-market (“ATM”) equity offering program, pursuant to which, through Jefferies as sales agent, we may from time to time, sell shares of our common stock having an aggregate offering price of up to $ 100.0 million in gross proceeds under the Shelf Registration Statement. As of December 31, 2023, we sold 168,635 shares of our common stock under the ATM Sales Agreement at an average price per share of $ 7.32 for aggregate gross proceeds of $ 1.2 million ($ 1.0 million net of offering expenses). In February 2024, we sold 1,594,171 shares of our common stock under the ATM Sales Agreement, at an average price per share of $ 7.33 for aggregate gross proceeds of $ 11.7 million ($ 11.3 million, net of offering expenses). F-28 Table of Contents 11. Stock-Based Compensation Equity Incentive Plans In July 2021, our board of directors adopted and our stockholders approved the 2021 Equity Incentive Plan (“2021 Plan”) that became effective on July 22, 2021. We reserved 5,200,000 shares of common stock for issuance under the 2021 Plan. In addition, 934,562 shares available for issuance under the 2013 Equity Incentive Plan, adopted in 2013 and amended and restated in 2019, were transferred into the 2021 Plan. In addition, any shares subject to awards under the 2013 Plan that terminate, expire, or lapse for any reason without the delivery of shares, or are reacquired or withheld (or not issued) to satisfy a tax withholding obligation or the purchase or exercise price, will be added to the 2021 Plan. The 2021 Plan also provides that the number of shares initially reserved and available for issuance will automatically increase each January 1, beginning on January 1, 2022 and ending on January 1, 2031, by an amount equal to the lesser of (a) 5 % of the shares of common stock outstanding on the last day of the immediately preceding fiscal year, and (b) such smaller number of shares of stock as determined by our board of directors. No more than 56,000,000 shares of stock may be issued upon the exercise of incentive stock options under the 2021 Plan. Options under the 2021 Plan may be granted for periods of up to 10 years at exercise prices no less than the fair market value of our common stock on the date of grant; provided, however, that the exercise price of an incentive stock option granted to a 10 % stockholder may not be less than 110 % of the fair market value of the shares on the date of grant and such option may not be exercisable after the expiration of five years from the date of grant. The grant date fair market value of all awards made under the 2021 Plan and all cash compensation paid by us to any non-employee director for services as a director in any fiscal year may not exceed $ 750,000 , increased to $ 1,000,000 in the fiscal year of their initial service as a non-employee director. As of December 31, 2023, we had 5,952,012 shares available for issuance under the 2021 Plan. The following table summarizes stock option activity under our equity incentive plans during the year ended December 31, 2023 : Stock Options Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (years) Aggregate Intrinsic Value (in thousands) (1) Outstanding at December 31, 2021 6,757,591 $ 8.57 8.7 $ 50,085 Options granted 1,409,475 $ 8.81 Options exercised ( 696,913 ) $ 2.15 Options cancelled or forfeited ( 737,079 ) $ 11.00 Outstanding at December 31, 2022 6,733,074 $ 9.01 8.2 $ 8,203 Options granted 3,524,616 $ 5.70 Options exercised ( 228,264 ) $ 3.47 Options cancelled or forfeited ( 619,022 ) $ 7.17 Outstanding at December 31, 2023 9,410,404 $ 8.03 8.0 $ 6,432 Exercisable at December 31, 2023 4,440,139 $ 8.06 7.2 $ 4,547 Vested and expected to vest at December 31, 2023 9,410,404 $ 8.03 8.0 $ 6,432 (1) The aggregate intrinsic value is calculated as the difference between the stock option exercise price and the estimated fair value of the underlying common stock at the end of each reporting period referenced above. Grant Date Fair Value During the year ended December 31, 2023, we granted 3,524,616 stock options to employees with a weighted-average grant date fair value of $ 3.88 . During the year ended December 31, 2022, we granted 1,409,475 stock options to employees with a weighted-average grant date fair value