TMC the metals (TMC) 10-K 25 Mar 24 2023 FY Annual report Financial data

Document And Entity Information

Document And Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2023	Mar. 22, 2024	Jun. 30, 2023
Document And Entity Information
Document Type	10-K
Document Annual Report	true
Document Transition Report	false
Document Period End Date	Dec. 31, 2023
Entity File Number	001-39281
Entity Registrant Name	TMC THE METALS COMPANY INC.
Entity Incorporation, State or Country Code	A1
Entity Tax Identification Number	00-0000000
Entity Address, Address Line One	595 Howe Street, 10th Floor
Entity Address, City or Town	Vancouver,
Entity Address, State or Province	BC
Entity Address, Postal Zip Code	V6C 2T5
City Area Code	574
Local Phone Number	252-9333
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction [Flag]	true
Document Financial Statement Restatement Recovery Analysis [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 274,979,313
Entity Common Stock, Shares Outstanding		318,249,878
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Entity Central Index Key	0001798562
Amendment Flag	false
Auditor Name	Ernst & Young LLP
Auditor Firm ID	1263
Auditor Location	Vancouver, Canada
Common Shares, without par value
Document And Entity Information
Title of 12(b) Security	Common Shares, without par value
Trading Symbol	TMC
Security Exchange Name	NASDAQ
Redeemable warrants, each whole warrant exercisable for one Common Share, each at an exercise price of $11.50 per share
Document And Entity Information
Title of 12(b) Security	Redeemable warrants, each whole warrant exercisable for one Common Share, each at an exercise price of $11.50 per share
Trading Symbol	TMCWW
Security Exchange Name	NASDAQ

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Sep. 30, 2023	Jul. 31, 2023	Jun. 30, 2023	Mar. 31, 2023	Mar. 21, 2023	Dec. 31, 2022	Dec. 31, 2021
Current
Cash	$ 6,842	$ 22,548		$ 20,006	$ 28,390		$ 46,876
Receivables and prepayments	1,978	5,325		1,637	3,230		2,726
Total current assets	8,820	27,873		21,643	31,620		49,602
Non-current
Exploration contracts	43,150	43,150		43,150	43,150		43,150
Equipment	2,776	2,078		1,970	1,997		2,025
Right-of-use asset	5,721	6,198	$ 6,515
Investment	8,429	8,525		8,644	8,781	$ 9,000
Total non-current assets	60,076	59,951		53,764	53,928		45,175
TOTAL ASSETS	68,896	87,824		75,407	85,548		94,777
Current
Accounts payable and accrued liabilities	31,334	19,344		18,113	17,544		41,614
Total current liabilities	31,334	19,344		18,113	17,544		41,614
Non-current
Deferred tax liability	10,675	10,675		10,675	10,675		10,675
Royalty liability	14,000	14,000		14,000	14,000
Warrants liability	1,969	2,197		2,314	1,528		983
TOTAL LIABILITIES	57,978	46,216		45,102	43,747		53,272
EQUITY
Common shares (unlimited shares, no par value - issued: 306,558,710 (December 31, 2022 - 266,812,131))	438,239	434,099		345,775	345,090		332,882
Additional paid in capital	122,797	124,168		188,722	186,796		184,960
Accumulated other comprehensive loss	(1,216)	(1,216)		(1,216)	(1,216)		(1,216)
Deficit	(548,902)	(515,443)		(502,976)	(488,869)		(475,121)
TOTAL EQUITY	10,918	41,608		30,305	41,801		41,505	$ 92,751
TOTAL LIABILITIES AND EQUITY	$ 68,896	$ 87,824		$ 75,407	$ 85,548		$ 94,777

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parentheticals) - $ / shares	12 Months Ended
	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022
Consolidated Balance Sheets
Ordinary shares, authorized	Unlimited
Common shares, par value	$ 0	$ 0	$ 0	$ 0	$ 0
Common shares, issued	306,558,710				266,812,131

Consolidated Statements of Loss

Consolidated Statements of Loss and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2023	Jun. 30, 2023	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
Operating expenses
Exploration and evaluation expenses	$ 7,169	$ 15,267	$ 23,172	$ 49,849	$ 144,599
General and administrative expenses	6,214	11,345	15,958	22,540	29,518
Operating loss	13,383	26,612	39,130	72,389	174,117
Other items
Equity-accounted investment loss				571
Change in fair value of warrants liability	545	1,331	1,214	986	(2,143)
Foreign exchange loss	29	52	66	310	24
Interest income	(454)	(773)	(1,092)	(1,297)	(1,111)
Fees and interest on credit facility	27	277	529	781
Loss and comprehensive loss for the year, before tax	13,748	27,855	40,322	73,740	170,887
Tax expense				41	77
Loss and comprehensive loss for the year, after tax	$ 13,748	$ 27,855	$ 40,322	$ 73,781	$ 170,964
Loss per share - basic	$ 0.05	$ 0.10	$ 0.14	$ 0.26	$ 0.71
Loss per share - diluted	$ 0.05	$ 0.10	$ 0.14	$ 0.26	$ 0.71
Weighted average number of common shares outstanding - basic	272,029,603	276,702,050	282,745,892	288,643,700	239,867,019
Weighted average number of common shares outstanding - diluted	272,029,603	276,702,050	282,745,892	288,643,700	239,867,019

