374Water (SCWO) investor relations material

Executive summary

• Entered into a binding agreement with a major shareholder to secure support for a 1-for-10 reverse stock split proposal at the December 15, 2025 Special Meeting.

• In exchange for voting support, agreed to significant changes in board composition, including the resignation of three directors and appointment of mutually acceptable new candidates.

• The agreement includes a voting commitment and irrevocable proxy for all shares held by the shareholder, representing about 19% of outstanding votes.

• The agreement will remain effective until either all new board candidates are appointed or 30 days after notice of breach, subject to cure provisions.

Voting matters and shareholder proposals

• The primary proposal is a reverse stock split at a 1-for-10 ratio, to be voted on at the December 15, 2025 Special Meeting.

• The shareholder has committed to vote all his shares in favor of the reverse stock split and in accordance with board recommendations on all proposals.

• Stockholders are encouraged to review the definitive proxy statement and related materials for full details on the proposals.

Board of directors and corporate governance

• Deanna Rene Estes will resign from the board following certification of the reverse stock split vote.

• Three new board candidates, mutually acceptable to both parties, will be identified and appointed, including at least one audit committee financial expert.

• Directors Buddie Joe (BJ) Penn and James Vanderhider will resign contingent on the identification of suitable replacements.

• Vacancies from resignations will only be filled by mutually agreed candidates.