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1. Organization and Description of the Business Organization Abpro Holdings, Inc. and its subsidiaries, (the “Company”) is a biotechnology company headquartered in Burlington, Massachusetts, dedicated to developing next-generation antibody therapeutics to improve the lives of patients with severe and life-threatening diseases. The Company is focused on the development of novel antibodies using its proprietary discovery and engineering platforms, primarily in the areas of immuno-oncology, ophthalmology and infectious disease. On November 13, 2024 (the “Closing Date”), Abpro Corporation (“Legacy Abpro”) completed the merger with Atlantic Coastal Acquisition Corp. II (“ACAB”) (the “Merger”). At the Closing Date, ACAB changed its name to “Abpro Holdings, Inc.” Reverse Stock Split On October 16, 2025, the Company filed with the Delaware Secretary of State a Certificate of Amendment to the Certificate of Incorporation of the Company (the “Certificate of Amendment”), which became effective on October 31, 2025 (the “Effective Time”), to effect a one-for-thirty (1:30) reverse stock split (the “Reverse Stock Split”), of the shares of the Company’s common stock, par value $0.0001 per share. The Reverse Stock Split was approved by the Company’s stockholders at the 2025 annual meeting of the stockholders on October 10, 2025. The Company’s common stock began trading on a reverse stock split-adjusted basis upon market opening on November 3, 2025. As a result of the Reverse Stock Split, every 30 shares of issued and outstanding common stock were automatically combined into one (1) issued and outstanding share of common stock, without any change in the par value per share. No fractional shares were issued as a result of the Reverse Stock Split. Instead, stockholders who otherwise would have been entitled to receive fractional shares because they held a number of shares not evenly divisible by the Reverse Stock Split ratio will be entitled to receive an additional fraction of a share of common stock to round up to the next whole share. All of the Company’s historical share and per share information related to issued and outstanding common stock, restricted stock units, and options and warrants exercisable for common stock in these financial statements have been adjusted, on a retroactive basis, to reflect this 1:30 reverse stock split. Risks and Uncertainties The Company is subject to risks and uncertainties common to early-stage companies in the biotechnology industry, including, but not limited to, development by competitors of more advanced or effective therapies, dependence on key executives, protection of and dependence on proprietary technology, compliance with government regulations and ability to secure additional capital to fund operations. Programs currently under development will require significant additional research and development efforts, including preclinical and clinical testing and regulatory approval prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel and infrastructure, and extensive compliance-reporting capabilities. Even if the Company’s product development efforts are successful, it is uncertain when, if ever, the Company will realize significant revenue from product sales. Going Concern The Company is required to evaluate whether there are conditions or events, considered in the aggregate, that raise substantial doubt about its ability to continue as a going concern within one year after the date that the condensed consolidated financial statements are issued. Through March 31, 2026, the Company has funded its operations mainly through equity and debt financings, including the proceeds from the issuance of shares under the SEPA (see Note 10), and to a lesser extent, payments received in connection with collaboration and license agreements. As of March 31, 2026 and December 31, 2025, the Company had an accumulated deficit of $120,023 and $118,995, respectively. The Company’s net loss was $1,028 and $3,887 for the three months ended March 31, 2026 and 2025, respectively. Substantially all of the Company’s net losses resulted from costs incurred in connection with the Company’s research and development programs and from general and administrative costs associated with the Company’s operations. The Company expects to incur substantial operating losses and negative cash flows from operations for the foreseeable future as the Company advances its product candidates. On April 2, 2025, the Company received written notice from the Listing Qualifications Department staff (the “Staff”) of the Nasdaq Stock Market (“Nasdaq”) notifying the Company that, based on the closing bid price of the Company’s common stock for the last 30 consecutive business days, the Company no longer complies with the minimum bid price requirement for continued listing on The Nasdaq Stock Market LLC. Nasdaq Listing Rule 5450(a)(1) requires listed securities to maintain a minimum bid price of $1.00 per share (the “Minimum Bid Price Requirement”), and Nasdaq Listing Rule 5810(c)(3)(A) provides that a failure to meet the Minimum Bid Price Requirement exists if the deficiency continues for a period of 30 consecutive business days. On February 18, 2026, the Company received written notification from the Panel stating that, due to the Company not having met the terms of the Panel’s November 10, 2025 decision that the Company demonstrate compliance with the minimum equity standard requirement under Nasdaq Listing Rule 5550(b)(1) by February 16, 2026, the Company’s securities were to be delisted from Nasdaq. The trading of the Company’s common stock was suspended at the open of trading on NASDAQ on February 23, 2026 and the Company’s securities now trade on the OTCQB, Pink Limited tier of the OTC Markets under the ticker symbol “ABPO”. The Company was provided fifteen (15) days from receipt of the aforementioned notice of the Panel’s decision to request that the Nasdaq Listing and Hearing Review Council (the “Council”) review the decision. The delisting does not affect the Company’s operations, but may have, among other material adverse effects, an adverse impact on the liquidity and market price of the Common Stock and on the Company’s ability to raise capital, including under the SEPA (see Note 10) and on favorable terms, if at all, in the future. On March 18, 2026, the Company formally appealed the delisting determination and is currently expecting the response in June 2026. As of March 31, 2026, the Company had cash of $5,398. Due to its current liabilities, the cash available to the Company will not be sufficient to allow the Company to operate for at least 12 months from the date these unaudited condensed consolidated financial statements are issued. The future viability of the Company is largely dependent on its ability to raise additional capital to finance its operations. The Company expects to seek additional funding through equity and debt financings, collaboration agreements and research grants. If the Company is unable to obtain funding, the Company could be forced to delay, reduce or eliminate its research and development programs, product portfolio expansion or commercialization efforts, which could adversely affect its business prospects. Accordingly, based on the considerations discussed above, management has concluded there is substantial doubt as to the Company’s ability to continue as a going concern within one year after the date these unaudited condensed consolidated financial statements are issued. The Company plans to continue to fundraise, as well as seek alternate revenues from collaboration and license agreements. If adequate funds are not available, the Company may be required to initiate steps to slow cash burn, extending the cash runway until financing can be secured. These unaudited condensed consolidated financial statements do not include any adjustments with respect to the carrying amounts of assets and liabilities and their classification that might result from the outcome of this uncertainty.

1:30

0.0001

30 30

1:30

P1Y

-120023000

-118995000

-1028000

-3887000

P30D 1 P30D P15D

5398000

P1Y

2. Summary of Significant Accounting Policies Basis of Presentation The unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and the applicable rules and regulations of the U.S. Securities and Exchange Commission (“SEC”). The accompanying unaudited condensed consolidated financial statements include all of the accounts of the Company and its subsidiaries, Abpro Corporation and AbMed Corporation (“AbMed”). All intercompany balances and transactions have been eliminated in consolidation. Certain prior period amounts have been reclassified to conform to the current year presentation, including the reclassification of amounts in the balance sheet for prepaid expenses and other current assets and notes payable with respect to the insurance premium financing agreement (see Note 9), with no material impact on the condensed consolidated financial statements. Use of Estimates The preparation of the condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and judgments that affect the amounts reported in the condensed consolidated financial statements and accompanying notes. Significant estimates in these condensed consolidated financial statements include share-based compensation expense, fair value of warrants, pre-clinical and clinical accrued expenses, valuation and realizability of deferred tax assets and the ability to continue as a going concern. On an ongoing basis, the Company evaluates its estimates, judgments, and methodologies. The Company bases its estimates on historical experience and on various other assumptions believed to be reasonable. Due to the inherent uncertainty involved in making estimates, actual results could differ materially from those estimates. Unaudited Interim Condensed Consolidated Financial Statements The accompanying interim condensed consolidated financial statements and the related footnote disclosures are unaudited. These unaudited interim financial statements have been prepared on the same basis as the audited financial statements, and in management’s opinion, include all adjustments, consisting of only normal recurring adjustments, necessary for the fair statement of the Company’s financial position as of March 31, 2026 and its results of operations and cash flows for the three months ended March 31, 2026 and 2025. The results of operations for the three months ended March 31, 2026 are not necessarily indicative of the results to be expected for the year ended December 31, 2026 or any other period. The December 31, 2025 year-end condensed consolidated balance sheet was derived from audited annual financial statements but does not include all disclosures from the annual financial statements. Certain information and footnote disclosures normally included in consolidated financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to the rules and regulations of the SEC. Accordingly, these condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements for the year ended December 31, 2025 and the related notes included in the Company’s Annual Report on Form 10-K, filed with the SEC on April 15, 2026 (the “Annual Report”), which provides a more complete discussion of the Company’s accounting policies and certain other information. There have been no significant changes to the significant accounting policies disclosed in Note 2 of the audited consolidated financial statements as of and for the year ended December 31, 2025 included in the Company’s Annual Report. Segment Reporting ASC Topic No. 280, Segment Reporting (“ASC 280”), establishes standards for the way that public business entities report information about operating segments in their annual consolidated financial statements and requires that those entities report selected information about operating segments in interim financial reports. ASC 280 also establishes standards for related disclosures about products and services, geographic areas and major customers. The Company’s business segments are based on the organization structure used by the chief operating decision maker (“CODM”) for making operating and investment decisions and for assessing performance. In accordance with ASC 280, the Company has determined that it operates as a single reportable segment, which is the business of development of novel antibodies, primarily in the areas of immuno-oncology, ophthalmology and infectious disease. The financial results of the Company’s operations are managed and reported to the Chief Executive Officer, who is considered the Company’s CODM, on a consolidated basis. The CODM assesses performance and allocates resources based on the Company’s consolidated statements of operations, and key components and processes of the Company’s operations are managed centrally. Segment asset information is not used by the CODM to allocate resources. The Chief Executive Officer uses operating losses and cash flows from operating activities to evaluate performance of the operating segment assets in deciding how to allocate the cash resources. Significant expenses presented to the CODM include research and development expenses, general and administrative expenses, and interest expenses, which are each separately presented on the Company’s condensed consolidated statements of operations.Net Loss Per Share Basic net loss per share attributable to common stockholders is computed by dividing net loss attributable to common stockholders by the weighted-average number of common stock shares outstanding during the period without consideration of potentially dilutive common stock. Diluted net loss per share attributable to common stockholders reflects the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock or resulted in the issuance of common stock that then shared in the earnings of the Company unless the inclusion of such shares would be anti-dilutive. As the Company has incurred losses for the three months ended March 31, 2026 and 2025, basic and diluted net losses per share are the same for all periods presented. The following table presents the potentially dilutive shares that were excluded from the computation of diluted net loss per share of common stock attributable to common stockholders, because their effect was anti-dilutive: <table cellpadding="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif; border-spacing: 0px;"> <tr style="vertical-align: bottom"> <td style="text-align: justify"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="6" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">March 31,</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td></tr> <tr style="vertical-align: bottom"> <td style="text-align: justify"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">2026</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">2025</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 76%; text-align: justify">Warrants</td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left"> </td><td style="width: 9%; text-align: right">990,000</td><td style="width: 1%; text-align: left"> </td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left"> </td><td style="width: 9%; text-align: right">990,000</td><td style="width: 1%; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify">Stock options</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">192,221</td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">231,758</td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: justify">Convertible Notes</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-63">-</div></td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">526,316</td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify; padding-bottom: 1.5pt">Unvested restricted stock units</td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right">24,503</td><td style="padding-bottom: 1.5pt; text-align: left"> </td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right">185</td><td style="padding-bottom: 1.5pt; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: justify; padding-bottom: 4pt">Total</td><td style="padding-bottom: 4pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left"> </td><td style="border-bottom: Black 4pt double; text-align: right">1,206,724</td><td style="padding-bottom: 4pt; text-align: left"> </td><td style="padding-bottom: 4pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left"> </td><td style="border-bottom: Black 4pt double; text-align: right">1,748,258</td><td style="padding-bottom: 4pt; text-align: left"> </td></tr> </table> Recently Issued Accounting Pronouncements On November 4, 2024, the FASB issued ASU 2024-03, Accounting Standards Update 2024-03, Income Statement-Reporting Comprehensive Income-Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses to improve financial reporting by requiring that public business entities disclose additional information about specific expense categories in the notes to financial statements at interim and annual reporting periods. The amendments in this ASU do not change or remove current expense disclosure requirements; however, the amendments affect where such information appears in the notes to financial statements because entities are required to include certain current disclosures in the same tabular format disclosure as the other disaggregation requirements in the amendments. This ASU is effective for annual reporting periods beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027. Early adoption is permitted. The Company is currently evaluating the potential impact that the adoption of this standard will have on its financial statements. Management does not believe that any additional recently issued, but not yet effective, accounting standards, if currently adopted, would have a material impact on the Company’s financial statements.