of $ 5.82 . F-29 Table of Contents We estimated the fair value of each employee and stock option award on the grant date using the Black-Scholes option-pricing model based on the following assumptions: Years Ended December 31, 2023 2022 Volatility 74.1 % to 75.8 % 71.7 % to 74.2 % Expected term (in years) 5.0 to 6.0 5.5 to 6.0 Risk-free interest rate 3.5 % to 4.9 % 1.7 % to 4.4 % Expected dividend yield 0.0 % 0.0 % As of December 31, 2023, there was $ 25.8 million of unrecognized stock-based compensation expense related to employee and stock options that is expected to be recognized over a weighted-average period of 2.5 years. Restricted Stock Units During the year ended December 31, 2023, we granted 75,000 RSUs and no PSUs under the 2021 Plan. A summary of the status of and change in unvested RSUs and PSUs as of December 31, 2023 was as follows: Number of Shares Underlying Outstanding RSUs and PSUs Weighted-Average Grant Date Fair Value per RSU and PSU Unvested, January 1, 2022 — $ — Granted 259,839 10.07 Forfeited ( 3,693 ) 9.90 Unvested, December 31, 2022 256,146 $ 10.07 Granted 75,000 5.88 Vested ( 78,596 ) 10.04 Forfeited ( 47,193 ) 10.37 Unvested, December 31, 2023 205,357 $ 8.49 The PSUs were granted to our executive officers and will vest contingent upon the achievement of a clinical milestone for CB-010 during a performance period ending December 31, 2024, and an executive officer’s continued employment during the performance period. As of December 31, 2023, the achievement of this milestone was not considered probable and, therefore, no stock-based compensation was recorded. As of December 31, 2023, the total unrecognized stock-based compensation expense related to unvested RSUs was $ 0.8 million, which is expected to be recognized over the remaining weighted-average vesting period of one years. As of December 31, 2023, there was approximately $ 0.6 million of unrecognized stock-based compensation expense related to unvested PSUs. Employee Stock Purchase Plan (“ESPP”) In July 2021, our board of directors adopted and our stockholders approved the ESPP, which became effective on July 22, 2021. The ESPP is intended to qualify as an employee stock purchase plan under Section 423 of the Internal Revenue Code of 1986, as amended (“Tax Code”). We reserved 511,000 shares of our common stock for employee purchases under the ESPP. The number of shares of common stock reserved for issuance under the ESPP will be automatically increased each January 1, beginning on January 1, 2022 and ending on January 1, 2031 by an amount equal to the lesser of (a) 1 % of the shares of common stock outstanding on the last day of the immediately preceding fiscal year, and (b) such smaller number of shares of stock as determined by our board of directors; provided that the maximum number of shares that may be issued under the ESPP is 10,000,000 shares. The ESPP allows an eligible employee to purchase shares of our common stock at a discount through payroll deductions of up to 15 % of the employee’s eligible compensation. At the end of each purchase period, employees are able to purchase shares at 85 % of the lower of the fair market value of our common stock at the beginning of the offering period or at the end of each applicable offering period. F-30 Table of Contents We issued 207,567 shares of common stock under the ESPP as of December 31, 2023. We recorded $ 0.5 million and $ 0.3 million in accrued liabilities related to contributions withheld as of December 31, 2023 and December 31, 2022, respectively. Stock-Based Compensation Expense We recorded stock-based compensation expense related to employee equity-based awards grants in our consolidated statements of operations and comprehensive loss as follows (in thousands): Years Ended December 31, 2023 2022 Research and development $ 5,809 $ 4,345 General and administrative 7,941 7,371 Total $ 13,750 $ 11,716 The above stock-based compensation expense related to the following equity-based awards (in thousands): Years Ended December 31, 2023 2022 Stock options $ 12,392 $ 10,982 ESPP 574 310 RSUs 784 424 Total $ 13,750 $ 11,716 12. 