Consolidated Statements of Chan

Consolidated Statements of Changes in Equity - USD ($) $ in Thousands	Common stock	Additional Paid in Capital	Accumulated Other Comprehensive Loss	Deficit	Total
Balance at Dec. 31, 2021	$ 296,051	$ 102,073	$ (1,216)	$ (304,157)	$ 92,751
Balance (in Shares) at Dec. 31, 2021	225,432,493
Vesting of Allseas Warrant		69,900			69,900
Conversion of restricted share units, net of shares withheld for taxes (Note 15)	$ 6,875	(6,945)			(70)
Conversion of restricted share units, net of shares withheld for taxes (Note 15) (in shares)	2,877,068
Shares purchased under Employee Share Purchase Plan (Note 15)	$ 193	(79)			114
Shares purchased under Employee Share Purchase Plan (Note 15) (in shares)	117,929
Exercise of stock options (Note 15)	$ 142	(66)			76
Exercise of stock options (Note 15) (in shares)	118,461
Issuance of shares under PIPE financing - net of expenses (Note 12)	$ 29,621				29,621
Issuance of shares under PIPE financing - net of expenses (Note 12) (in shares)	38,266,180
Share-based compensation (Note 15)		20,077			20,077
Net Income (Loss)				(170,964)	(170,964)
Balance at Dec. 31, 2022	$ 332,882	184,960	(1,216)	(475,121)	41,505
Balance (in Shares) at Dec. 31, 2022	266,812,131
Net Income (Loss)					(13,748)
Balance at Mar. 31, 2023					41,801
Balance at Dec. 31, 2022	$ 332,882	184,960	(1,216)	(475,121)	41,505
Balance (in Shares) at Dec. 31, 2022	266,812,131
Net Income (Loss)					(27,855)
Balance at Jun. 30, 2023					30,305
Balance at Dec. 31, 2022	$ 332,882	184,960	(1,216)	(475,121)	41,505
Balance (in Shares) at Dec. 31, 2022	266,812,131
Net Income (Loss)					(40,322)
Balance at Sep. 30, 2023					41,608
Balance at Dec. 31, 2022	$ 332,882	184,960	(1,216)	(475,121)	41,505
Balance (in Shares) at Dec. 31, 2022	266,812,131
Shares issued to Allseas (Note 8)	$ 15,910				15,910
Shares issued to Allseas (Note 8) (in shares)	15,000,000
Exercise of warrant by Allseas (Note 8 and 13)	$ 70,016	(69,900)			116
Exercise of warrant by Allseas (Note 8 and 13) (in shares)	11,578,620
Issuance of shares and warrants under Registered Direct Offering, net of expenses (Note 12)	$ 11,420	3,179			14,599
Issuance of shares and warrants under Issuance of shares and warrants under Registered Direct Offering, net of expenses (Note 12) (in shares)	7,961,540
Conversion of restricted share units, net of shares withheld for taxes (Note 15)	$ 7,720	(7,690)			30
Conversion of restricted share units, net of shares withheld for taxes (Note 15) (in shares)	4,912,747
Shares purchased under Employee Share Purchase Plan (Note 15)	$ 147	(45)			102
Shares purchased under Employee Share Purchase Plan (Note 15) (in shares)	173,672
Exercise of stock options (Note 15)	$ 144	(67)			77
Exercise of stock options (Note 15) (in shares)	120,000
Expenses settled with share-based payments (Note 15)		12,360			12,360
Net Income (Loss)				(73,781)	(73,781)
Balance at Dec. 31, 2023	$ 438,239	$ 122,797	$ (1,216)	$ (548,902)	$ 10,918
Balance (in Shares) at Dec. 31, 2023	306,558,710

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2023	Jun. 30, 2023	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
Operating activities
Net Income (Loss)	$ (13,748)	$ (27,855)	$ (40,322)	$ (73,781)	$ (170,964)
Items not affecting cash:
Amortization	88	175	262	360	418
Lease expense			318	795
Share-based compensation and Expenses settled with equity	1,775	4,307	6,839	12,360	20,077
Equity-accounted investment loss				571
Change in fair value of warrants liability	545	1,331	1,214	986	(2,143)
Vesting of Allseas Warrant					69,900
Unrealized foreign exchange movement	(20)	(17)	(24)	(51)	(53)
Changes in working capital:
Receivables and prepayments	(469)	1,123	(2,364)	748	960
Accounts payable and accrued liabilities	(11,877)	(11,277)	(10,757)	(1,561)	15,202
Net cash used in operating activities	(23,472)	(31,857)	(44,359)	(59,573)	(66,603)
Investing activities
Acquisition of equipment		(75)	(175)	(578)	(1,169)
Net cash used in investing activities		(75)	(175)	(578)	(1,169)
Financing activities
Proceeds from Registered Direct Offering			15,723	15,923
Expenses paid for Registered Direct Offering			(779)	(1,182)
Proceeds from PIPE financing					30,399
Expenses paid for PIPE financing					(797)
Proceeds from employee share purchase plan		49	49	102	114
Proceeds from exercise of stock options			77	77	76
Proceeds from exercise of warrants by Allseas			116	116
Proceeds from issuance of shares		30	30	30
Proceeds from Low Carbon Royalties investment	5,000	5,000	5,000	5,000
Taxes withheld and paid on share-based compensation					(70)
Net cash provided by financing activities	5,000	5,079	20,216	20,066	29,722
Decrease in cash	(18,472)	(26,853)	(24,318)	(40,085)	(38,050)
Impact of exchange rate changes on cash	20	17	24	51	53
Cash - beginning of year	$ 46,876	$ 46,876	$ 46,876	46,876	84,873
Cash - end of year				$ 6,842	$ 46,876