Basis of PresentationThe unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and the applicable rules and regulations of the U.S. Securities and Exchange Commission (“SEC”). The accompanying unaudited condensed consolidated financial statements include all of the accounts of the Company and its subsidiaries, Abpro Corporation and AbMed Corporation (“AbMed”). All intercompany balances and transactions have been eliminated in consolidation.Certain prior period amounts have been reclassified to conform to the current year presentation, including the reclassification of amounts in the balance sheet for prepaid expenses and other current assets and notes payable with respect to the insurance premium financing agreement (see Note 9), with no material impact on the condensed consolidated financial statements.

Use of EstimatesThe preparation of the condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and judgments that affect the amounts reported in the condensed consolidated financial statements and accompanying notes. Significant estimates in these condensed consolidated financial statements include share-based compensation expense, fair value of warrants, pre-clinical and clinical accrued expenses, valuation and realizability of deferred tax assets and the ability to continue as a going concern. On an ongoing basis, the Company evaluates its estimates, judgments, and methodologies. The Company bases its estimates on historical experience and on various other assumptions believed to be reasonable. Due to the inherent uncertainty involved in making estimates, actual results could differ materially from those estimates.

Unaudited Interim Condensed Consolidated Financial StatementsThe accompanying interim condensed consolidated financial statements and the related footnote disclosures are unaudited. These unaudited interim financial statements have been prepared on the same basis as the audited financial statements, and in management’s opinion, include all adjustments, consisting of only normal recurring adjustments, necessary for the fair statement of the Company’s financial position as of March 31, 2026 and its results of operations and cash flows for the three months ended March 31, 2026 and 2025. The results of operations for the three months ended March 31, 2026 are not necessarily indicative of the results to be expected for the year ended December 31, 2026 or any other period. The December 31, 2025 year-end condensed consolidated balance sheet was derived from audited annual financial statements but does not include all disclosures from the annual financial statements.Certain information and footnote disclosures normally included in consolidated financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to the rules and regulations of the SEC. Accordingly, these condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements for the year ended December 31, 2025 and the related notes included in the Company’s Annual Report on Form 10-K, filed with the SEC on April 15, 2026 (the “Annual Report”), which provides a more complete discussion of the Company’s accounting policies and certain other information.There have been no significant changes to the significant accounting policies disclosed in Note 2 of the audited consolidated financial statements as of and for the year ended December 31, 2025 included in the Company’s Annual Report.

Segment ReportingASC Topic No. 280, Segment Reporting (“ASC 280”), establishes standards for the way that public business entities report information about operating segments in their annual consolidated financial statements and requires that those entities report selected information about operating segments in interim financial reports. ASC 280 also establishes standards for related disclosures about products and services, geographic areas and major customers. The Company’s business segments are based on the organization structure used by the chief operating decision maker (“CODM”) for making operating and investment decisions and for assessing performance.In accordance with ASC 280, the Company has determined that it operates as a single reportable segment, which is the business of development of novel antibodies, primarily in the areas of immuno-oncology, ophthalmology and infectious disease. The financial results of the Company’s operations are managed and reported to the Chief Executive Officer, who is considered the Company’s CODM, on a consolidated basis. The CODM assesses performance and allocates resources based on the Company’s consolidated statements of operations, and key components and processes of the Company’s operations are managed centrally. Segment asset information is not used by the CODM to allocate resources. The Chief Executive Officer uses operating losses and cash flows from operating activities to evaluate performance of the operating segment assets in deciding how to allocate the cash resources. Significant expenses presented to the CODM include research and development expenses, general and administrative expenses, and interest expenses, which are each separately presented on the Company’s condensed consolidated statements of operations.

The CODM assesses performance and allocates resources based on the Company’s consolidated statements of operations, and key components and processes of the Company’s operations are managed centrally. Segment asset information is not used by the CODM to allocate resources. The Chief Executive Officer uses operating losses and cash flows from operating activities to evaluate performance of the operating segment assets in deciding how to allocate the cash resources. Significant expenses presented to the CODM include research and development expenses, general and administrative expenses, and interest expenses, which are each separately presented on the Company’s condensed consolidated statements of operations.

Net Loss Per ShareBasic net loss per share attributable to common stockholders is computed by dividing net loss attributable to common stockholders by the weighted-average number of common stock shares outstanding during the period without consideration of potentially dilutive common stock. Diluted net loss per share attributable to common stockholders reflects the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock or resulted in the issuance of common stock that then shared in the earnings of the Company unless the inclusion of such shares would be anti-dilutive. As the Company has incurred losses for the three months ended March 31, 2026 and 2025, basic and diluted net losses per share are the same for all periods presented.The following table presents the potentially dilutive shares that were excluded from the computation of diluted net loss per share of common stock attributable to common stockholders, because their effect was anti-dilutive:<table cellpadding="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif; border-spacing: 0px;"> <tr style="vertical-align: bottom"> <td style="text-align: justify"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="6" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">March 31,</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td></tr> <tr style="vertical-align: bottom"> <td style="text-align: justify"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">2026</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">2025</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 76%; text-align: justify">Warrants</td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left"> </td><td style="width: 9%; text-align: right">990,000</td><td style="width: 1%; text-align: left"> </td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left"> </td><td style="width: 9%; text-align: right">990,000</td><td style="width: 1%; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify">Stock options</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">192,221</td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">231,758</td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: justify">Convertible Notes</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-63">-</div></td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">526,316</td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify; padding-bottom: 1.5pt">Unvested restricted stock units</td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right">24,503</td><td style="padding-bottom: 1.5pt; text-align: left"> </td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right">185</td><td style="padding-bottom: 1.5pt; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: justify; padding-bottom: 4pt">Total</td><td style="padding-bottom: 4pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left"> </td><td style="border-bottom: Black 4pt double; text-align: right">1,206,724</td><td style="padding-bottom: 4pt; text-align: left"> </td><td style="padding-bottom: 4pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left"> </td><td style="border-bottom: Black 4pt double; text-align: right">1,748,258</td><td style="padding-bottom: 4pt; text-align: left"> </td></tr> </table>

The following table presents the potentially dilutive shares that were excluded from the computation of diluted net loss per share of common stock attributable to common stockholders, because their effect was anti-dilutive: <table cellpadding="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif; border-spacing: 0px;"> <tr style="vertical-align: bottom"> <td style="text-align: justify"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="6" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">March 31,</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td></tr> <tr style="vertical-align: bottom"> <td style="text-align: justify"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">2026</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">2025</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 76%; text-align: justify">Warrants</td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left"> </td><td style="width: 9%; text-align: right">990,000</td><td style="width: 1%; text-align: left"> </td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left"> </td><td style="width: 9%; text-align: right">990,000</td><td style="width: 1%; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify">Stock options</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">192,221</td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">231,758</td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: justify">Convertible Notes</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-63">-</div></td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">526,316</td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify; padding-bottom: 1.5pt">Unvested restricted stock units</td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right">24,503</td><td style="padding-bottom: 1.5pt; text-align: left"> </td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right">185</td><td style="padding-bottom: 1.5pt; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: justify; padding-bottom: 4pt">Total</td><td style="padding-bottom: 4pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left"> </td><td style="border-bottom: Black 4pt double; text-align: right">1,206,724</td><td style="padding-bottom: 4pt; text-align: left"> </td><td style="padding-bottom: 4pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left"> </td><td style="border-bottom: Black 4pt double; text-align: right">1,748,258</td><td style="padding-bottom: 4pt; text-align: left"> </td></tr> </table>

990000

192221

231758

526316

24503

185

1206724

1748258

Recently Issued Accounting PronouncementsOn November 4, 2024, the FASB issued ASU 2024-03, Accounting Standards Update 2024-03, Income Statement-Reporting Comprehensive Income-Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses to improve financial reporting by requiring that public business entities disclose additional information about specific expense categories in the notes to financial statements at interim and annual reporting periods. The amendments in this ASU do not change or remove current expense disclosure requirements; however, the amendments affect where such information appears in the notes to financial statements because entities are required to include certain current disclosures in the same tabular format disclosure as the other disaggregation requirements in the amendments. This ASU is effective for annual reporting periods beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027. Early adoption is permitted. The Company is currently evaluating the potential impact that the adoption of this standard will have on its financial statements.Management does not believe that any additional recently issued, but not yet effective, accounting standards, if currently adopted, would have a material impact on the Company’s financial statements.

3. Accrued Expenses Accrued expenses consisted of the following: <table cellpadding="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif; border-spacing: 0px;"> <tr style="vertical-align: bottom"> <td> </td><td style="font-weight: bold"> </td> <td colspan="2" style="font-weight: bold; text-align: center">March 31,</td><td style="font-weight: bold"> </td><td style="font-weight: bold"> </td> <td colspan="2" style="font-weight: bold; text-align: center">December 31,</td><td style="font-weight: bold"> </td></tr> <tr style="vertical-align: bottom"> <td> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">2026</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">2025</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 76%; text-align: left">Accrued salaries and wages </td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left">$</td><td style="width: 9%; text-align: right">928</td><td style="width: 1%; text-align: left"> </td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left">$</td><td style="width: 9%; text-align: right">1,114</td><td style="width: 1%; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: left">Accrued professional fees </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">1,054</td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">1,154</td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: left">Accrued issuance costs </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">585</td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">77</td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: left">Accrued interest </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">277</td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">275</td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: left">BOD compensation </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">305</td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">191</td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: left; padding-bottom: 1.5pt">Other accrued expenses </td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right">722</td><td style="padding-bottom: 1.5pt; text-align: left"> </td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right">1,064</td><td style="padding-bottom: 1.5pt; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: left; padding-bottom: 4pt">Total accrued expenses </td><td style="padding-bottom: 4pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left">$</td><td style="border-bottom: Black 4pt double; text-align: right">3,871</td><td style="padding-bottom: 4pt; text-align: left"> </td><td style="padding-bottom: 4pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left">$</td><td style="border-bottom: Black 4pt double; text-align: right">3,875</td><td style="padding-bottom: 4pt; text-align: left"> </td></tr> </table>

Accrued expenses consisted of the following: <table cellpadding="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif; border-spacing: 0px;"> <tr style="vertical-align: bottom"> <td> </td><td style="font-weight: bold"> </td> <td colspan="2" style="font-weight: bold; text-align: center">March 31,</td><td style="font-weight: bold"> </td><td style="font-weight: bold"> </td> <td colspan="2" style="font-weight: bold; text-align: center">December 31,</td><td style="font-weight: bold"> </td></tr> <tr style="vertical-align: bottom"> <td> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">2026</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">2025</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 76%; text-align: left">Accrued salaries and wages </td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left">$</td><td style="width: 9%; text-align: right">928</td><td style="width: 1%; text-align: left"> </td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left">$</td><td style="width: 9%; text-align: right">1,114</td><td style="width: 1%; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: left">Accrued professional fees </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">1,054</td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">1,154</td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: left">Accrued issuance costs </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">585</td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">77</td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: left">Accrued interest </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">277</td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">275</td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: left">BOD compensation </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">305</td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">191</td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: left; padding-bottom: 1.5pt">Other accrued expenses </td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right">722</td><td style="padding-bottom: 1.5pt; text-align: left"> </td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right">1,064</td><td style="padding-bottom: 1.5pt; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: left; padding-bottom: 4pt">Total accrued expenses </td><td style="padding-bottom: 4pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left">$</td><td style="border-bottom: Black 4pt double; text-align: right">3,871</td><td style="padding-bottom: 4pt; text-align: left"> </td><td style="padding-bottom: 4pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left">$</td><td style="border-bottom: Black 4pt double; text-align: right">3,875</td><td style="padding-bottom: 4pt; text-align: left"> </td></tr> </table>