401(k) Savings Plan In 2017, we established a defined-contribution savings plan under Section 401(k) of the Internal Revenue Code of 1986, as amended (“Tax Code”). Our 401(k) plan is available to all employees and allows participants to defer a portion of their annual compensation on a pretax basis subject to applicable laws. We also provide a 4 % match for employee contributions up to a certain limit. During the years ended December 31, 2023 and 2022, we contributed $ 1.1 million and $ 0.7 million, respectively, to our 401(k) plan. 13. Income Taxes We reported pre-tax book losses in the United States of $ 101.9 million and $ 99.4 million for the years ended December 31, 2023 and 2022, respectively. A reconciliation of the U.S. statutory income tax rate to our effective tax rate is as follows: Years 2023 2022 Federal income tax (benefit) at statutory rate ( 21 %) ( 21 %) State taxes, net of federal benefit ( 6 %) ( 8 %) Change in valuation allowance, federal 24 % 23 % Change in valuation allowance, state 6 % 8 % Stock-based compensation 1 % — % R&D tax credits, net of reserves ( 4 %) ( 3 %) Other — % 1 % Effective income tax rate — % — % F-31 Table of Contents For the years ended December 31, 2023 and 2022, our tax provision for (benefit from) income taxes consisted of the following (in thousands): Years 2023 2022 Current income taxes Federal $ — $ 163 State 15 2 Total current income tax expense 15 165 Deferred income taxes: Federal 1 — State 177 ( 95 ) Total deferred income tax (benefit) expense 178 ( 95 ) Total income tax expense $ 193 $ 70 Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. The following table presents significant components of our deferred tax assets and liabilities as of December 31, 2023 and 2022 (in thousands): 2023 2022 Deferred tax assets: NOL and tax attributes $ 51,688 $ 37,120 Accrued expenses and reserve 2,158 1,539 Deferred revenue and expenses 697 7,493 State income taxes 7 7 Capitalized license and patent costs 1,456 1,311 Capitalized research and development cost 37,196 18,462 Lease liabilities 7,098 8,058 Stock-based compensation 4,625 2,921 Total deferred tax assets 104,925 76,911 Valuation allowance ( 96,166 ) ( 66,408 ) Net deferred tax assets 8,759 10,503 Deferred tax liabilities: Investments in equity securities ( 1,948 ) ( 1,713 ) Lease right of use assets ( 5,808 ) ( 7,037 ) Fixed assets ( 1,560 ) ( 2,134 ) Total deferred tax liabilities ( 9,316 ) ( 10,884 ) Net deferred tax assets (liabilities) $ ( 557 ) $ ( 381 ) We have evaluated the positive and negative evidence bearing upon the realizability of its deferred tax assets. As of December 31, 2022, a valuation allowance of $ 66.4 million was recorded against our deferred tax assets. As of December 31, 2023, our deferred tax assets were primarily the result of historical federal and state net operating loss (“NOL”) and tax credits, deferred revenue and expenses, capitalized research costs and the net of lease right of use assets and liabilities. As of December 31, 2023, a valuation allowance of $ 96.2 million was recorded against our deferred tax assets. F-32 Table of Contents As of December 31, 2023, we had federal NOL carryforwards of $ 103.8 million, which do not expire. As of December 31, 2023, we had state NOL carryforwards of $ 172.7 million, which may be available to offset future state income, and which expire at various years beginning with 2036. As of December 31, 2023, we generated federal tax credit carryforwards of $ 14.2 million, which will begin to expire in 2037. As of December 31, 2023, we had state credit carryforwards of $ 5.6 million available to reduce future tax liabilities, which do not expire. Beginning January 1, 2022, the Tax Cuts and Jobs Act of 2017 eliminated the option to deduct research and development expenditures in the current year and requires taxpayers to capitalize and amortize pursuant to Section 174 of the Tax Code. As a result, we have capitalized research and development costs of $ 102.6 million and $ 93.9 million for the years ended December 31, 2023 and 2022, respectively. We will amortize these costs for tax purposes over five years if the research and development was performed in the United States and over 15 years if the research and development was performed outside the United States. Under Section 382 of the Tax Code, the ability to utilize NOL carryforwards