Nature of Operations

Nature of Operations	12 Months Ended
	Dec. 31, 2023
Nature of Operations
Nature of Operations	1. Nature of Operations TMC the metals company Inc. (“TMC” or the “Company”) was incorporated as a Cayman Islands exempted company limited by shares on December 18, 2019 and continued as a corporation under the laws of the province of British Columbia, Canada on September 9, 2021. On September 9, 2021, the Company completed its business combination (the “Business Combination”) with DeepGreen Metals Inc. (“DeepGreen”). The Company’s corporate office, registered address and records office is located at 10th floor, 595 Howe Street, Vancouver, British Columbia, Canada, V6C 2T5. The Company’s common shares and warrants to purchase common shares are listed for trading on the Nasdaq Global Select Market (“Nasdaq”) under tickers “TMC” and “TMCWW”, respectively. The Company is a deep-sea minerals exploration company focused on the collection and processing of polymetallic nodules found on the seafloor in international waters of the Clarion Clipperton Zone in the Pacific Ocean (“CCZ”), located approximately 1,300 nautical miles southwest of San Diego, California. These nodules contain high grades of four metals (nickel, copper, cobalt, manganese) which can be used as (i) feedstock for battery cathode precursors (nickel, cobalt and manganese sulfates, or intermediate nickel-copper-cobalt matte) for electric vehicles (“EV”) and renewable energy storage markets, (ii) copper cathode for EV wiring, energy transmission and other applications and (iii) manganese silicate for manganese alloy production required for steel production. Exploration and exploitation of seabed minerals in international waters is regulated by the International Seabed Authority (“ISA”), an intergovernmental organization established pursuant to the 1994 Agreement Relating to the Implementation of the United Nations Convention on the Law of the Sea. The ISA grants contracts to sovereign states or to private contractors who are sponsored by a sovereign state. The Company’s wholly owned subsidiary, Nauru Ocean Resources Inc. (“NORI”), was granted an exploration contract (the “NORI Exploration Contract”) by the ISA in July 2011 under the sponsorship of the Republic of Nauru (“Nauru”) giving NORI exclusive rights to explore for polymetallic nodules in an area covering 74,830 square kilometers The realization of the Company’s assets and attainment of profitable operations is dependent upon many factors including, among other things: financing being arranged by the Company to continue operations, development of a nodule collection system for the recovery of polymetallic nodules from the seafloor as well as development of processing technology for the treatment of polymetallic nodules at commercial scale, the establishment of mineable reserves, the commercial and technical feasibility of seafloor polymetallic nodule collection and processing, metal prices, and regulatory approvals and environmental permitting for commercial operations. The outcome of these matters cannot presently be determined because they are contingent on future events and may not be fully under the Company’s control.

Basis of Presentation

Basis of Presentation	12 Months Ended
	Dec. 31, 2023
Basis of Presentation
Basis of Presentation	2. Basis of Presentation Statement of Compliance These consolidated financial statements have been prepared in accordance with Generally Accepted Accounting Principles in the United States (“U.S. GAAP”) and include the accounts of TMC and its wholly-owned subsidiaries. Comparative figures reported in the Consolidated Balance Sheet, for cash, receivables and prepayments, and figures reported in the Consolidated Statements of Cash Flows, for Expenses settled with equity and changes in working capital have been reclassified to conform to the current year’s presentation. Basis of Measurement These consolidated financial statements have been prepared under the historical cost convention, except for warrants liability that has been measured at fair value and are presented in United States (“US”) dollars. Consolidation These consolidated financial statements include the financial statements of the Company and its subsidiaries. The principal subsidiaries of the Company, their activities, and their geographic locations as at December 31, 2023 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Proportion of ​ ​ ​ ​ ​ ​ Interest Held Subsidiary ​ Principal Activity ​ Location ​ by the Company DeepGreen Engineering Pte. Ltd. Mineral exploration Singapore 100% DeepGreen Metals ULC Mineral exploration Canada 100% DeepGreen Resources, LLC Holding Company USA 100% DeepGreen TOML Holding 1 Ltd. Holding Company British Virgin Islands 100% DeepGreen TOML Holding 2 Ltd. Holding Company British Virgin Islands 100% DeepGreen TOML Singapore Pte. Ltd. Mineral exploration Singapore 100% Koloa Moana Resources Ltd. Holding Company Canada 100% Nauru Education and Training Foundation Inc. (“NEAT”) Holding Company Republic of Nauru 100% Nauru Health and Environment Foundation Inc. (“NHEF”) Holding Company Republic of Nauru 100% Nauru Ocean Resources Inc. Mineral exploration Republic of Nauru 100% Offshore Minerals Pty. Ltd. Mineral exploration Australia 100% The Metals Company Australia Pty Ltd Holding Company Australia 100% TMC The Metals Company UK Limited Holding Company United Kingdom 100% Tonga Offshore Mining Ltd. Mineral exploration Kingdom of Tonga 100% ​ All intra-group balances have been eliminated on consolidation.