928000

1114000

1054000

1154000

585000 77000 277000 275000 305000 191000

722000

1064000

3871000

3875000

4. Fair Value Measurements The following table presents information about the Company’s assets and liabilities that are measured at fair value on a recurring basis as of March 31, 2026 and December 31, 2025, and indicates the fair value hierarchy of the valuation inputs the Company’s utilized to determine such fair value: <table cellpadding="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif; border-spacing: 0px;"> <tr style="vertical-align: bottom"> <td style="text-align: justify"> </td><td> </td> <td colspan="2" style="text-align: justify"> </td><td> </td><td style="font-weight: bold"> </td> <td colspan="2" style="font-weight: bold; text-align: center">March 31,</td><td style="font-weight: bold"> </td><td style="font-weight: bold"> </td> <td colspan="2" style="font-weight: bold; text-align: center">December 31,</td><td style="font-weight: bold"> </td></tr> <tr style="vertical-align: bottom"> <td style="font-weight: bold; text-align: justify; border-bottom: Black 1.5pt solid">Description</td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">Level</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">2026</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">2025</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td></tr> <tr style="vertical-align: bottom"> <td style="text-align: justify">Assets:</td><td> </td> <td colspan="2" style="text-align: justify"> </td><td> </td><td> </td> <td colspan="2" style="text-align: justify"> </td><td> </td><td> </td> <td colspan="2" style="text-align: justify"> </td><td> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 64%; text-align: justify">SEPA put rights asset (Note 10)</td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left"> </td><td style="width: 9%; text-align: center">3</td><td style="width: 1%; text-align: left"> </td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left">$</td><td style="width: 9%; text-align: right"><div style="-sec-ix-hidden: hidden-fact-65">-</div></td><td style="width: 1%; text-align: left"> </td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left">$</td><td style="width: 9%; text-align: right">155</td><td style="width: 1%; text-align: left"> </td></tr> </table> The fair value of the SEPA Put Rights was estimated as the sum of the fair values of the put rights under each assumed advance notice over the term of the SEPA. The number of shares under each advance notice was based on the historical trading volumes of the Company’s common stock taking into account various beneficial ownership and daily volume limitations. The trading of the Company’s common stock was suspended at the open of trading on NASDAQ on February 23, 2026 and as a result, the Company is unable to comply with the registration and listing requirements to raise capital under the SEPA. As a result, as of March 31, 2026, the fair value of SEPA put rights asset was deemed de minimis. As of December 31, 2025, the fair value of the put rights under each advance notice was estimated using the Black Scholes model, incorporating the following assumptions: <table cellpadding="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif; border-spacing: 0px;"> <tr style="vertical-align: bottom"> <td style="text-align: justify"> </td><td style="font-weight: bold"> </td> <td colspan="2" style="font-weight: bold; text-align: center">December 31,</td><td style="font-weight: bold"> </td></tr> <tr style="vertical-align: bottom"> <td style="text-align: justify"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">2025</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 88%; text-align: justify">Stock price</td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left">$</td><td style="width: 9%; text-align: right">4.23</td><td style="width: 1%; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify">Risk-free interest rate</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">3.5 to 3.7</td><td style="text-align: left">%</td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: justify">Exercise price</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">4.06</td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify">Expected term (in years)</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">0.25 to 0.92</td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: justify">Expected volatility</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"> 78-86</td><td style="text-align: left">%</td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify">Expected dividend yield</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">0</td><td style="text-align: left">%</td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: justify">Number of shares under each advance notice</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">27,100</td><td style="text-align: left"> </td></tr> </table> The changes in the fair value of Level 3 financial assets and liabilities for the three months ended March 31, 2026 are as follows: <table cellpadding="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif; border-spacing: 0px;"> <tr style="vertical-align: bottom"> <td style="padding-bottom: 1.5pt; text-align: justify"> </td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td> <td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center">SEPA Put Rights Asset</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 88%; text-align: justify">Fair value as of January 1, 2026</td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left">$</td><td style="width: 9%; text-align: right">96</td><td style="width: 1%; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="padding-bottom: 1.5pt; text-align: justify">Change in fair value</td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right">(96</td><td style="padding-bottom: 1.5pt; text-align: left">)</td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="padding-bottom: 4pt; text-align: justify">Fair value as of March 31, 2026</td><td style="padding-bottom: 4pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left">$</td><td style="border-bottom: Black 4pt double; text-align: right">0</td><td style="padding-bottom: 4pt; text-align: left"> </td></tr> </table>

The following table presents information about the Company’s assets and liabilities that are measured at fair value on a recurring basis as of March 31, 2026 and December 31, 2025, and indicates the fair value hierarchy of the valuation inputs the Company’s utilized to determine such fair value: <table cellpadding="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif; border-spacing: 0px;"> <tr style="vertical-align: bottom"> <td style="text-align: justify"> </td><td> </td> <td colspan="2" style="text-align: justify"> </td><td> </td><td style="font-weight: bold"> </td> <td colspan="2" style="font-weight: bold; text-align: center">March 31,</td><td style="font-weight: bold"> </td><td style="font-weight: bold"> </td> <td colspan="2" style="font-weight: bold; text-align: center">December 31,</td><td style="font-weight: bold"> </td></tr> <tr style="vertical-align: bottom"> <td style="font-weight: bold; text-align: justify; border-bottom: Black 1.5pt solid">Description</td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">Level</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">2026</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">2025</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td></tr> <tr style="vertical-align: bottom"> <td style="text-align: justify">Assets:</td><td> </td> <td colspan="2" style="text-align: justify"> </td><td> </td><td> </td> <td colspan="2" style="text-align: justify"> </td><td> </td><td> </td> <td colspan="2" style="text-align: justify"> </td><td> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 64%; text-align: justify">SEPA put rights asset (Note 10)</td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left"> </td><td style="width: 9%; text-align: center">3</td><td style="width: 1%; text-align: left"> </td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left">$</td><td style="width: 9%; text-align: right"><div style="-sec-ix-hidden: hidden-fact-65">-</div></td><td style="width: 1%; text-align: left"> </td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left">$</td><td style="width: 9%; text-align: right">155</td><td style="width: 1%; text-align: left"> </td></tr> </table>

155000

As a result, as of March 31, 2026, the fair value of SEPA put rights asset was deemed de minimis. As of December 31, 2025, the fair value of the put rights under each advance notice was estimated using the Black Scholes model, incorporating the following assumptions:<table cellpadding="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif; border-spacing: 0px;"> <tr style="vertical-align: bottom"> <td style="text-align: justify"> </td><td style="font-weight: bold"> </td> <td colspan="2" style="font-weight: bold; text-align: center">December 31,</td><td style="font-weight: bold"> </td></tr> <tr style="vertical-align: bottom"> <td style="text-align: justify"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">2025</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 88%; text-align: justify">Stock price</td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left">$</td><td style="width: 9%; text-align: right">4.23</td><td style="width: 1%; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify">Risk-free interest rate</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">3.5 to 3.7</td><td style="text-align: left">%</td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: justify">Exercise price</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">4.06</td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify">Expected term (in years)</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">0.25 to 0.92</td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: justify">Expected volatility</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"> 78-86</td><td style="text-align: left">%</td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify">Expected dividend yield</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">0</td><td style="text-align: left">%</td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: justify">Number of shares under each advance notice</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">27,100</td><td style="text-align: left"> </td></tr> </table>

4.23

3.5

3.7

4.06

0.25

0.92

27100

The changes in the fair value of Level 3 financial assets and liabilities for the three months ended March 31, 2026 are as follows: <table cellpadding="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif; border-spacing: 0px;"> <tr style="vertical-align: bottom"> <td style="padding-bottom: 1.5pt; text-align: justify"> </td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td> <td colspan="2" style="border-bottom: Black 1.5pt solid; font-weight: bold; text-align: center">SEPA Put Rights Asset</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 88%; text-align: justify">Fair value as of January 1, 2026</td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left">$</td><td style="width: 9%; text-align: right">96</td><td style="width: 1%; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="padding-bottom: 1.5pt; text-align: justify">Change in fair value</td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right">(96</td><td style="padding-bottom: 1.5pt; text-align: left">)</td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="padding-bottom: 4pt; text-align: justify">Fair value as of March 31, 2026</td><td style="padding-bottom: 4pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left">$</td><td style="border-bottom: Black 4pt double; text-align: right">0</td><td style="padding-bottom: 4pt; text-align: left"> </td></tr> </table>

96000

-96000

5. License and Collaboration Agreements NJCTTQ Collaboration Agreement In January 2019, the Company entered into a collaboration agreement with Nanjing Chia Tai Tianquing Pharmaceutical Co., Ltd. (“NJCTTQ”) to research, develop and commercialize two anti-Claudin 18.2 lead antibodies (the “NJCTTQ agreement”). Under the NJCTTQ agreement, the Company granted a non-exclusive, non-sublicensable research license and an exclusive, sublicensable license to NJCTTQ within the People’s Republic of China and Thailand (the “NJCTTQ Territory”). The initial term of this agreement was 5 years, which could be automatically renewed for another 5 years. If no collaboration project reached the clinical stage within the first 5 years of the NJCTTQ agreement, then this agreement would not have been renewed. The agreement expired in January 2024. The Company was eligible to receive up to an aggregate of $405,000 of non-refundable milestone payments from NJCTTQ upon achieving certain development, regulatory approval, and commercialization and sales milestones for each unique licensed antibody or product in NJCTTQ Territory. The Company agreed to pay NJCTTQ up to an aggregate of $5,000 in nonrefundable amounts upon achieving of a regulatory milestone in the Company’s territory, which includes all other countries other than the NJCTTQ Territory. No milestones have been reached through the expiration of this agreement in January 2024, no products were sold by NJCTTQ, and no related revenue amounts have been recorded in the accompanying condensed consolidated financial statements. The Company and NJCTTQ agreed to pay reciprocal royalties, with each of them paying the other party low single-digit royalties, tiered based on net sales per calendar year in its territory. The agreement remains unrenewed as of March 31, 2026 after the expiration of its initial term. However, notwithstanding the agreement’s expiration, the low single-digit royalties and the $5,000 regulatory milestone payable to NJCTTQ based on commercial approval in the Company’s territory, as described above, will continue to apply. Through March 31, 2026, no products were sold by NJCTTQ or the Company under the NJCTTQ agreement and no regulatory milestones were achieved by the Company in the Company’s territory. ABP-201 Collaboration and License Agreement In January 2020, the Company’s consolidated subsidiary, Abmed, entered into a collaboration and license agreement with ABI (the “ABP-201 Agreement”), pursuant to which the Company granted to ABI an exclusive, royalty-bearing, license under specified patent rights to make, use and sell certain of its proprietary ANG-2/VEGF-HIRK bispecific antibodies within the licensed territory comprising People’s Republic of China, Japan, South Korea, Southeast Asia, the Middle East and the Commonwealth of Independent States. Unless earlier terminated in accordance with its terms, the agreement remains in effect on a country-by-country basis until the expiration of the last royalty term in such country. Under the ABP-201 Agreement, ABI agreed to use commercially reasonable efforts to reach certain development and commercialization milestones for such bispecific antibodies within specified territories and timeframes. ABI is committed to pay the Company up to $56,500 in milestone payments upon achieving certain research and development events, up to $485,000 in milestone payments based on annual net sales per each licensed product, and a double-digit percentage royalty in the low teens, tiered based on cumulative net sales by ABI, its affiliates or sublicensees beginning with the first commercial sale of a licensed product in its territory. No milestones have been reached through March 31, 2026, no products were sold by ABI, and no related revenue amounts have been recorded in the accompanying condensed consolidated financial statements. Celltrion Collaboration and License Agreement In September 2022, the Company entered into an exclusive collaboration and license agreement with Celltrion (the “Original Celltrion Agreement”). The Company and Celltrion entered into an amendment to the agreement in October 2024 in connection with the execution of the Celltrion Subscription Agreement (the “Amended Celltrion Agreement”). The amendment is subject to termination by the Company or Celltrion if (i) the share purchase under the Celltrion Subscription Agreement is not completed, or (ii) the Celltrion Subscription Agreement is terminated pursuant to Section 7 of the Celltrion Subscription Agreement. Under the Amended Celltrion Agreement, the Company granted Celltrion a worldwide exclusive license under specified patent rights to develop, make, have made, import, export, use, have used, sell and have sold certain of its proprietary ABP-102 bispecific antibodies. The license agreement also provides that the Company is to perform certain preclinical in vitro studies. The license agreement will remain in effect for so long as ABP-102 is being developed or commercialized anywhere in the world. Celltrion may terminate the license agreement at any time by providing six months prior written notice to the Company.Celltrion is committed to pay the Company up to $10,000 under the Original Celltrion Agreement and $6,000 under the Amended Celltrion Agreement in milestone payments upon granting the license and achieving certain research and development events, and up to $1,750,000 in milestone payments based on annual net sales per each licensed product. The proceeds from commercialization are subject to a 50/50 profit split. Amounts that may be paid by third-party collaborators, for example upfronts, milestones and/or royalty payments from territorial commercialization partners, are also subject to a 50/50 split. Following commercial approval of ABP-102, the Company has agreed to reimburse Celltrion 87.5% under the Original Celltrion Agreement and 250% under the Amended Celltrion Agreement of its direct and certain indirect costs and expenses incurred through first commercial sale. Under the Original Celltrion Agreement, Celltrion is entitled to offset amounts otherwise due to us under the agreement until our share of these costs has been paid back; provided that the Company is entitled to a minimum 25% (or 50% under the Amended Celltrion Agreement) of profit from commercial sales and from third-party collaborators regardless of the amount of unreimbursed development costs outstanding (and then 50% once the reimbursement has been made in full). During the three months ended March 31, 2026 and 2025, the Company did not recognize any revenue under the agreement with Celltrion. The Company had $183 in accounts receivable from Celltrion related to the research and development services as of both March 31, 2026 and December 31, 2025. The accounts receivable balance of $183 was collected in April 2026. Milestone Payments. The Company is entitled to development milestones under the Original Celltrion Agreement and certain regulatory milestone payments which are paid upon receipt of regulatory approvals. Except for the first milestone of $2,000 achieved in 2022, no other milestone payments were earned through March 31, 2026. The Company evaluated whether the remaining milestones are considered probable of being reached and determined that their achievement is highly dependent on factors outside of the Company’s control. Therefore, these payments have been fully constrained and are not included in the transaction price. At the end of each subsequent reporting period, the Company will re-evaluate the probability of achievement of each milestone and any related constraint, and if necessary, adjust its estimate of the overall transaction price. Any such adjustments will be recorded on a cumulative catch-up basis, which would affect the reported amount of collaboration revenues in the period of adjustment. Profit Splits. As the license is deemed to be the predominant item to which profit splits relate, the Company will recognize revenue when the related sales or third-party collaborator income occur. No profit split revenue has been recognized from inception through March 31, 2026.

