Results of Operations and Financial Condition. On August 18, 2026, 374Water Inc. (the “ Company ”) issued an additional press release (the “ Press Release ”) reporting its full financial results for the quarter ended June 30, 2026, and certain other business information and updates. A copy of the Press Release is furnished as Exhibit 99.1 to this Current Report on Form 8-K (this “ Current Report ”) and incorporated by reference herein. The information furnished in

CFO — Charles Weiser: The Company appointed Charles Weiser as Chief Financial Officer.

of this Current Report, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “ Exchange Act ”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any filing made by the Company under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such a filing.

President and Chief Executive Officer — Daniel Bogar: Daniel Bogar was appointed as President and Chief Executive Officer with a new employment agreement.

Director — Richard H. Davis: Richard H. Davis was appointed to the Board of Directors, bringing extensive experience in investment banking and equity finance.

of this Current Report, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “ Exchange Act ”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any filing made by the Company under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such a filing.

of this Current Report on Form 8-K (this “ Current Report ”), including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “ Exchange Act ”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any filing made by the Company under the Securities Act of 1933, as amended (the “ Securities Act ”), or the Exchange Act, except as shall be expressly set forth by speci…

Chief Financial Officer — Russell Kline: Mr. Kline's employment as the Company’s Chief Financial Officer was terminated as part of a company restructuring.

Director on Nominating and Corporate Governance Committee and Compensation Committee — Stephen McKnight: Mr. McKnight was appointed to additional Board committees.

President and Chief Executive Officer — Danny Bogar: Danny Bogar was appointed as the President and Chief Executive Officer, replacing Stephen Jones.

Notice of Delisting or Failure to Satisfy a Continued Listing Rule or Standard; Transfer of Listing. On February 4, 2026, Mr. James Vanderhider, a member of the Board, notified the Board of his decision to resign from the Board effective immediately. Mr. Vanderhider’s resignation was not due to any disagreement with the Company on any matter relating to the Company’s operations, policies or practices. Following Mr. Vanderhider’s departure, a vacancy was created on the Audit Committee of the B…

Director — Stephen McKnight: The appointment of Stephen McKnight as a new Director to fill the vacancy created by Mr. Vanderhider’s resignation.

Entry into a Material Definitive Agreement. On February 7, 2026, 374Water Inc. (the “ Company ”) entered into Amendment No. 1 (“ Amendment No. 1 ”) to the Letter Agreement dated December 14, 2025 (the “ Original Agreement ” and, as amended by Amendment No. 1, the “ Agreement ”) with Mr. Yaacov (Kobe) Nagar. Pursuant to the Original Agreement, the Company agreed, among other things, to identify three candidates (the “ Candidates ”) to be appointed to the Board of Directors of the Company (the…

Director — Stephen J. Jones: Mr. Stephen J. Jones resigned from the Board to focus more on his role as Interim Chief Executive Officer and President of the Company.

Director — Buddie Joe Penn: Mr. Penn resigned from the Board, and Mr. Freels was appointed as a successor.

Director — Charles Weiser: The appointment of Charles Weiser to the Board and audit committee brings significant financial expertise and experience.

Entry into a Material Definitive Agreement. On December 14, 2025, 374Water Inc. (the “ Company ”), entered into a letter agreement (the “ Agreement ”) with Mr. Yaacov (Kobe) Nagar. Pursuant to the Agreement, Ms. Deanna Rene Estes will tender her resignation as a member of the Board of Directors of the Company (the “ Board ”), which resignation shall be effective following and no later than the date that the inspector of elections for the 2025 Special Meeting of Stockholders of the Company hel…

Material Modification to Rights of Security Holders. To the extent required by

The excerpt is incomplete and does not provide specific details about any management change.

of this Current Report on Form 8-K (this “ Current Report ”), including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “ Exchange Act ”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any filing made by the Company under the Securities Act of 1933, as amended (the “ Securities Act ”), or the Exchange Act, except as shall be expressly set forth by speci…

General Counsel — Peter Mandel: Mr. Mandel stepped down from his position as General Counsel and entered into a Separation Agreement with the Company.

President and Chief Executive Officer — Christian Gannon: Christian Gannon stepped down as President and CEO, with Stephen Jones appointed as Interim President and CEO.

of this Current Report on Form 8-K (this “ Current Report ”), including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “ Exchange Act ”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any filing made by the Company under the Securities Act of 1933, as amended (the “ Securities Act ”), or the Exchange Act, except as shall be expressly set forth by speci…

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers. As previously reported, on January 15, 2025, 374Water Inc. (the “ Company ”) received a deficiency letter (the “ Notice ”) from the Nasdaq Listing Qualifications Department (the “ Staff ”) of the Nasdaq Stock Market LLC (“ Nasdaq ”) notifying the Company that because the closing bid price for the Company’s common stock listed on Nasdaq was below $1…

Director — Stephen Jones: Appointment of Stephen Jones to the Board's Nominating and Corporate Governance Committee and Compensation Committee.