Significant Accounting Policies

Significant Accounting Policies	12 Months Ended
	Dec. 31, 2023
Significant Accounting Policies Adopted During the Period
Significant Accounting Policies	3. Significant Accounting Policies i. Foreign Currencies The functional currency is the currency of the primary economic environment in which the entity operates. The functional currency of the Company and all its subsidiaries is the U.S. Dollar, except for NEAT and NHEF, whose functional currency is the Australian Dollar. At the end of each reporting period, monetary assets and liabilities that are denominated in foreign currencies are translated into the functional currency at the rates prevailing at that date. Non-monetary assets and liabilities carried at fair value that are denominated in currencies other than the U.S. Dollar are translated at rates prevailing at the date when the fair value was determined. All gains and losses on translation of these foreign currency transactions are included in the statements of loss and comprehensive loss. Non-monetary items that are measured at historical cost in a foreign currency are not retranslated. For consolidation purposes, the assets and liabilities of entities with functional currencies other than the US Dollar are translated at the period end rates of exchange, and the results of their operations are translated at average rates of exchange for the period. The resulting changes are recognized in accumulated other comprehensive loss within equity as currency translation differences. ii. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts in the consolidated financial statements and the notes thereto. Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, the evaluation of going concern, the valuation of share-based payments, including valuation of incentive stock options (Note 15), as well as the valuation of warrants liability (Note 13), and the valuation of the investment in Low Carbon Royalties Inc. (“Low Carbon Royalties”) (Note 9). Actual results could differ materially from those estimates. iii. Loss Per Share Basic loss per share is computed by dividing loss available to common shareholders by the weighted average number of common shares outstanding during the year. The computation of diluted loss per share assumes the conversion, exercise or contingent issuance of securities only when such conversion, exercise or issuance would have a dilutive effect on the loss per share. The dilutive effect of convertible securities is reflected in the diluted loss per share by application of the “if converted” method. The dilutive effect of outstanding options and their equivalents is reflected in the diluted loss per share by application of the treasury stock method. iv. Financial Instruments Financial assets and liabilities are recognized when the Company becomes a party to the contractual provisions of the instrument. Financial assets are derecognized when the rights to receive cash flows from the assets have expired, or have been transferred, and the Company has transferred substantially all risks and rewards of ownership. A financial liability is derecognized when the obligation specified in the contract is discharged, cancelled, or expires. The Company’s financial instruments consists of cash and cash equivalents, receivables, accounts payable and accrued liabilities, and deferred acquisition costs which are recorded at amortized cost as well as warrants to acquire common shares of the Company which are measured at fair value. v. Fair Value of Financial Instruments Fair value estimates of financial instruments are made at a specific point in time, based on relevant information about financial markets and specific financial instruments. As these estimates are subjective in nature, involving uncertainties and matters of significant judgment, they cannot be determined with precision. Changes in assumptions can significantly affect estimated fair value. The Company measures fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the reporting date. In accordance with U.S. GAAP, the Company utilizes a three-tier hierarchy, which prioritizes the inputs used in the valuation methodologies in measuring fair value: ● Level 1  - Valuations based on quoted prices in active markets for identical assets or liabilities that an entity has the ability to access. ● Level 2  - Valuations based on quoted prices for similar assets or liabilities, quoted prices for identical assets or liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable data for substantially the full term of the assets or liabilities. ● Level 3  - Valuations based on inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. In some circumstances, the inputs used to measure fair value might be categorized within different levels of the fair value hierarchy. In those instances, the fair value measurement is categorized in its entirety in the fair value hierarchy based on the lowest level input that is significant to the fair value measurement. There were no transfers between fair value measurement levels during the years ended December 31, 2023 and 2022. As at December 31, 2023 and 2022, the carrying values of cash, receivables, accounts payable and accrued liabilities approximate their fair values due to the short-term nature of these instruments. The financial instruments also include warrants which are valued at fair value as disclosed in Note 13. vi. Cash and Cash Equivalents Cash include cash on hand and term deposits with a remaining term to maturity at acquisition of three months or less. As at December 31, 2023 and 2022, the Company had no cash equivalents. vii. Equipment Equipment are stated at cost less accumulated depreciation and accumulated impairment losses. Cost includes expenditures that are directly attributable to the acquisition of the asset. Subsequent costs are included in the asset’s carrying amount or recognized as a separate asset, as appropriate, when it is probable that future economic benefits from such assets will flow to the Company and the cost of such assets can be measured reliably. The carrying amount of an asset is derecognized when it is replaced or taken out of service. Repairs and maintenance costs are charged to the statement of loss and comprehensive loss during the period they are incurred. The major categories of equipment are amortized on a declining balance basis as follows: ​ ​ ​ ​ ​ Exploration and other equipment 30 % Office equipment 30 % ​ The Company allocates the amount initially recognized to each asset’s significant components and depreciates each component separately. Amortization methods and useful life of the assets are reviewed at each financial period end and adjusted on a prospective basis, if required. Gains and losses on disposals of equipment are determined by comparing the proceeds with the carrying amount of the asset and are included in the statement of loss and comprehensive loss. viii. Exploration Contracts The Company is in the exploration stage with respect to its investment in exploration contracts and follows the practice of capitalizing costs related to the acquisition of such exploration contracts. The cost of exploration contracts will be charged to operations using a unit-of-production method based on proven and probable reserves once commercial production commences in the future. ix. Exploration and Evaluation Expenses While in the exploration phase, the Company expenses all costs related to exploration and development of exploration contracts. Such exploration and development costs include, but are not limited to, exploration contract management, geological, geochemical and geophysical studies, environmental studies and process development. x. Share-Based Compensation Share-based compensation is measured at the grant date based on the fair value of the award and is recognized over the requisite service period. Share-based compensation costs are charged to exploration and evaluation expenses or general and administrative expenses in the statement of loss and comprehensive loss. The Company recognizes forfeiture of any awards as they occur. The Company records share-based compensation from the issuance of stock options and restricted share units (“RSUs”) to employees with service-based conditions using the accelerated attribution method. For stock options and restricted share units issued with