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6. Commitments under Research and Collaboration Agreements MedImmune License Agreement In August 2016, the Company entered into a collaboration and license agreement with MedImmune Limited (“MedImmune”), pursuant to which the Company received from MedImmune an exclusive, worldwide, royalty-bearing, sublicensable (subject to certain conditions) license to certain intellectual property rights relating to the Company’s ABP-200 product candidates (the “MedImmune License Agreement”). The Company agreed to use commercially reasonable efforts to reach certain development and commercialization milestones for such bispecific antibodies within specified timeframes. Unless earlier terminated in accordance with its terms, the MedImmune License Agreement, as amended, remains in effect on a country-by-country basis until the expiration of the last royalty term in such country as to be determined by the launch of products based on the ABP-200 product candidates. The Company is no longer developing ABP-200. Under the MedImmune License Agreement, the Company agreed to pay milestone and royalty payments, including up to $244,000 in milestone payments, which are comprised of $14,000 upon meeting certain clinical development milestones, $80,000 upon achieving certain regulatory events and $150,000 upon meeting certain worldwide commercial sales thresholds; and tiered high-single to low double-digit percentage royalties based on annualized net sales of each product commercialized from our collaboration on a country-by-country basis. No milestones have been reached and no products were sold by the Company through March 31, 2026.NCI License Agreement In August 2017, the Company entered into a patent license agreement with the National Cancer Institute (the “NCI”), a division of the National Institutes of Health (the “NIH”), pursuant to which the Company received an exclusive, worldwide license to make, use, sell, offer to sell and import products covered by the licensed patents in the field of using certain monoclonal antibodies as monospecific or bispecific antibodies for the treatment of liver cancer (the “NCI License Agreement”). The license agreement was amended in May 2020 and October 2023 and the field of use was narrowed to the development and commercialization of a bispecific antibody for the treatment of GPC-3 expressing liver cancer using a particular moiety for targeting GPC3 and the timeline for development and commercialization was extended. Unless earlier terminated, the Company’s agreement with NCI will expire upon expiration of all licensed patent rights. The Company may also terminate the agreement as to any licenses in any country or territory upon 60 days written notice. Pursuant to the NCI agreement and amendments, the Company agreed to pay low single-digit royalties based on net sales of licensed products as well as milestone payments of up to $3,995 due upon achievement of clinical and regulatory milestones, and up to $12,000 milestone payments due upon achievement of commercial milestones. No milestones have been reached and no products were sold by the Company through March 31, 2026. The Company also has to pay the guaranteed annual minimum royalties of $25 starting on the effective date of the agreement (which annual minimum royalties may be credited against the running royalties on net sales of any licensed products or services). During each of the three months ended March 31, 2026 and 2025, the Company incurred $6, in minimum royalty payments, which are included in research and development expenses. As of March 31, 2026 and December 31, 2025, the accrued royalties were $52 and $25, included in accounts payable on the condensed consolidated balance sheets. Under the amendment entered into in March 2020, the Company is also liable for the extension royalties of $225 payable under this agreement which were rescheduled to become due in several installments starting in March 2022. As of both March 31, 2026 and December 31, 2025, the accrued extension royalties were $200, included in accrued expenses and accounts payable in the condensed consolidated balance sheets. The Company also agreed to reimburse patent costs for all documented out of pocket costs associated with the preparation, filing, prosecution and maintenance of patent rights. During both the three months ended March 31, 2026 and 2025, the Company did not incur any expenses related to the patent costs reimbursements. Mabwell License Agreement In October 2020, the Company entered into an exclusive collaboration and license agreement with Mabwell (the “Mabwell License Agreement”). The agreement was amended in November 2020. Under the Mabwell license agreement, the Company received a non-exclusive, royalty-free research purpose license as well as an exclusive commercial license within certain territories, as defined in the agreement, to Mabwell’s series of anti-SARS-CoV-2 monoclonal antibodies. Under the agreement, the Company is responsible for conducting at its sole expense, research and preclinical, clinical and other developments of any licensed products and bears all development costs and expenses related to obtaining or maintenance of marketing authorizations of licensed products in its territories. Mabwell is obligated, at the Company’s request, to supply the Licensed Antibodies to the Company for clinical trial purpose at costs plus margin as defined in the agreement. The parties agreed to undertake certain joint clinical research and development activities with a portion of the costs contributed by Mabwell. Unless earlier terminated, the Mabwell License Agreement will expire on the occurrence of the last to expire royalty term, which is the later of a) the expiration of the last to expire valid claim of the patent rights and b) ten years from the first commercial sale of such Licensed Product, and determined on jurisdiction-by-jurisdiction basis. Either party may terminate the agreement in the event of any uncured material breach by the other party. The agreement provides for development milestones of up to $32,500 and annual sales milestone payments of up to $50,000 payable by the Company to Mabwell. The agreement also provides for a profit sharing, with Mabwell sharing 50% of the net profits from the licensed product sales in certain territories as defined in the agreement. The Company will also make tiered royalty payments in the mid to high single digits on net sales of commercial products in the licensed territory.During the three months ended March 31, 2026 and 2025, development activities under the Mabwell collaboration agreement were immaterial to the condensed consolidated financial statements. No milestones have been reached and no products were sold under the Mabwell License Agreement through March 31, 2026. MSK License Agreement In March 2017, the Company entered into an exclusive license agreement with Memorial Sloan Kettering Cancer Center (the “MSK License Agreement”), pursuant to which the Company received an exclusive, royalty-bearing, worldwide license under specified patent rights to make, use and sell certain of MSK’s proprietary Her2-huOKT3 bispecific antibodies. The agreement was amended on March 31, 2017, on March 31, 2018, and January 1, 2020. Unless earlier terminated in accordance with its terms, the agreement was to remain in effect on a country-by-country basis until the expiration of the last royalty term in such country as to be determined by the launch of products based on MSK antibodies. On September 19, 2023, MSK License Agreement was terminated by MSK due to the Company’s failure to make the payments for the patent costs reimbursements discussed below. Under the MSK License Agreement, as amended, the Company agreed to use commercially reasonable efforts to reach certain development and commercialization milestones for such bispecific antibodies within specified territories and timeframes. The Company was committed to pay MSK up to $10,500 in milestone payments upon achieving certain research and development and commercialization events or within a certain number of months of the effective date, up to $30,000 in milestone payments based on net sales, and tiered mid-single-digit percentage royalties based on annualized net sales of each product commercialized from the collaboration with guaranteed annual minimum royalties between $20 and $30 depending on certain development events. During the three months ended March 31, 2026 and 2025, the Company did not incur any minimum royalties or milestone payments under this agreement. As of both March 31, 2026 and December 31, 2025, the accrued minimum royalty and milestone payments were $790, included in accounts payable in the condensed consolidated financial statements. The Company also agreed to reimburse patent costs for all documented out of pocket costs associated with the preparation, filing, prosecution and maintenance of patent rights in the license territory. During the three months ended March 31, 2026 and 2025, the Company incurred no expenses related to the patent costs reimbursements. As of both March 31, 2026 and December 31, 2025, the liabilities for the patent costs reimbursements were $273, included in accrued expenses and accounts payable in the condensed consolidated financial statements. As of both March 31, 2026 and December 31, 2025, the accrued liabilities for the unpaid interest on the outstanding minimum royalty and milestone payments due to MSK were $169, included in accrued expenses. The company has ceased accruing further interest as a result of the termination of the MSK License Agreement. See Note 7 for discussion of the June 2023 demand letter.VAZYME License agreement In April 2021, the Company entered into a License Agreement with VAZYME Biotech Co., Ltd (“VAZYME”) (the “VAZYME License Agreement”), pursuant to which the Company was granted an exclusive, perpetual, royalty-bearing, worldwide license under specified patent rights to research, develop and commercialize VAZYME proprietary anti-SARS-CoV-2 monoclonal antibodies. Unless earlier terminated in accordance with its terms, the agreement remains in effect on a country-by-country basis until the expiration of the last royalty term in such country. Under the VAZYME License Agreement, the Company agreed to use commercially reasonable efforts to reach certain research and development, and commercialization milestones for such antibodies. The Company also agreed to pay $200 to VAZYME at the effective date of the agreement. The Company is committed to pay VAZYME up to $11,100 in milestone payments upon achieving certain research and development events, up to $70,000 in milestone payments based on annual net sales, and tiered low single-digit percentage royalties based on annualized net sales of each product commercialized from the collaboration. No milestones in the VAZYME License Agreement have been reached through March 31, 2026. In December 2021, the Company entered into a Cooperation Agreement with Chengdu Bio-Innovate Pharmaceutical Technology Co., Ltd (“Bio-Innovate”) and a three-way sharing agreement with VAZYME and Bio-Innovate (“the Company”, “VAZYME” and “Bio-Innovate”, collectively “all parties”), pursuant to which the Company entrusted Bio-Innovate to perform certain preclinical testing and all parties agreed that VAZYME will ship the agreed antibodies to Bio-Innovate rather than the Company to fulfill the requirements under the VAZYME License Agreement. For the three months ended March 31, 2026 and 2025, the Company did not incur any expenses related to the VAZYME License Agreement. As of both March 31, 2026 and December 31, 2025, the accrued liabilities under this agreement were $200, included in accounts payable in the condensed consolidated financial statements.