or other tax attributes, such as research tax credits, in any taxable year may be limited if we have experienced an “ownership change.” Generally, a Section 382 ownership change occurs if there is a cumulative increase of more than 50 percentage points in the stock ownership of one or more stockholders or groups of stockholders who own at least 5 % of a corporation’s stock within a specified testing period. Similar rules may apply under state tax laws. As a result of our analysis, we believe that there have been three ownership changes under Section 382; however, none of our tax attributes are expected to have permanent limitations. We may experience ownership changes as a result of future financing or other changes in the stock ownership. The following table summarizes the activity related to our unrecognized tax benefits for the two years ended December 31, 2023 (in thousands): Unrecognized tax benefits—December 31, 2021 $ 2,202 Increases related to current year tax positions 847 Increases related to prior year tax positions — Decreases related to prior year tax positions ( 250 ) Unrecognized tax benefits—December 31, 2022 2,799 Increases related to current year tax positions 1,269 Increases related to prior year tax positions 123 Decreases related to prior year tax positions ( 98 ) Decreases related to lapse of statutes — Unrecognized tax benefits—December 31, 2023 $ 4,093 As of December 31, 2023, no amount of unrecognized tax benefits, if recognized, would affect the effective tax rate. We do not expect a significant change to our unrecognized tax benefits over the next 12 months. The unrecognized tax benefits may increase or change during the next year for items that arise in the ordinary course of business. We recognize interest and penalties related to uncertain tax positions in income tax expense. As of December 31, 2023 and 2022, we had no accrued interest or penalties related to uncertain tax positions and no amounts have been recognized in our consolidated statements of operations and comprehensive loss. We file our federal and state income tax returns with varying statutes of limitations. Our tax years from 2012 through 2022 will remain open to examination due to the carryover of the unused NOLs and tax credits. There are no ongoing examinations by taxing authorities at this time. The following table shows the change in deferred tax valuation for the periods indicated: F-33 Table of Contents 2023 2022 Beginning balance, January 1 66,408 34,521 Change charged to expense 29,758 31,887 Ending balance, December 31 96,166 66,408 14. Net Loss Per Share The following table sets forth the computation of the basic and diluted net loss per share (in thousands, except share and per share amounts): Years Ended December 31, 2023 2022 Numerator: Net loss $ ( 102,070 ) $ ( 99,421 ) Denominator: Weighted-average common shares outstanding used to compute net loss per share, basic and diluted 73,807,597 60,801,133 Net loss per share, basic and diluted $ ( 1.38 ) $ ( 1.64 ) Because we were in a net loss position for all periods presented, basic net loss per share is the same as diluted net loss per share for all periods, as the inclusion of all common stock equivalents outstanding would have been anti-dilutive. Potentially dilutive securities that were not included in the diluted per share calculations because they would be anti-dilutive were as follows: As of December 31, 2023 As of December 31, 2022 Stock options outstanding 9,410,404 6,733,074 RSUs issued and outstanding 153,000 256,146 Shares available under ESPP 134,276 49,109 9,697,680 7,038,329 15. Subsequent Events In February 2024, we sold 1,594,171 shares of our common stock under the ATM Sales Agreement, at an average price per share of $ 7.33 for aggregate gross proceeds of $ 11.7 million ($ 11.3 million, net of offering expenses). On February 28, 2024, the Superior Court of the State of California for the County of Alameda granted our motion to dismiss the putative class action lawsuit filed against our company and certain of our officers and current and former members of our board of directors, Lowry v. Caribou Biosciences, Inc., et al. , Case Number T23-1084 (“Lowry Case”), and the court ordered the case dismissed. F-34