performance conditions (Note 15), the Company recognizes share-based compensation cost when the specific performance targets become probable of being achieved using the accelerated attribution method. When these costs relate to equity financing, they are netted against share capital as a share issuance cost. The fair value of stock option awards with only service and/or performance conditions is estimated on the grant date using a Black-Scholes option-pricing model. For stock options issued with market conditions (Note 15), the Company recognizes share-based compensation cost over the expected achievement period for the related market capitalization milestone determined on the grant date. If the related market capitalization milestone is achieved earlier than its expected achievement period, then any unamortized share-based compensation cost for that milestone is recognized at that time. The fair value of market-based stock option awards is estimated on the grant date using Monte-Carlo simulations. The Company at times grants common shares, stock options or RSUs in lieu of cash to certain vendors for their services to the Company. The Company recognizes the associated cost in the same period and manner as if the Company paid cash for the services provided. xi. Warrants Liability The Company evaluates all of its financial instruments, including issued share purchase warrants, to determine if such instruments are derivatives or contain features that qualify as embedded derivatives, pursuant to U.S. GAAP Accounting Standard Coding (“ASC”) 480, Distinguishing Liability from Equity (“ASC 480”), and ASC 815, Derivatives and Hedging (“ASC 815”). The classification of derivative instruments, including whether such instruments should be recorded as liabilities or as equity, is re-assessed at the end of each reporting period. The Company accounts for the Public Warrants and Private Warrants (as defined below) in accordance with the guidance contained in ASC 815 (Subtopic 40), Derivative and Hedging – Contracts in Entity’s Own Equity (“ASC 815-40”), and the U.S. Securities and Exchange Commission (“SEC”) Division of Corporation Finance’s April 12, 2021 Public Statement, Staff Statement on Accounting and Reporting Considerations for Warrants Issued by Special Purpose Acquisition Companies (“SEC Statement”), under which the 15,000,000 common share warrants issued by SOAC as part of the units offered in its initial public offering (“Public Warrants”) were determined to meet the criteria for equity classification, while the 9,500,000 private placement common share warrants issued by SOAC in a private placement simultaneously with the closing of the initial public offering (“Private Warrants”) did not meet the criteria for equity classification and were recorded as liabilities. Specifically, the terms of the Private Warrants provide for potential changes to the settlement amounts dependent upon the characteristics of the warrant holder, and, because the holder of a Private Warrant is not an input into the pricing of a fixed-for-fixed option on equity shares, such provision would preclude the Private Warrants from being classified in equity and should be classified as a liability. Accordingly, the Company classified the Private Warrants as liabilities measured at fair value and adjusts the Private Warrants to their fair value at the end of each reporting period. Fair value changes in the Private Warrants are recognized in the Company’s statement of loss and comprehensive loss. The Company granted warrants to Allseas on March 4, 2021 to acquire 11.6 million TMC common shares at a nominal value (the “Allseas Warrant”). The Allseas Warrant vested and became exercisable upon successful completion of the PMTS in the fourth quarter of 2022, and had been accounted for as equity, since the warrants do not meet the criteria to be classified as liability as defined in ASC Topic 480, Distinguishing Liabilities from Equity. The Company issued Class A Warrants under the Registered Direct Offering (Note 12) in the third quarter of 2023. The Class A Warrants issued met the criteria for equity classification and were recorded under additional paid in capital (Note 13). xii. Income Taxes Income tax expense represents the sum of current tax expense and deferred tax expense. Current tax expense is based on taxable profit for the year and includes any adjustments to tax payable in respect of previous years. Taxable profit differs from accounting profit or loss as reported in the consolidated income statement because it excludes (i) items of income or expense that are taxable or deductible in other years and (ii) items that are never taxable or deductible. The Company’s liability for current tax is calculated using tax rates that have been enacted by the balance sheet date. The Company’s policy is to account for income tax related interest and penalties in income tax expense in the accompanying statements of loss and comprehensive loss. Deferred tax income taxes are accounted for using the asset and liability method. Deferred income tax assets and liabilities are based on temporary differences, which are differences between the accounting basis and tax basis of assets and liabilities, non-capital loss, capital loss, and tax credits carryforwards and are measured using the enacted tax rates and laws expected to apply when these differences reverse. Deferred tax benefits, including non-capital loss, capital loss, and tax credit carryforwards are recognized to the extent that realization of such benefits is considered more likely than not. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in the consolidated income statement in the period that enactment occurs. When realization of deferred income tax assets does not meet the more likely than not criterion for recognition, a valuation allowance is provided. Significant Accounting Policies Adopted during the year i. Leases The Company records leases in accordance with ASC 842, Leases Lease liabilities are recognized on the commencement date of the lease based on the present value of the future lease payments over the lease term. The discount rate used to calculate the present value of lease payments is the rate implicit in the lease. Lease liabilities due within the subsequent 12 months of the reporting date are classified as current lease liabilities and are included in accounts payable and accrued liabilities on the Company’s condensed consolidated balance sheet. Lease liabilities payable after the subsequent 12 months of the reporting date are classified as non-current lease liabilities and are presented as non-current lease liability in the condensed consolidated balance sheet. ROU assets are valued at the initial measurement of the lease liability, plus any indirect costs or rent prepayments, and reduced by any lease incentives and any deferred lease payments. ROU assets are recorded as Right-of-use assets, net of any amortization on the condensed consolidated balance sheet. Operating ROU assets are amortized on a straight-line basis over the lease term, whereas Finance ROU assets are amortized on a front-loaded basis. Depending on the nature of the ROU asset, the amortization expense is either included in exploration and evaluation expenses or in general and administrative expenses. The Company subsequently measures the ROU assets for an operating lease at the amount of the remeasured lease liability (i.e. the present value of the remaining lease payments), adjusted for the remaining balance of any lease incentives received, any cumulative prepaid or accrued rent if the lease payments are uneven throughout the lease term and any unamortized initial direct costs. The ROU assets for a finance lease are subsequently measured by amortizing them on a straight-line basis over the shorter of the lease term or useful life and also adjustment for any impairments. In the third quarter of 2023, the Company entered into an Exclusive Vessel Use Agreement with Allseas (Note 8) which was recognized as a lease agreement in accordance with accounting standards. ii. Investments The Company consolidates investments over which it has control in accordance with ASC 810, Consolidation Investments-Equity Method and Joint Ventures The Company and its wholly-owned subsidiary, NORI, entered into an investment with Low Carbon Royalties on February 21, 2023 (Note 9).