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7. Commitments and Contingencies Litigation and other matters The Company, from time to time, is subject to legal proceedings and claims that arise in the ordinary course of business. Resolution of any such matter could have a material adverse effect on the results of operations and financial condition. The Company considers all claims on a periodic basis and based on known facts assesses whether potential losses are considered reasonably possible, probable and estimable. Based upon this assessment, the Company then evaluates disclosure requirements and whether to accrue for such claims in its consolidated financial statements. The Company records a provision for contingent liability when it is both probable that a loss has been incurred and the amount of the loss can be reasonably estimated. On September 12, 2023, a contract research organization (“CRO”) vendor filed a lawsuit against the Company based on the Company’s failure to make certain installments pursuant to a settlement agreement entered into with this vendor on January 23, 2023. Under the settlement agreement, the Company agreed to pay a total of $1,644 to the vendor, with $600 due 5 business days after the settlement effective date and ten monthly installments, approximately $104 each, starting in February 2023. The Company made the upfront payment and the first four monthly installments for a total of $1,016 but failed to make the monthly installment payments due after May 2023. On January 24, 2024, the Company received endorsement on motion for default judgment which requested the Company to pay approximately $700 to the CRO vendor. During the three months ended March 31, 2026 and 2025, the Company accrued an additional $21 and $21 in interest, respectively, included in interest expense. As of March 31, 2026 and December 31, 2025, the outstanding balance under this settlement agreement was $890 and $869, respectively. These amounts are included in accounts payable and accrued expenses in the condensed consolidated financial statements. In addition to the lawsuit from a CRO vendor above, the Company accrued $325 as of both March 31, 2026 and December 31, 2025, related to disputed invoices with vendors. In June 2023, the Company received a notice of breach from MSK followed by a notice of termination in September 2023, pursuant to which MSK demanded payments totaling $1,230 for the services performed under the MSK License Agreement (see Note 6). The corresponding liability is included in accounts payable and accrued expenses in the condensed consolidated financial statements as of both March 31, 2026 and December 31, 2025.The MedImmune License Agreement (see Note 6) provides for a research plan with target dates for an IND application (July 2021) and Phase II commencement (December 2022). These target dates were not met, which gives MedImmune (now AstraZeneca) a termination right. The Company does not expect a material impact on its business if MedImmune/AstraZeneca terminates this agreement. This license was originally entered into in connection with the development of ABP-200, which the Company is no longer developing. The Company believes that it does not need the intellectual property licensed under that agreement for the development and eventual commercialization of ABP-201 or any of its other programs. On June 17, 2025, the Company received a complaint from a former director asserting that the Company owes the former director a total of $748 for consulting fees, bonuses, and for unpaid promissory note principal and interest. The total principal and interest on the promissory note were $137 and $135, as of March 31, 2026 and December 31, 2025, respectively (see Note 9). In November 2025, the Company made a $140 payment on this claim which was withheld by the court until the case is resolved. The remaining liability of $475 was included in accrued expenses in the condensed consolidated financial statements as of December 31, 2025. On November 10, 2025, the Suffolk Superior Court in Massachusetts issued a preliminary injunction prohibiting the transfer of the Company’s assets outside the ordinary course of business. On April 15, 2026, the Company settled this claim in full for the total amount of approximately $390 (see Note 14). The Company made $390 payment in April 2026 and received $140 funds withheld back in May 2026. As a result, the accrued expense as of March 31, 2026 was adjusted down by $362 to reflect the change in estimated liability related to this claim. On October 22, 2025, the Company received a demand for payment from Integral Molecular, Inc. in the amount of approximately $182, recorded in accounts payable in the condensed consolidated balance sheet as of March 31, 2026 and December 31, 2025. The Company is currently in negotiations to settle this claim. On October 23, 2025, the Company received a demand for payment from Brookline Capital Markets, a division of Arcadia Securities LLC, in the amount of $140, recorded in accounts payable in the condensed consolidated balance sheet as of March 31, 2026 and December 31, 2025. The Company is currently in negotiations to settle this claim. Excise Tax Liability At the Closing Date, the Company assumed the excise tax liability of $4,330, as adjusted as discussed further below, from ACAB related to the redemptions of shares in 2023 and calculated as 1% of the shares redeemed during fiscal year 2023. On August 16, 2022, the Inflation Reduction Act of 2022 (the “IR Act”) was signed into federal law. The IR Act provides for, among other things, a new U.S. federal 1% excise tax on certain repurchases of corporate stock by publicly traded U.S. domestic corporations and certain U.S. domestic subsidiaries of publicly traded foreign corporations occurring on or after January 1, 2023. The excise tax is imposed on the repurchasing corporation itself, not its shareholders from which shares are repurchased. The amount of the excise tax is generally 1% of the fair market value of the shares repurchased at the time of the repurchase. However, for purposes of calculating the excise tax, repurchasing corporations are permitted to net the fair market value of certain new stock issuances against the fair market value of stock repurchases during the same taxable year. In addition, certain exceptions apply to the excise tax. The U.S. Department of the Treasury (the “Treasury”) has been given authority to provide regulations and other guidance to carry out and prevent the abuse or avoidance of the excise tax. During the second quarter of 2024, the IRS issued regulations with respect to the timing and payment of the excise tax. Pursuant to those regulations, the Company would need to file a return and remit payment for any liability incurred during the period from January 1, 2023 to December 31, 2023 on or before October 31, 2024. The Company filed the excise tax return in October 2024 and engaged with the IRS in determining a payment plan for the balance.The Company was unable to pay its obligation in full, and, as such, it was subject to additional interest and penalties which were estimated at 8% interest per annum and a 0.5% underpayment penalty per month or portion of a month up to 25% of the total liability for any amount that was unpaid from November 1, 2024 until paid in full. In March 2025, the Company received the letter from the Internal Revenue Service of the United States Department of Treasury (the “IRS”), setting up the meeting with the Company to discuss the unsettled tax matters of ACAB and referencing $4,401 amount owed in relation to the 2023 excise taxes, of which $210 was in interest and penalties. Pending further discussions with the IRS, the Company recorded the excess of $1,268 over the Company’s estimate as the additional excise tax liability assumed from ACAB as of December 31, 2024. On November 24, 2025, the IRS published the rule providing additional clarification on the application of the excise tax to redemptions of stock (the “2025 Rule”). Among other things, the 2025 Rule provided transitional relief for stock issued before August 16, 2022 that was subject to mandatory redemption or a unilateral put option. As ACAB issued the redeemable stock prior to August 16, 2022 and this stock was subject to mandatory repurchase upon certain events outside of ACAB’s control, the Company concluded that the redemptions of ACAB redeemable stock qualified for the transitional relief. As a result, the Company derecognized the $4,401 excise tax liability in the fourth quarter of 2025, since the excise tax liability was no longer considered probable, and included the liability reversal in other income on the consolidated statement of operations at that time. Merger Earnout Former holders of the Legacy Abpro common stock and Legacy Abpro preferred stock are eligible to receive up to 483,334 additional shares of the Company’s Common Stock (“Contingent Earnout Shares”) if, within five calendar years after the closing of the Merger, the volume weighted average price of shares of the Company’s Common Stock on Nasdaq, or any other national securities exchange on which the shares of the Company’s Common Stock are then traded (“VWAP”) meets or exceeds three-tier target prices defined in the Merger agreement. No merger earnout milestones were achieved through March 31, 2026.

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8. Forward Purchase Agreement On November 7, 2024, ACAB and Legacy Abpro entered into a Confirmation of an OTC Equity Prepaid Forward Transaction (the “Forward Purchase Agreement” or “Transaction”) with YA (the “Seller”) to which a maximum of up to 16,667 common stock shares were subject to the Transaction. At the Closing Date, the Seller purchased 3,333 shares from third parties (“Recycled Shares”), pursuant to the pricing date notice dated November 12, 2024, and paid approximately $1,100 (the “Prepayment Amount”) to the redeeming shareholders. Pursuant to the terms of the Forward Purchase Agreement, at the Closing Date, the Company remitted the Prepayment Amount into an escrow account for the benefit of the Seller. On January 28, 2025, YA elected to effect an Optional Early Termination (as described in the Forward Purchase Agreement) with respect to all 3,333 shares subject to the Forward Purchase Agreement which terminated the agreement as a whole. YA paid the Company the Early Termination Obligation in the aggregate amount of $132. The Forward Purchase Agreement was accounted for at fair value as an asset in accordance with the guidance in ASC Topic 815 Derivatives and Hedging (“ASC 815”), with subsequent changes in the fair value recorded in profits and losses. The fair value of the Forward Purchase Agreement asset was $132 at the settlement date. The Company recorded the loss on the change in the fair value of $23 in other (expense) income in the condensed consolidated statement of operations for the three months ended March 31, 2025.

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9. Notes Payable Note Payable In January 2025, the Company entered into an insurance premium financing agreement and borrowed a total principal amount of $553. The note bore an annual interest rate of 7.74% and matured in September 2025. The interest expense on the note amounted to $0 for the three months ended March 31, 2025. The note was paid in full prior to September 30, 2025.Notes Payable – Related Parties Promissory Note with ABI On October 18, 2023, the Company entered into a promissory note agreement with Abpro Bio International, Inc. (“ABI”), a significant investor in the Company, to receive up to $6,000. The promissory note accrues interest at a rate of 5% per annum on the principal amount of each installment from the installment funding date until the maturity date and at a rate of 7% per annum after the maturity date if any amounts then remain outstanding. The “Maturity Date” is defined in the agreement as the earlier of (i) eighteen months from the funding date and (ii) the successful closing of the Merger. On August 22, 2024, ACAB entered into the Abpro Bio Subscription Agreement with ABI, pursuant to which ABI purchased 20,749 newly-issued shares of the Company’s common stock, concurrently with the closing of the Merger at a price of $300.00 per share, for an aggregate purchase price of $6,225, of which $4,225 was paid through the conversion of the balance due by the Company to ABI under the promissory note agreement and the remainder of $2,000 in cash. In addition, ABI received an aggregate of 41,498 incentive shares. As of March 31, 2026 and December 31, 2025, the outstanding principal balances under the promissory notes with ABI was $0. As of both March 31, 2026 and December 31, 2025, accrued interest totaling $191 is included in accrued expenses in the condensed consolidated balance sheets. No additional interest is being accrued from the Closing Date through March 31, 2026, as there is no outstanding principal. Promissory Notes with Executive and Director On December 29, 2023, Legacy Abpro issued promissory notes to one of its executives and one of its directors, in the principal amount of $176 and $124, respectively, for deferred bonuses. Amounts under the promissory notes plus accrued interest are due and payable on the earlier of (i) the closing of the Merger and (ii) June 29, 2025. These promissory notes accrue interest at 5% per annum until the maturity date and 7% thereafter. At the Closing Date, the Company paid $150 toward these promissory notes. As of both March 31, 2026 and December 31, 2025, $147 of principal was outstanding. Interest expense on these promissory notes totaled $2 for each of the three months ended March 31, 2026 and 2025, respectively, included in interest expense in the condensed consolidated statements of operations. Accrued interest on these promissory notes totaled $24 and $22 as of March 31, 2026 and December 31, 2025, respectively, included in accrued expenses in the condensed consolidated balance sheets. The $124 outstanding note and related accrued interest were settled in full through the settlement of the complaint in April 2026 (see Notes 7 and 14). On April 18, 2024, the Company entered into a separate promissory note agreement with the same executive to receive, as amended, up to $2,158 in funding. During the year ended December 31, 2024, the Company received $1,997 from the executive under this agreement. These advances accrued interest at 7.5% per annum through the maturity date and at 9.5% per annum after the maturity date if any amounts then remain outstanding. All advances, plus accrued interest, were due and payable on the earlier of (i) the closing of the Merger and (ii) November 20, 2024. At the Closing, the outstanding promissory notes of $1,997 were converted into 20,000 newly issued common stock shares. Accrued interest on these promissory notes totaled $72 as of both March 31, 2026 and December 31, 2025, included in accrued expenses in the condensed consolidated balance sheets. No additional interest is being accrued from the Closing Date through March 31, 2026, as there is no outstanding principal. On February 7, 2025, the Company issued 28,333 common stock warrants to the executive (the “Executive Warrants”). The Executive Warrants are exercisable at $99.90 per share and expire on February 7, 2035. 14,166 of the Executive Warrants were exercisable on the issuance date, 6,667 warrants became exercisable on the one-year anniversary of the issuance date, and 7,500 warrants will become exercisable on the two-year anniversary of the issuance date. The warrants were fair valued and immediately expensed at the issuance date as an additional interest expense related to the executive’s promissory note. The fair value of the Executive Warrants at the issuance date of $714 was determined using the Black-Scholes option pricing model based on the following assumptions: (a) fair value of common stock of $32.10 per share, (b) expected volatility of 90.00%, (c) dividend yield of 0%, (d) risk-free interest rate of 4.49%, and (e) expected life of 10 years. For the three months ended March 31, 2025, the Company recognized $714 additional interest expense related to the Executive Warrants. In January 2026, the Company entered into a loan agreement with its Chief Executive Officer and Board of Directors Chairman for an unsecured loan in the principal amount of $147 to fund the premium for the Company’s directors’ and officers’ liability insurance. The loan has a nine-month term from the date of advance and may be prepaid at any time without penalty. No interest accrued on the loan during the first three months following funding; thereafter, the outstanding principal bears interest at a variable rate equal to the three-month Term SOFR plus 2.0% per annum, with any accrued interest payable at maturity or upon earlier repayment. The loan was not secured by any collateral and is not guaranteed by any third party. As of March 31, 2026, the outstanding balance on this loan was $147.

