Cardio Diagnostics Holdings, Inc.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

(Mark One)

☒** ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT**

OF 1934

For the fiscal year ended December 31, 2025

☐** TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934**

**For the transition period from to **

Commission File No.001-41097

(Exact name of registrant as specified in its charter)

311 West Superior Street, Suite 444

Chicago, IL 60654

(Address of principal executive offices and Zip Code)

(855)226-9991

(Registrant’s telephone number, including area code)

Securities registered pursuant to Section 12(b) of the Exchange Act

Securities registered pursuant to Section 12(g) of the Securities Exchange Act: NONE

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes☐ No ☒

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15 (d) of the Securities Exchange Act. Yes☐ No ☒

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer,” "accelerated filer,” "smaller reporting company,” and "emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report.☐

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements.☐

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to § 240.10D-1(b).☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yes☐No ☒

As of June 30, 2025, the aggregate market value of shares held by non-affiliates of the registrant (based upon the closing sale prices of such shares on the Nasdaq Capital Market on June 30, 2025) was approximately $5.8 million. For purposes of calculating the aggregate market value of shares held by non-affiliates, we have assumed that all outstanding shares are held by non-affiliates, except for shares held by each of our executive officers, directors, and 5% or greater stockholders. In the case of 5% or greater stockholders, we have not deemed such stockholders to be affiliates unless there are facts and circumstances which would indicate that such stockholders exercise any control over our company, or unless they hold 10% or more of our outstanding common stock. These assumptions should not be deemed to constitute an admission that all executive officers, directors, and 5% or greater stockholders are, in fact, affiliates of our company, or that there are not other persons who may be deemed to be affiliates of our company.

As of March 13, 2026, there were 2,959,469 shares of common stock, par value $0.00001 issued and outstanding. Documents Incorporated by Reference: None.

TABLE OF CONTENTS

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INTRODUCTORY NOTE

Unless the context dictates otherwise, references in this Annual Report on Form 10-K to the “Company,” “Cardio,” “we,” “us,” “our,” and similar words are references to Cardio Diagnostics Holdings, Inc., a Delaware corporation, and its consolidated subsidiary. “Legacy Cardio” refers to Cardio Diagnostics, Inc. prior to the October 2022 Business Combination, which became our wholly-owned subsidiary as a result of that transaction.

Trade names and trademarks of Cardio referred to herein, and their respective logos, are our property. This Annual Report on Form 10-K may contain additional trade names and/or trademarks of other companies, which are the property of their respective owners. We do not intend our use or display of other companies’ trade names and/or trademarks, if any, to imply an endorsement or sponsorship of us by such companies, or any relationship with any of these companies.

The Company effected a 1-for-30 reverse stock split effective May 12, 2025 (the "Reverse Stock Split”). Unless otherwise indicated, all issued and outstanding stock and per share amounts referred to in this Annual Report on Form 10-K have been adjusted to reflect the Reverse Stock Split for all prior periods presented. Proportionate adjustments for the Reverse Stock Split were made to the exercise prices and number of shares issuable under the Company’s equity incentive plans and outstanding warrants, and the number of shares underlying outstanding equity awards and warrants, as applicable. See Note 1 for information and disclosures relating to adjustments related to the Reverse Stock Split.

CAUTIONARY NOTE REGARDING FORWARD LOOKING STATEMENTS

This Annual Report on Form 10-K contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, or the "Securities Act,” and Section 21E of the Securities Exchange Act of 1934, or the Exchange Act. The statements contained in this report that are not purely historical are forward-looking statements. Our forward-looking statements include, but are not limited to, statements regarding our or our management’s expectations, hopes, beliefs, intentions or strategies regarding the future. In addition, any statements that refer to projections, forecasts or other characterizations of future events or circumstances, including any underlying assumptions, are forward-looking statements. The words “anticipates,” "believe,” “continue,” “could,” “estimate,” “expect,” “intends,” “may,” “might,” “plan,” “possible,” “potential,” “predicts,” “project,” “should,” “would” and similar expressions may identify forward- looking statements, but the absence of these words does not mean that a statement is not forward-looking. Forward-looking statements in this Form 10-K may include, for example, statements such as the following:

The forward-looking statements contained in this Annual Report on Form 10-K are based on our current expectations and beliefs concerning future developments and their potential effects on us. There can be no assurance that future developments affecting us will be those that we have anticipated. These forward-looking statements involve a number of risks, uncertainties (some of which are beyond our control) or other assumptions that may cause actual results or performance to be materially different from those expressed or implied by these forward-looking statements. Should one or more of these risks or uncertainties materialize, or should any of our assumptions prove incorrect, actual results may vary in material respects from those projected in these forward-looking statements. We undertake no obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as may be required under applicable securities laws.

Recent Developments

At the Market Sales Agreement

On January 26, 2024, the Company entered into the Sales Agreement with Craig-Hallum Capital Group, LLC (“Craig-Hallum”). Pursuant to the Sales Agreement, the Company may sell, at its option, shares of its Common Stock through Craig-Hallum, as sales agent. Sales of the Common Stock were made pursuant to the Sales Agreement initially up to an aggregate of $17 million under the Company’s Registration Statement on Form S-3 filed on January 26, 2024 (File No. 333-276725), and declared effective by the SEC on February 1, 2024 (the “Initial Registration Statement”). Additional sales have been, and may continue to be made, pursuant to the Sales Agreement up to an aggregate of $9,476,508 under the Company’s Registration Statement on Form S-3 filed on February 7, 2025 (File No. 333-284775), declared effective by the SEC on February 14, 2025 (the “Additional Registration Statement”) and its accompanying Prospectus Supplement dated February 14, 2025. Subject to the terms and conditions of the Sales Agreement, Craig-Hallum may sell the shares, if any, only by methods deemed to be an “at the market” offering as defined in Rule 415 promulgated under the Securities Act. The Company has agreed to pay Craig-Hallum a sales commission of 2.5% of the gross proceeds for sales under the Sales Agreement and to provide Craig-Hallum with customary indemnification and contribution rights, including for liabilities under the Securities Act. In addition, the Company is required to reimburse Craig-Hallum for certain specified expenses in connection with entering into the Sales Agreement.

In connection with the Sales Agreement, the Company sold 825,268 common shares (24,758,057 prior to the Reverse Stock Split) at various amounts per share to investors for gross proceeds totaling $11,546,949, before deducting sales commissions of $288,921 to placement agent, during the year ended December 31, 2024. The Company also paid the placement agent a fee of $55,000.

During the year ended December 31, 2025, in connection with the Sales Agreement the Company sold 292,495 shares on the post-reverse stock split basis (which includes 206,713 shares that were sold prior to the Reverse Stock Split, originally 6,201,377 shares) of Common Stock at various amounts per share to investors for gross proceeds totaling $3,900,492 before deducting sales commissions of $96,994 to the placement agent. Subsequent to December 31, 2025, the Company sold 1,133,418 shares of Common Stock for gross proceeds totaling$3,788,174 under the At-the-Market Issuance Sales Agreement as of the date of this report.

Our business is subject to numerous risks and uncertainties, including those highlighted in the section titled “Risk Factors,” which represent challenges that we face in connection with the successful implementation of our strategy and growth of our business. The occurrence of one or more of the events or circumstances described in the section titled “Risk Factors,” alone or in combination with other events or circumstances, may have an adverse effect on our business, cash flows, financial condition and results of operations. Such risks include, but are not limited to:

Risks Related to Our Business, Industry and Business Operations

Risks Related to Our Intellectual Property

Risks Related to Government Regulation

Risks Related to Our Common Stock