Significant Accounting Estimate

Significant Accounting Estimates and Judgements	12 Months Ended
	Dec. 31, 2023
Significant Accounting Estimates and Judgements
Significant Accounting Estimates and Judgements	4. Significant Accounting Estimates and Judgements The preparation of financial statements in accordance with U.S. GAAP requires management to make judgments, estimates and assumptions that affect the application of policies and reported amounts of assets and liabilities, income and expenses. The estimates and associated assumptions are based on historical experience and various other factors that are believed to be reasonable under the circumstances, the results of which form the basis of making the judgments about carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates. Significant management judgments and estimates were applied to the following areas: i. Evaluation of Going Concern The Company evaluates its ability to operate as a going concern at each reporting period. This evaluation requires the Company to estimate its cash flow commitments over a forecast period of twelve months and whether it has the financial ability to pay for such commitments. Changes in these estimates and assumptions may have a material impact on this assessment. ii. Valuation of Share-Based Payments The fair market value of share-based awards granted to employees, non-employees and directors is based on the closing market price of the Company’s shares, on the date these were granted (Note 15). This valuation approach involves the use of estimates, judgments and assumptions that are subjective, such as those regarding the probability of future events. Changes in these estimates and assumptions impact the Company’s valuation as of the valuation date and may have a material impact on the valuation of the Company’s common shares. Changes in these assumptions used to determine the fair value of incentive stock options, including the vesting timeline of granted stock options, could have a material impact on the Company’s loss and comprehensive loss. iii. Valuation of Warrants Liability The Company re-measures the fair value of the Private Warrants at the end of each reporting period (Note 13). The fair value of the Private Warrants was estimated using a Black-Scholes option pricing model whereby the expected volatility was estimated using a binomial model based on consideration of the implied volatility from the Company’s Public Warrants adjusted to account for the call feature of the Public Warrants at prices above $18.00 during 20 trading days within any 30-trading-day period. During the year the Company issued Class A warrants as a part of the Registered Direct Offering (Note 12 & Note 13). The warrants were valued using a Monte Carlo simulation by running 250,000 trials. The model assumed that the Company’s share price follows geometric Brownian motion which is a standard assumption used in Monte Carlo univariate pricing models. The valuation was calculated under a risk-neutral framework using a zero-coupon risk-free interest rate derived from the Treasury Constant Maturities yield curve for a term until the expiry of the Warrants. The Company’s share price was simulated up to the expiration date using a blended volatility, calculated by assigning equal weights to both implied volatility of the Company’s Public Warrants and the historical volatility of the Company’s share price. iv. Valuation of Royalty Liability The Company re-measures the fair value of its royalty liability at each reporting date. As NORI is in an advanced exploration stage and pre-production, the fair value of the royalty liability is measured by using a market approach which entails examining recent royalty transactions prior to the reporting date, focusing on those transactions that involve similar metals as contained in NORI’s polymetallic nodules. The Company compares the specific characteristics of these transactions to estimate the fair value of its royalty liability at the reporting date.

Recent Accounting Pronouncement

Recent Accounting Pronouncements Issued and Adopted	12 Months Ended
	Dec. 31, 2023
Recent Accounting Pronouncements Issued and Adopted
Recent Accounting Pronouncements Issued and Adopted	5. Recent Accounting Pronouncements Issued and Adopted There were no recent accounting pronouncements applicable to the Company during the year.

Receivables and Prepayments

Receivables and Prepayments	12 Months Ended
	Dec. 31, 2023
Receivables And Prepayments.
Receivables and Prepayments	6. Receivables and Prepayments The amounts of outstanding receivables and prepayments at December 31, 2023 and 2022 are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31 2023 December 31 2022 Taxes and other receivables $ 467 $ 117 Prepayments ​ 1,511 ​ 2,609 ​ $ 1,978 $ 2,726 ​

Equipment

Equipment	12 Months Ended
	Dec. 31, 2023
Equipment.
Equipment	7. Equipment The movements in the Company’s capital equipment are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Exploration and ​ ​ ​ ​ Cost ​ other equipment ​ Office equipment ​ Total December 31, 2021 $ 2,800 ​ $ 21 ​ $ 2,821 Additions ​ 1,026 ​ — ​ 1,026 December 31, 2022 $ 3,826 ​ $ 21 ​ $ 3,847 Additions ​ 1,111 ​ — ​ 1,111 December 31, 2023 $ 4,937 ​ $ 21 ​ $ 4,958 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accumulated depreciation ​ ​ ​ December 31, 2021 $ (1,386) ​ $ (19) ​ $ (1,405) Amortization for the year ​ (416) ​ (1) ​ (417) December 31, 2022 $ (1,802) ​ $ (20) ​ $ (1,822) Amortization for the year ​ (359) ​ (1) ​ (360) December 31, 2023 $ (2,161) ​ $ (21) ​ $ (2,182) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net book value ​ ​ ​ ​ ​ ​ As at December 31, 2022 $ 2,024 ​ $ 1 ​ $ 2,025 As at December 31, 2023 $ 2,776 ​ $ — ​ $ 2,776 ​