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0.02

147000

10. Standby Equity Purchase Agreement Convertible Notes On October 30, 2024, Legacy Abpro and ACAB entered into a Standby Equity Purchase Agreement (the “SEPA”) with YA II PN, Ltd. (“YA”). Subject to the satisfaction of the conditions set forth in the SEPA, YA committed to advance to the Company the aggregate principal amount of up to $5,000 (the “Pre-Paid Advance”), which shall be evidenced by convertible promissory notes (each a “Convertible Note”). On November 14, 2024, the Company received the first Pre-Paid Advance and entered into a Convertible Note (defined below). The second Pre-Paid Advance was to be in a principal amount of $2,000 and advanced on the later of (i) the second trading day after the initial registration statement filed pursuant to the Registration Rights Agreement (as defined below) becomes effective and (ii) the second trading day after the required shareholder approval to issue shares of the post-combination Company’s common stock in excess of 20% of the Company’s outstanding shares pursuant to Nasdaq Rules (the “Exchange Cap”) has been obtained. At the special meeting of stockholders held on April 8, 2025, the Company obtained stockholder approval for the issuance of shares over the Exchange Cap. On November 14, 2024 (the “First Convertible Note Issuance Date”), pursuant to the SEPA, the Company entered into a Convertible Promissory Note (the “First Convertible Note”) with YA for $3,000 and received net proceeds of $2,755, net of the original issuance discount of 8% (the “Convertible Note Discount”). On June 23, 2025 (the “Second Convertible Note Issuance Date”), pursuant to the SEPA, the Company entered into a Convertible Promissory Note (the “Second Convertible Note”) and together with the First Convertible Note, the “Convertible Notes”) with YA for $2,000 and received net proceeds of $1,840, net of the Convertible Note Discount. The Convertible Notes had the maturity date of November 13, 2025 (subject to earlier repayments based on Amortization Event described below) and bore interest at a rate of 0% (or 18% upon the occurrence of an uncured Event of Default). The Convertible Notes were convertible at the option of the holder at any time after the issuance dates based on the conversion price determined as the lower of (i) $345.00 per share of Common Stock (the “Fixed Price”), or (ii) 94% of the lowest daily VWAP during the 5 consecutive trading days immediately preceding the conversion date (the “Variable Price”), but which Variable Price could not be lower than the Floor Price then in effect (the “Conversion Feature”). The Floor Price at the First Issuance Date was $34.62 per share calculated as 20% of the closing price of the Company’s stock on November 12, 2024. The Floor Price was adjusted downward to $5.70 per share on February 12, 2025 when the initial registration statement was declared effective by the SEC. On April 29, 2025, in accordance with the terms of the Convertible Promissory Note, the Company reduced the Floor Price down to $4.50 per share. The conversion was subject to the limitations including beneficial ownership limitation, principal market limitation and monthly conversion limits. If the Company, at any time while the Convertible Notes were outstanding, were to issue any shares of Common Stock (other than pursuant to the SEPA) for no consideration or for a price per share that is lower than the Fixed Price then in effect, the Fixed Price would have been reduced to equal the lowest price per share of such issuances. On April 20, 2025, the Company entered into an amendment to SEPA with YA, pursuant to which, the definition of the conversion price was amended to state that the Fixed Price should be adjusted (downwards only) to equal the VWAP of the Common Shares over the three (3) Trading Days immediately preceding the 20th Trading Day following the Issuance Date if such price is lower than the initial Fixed Price. As a result, at the amendment date, the Fixed Price was reset down to $50.40 per share. The Convertible Notes were redeemable at the option of the Company if the volume-weighted-average price (“VWAP”) of the Company’s Common Stock was less than $345.00 which may be adjusted downward upon payment of stock dividend, stock split or reclassification, or if the Company issued common stock for no consideration or at a price lower than the then-effective Fixed Price.Under the terms of the Convertible Notes, the Amortization Event was to occur if (i) the daily VWAP is less than the Floor Price for five trading days during a period of seven consecutive trading days (a “Floor Price Event”), (ii) unless the Company has obtained the approval from its stockholders for the issuance of shares pursuant to the transactions contemplated in the SEPA in excess of the Exchange Cap, the Company has issued in excess of 99% of the Common Shares available under the Exchange Cap (an “Exchange Cap Event”), or (iii) any time after the Effectiveness Deadline (as defined in the Registration Rights Agreement entered into in relation to the SEPA), YA was unable to utilize a Registration Statement to resell Underlying Shares for a period of 10 consecutive trading days (a “Registration Event”). If at any time after the Issuance Date, and from time to time thereafter, an Amortization Event was to occur, then the Company had to make monthly payments beginning on the 7th trading day after the Amortization Event Date and continuing on the same day of each successive month. Each monthly payment had to be in an amount equal to the sum of (i) $1,250 of principal in the aggregate among the Convertible Notes (or the outstanding principal if less than such amount) (the “Amortization Principal Amount”), plus (ii) the payment premium equal to 5% of the Amortization Principal Amount, and (iii) accrued and unpaid interest hereunder as of each payment date. The obligation of the Company to make monthly prepayments related to an Amortization Event was to be cease (with respect to any payment that has not yet come due) if any time after the Amortization Date (A) in the event of a Floor Price Event, on the date that was the 7th consecutive trading day that the daily VWAP was greater than the Floor Price then in effect, or the date that the Company reduces the Floor Price in accordance with the terms of this Note, (B) in the event of a Registration Event, the condition or event causing the Registration Event has been cured or the Holder was able to resell the Common Shares issuable upon conversion of this Note without limitations in accordance with Rule 144 under the Securities Act, or (C) in the event of an Exchange Cap Event, the date the Company has obtained stockholder approval to increase the number of Common Shares under the Exchange Cap and/or the Exchange Cap no longer applied, unless a subsequent Amortization Event occurs. No Amortization Events occurred from the Note Issuance Dates through the date the Convertible Notes were converted into common stock shares as discussed below. It was determined, in accordance with ASC 815, that the Conversion Feature was required to be bifurcated due to the adjustments to the settlement amount of this embedded feature that are not inputs to the fair value measurement of a fixed-for-fixed forward or option on equity shares, and should be recorded as a liability (the “Embedded Derivative Liability”) at fair value with a corresponding amount recorded as a discount on the Convertible Notes. The Embedded Derivative Liability was marked to market at each reporting period end with any changes recorded in other income or expense. The fair value of the Embedded Derivative Liability associated with the First Convertible Note was estimated at $69 at the issuance date based on the difference between the fair value of the convertible note with these embedded features and the fair value without each one of these embedded features. The fair value of the Embedded Derivative Liability associated with the Second Convertible Note was estimated at $93 at the issuance date. The total discount resulting from the Convertible Note Discount and the bifurcation of the Embedded Derivative Liability at the issuance dates was amortized over the terms of the Convertible Notes through non-cash interest expense using the effective interest method. The non-cash interest expense related to the discount amortization was $0 and $76 for the three months ended March 31, 2026 and 2025, respectively, and was included in interest expense in the condensed consolidated statements of operations. SEPA Put Rights Under the terms of the SEPA, starting at the Closing Date, the Company has the right, but not the obligation (“SEPA Put Rights”), to issue shares of its common stock to YA (“Advance Shares”, and such issuance and sale, an “Advance”) and YA shall subscribe for and purchase from the Company such Advance Shares, through written notice by the Company to YA (“Advance Notice”), provided (i) no balance is outstanding under a Convertible Note, or (ii) if there is a balance outstanding under a Convertible Note, an Amortization Event (as defined above), has occurred in accordance with and subject to the terms of the SEPA. The SEPA contemplates purchase by YA of up to $50,000 in aggregate gross purchase price for newly issued shares of the Company’s common stock. If any amount remains outstanding under a Convertible Note, without the prior written consent of YA, the Company may only (other than with respect to a deemed Advance Notice pursuant to an Investor Notice (described below)) submit an Advance Notice (A) if an Amortization Event has occurred and the obligation of the Company to make monthly prepayments under the Convertible Note has not ceased, and (B) YA pays the aggregate purchase price owed by the Company from such Advance by offsetting the amount of the Advance Proceeds against an equal amount outstanding under the subject Convertible Note. Any such sales were subject to certain limitations, including that YA could not purchase any shares that would result in it owning more than 4.99% of the Company’s common stock, or any shares that, aggregated with any related transaction, would exceed 19.9% of all shares of common stock outstanding on the date of the SEPA unless shareholder approval was obtained allowing for issuances in excess of such amount.For as long as there was an outstanding balance under a Convertible Note, YA had the right, but not the obligation, by delivery to the Company of Investor Notices (as defined in the SEPA), to cause an Advance Notice to be deemed delivered by YA, which triggers the issuance and sale of Advance Shares to YA, subject to terms and conditions as specified in the SEPA. The purchase price for the Advance Shares is the price per Advance Share obtained by multiplying the Company’s stock price (i) by 96% in respect of an Advance Notice delivered by the Company with an Option 1 Pricing Period (defined by reference to VWAP on the trading day the Advance Notice is submitted), (ii) 97% in respect of an Advance Notice with an Option 2 Pricing Period (defined by reference to the lowest daily VWAP on three consecutive trading days commencing on the Advance Notice Date), or (iii) in the case of any Advance Notice delivered pursuant to an Investor Notice, equal to the Conversion Price (as defined in the Convertible Note). The Company accounted for the SEPA Put Rights as an asset at fair value in accordance with the guidance in ASC 815, due to the adjustments to the settlement amount of this derivative instrument that are not inputs to the fair value measurement of a fixed-for-fixed forward or option on equity shares. In January and February 2026, the Company issued 3,162,785 shares of common stock with the aggregate gross purchase price of $7,264 under Advance Notices to YA in accordance with the terms of the SEPA. The Company incurred $508 of issuance costs associated with these Advances. As a result of the written notification received from the Nasdaq Panel on February 18, 2026 (see Note 1), the trading of the Company’s common stock was suspended at the open of trading on NASDAQ on February 23, 2026 and as a result, the Company is unable to comply with the registration and listing requirements to raise capital under the SEPA. As a result, as of March 31, 2026, the fair value of SEPA put rights asset was deemed de minimis. The fair value of the SEPA Put Rights was $96 as of December 31, 2025.

