TMC the metals Co Inc.

10b5-1 Trading Arrangements

During the three months ended March 31, 2026, none of our directors or officers (as defined in Section 16 of the Securities Exchange Act of 1934, as amended)adopted, modified orterminated any contract, instruction or written plan for the purchase or sale of our securities that was intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) or any “non-Rule 10b5-1 trading arrangement,” as defined in Item 408(a) of Regulation S-K.

Issuance of Common Shares to Allseas

On May 11, 2026, the Company entered into the Contract for Development Work and Commercial Production (the “Agreement”) with Allseas Deepsea Marine Contractors, a subsidiary of Allseas Group S.A. (“Allseas”).

Pursuant to the Agreement, the Company will issue to Allseas Group S.A. 7,377,835 common shares (the “Shares”) in settlement of the March 31, 2026 amount owing of $32.1 million for development work previously performed by Allseas Group S.A. and its affiliates in connection with the nodule collection system and an additional $2.3 million of initial costs as negotiated. A final share settlement of additional costs up to the date of this agreement is to be completed in accordance with the terms of the Agreement. The final Share Settlement Amount and corresponding number of Shares are subject to determination in accordance with the terms of the Agreement and have not been finally determined as of the date of this Quarterly Report. As prescribed in the Agreement, the settlement in shares is calculated using a VWAP over the 20 days preceding the effective date as stipulated in the Agreement, less a discount of 10%. Pursuant to the Agreement, Incurred Costs up to the signing of this agreement, not yet invoiced by Allseas, will be payable in any event, which the Company expects to settle in cash through production revenues, in accordance with the terms of the Agreement.

The Shares will be issued in reliance on the exemption from registration provided by Section 4(a)(2) of the Securities Act of 1933, as amended, as a transaction not involving a public offering. Allseas Group S.A. is a sophisticated investor and the Company’s largest strategic shareholder. The Shares have not been registered under the Securities Act and may not be offered or sold in the United States absent registration or an applicable exemption from registration requirements.