Strategic Alliance with Allseas

Strategic Alliance with Allseas and Affiliates	12 Months Ended
	Dec. 31, 2023
Strategic Partnerships
Strategic Alliance with Allseas and Affiliates	8. Strategic Alliance with Allseas and Affiliates Pilot Mining Test Project On March 29, 2019, the Company and Allseas entered into a Strategic Alliance Agreement (“SAA”) with the objective to develop and operate commercial nodule collection systems in the Company’s contract areas. The SAA included the intent to develop and deploy a Pilot Mining Test System (“PMTS”), the successful completion of which would support the Company’s application for an exploitation contract with the ISA. Allseas committed to a fixed price development contract and would own all intellectual property used and generated in the development of the PMTS. Under the terms of the SAA, Allseas subscribed for and ultimately received 6.7 million common shares for a total of $20.0 million paid in cash to the Company. On July 8, 2019, as contemplated by the SAA, the Company and Allseas entered into the Pilot Mining Test Agreement (“PMTA”) which governs the terms, design specifications, procedures, and timetable under which Allseas agreed to complete a pilot trial of the PMTS in NORI Area D. Under the PMTA, in exchange for Allseas’ development efforts, upon successful delivery of the pilot trial of the PMTS in NORI Area D by Allseas, the Company agreed to pay Allseas: ● First milestone payment: $10 million within 10 business days of the closing of the Business Combination and Allseas providing confirmation of placing an order for certain equipment and demonstrating certain progress on construction of the PMTS; ● Second milestone payment: $10 million on the later of (i) January 1, 2022, and (ii) confirmation of successful completion of the North Sea drive test; ● Third milestone payment: $10 million upon successful completion of the pilot trial of the PMTS in NORI Area D; and ● 11.6 million warrants which would vest and become exercisable upon successful completion of the PMTS. On February 13, 2023, the Company entered into a Fifth Amendment to the Pilot Mining Test Agreement (the “PMTA”) and Third Amendment to the Strategic Alliance Agreement (together with the PMTA, the “Amendments”), which was effective as of February 8, 2023, with DGE, DeepGreen Metals ULC. and Allseas. The Amendments relate to the Company’s settlement of the third and final payment of $10 million due to Allseas upon successful completion of the trial of the PMTS in NORI Area D and certain other costs due to Allseas under the PMTA through the issuance of 10,850,000 common shares to Allseas, priced at $1.00 per share. On February 23, 2023, the Company settled the third milestone payment of $10 million and additional PMTS overage charges amounting to $0.9 million by issuing 10.85 million of its common shares to Allseas. On August 9, 2023, 11,578,620 common shares were issued to Allseas upon the exercise of the Allseas Warrant granted in March 2021, and receipt of the exercise fee of $115.8 thousand. The warrant vested and became exercisable on successful completion of the PMTS in November 2022 (refer Allseas Warrant, Note 13). Development of Project Zero Offshore Nodule Collection System On March 16, 2022, NORI and Allseas entered into a non-binding term sheet for the development and operation of a commercial nodule collection system. During the year ended December 31, 2023, in relation to the development of the commercial nodule collection system, Allseas provided the Company with engineering, project management and vessel use services consisting of lay-up and transit costs totaling $12.1 million, recorded as mining, technological and process development within exploration and evaluation expenses (Note 10). For the year ended December 31, 2022, Allseas managed and delivered the PMTS project, with services totaling $15.7 million, recorded as PMTS within exploration and evaluation expenses (Note 10). Exclusive Vessel Use Agreement with Allseas On August 1, 2023, the Company entered into an Exclusive Vessel Use Agreement with Allseas pursuant to which Allseas will give exclusive use of the vessel (“ Hidden Gem”) The Company concluded that the agreement was a lease, as the Hidden Gem was considered an identified asset and the Company had the right to direct the use of the Hidden Gem The Company recorded a lease liability For the year ended December 31, 2023, the Company has recognized $0.8 million as lease expense recorded as exploration and evaluation expense. As at December 31, 2023, the net amount of the lease liability ​ ​ ​ ​ ​ ​ Lease Liability Balance as at August 1, 2023 ​ $ 6,515 Payments made during the year by issuing 4.15 million common shares ​ 6,515 Balance as at December 31, 2023 ​ $ — ​ ​ ​ ​ ​ ​ Right-of-use Asset Balance as on August 1, 2023 ​ $ 6,515 Lease expense during the year ​ 794 Balance as at December 31, 2023 ​ $ 5,721 ​ Credit Facility with Allseas Affiliate On March 22, 2023, the Company entered into an Unsecured Credit Facility Agreement, which was amended on July 31, 2023 (“Credit Facility”), with Argentum Credit Virtuti GCV (the “Lender”), the parent of Allseas Investments S.A. and an affiliate of Allseas, pursuant to which, the Company may borrow from the Lender up to $25 million in the aggregate, from time to time, subject to certain conditions. All amounts drawn under the Credit Facility will bear interest based on the 6-month Secured Overnight Financing Rate, 180-day average plus a margin of 4.0% per annum payable in cash semi-annually (or plus 5% if paid-in-kind at maturity, at the Company’s election) on the first business day of each of June and January. The Company will pay an underutilization fee equal to 4.0% per annum payable semi-annually for any amounts that remain undrawn under the Credit Facility. The Company has the right to pre-pay the entire amount outstanding under the Credit Facility at any time before the Credit Facility’s maturity. The Company has the ability to settle the drawn credit facility, the interest on the drawn credit facility and underutilitzation fee in cash or in equity at discretion of the Company. On March 22, 2024, the maturity date of this Credit Facility was extended to August 31, 2025. The Credit Facility also contains customary events of default. During the year ended December 31, 2023, the Company had not drawn any amount from the Credit Facility and had incurred $0.8 million as underutilization fees, which would be payable only in the event the Credit Facility is not drawn down upon at the time such fees are payable. As at December 31, 2023, the amount payable to Allseas and its affiliates was $13.8 million (December 31, 2022: $10.2 million). Other Activity As a part of the Registered Direct Offering in August 2023 (Note 12), Allseas purchased 3,500,000 common shares and accompanying Class A Warrants to purchase 1,750,000 Common Shares (Note 13) for a total purchase price of $7 million. As at December 31, 2023, Allseas and its affiliates owned 53.8 million TMC common shares (2022: 23.7 million TMC common shares) which constituted 17.6% (December 31, 2022: 8.9%) of total common shares outstanding.