5000000

2000000

0.20

3000000

2755000

0.08

2000000

1840000

2025-11-13

0.18

345

0.94 P5D

34.62

0.20 5.7 4.5 P3D

50.4

345 P5D P7D 0.99 P10D

1250000

0.05

69000

93000

76000

50000000

0.0499 0.199 0.96 0.97

3162785

7264000

508000

96000

11. Stockholders’ Equity Common and Preferred Stock The Company’s Amended and Restated Certificate of Incorporation provides the Company’s board of directors with the authority to issue up to 1,000,000 shares of $0.0001 par value preferred stock in one or more series and to establish from time to time the number of shares to be included in each such series, by adopting a resolution and filing a certification of designations. Voting powers, designations, powers, preferences and relative, participating, optional, special and other rights shall be stated and expressed in such resolutions. There were zero preferred shares outstanding as of March 31, 2026 and December 31, 2025. Warrants As of March 31, 2026 and December 31, 2025, there were 500,000 outstanding public warrants (“Public Warrants”). The Public Warrants have the exercise price of $114.90 per share and became exercisable 12 months from the closing of ACAB’s Initial Public Offering, which closed on January 19, 2022, and will expire five years from the Closing Date. The Company will not be obligated to deliver any common stock pursuant to the exercise of a Public Warrant and will have no obligation to settle such Public Warrant exercise unless a registration statement under the Securities Act covering the issuance of the common stock issuable upon exercise of the Public Warrants is then effective and a prospectus relating thereto is current, subject to the Company satisfying its obligations with respect to registration. No warrant will be exercisable, and the Company will not be obligated to issue shares of common stock upon exercise of a warrant unless common stock issuable upon such warrant exercise has been registered, qualified or deemed to be exempt under the securities laws of the state of residence of the registered holder of the warrants.The Company may redeem the Public Warrants: <table cellpadding="0" style="font: 10pt Times New Roman, Times, Serif; width: 100%; border-spacing: 0px;"> <tr style="vertical-align: top"> <td style="width: 0.5in"> </td> <td style="width: 0.25in">●</td> <td>in whole and not in part;</td></tr> <tr style="vertical-align: top"> <td> </td> <td> </td> <td> </td></tr> <tr style="vertical-align: top"> <td> </td> <td>●</td> <td>at a price of $0.30 per warrant;</td></tr> <tr style="vertical-align: top"> <td> </td> <td> </td> <td> </td></tr> <tr style="vertical-align: top"> <td> </td> <td>●</td> <td style="text-align: justify">upon not less than 30 days’ prior written notice of redemption given after the warrants become exercisable to each warrant holder; and</td></tr> <tr style="vertical-align: top"> <td> </td> <td> </td> <td style="text-align: justify"> </td></tr> <tr style="vertical-align: top"> <td> </td> <td>●</td> <td style="text-align: justify">if, and only if, the reported last sale price of the Series A common stock equals or exceeds $540.00 per share (as adjusted for stock splits, stock dividends, reorganizations, recapitalizations and the like) for any 20 trading days within a 30-trading day period commencing once the warrants become exercisable and ending three trading days before the Company sends the notice of redemption to the warrant holders (the “Redemption Trigger”). In November 2024, the Redemption Trigger was adjusted to $179.70, as further described below.</td></tr> </table> If and when the warrants become redeemable by the Company, the Company may exercise its redemption right even if it is unable to register or qualify the underlying securities for sale under all applicable state securities laws. If the Company calls the Public Warrants for redemption, management will have the option to require all holders that wish to exercise the Public Warrants to do so on a “cashless basis,” as described in the warrant agreement. The exercise price and number of shares of common stock issuable upon exercise of the warrants may be adjusted in certain circumstances including in the event of a stock dividend, or recapitalization, reorganization, merger or consolidation. However, except as described below, the warrants will not be adjusted for issuance of common stock at a price below its exercise price. Additionally, in no event will the Company be required to net cash settle the warrants. As of March 2026 and December 31, 2025, there were 461,667 warrants held by ACAB (“Private Warrants”). The Private Warrants are identical to the Public Warrants, except that the Private Warrants are exercisable on a cashless basis and are non-redeemable so long as they are held by the initial purchasers or their permitted transferees. If the Private Warrants are held by someone other than the initial purchasers or their permitted transferees, the Private Warrants will be redeemable by the Company and exercisable by such holders on the same basis as the Public Warrants. On February 7, 2025, the Company issued 28,333 Executive Warrants (see Note 9). The following presents information about warrants to purchase common stock outstanding as of March 31, 2026: <table cellpadding="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif; border-spacing: 0px;"> <tr style="vertical-align: bottom"> <td style="text-align: justify"> </td><td> </td> <td colspan="2" style="text-align: center"> </td><td> </td><td style="font-weight: bold"> </td> <td colspan="2" style="font-weight: bold; text-align: center">Weighted-</td><td style="font-weight: bold"> </td><td style="font-weight: bold"> </td> <td style="font-weight: bold; text-align: center">Average</td></tr> <tr style="vertical-align: bottom"> <td style="text-align: center"> </td><td> </td> <td colspan="2" style="text-align: center"> </td><td> </td><td style="font-weight: bold"> </td> <td colspan="2" style="font-weight: bold; text-align: center">Average</td><td style="font-weight: bold"> </td><td style="font-weight: bold"> </td> <td style="font-weight: bold; text-align: center">Remaining</td></tr> <tr style="vertical-align: bottom"> <td style="text-align: center"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">Shares</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">Exercise Price</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">Contractual Life</td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 64%; text-align: justify; padding-bottom: 1.5pt">Warrants</td><td style="width: 1%; padding-bottom: 1.5pt"> </td> <td style="width: 1%; border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="width: 9%; border-bottom: Black 1.5pt solid; text-align: right">990,000</td><td style="width: 1%; padding-bottom: 1.5pt; text-align: left"> </td><td style="width: 1%; padding-bottom: 1.5pt"> </td> <td style="width: 1%; border-bottom: Black 1.5pt solid; text-align: left">$</td><td style="width: 9%; border-bottom: Black 1.5pt solid; text-align: right">114.60</td><td style="width: 1%; padding-bottom: 1.5pt; text-align: left"> </td><td style="width: 1%; padding-bottom: 1.5pt"> </td> <td style="width: 11%; text-align: center; padding-bottom: 1.5pt; padding-left: 5.4pt">3.8 years</td></tr> </table> No warrants were exercised during the three months ended March 31, 2026 or 2025.

1000000

0.0001

500000

114.9

P12M

P5Y

0.3 540 P20D P30D 179.7

461667

28333

The following presents information about warrants to purchase common stock outstanding as of March 31, 2026: <table cellpadding="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif; border-spacing: 0px;"> <tr style="vertical-align: bottom"> <td style="text-align: justify"> </td><td> </td> <td colspan="2" style="text-align: center"> </td><td> </td><td style="font-weight: bold"> </td> <td colspan="2" style="font-weight: bold; text-align: center">Weighted-</td><td style="font-weight: bold"> </td><td style="font-weight: bold"> </td> <td style="font-weight: bold; text-align: center">Average</td></tr> <tr style="vertical-align: bottom"> <td style="text-align: center"> </td><td> </td> <td colspan="2" style="text-align: center"> </td><td> </td><td style="font-weight: bold"> </td> <td colspan="2" style="font-weight: bold; text-align: center">Average</td><td style="font-weight: bold"> </td><td style="font-weight: bold"> </td> <td style="font-weight: bold; text-align: center">Remaining</td></tr> <tr style="vertical-align: bottom"> <td style="text-align: center"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">Shares</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">Exercise Price</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">Contractual Life</td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 64%; text-align: justify; padding-bottom: 1.5pt">Warrants</td><td style="width: 1%; padding-bottom: 1.5pt"> </td> <td style="width: 1%; border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="width: 9%; border-bottom: Black 1.5pt solid; text-align: right">990,000</td><td style="width: 1%; padding-bottom: 1.5pt; text-align: left"> </td><td style="width: 1%; padding-bottom: 1.5pt"> </td> <td style="width: 1%; border-bottom: Black 1.5pt solid; text-align: left">$</td><td style="width: 9%; border-bottom: Black 1.5pt solid; text-align: right">114.60</td><td style="width: 1%; padding-bottom: 1.5pt; text-align: left"> </td><td style="width: 1%; padding-bottom: 1.5pt"> </td> <td style="width: 11%; text-align: center; padding-bottom: 1.5pt; padding-left: 5.4pt">3.8 years</td></tr> </table>

990000

114.6

P3Y9M18D

12. Share-Based Compensation 2024 Equity Incentive Plan The Company’s 2024 Equity Incentive Plan (the “2024 Plan”) became effective at the Closing Date. As of March 31, 2026, 297,319 shares of common stock were available for issuance under the 2024 Plan. The initial number of shares authorized for issuance under the 2024 Plan was 208,026. The 2024 Plan provides that on January 1 of each year commencing January 1, 2026 and ending on December 31, 2034, the 2024 Plan reserve will automatically increase in an amount equal to the lesser of (a) 5% of the number of shares of the Company’s common stock outstanding on December 31 of the preceding year and (b) a number of shares of common stock determined by the Company’s board of directors. As a result, the number of shares authorized for issuance under the 2024 Plan increased by 136,663 on January 1, 2026. Under the 2024 Plan, the Company can grant non-statutory stock options, or NSOs, incentive stock options, or ISOs, stock appreciation rights, restricted stock, restricted stock units (“RSUs”), unrestricted stock, performance awards and other forms of awards to eligible employees and nonemployees.2014 Stock Incentive Plan The 2014 Stock Incentive Plan (the “2014 Plan”) of Legacy Abpro expired as of the Closing Date, in accordance with its original terms. As a result of the expiration, no further awards may be granted under the 2014 Plan. As of March 31, 2026, there were 184,141 options outstanding under the 2014 Plan. Stock options granted to employees and directors typically vest over four years. Stock options granted to non-employees typically vest immediately at the grant date. The maximum contractual term of the stock options is ten years. The Company granted restricted stock units (“RSUs”) to various employees and directors under the 2014 Plan. These RSUs cliff vested on the first anniversary of the grant date. Stock Options The summary of the Company’s stock option activity is as follows: <table cellpadding="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif; border-spacing: 0px;"> <tr style="vertical-align: bottom"> <td style="text-align: center"> </td><td style="padding-bottom: 1.5pt"> </td> <td colspan="2" style="text-align: center; border-bottom: Black 1.5pt solid">Number of Stock Options</td><td style="padding-bottom: 1.5pt"> </td><td style="padding-bottom: 1.5pt"> </td> <td colspan="2" style="text-align: center; border-bottom: Black 1.5pt solid">Weighted- Average Exercise Price</td><td style="padding-bottom: 1.5pt"> </td><td style="padding-bottom: 1.5pt"> </td> <td colspan="2" style="text-align: center; border-bottom: Black 1.5pt solid">Weighted- Average Remaining Contractual Life</td><td style="padding-bottom: 1.5pt"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 64%; text-align: justify">Outstanding at December 31, 2025</td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left"> </td><td style="width: 9%; text-align: right">217,549</td><td style="width: 1%; text-align: left"> </td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left">$</td><td style="width: 9%; text-align: right">50.24</td><td style="width: 1%; text-align: left"> </td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left"> </td><td style="width: 9%; text-align: right">4.0</td><td style="width: 1%; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify">Granted</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-73">—</div></td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-74">—</div></td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-75">—</div></td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: justify">Exercised</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-76">—</div></td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-77">—</div></td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-78">—</div></td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify">Forfeited/Expired/Cancelled</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">(25,328</td><td style="text-align: left">)</td><td> </td> <td style="text-align: left">$</td><td style="text-align: right">51.38</td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-79">—</div></td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: justify; padding-bottom: 1.5pt">Outstanding at March 31, 2026</td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right">192,221</td><td style="padding-bottom: 1.5pt; text-align: left"> </td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left">$</td><td style="border-bottom: Black 1.5pt solid; text-align: right">49.70</td><td style="padding-bottom: 1.5pt; text-align: left"> </td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right">4.2</td><td style="padding-bottom: 1.5pt; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify; padding-bottom: 2.5pt">Exercisable at March 31, 2026</td><td style="padding-bottom: 2.5pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left"> </td><td style="border-bottom: Black 4pt double; text-align: right">192,217</td><td style="padding-bottom: 2.5pt; text-align: left"> </td><td style="padding-bottom: 2.5pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left">$</td><td style="border-bottom: Black 4pt double; text-align: right">49.69</td><td style="padding-bottom: 2.5pt; text-align: left"> </td><td style="padding-bottom: 2.5pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left"> </td><td style="border-bottom: Black 4pt double; text-align: right">4.2</td><td style="padding-bottom: 2.5pt; text-align: left"> </td></tr> </table> Restricted Stock Units The summary of the Company’s restricted stock unit activity is as follows: <table cellpadding="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif; border-spacing: 0px;"> <tr style="vertical-align: bottom"> <td style="text-align: justify"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">Number of Shares</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">Weighted- Average Grant Date Fair Value</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">Weighted- Average Remaining Vesting Period</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 64%; text-align: justify">Outstanding at December 31, 2025</td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left"> </td><td style="width: 9%; text-align: right">31,169</td><td style="width: 1%; text-align: left"> </td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left">$</td><td style="width: 9%; text-align: right">7.78</td><td style="width: 1%; text-align: left"> </td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left"> </td><td style="width: 9%; text-align: right">1.4</td><td style="width: 1%; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify; padding-left: 0.125in">Granted</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-80">—</div></td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-81">—</div></td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-82">—</div></td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: justify; padding-left: 0.125in">Vested</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">(6,666</td><td style="text-align: left">)</td><td> </td> <td style="text-align: left">$</td><td style="text-align: right">8.85</td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-83">—</div></td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify; padding-bottom: 1.5pt; padding-left: 0.125in">Forfeited</td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right"><div style="-sec-ix-hidden: hidden-fact-84">—</div></td><td style="padding-bottom: 1.5pt; text-align: left"> </td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right"><div style="-sec-ix-hidden: hidden-fact-85">—</div></td><td style="padding-bottom: 1.5pt; text-align: left"> </td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right"><div style="-sec-ix-hidden: hidden-fact-86">—</div></td><td style="padding-bottom: 1.5pt; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: justify; padding-bottom: 2.5pt">Outstanding at March 31, 2026</td><td style="padding-bottom: 2.5pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left"> </td><td style="border-bottom: Black 4pt double; text-align: right">24,503</td><td style="padding-bottom: 2.5pt; text-align: left"> </td><td style="padding-bottom: 2.5pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left">$</td><td style="border-bottom: Black 4pt double; text-align: right">7.49</td><td style="padding-bottom: 2.5pt; text-align: left"> </td><td style="padding-bottom: 2.5pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left"> </td><td style="border-bottom: Black 4pt double; text-align: right">1.5</td><td style="padding-bottom: 2.5pt; text-align: left"> </td></tr> </table> As of March 31, 2026, 6,808 RSUs were vested in accordance with their terms, but the shares of common stock were not issued to the holders. On October 22, 2024, the Company’s board of directors authorized the issuance of 20,449 RSUs to the Company’s employees and a Board member, however no awards were issued until the fourth quarter of 2025. The Company expensed the fair value of the authorized RSU on a straight-line basis over their vesting period. In December 2025, the Company issued the RSUs to these employees with different terms. The issuance of the RSUs was accounted for as a modification with $396 RSU liability accrued through the issuance date reclassified into additional paid-in capital. As the fair value of the awards issued was less than the fair value of the promised awards, the Company continued to recognize share-based compensation based on the grant date fair value in accordance with ASC 718-20-35-3(b), which states that total recognized compensation cost for an equity award shall at least equal the fair value of the award at the grant date. For the three months ended March 31, 2026 and 2025, the Company recorded $245 and $204, respectively, in share-based compensation expense related to these authorized awards.Share-Based Compensation Expense The summary of the recorded share-based compensation expense is as follows: <table cellpadding="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif; border-spacing: 0px;"> <tr style="vertical-align: bottom"> <td style="text-align: justify"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="6" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">Three months ended March 31,</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td></tr> <tr style="vertical-align: bottom"> <td style="text-align: justify"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">2026</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">2025</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td></tr> <tr style="vertical-align: bottom"> <td style="text-align: justify"> </td><td> </td> <td colspan="2" style="text-align: justify"> </td><td> </td><td> </td> <td colspan="2" style="text-align: justify"> </td><td> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 76%; text-align: justify">Research and development</td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left">$</td><td style="width: 9%; text-align: right"><div style="-sec-ix-hidden: hidden-fact-87">-</div></td><td style="width: 1%; text-align: left"> </td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left">$</td><td style="width: 9%; text-align: right">10</td><td style="width: 1%; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify; padding-bottom: 1.5pt">General and administrative</td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right">302</td><td style="padding-bottom: 1.5pt; text-align: left"> </td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right">502</td><td style="padding-bottom: 1.5pt; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: justify; padding-bottom: 2.5pt; padding-left: 0.125in">Total stock-based compensation</td><td style="padding-bottom: 2.5pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left">$</td><td style="border-bottom: Black 4pt double; text-align: right">302</td><td style="padding-bottom: 2.5pt; text-align: left"> </td><td style="padding-bottom: 2.5pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left">$</td><td style="border-bottom: Black 4pt double; text-align: right">512</td><td style="padding-bottom: 2.5pt; text-align: left"> </td></tr> </table> As of March 31, 2026, there was no unrecognized compensation cost related to stock option awards. As of March 31, 2026, there was approximately $2,091 of unrecognized compensation cost related to unvested restricted stock awards that are expected to be recognized over a weighted-average period of 1.4 years.

