Onconetix, Inc.

false 0001782107 0001782107 2026-07-28 2026-07-28 iso4217:USD xbrli:shares iso4217:USD xbrli:shares UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 28, 2026 Onconetix, Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 001-41294 83-2262816 (State or other Jurisdiction of Incorporation) (Commission File Number) (I.R.S. Employer Identification No.) 201 E. Fifth Street , Suite 1900 , Cincinnati , Ohio 45202 (Address of Principal Executive Offices) (Zip Code) Date of Report (Date of earliest event reported): ( 513 ) 620-4101 (Former name or former address, if changed since last report.) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions: ☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act: Title of Each Class Trading Symbol(s) Name of Each Exchange on Which Registered Common Stock, par value $0.00001 per share ONCO The Nasdaq Stock Market LLC Indicate by check mark whether the registrant is an emerging growth company as defined in in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☒ 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. ☐ Item 1.01 Entry into a Material Definitive Agreement PIPE Financing On July 28, 2026, Onconetix, Inc., a Delaware corporation (the “ Company ”), entered into a securities purchase agreement (the “ Securities Purchase Agreement ”) with an accredited investor (the “ PIPE Investor ”), pursuant to which the Company agreed to issue and sell to the PIPE Investor an aggregate of 37,812 shares of Series F convertible preferred stock, par value $0.00001 per share (“ Series F Preferred Stock ”), for an aggregate purchase price of $30,249,600 (the “ PIPE Financing ”). Concurrently with entering into the Securities Purchase Agreement, the Company also entered into a Registration Rights Agreement (as defined below) with the PIPE Investor, pursuant to which the Company agreed to provide the PIPE Investor with certain registration rights relating to the shares of Common Stock issuable upon conversion of the Series F Preferred Stock, as described below. The following descriptions of the Securities Purchase Agreement, the Certificate of Designations of Preferences, Rights and Limitations of the Series F Preferred Stock (the “ Certificate of Designations ”) and the Registration Rights Agreement are summaries only, do not purport to be complete and are qualified in their entirety by reference to the full text of each of those agreements, copies of which are filed as Exhibits 10.1, 3.1 and 10.2, respectively, to this Current Report on Form 8-K, and are incorporated herein by reference. Capitalized terms used but not otherwise defined herein have the meanings assigned to them in the Securities Purchase Agreement, the Certificate of Designations or the Registration Rights Agreement, as applicable. Series F Preferred Stock Certificate of Designations General . Pursuant to the Certificate of Designations, the Company has authorized the issuance of up to 42,000 shares of Series F Preferred Stock, each having a stated value of $1,000 per share (the “ Stated Value ”). The Company has issued 37,812 shares of Series F Preferred Stock to the PIPE Investor. Ranking. The Series F Preferred Stock ranks junior to any Senior Preferred Stock, pari passu with the Company’s Series C Preferred Stock, Series D Preferred Stock and Series E Preferred Stock, and senior to the Company’s Common Stock and other junior securities with respect to dividend rights and rights upon liquidation, dissolution and winding up of the Company. Dividends. Holders of the Series F Preferred Stock are entitled to receive dividends when and as declared by the Company’s board of directors out of funds legally available therefor. In addition, from and after the occurrence, and during the continuance, of any Triggering Event, Default Dividends accrue on the Stated Value of each share of Series F Preferred Stock at a rate of 15.0% per annum until such Triggering Event is cured and are payable by inclusion in the applicable Conversion Amount or upon redemption, as provided in the Certificate of Designations. Conversion Rights . Each holder may convert all or any portion of its Series F Preferred Stock into shares of the Company’s Common Stock at an initial conversion price of $0.9767 per share, subject to adjustment as provided in the Certificate of Designations. Alternate Conversion Rights. Following the Stockholder Approval Date, holders may also elect to effect alternate conversions, including following the occurrence of certain Triggering Events, at alternative conversion prices determined pursuant to the Certificate of Designations, in each case subject to the applicable Floor Price and other limitations set forth therein. Triggering Events . The Certificate of Designations contains customary Triggering Events, including, among other things, the Company’s failure to timely file or maintain the effectiveness of required registration statements, failures relating to share delivery or maintenance of an adequate share reserve, specified payment defaults, certain bankruptcy and insolvency events, suspension of trading of the Common Stock on an Eligible Market, material breaches of the transaction documents, specified change of control events and other customary events. Upon the occurrence of certain Triggering Events, holders are entitled to exercise the alternate conversion rights described above. 1 Conversion Price Adjustments . The Conversion Price is subject to customary anti-dilution adjustments for stock splits, stock dividends, stock combinations, recapitalizations and similar transactions. The Certificate of Designations also provides for adjustments in connection with certain stock combination events, issuances of Variable Price Securities and dilutive issuances, as well as voluntary reductions of the Conversion Price with the consent of the Required Holders, in each case as more particularly described in the Certificate of Designations. Change of Control; Fundamental Transactions . Upon a Change of Control, holders may require the Company to exchange their Series F Preferred Stock for the applicable Change of Control Election Price in the manner provided in the Certificate of Designations. The Certificate of Designations also restricts the Company from consummating specified Fundamental Transactions unless the successor entity (i) assumes the Company’s obligations under the Certificate of Designations and the other Transaction Documents and holders receive the rights and protections set forth therein, and (ii) is a publicly traded corporation whose shares of common stock are quoted on or listed for trading on an Eligible Market. Redemption Rights . The Company has the right, subject to the terms and conditions of the Certificate of Designations, to redeem all or a portion of the outstanding Series F Preferred Stock for cash at a redemption price equal to 125% of the greater of (i) the applicable Conversion Amount and (ii) the value determined by reference to the Conver