297319

208026

0.05

136663

184141

P4Y

P10Y

The summary of the Company’s stock option activity is as follows: <table cellpadding="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif; border-spacing: 0px;"> <tr style="vertical-align: bottom"> <td style="text-align: center"> </td><td style="padding-bottom: 1.5pt"> </td> <td colspan="2" style="text-align: center; border-bottom: Black 1.5pt solid">Number of Stock Options</td><td style="padding-bottom: 1.5pt"> </td><td style="padding-bottom: 1.5pt"> </td> <td colspan="2" style="text-align: center; border-bottom: Black 1.5pt solid">Weighted- Average Exercise Price</td><td style="padding-bottom: 1.5pt"> </td><td style="padding-bottom: 1.5pt"> </td> <td colspan="2" style="text-align: center; border-bottom: Black 1.5pt solid">Weighted- Average Remaining Contractual Life</td><td style="padding-bottom: 1.5pt"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 64%; text-align: justify">Outstanding at December 31, 2025</td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left"> </td><td style="width: 9%; text-align: right">217,549</td><td style="width: 1%; text-align: left"> </td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left">$</td><td style="width: 9%; text-align: right">50.24</td><td style="width: 1%; text-align: left"> </td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left"> </td><td style="width: 9%; text-align: right">4.0</td><td style="width: 1%; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify">Granted</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-73">—</div></td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-74">—</div></td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-75">—</div></td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: justify">Exercised</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-76">—</div></td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-77">—</div></td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-78">—</div></td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify">Forfeited/Expired/Cancelled</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">(25,328</td><td style="text-align: left">)</td><td> </td> <td style="text-align: left">$</td><td style="text-align: right">51.38</td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-79">—</div></td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: justify; padding-bottom: 1.5pt">Outstanding at March 31, 2026</td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right">192,221</td><td style="padding-bottom: 1.5pt; text-align: left"> </td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left">$</td><td style="border-bottom: Black 1.5pt solid; text-align: right">49.70</td><td style="padding-bottom: 1.5pt; text-align: left"> </td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right">4.2</td><td style="padding-bottom: 1.5pt; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify; padding-bottom: 2.5pt">Exercisable at March 31, 2026</td><td style="padding-bottom: 2.5pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left"> </td><td style="border-bottom: Black 4pt double; text-align: right">192,217</td><td style="padding-bottom: 2.5pt; text-align: left"> </td><td style="padding-bottom: 2.5pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left">$</td><td style="border-bottom: Black 4pt double; text-align: right">49.69</td><td style="padding-bottom: 2.5pt; text-align: left"> </td><td style="padding-bottom: 2.5pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left"> </td><td style="border-bottom: Black 4pt double; text-align: right">4.2</td><td style="padding-bottom: 2.5pt; text-align: left"> </td></tr> </table>

217549

50.24

P4Y

25328

51.38

192221

49.7

P4Y2M12D

192217

49.69

P4Y2M12D

The summary of the Company’s restricted stock unit activity is as follows: <table cellpadding="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif; border-spacing: 0px;"> <tr style="vertical-align: bottom"> <td style="text-align: justify"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">Number of Shares</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">Weighted- Average Grant Date Fair Value</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">Weighted- Average Remaining Vesting Period</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 64%; text-align: justify">Outstanding at December 31, 2025</td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left"> </td><td style="width: 9%; text-align: right">31,169</td><td style="width: 1%; text-align: left"> </td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left">$</td><td style="width: 9%; text-align: right">7.78</td><td style="width: 1%; text-align: left"> </td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left"> </td><td style="width: 9%; text-align: right">1.4</td><td style="width: 1%; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify; padding-left: 0.125in">Granted</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-80">—</div></td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-81">—</div></td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-82">—</div></td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: justify; padding-left: 0.125in">Vested</td><td> </td> <td style="text-align: left"> </td><td style="text-align: right">(6,666</td><td style="text-align: left">)</td><td> </td> <td style="text-align: left">$</td><td style="text-align: right">8.85</td><td style="text-align: left"> </td><td> </td> <td style="text-align: left"> </td><td style="text-align: right"><div style="-sec-ix-hidden: hidden-fact-83">—</div></td><td style="text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify; padding-bottom: 1.5pt; padding-left: 0.125in">Forfeited</td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right"><div style="-sec-ix-hidden: hidden-fact-84">—</div></td><td style="padding-bottom: 1.5pt; text-align: left"> </td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right"><div style="-sec-ix-hidden: hidden-fact-85">—</div></td><td style="padding-bottom: 1.5pt; text-align: left"> </td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right"><div style="-sec-ix-hidden: hidden-fact-86">—</div></td><td style="padding-bottom: 1.5pt; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: justify; padding-bottom: 2.5pt">Outstanding at March 31, 2026</td><td style="padding-bottom: 2.5pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left"> </td><td style="border-bottom: Black 4pt double; text-align: right">24,503</td><td style="padding-bottom: 2.5pt; text-align: left"> </td><td style="padding-bottom: 2.5pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left">$</td><td style="border-bottom: Black 4pt double; text-align: right">7.49</td><td style="padding-bottom: 2.5pt; text-align: left"> </td><td style="padding-bottom: 2.5pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left"> </td><td style="border-bottom: Black 4pt double; text-align: right">1.5</td><td style="padding-bottom: 2.5pt; text-align: left"> </td></tr> </table>

31169

7.78

P1Y4M24D

6666

8.85

24503

7.49

P1Y6M

6808

20449

396000

245000

204000

The summary of the recorded share-based compensation expense is as follows: <table cellpadding="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif; border-spacing: 0px;"> <tr style="vertical-align: bottom"> <td style="text-align: justify"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="6" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">Three months ended March 31,</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td></tr> <tr style="vertical-align: bottom"> <td style="text-align: justify"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">2026</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td><td style="font-weight: bold; padding-bottom: 1.5pt"> </td> <td colspan="2" style="font-weight: bold; text-align: center; border-bottom: Black 1.5pt solid">2025</td><td style="padding-bottom: 1.5pt; font-weight: bold"> </td></tr> <tr style="vertical-align: bottom"> <td style="text-align: justify"> </td><td> </td> <td colspan="2" style="text-align: justify"> </td><td> </td><td> </td> <td colspan="2" style="text-align: justify"> </td><td> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 76%; text-align: justify">Research and development</td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left">$</td><td style="width: 9%; text-align: right"><div style="-sec-ix-hidden: hidden-fact-87">-</div></td><td style="width: 1%; text-align: left"> </td><td style="width: 1%"> </td> <td style="width: 1%; text-align: left">$</td><td style="width: 9%; text-align: right">10</td><td style="width: 1%; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: White"> <td style="text-align: justify; padding-bottom: 1.5pt">General and administrative</td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right">302</td><td style="padding-bottom: 1.5pt; text-align: left"> </td><td style="padding-bottom: 1.5pt"> </td> <td style="border-bottom: Black 1.5pt solid; text-align: left"> </td><td style="border-bottom: Black 1.5pt solid; text-align: right">502</td><td style="padding-bottom: 1.5pt; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="text-align: justify; padding-bottom: 2.5pt; padding-left: 0.125in">Total stock-based compensation</td><td style="padding-bottom: 2.5pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left">$</td><td style="border-bottom: Black 4pt double; text-align: right">302</td><td style="padding-bottom: 2.5pt; text-align: left"> </td><td style="padding-bottom: 2.5pt"> </td> <td style="border-bottom: Black 4pt double; text-align: left">$</td><td style="border-bottom: Black 4pt double; text-align: right">512</td><td style="padding-bottom: 2.5pt; text-align: left"> </td></tr> </table>

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13. Related Parties The Company has certain promissory notes outstanding with executives and directors as of March 31, 2026 and December 31, 2025. See Note 9. On January 15, 2020, Legacy Abpro entered into an agreement for various consulting services, as defined in the agreement, with a former director of Legacy Abpro. On January 1, 2023, the Company entered into a new consulting agreement with the same director, which superseded the agreement dated in January 2020. The agreement was terminated during the year ended December 31, 2024. In the fourth quarter of 2025, the Company made a $140 payment on this claim. As of both March 31, 2026 and December 31, 2025, the unpaid amounts were $47. The outstanding balance under this agreement was fully settled in April 2026. See Note 7 for the details of the complaint from the former director. On December 1, 2021, Legacy Abpro entered into a consulting agreement with a member of the Company’s Board of Directors. Under the agreement, Legacy Abpro is obligated to pay fees for various consulting services, as defined in the agreement. This agreement was terminated in May 2022. The Company did not incur any expenses under this agreement during the years ended December 31, 2025 and 2024. As of March 31, 2026 and December 31, 2025, the unpaid amounts were $0 and $8, respectively. On March 13, 2023, the Company’s Former CEO, upon the approval of the Company’s Board of Directors, transferred $5,000 from the Company’s bank account at First Republic Bank to his personal bank account as an emergency response to the collapse of First Republic Bank. This amount was recorded as a receivable from related party as of March 31, 2023. The full amount of $5,000 plus accrued interest of $18 was returned to the Company on May 3, 2023, and the remaining balance of accrued interest was $3 as of March 31, 2026 and December 31, 2025. On July 20, 2025, the Company entered into a consulting agreement with the Company’s CEO (the “CEO Consulting Agreement”). In connection with the CEO Consulting Agreement, the Company issued 16,667 RSUs, which vest in three equal installments on March 3, 2026, March 3, 2027, and March 3, 2028 and provides for an annual compensation of $300,000. The term of the CEO Consulting Agreement commenced on March 3, 2025, the date the Company’s board of directors appointed the CEO, and shall remain in full force and effect until terminated by mutual written agreement between the Company and the CEO, or by sixty days’ prior written notice by either party. Under the terms of the CEO Consulting Agreement, the Company is obligated to make the payment equal to three times the fair market value of the CEO’s equity interests in the Company, if within 12 months of a change of control event (as defined in the CEO Consulting Agreement), the CEO is involuntarily terminated without cause or resigns for good reason. The unpaid amounts owed under the CEO Consulting agreement were $0 and $175 as of March 31, 2026 and December 31, 2025, respectively.

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14. Subsequent Events On June 17, 2025, the Company received a complaint from a former director asserting that the Company owes the former director a total of $748 for consulting fees, bonuses, and for unpaid promissory note principal and interest (see Notes 7 and 9). On April 15, 2026, the Company settled this claim for the full release of obligations under the promissory note of $137 and liabilities for consulting fees and bonuses of $475 of $612 for the total amount of approximately $390, paid on April 28, 2026. On April 29, 2026, the Company settled the outstanding payable balance of $719 for $500 with Nelson Mullins pursuant to the settlement agreement executed on April 28, 2026.

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