Investment in Low Carbon Royalt

Investment in Low Carbon Royalties	12 Months Ended
	Dec. 31, 2023
Strategic Partnerships
Investment in Low Carbon Royalties	9. On February 21, 2023 (the “Closing Date”), the Company and its wholly-owned subsidiary, NORI, entered into an investment agreement (the “Royalty Agreement”) with Low Carbon Royalties, a private corporation formed under the laws of British Columbia, Canada, to finance low carbon emitting energy production and technologies (natural gas, nuclear, renewables), transition metals and minerals required for energy storage and electrification (Cu, Li, Ni, Co, Mn), and the evolving environmental markets (the “Partnership”). In connection with the Royalty Agreement, NORI contributed a 2% gross overriding royalty (the “NORI Royalty”) on the Company’s NORI project area in the CCZ in which NORI currently holds exclusive exploration rights for polymetallic nodules from the ISA to Low Carbon Royalties. The Company retained the right to repurchase up to 75% of the NORI Royalty at an agreed capped return, exercisable in two transactions, between the second and the tenth anniversaries of the Partnership. If both repurchase transactions are executed, the NORI Royalty will be reduced to 0.5%. At the Closing Date, Low Carbon Royalties also owned a 1.56% gross overriding royalty on a producing natural gas field in Latin America (the “LCR-owned Royalty”). In consideration of the NORI Royalty, TMC received 35.0% of the common shares issued by Low Carbon Royalties and $5 million in cash, as of the Closing Date. In connection with the Royalty Agreement the Company entered into an Investor Rights Agreement with Low Carbon Royalties and a shareholder of Low Carbon Royalties, pursuant to which the Company and this shareholder each have a right, subject to certain percentage maintenance, to nominate a director to Low Carbon Royalties’ board of directors, along with registration and information rights. As a condition of closing the Royalty Agreement, the parties entered into an agreement with Low Carbon Royalties to mitigate risks associated with the potential termination of the exploitation license granted for one of the royalty-producing natural gas fields in Latin America (the “Exploitation License”). As per the agreement, 5 million contingent value rights (“CVR”) were issued to NORI. The CVR would convert into 5 million additional shares of Low Carbon Royalties being issued to NORI, in the event the Exploitation License is found, in a final decision, to be invalid by the Colombian National Agency of Hydrocarbons prior to the earlier of (1) five years from the issuance of the CVR and (2) the date Low Carbon Royalties becomes a publicly listed entity. Although the Company does not control Low Carbon Royalties (as per ASC 810), it does however exercise significant influence and therefore the equity method of accounting is applied (as per ASC 323). On March 21, 2023, Low Carbon Royalties acquired additional gross overriding royalties on natural gas fields in Latin America, increasing its total gross overriding royalty on the existing first license block from 1.56% to 3.13% and acquiring a new gross overriding royalty of 1.44% on a second license block. The royalty acquisitions were financed through the issuance of Low Carbon Royalties common shares to the third-party vendor of such royalties, thereby reducing the Company’s ownership in the Partnership to 32% from 35%. Based on the fair value of the NORI Royalty granted and the cash received, the Company recorded $9 million as investment in Low Carbon Royalties on the Closing Date. For the year ended December 31, 2023, the Company’s share of the net loss generated by the Low Carbon Royalties was $ 0.6 million. ​ ​ ​ ​ ​ ​ Investment Fair value of NORI Royalty ​ $ 14,000 Cash received ​ $ (5,000) Cost of Investment on Closing Date ​ $ 9,000 Equity-accounted investment loss for the year ​ (571) Investment as at December 31, 2023 ​ $ 8,429 ​ The NORI Royalty was recorded as a royalty liability in the consolidated Balance Sheet as this represented a sale of future revenues which falls within the scope of ASC 470, Debt ("ASC 470"). The Company elected to account for the royalty liability at fair value through profit and loss. The fair value was determined using a market approach which entails examining recent royalty transactions prior to the reporting date, focusing on those transactions that involve similar metals as contained in NORI’s polymetallic nodules. The Company compares the specific characteristics of these transactions to estimate the fair value. The fair value of the royalty liability as at December 31, 2023, remained unchanged at $14 million. Financial results of Low Carbon Royalties are summarized below: ​ ​ ​ ​ ​ ​ December 31 For the year ended ​ 2023 Current Assets ​ $ 1,091 Non-Current Assets ​ ​ 26,315 Current Liabilities ​ ​ 131 ​ ​ ​ ​ Royalty Income ​ $ 399 Total Revenue ​ 480 Comprehensive Income (Loss) for the year ​ $ (1,747) ​

Exploration Contracts

Exploration Contracts	12 Months Ended
	Dec. 31, 2023
Exploration Contracts.
Exploration Contracts	10. Exploration Contracts Significant Exploration Agreements NORI Exploration Contract: The Company’s wholly-owned subsidiary, NORI, was granted the NORI Exploration Contract on July 22, 2011 under the sponsorship of Nauru. The contract application fee of $0.3 million, provides NORI with exclusive rights to explore for polymetallic nodules in the NORI Area for an initial term of 15 years (renewable for successive five-year periods) subject to complying with the exploration contract terms (Note 19) and provides NORI with the priority right to apply for an exploitation contract to collect polymetallic nodules in the same area. NORI has a right to renounce, without penalty, in whole or part of its rights in the NORI Area at any time and therefore does not have a fixed commitment with relation to the NORI Exploration Contract (Note 19). Marawa Agreements: Marawa executed the Marawa Exploration Contract with the ISA on January 19, 2015. The Marawa Exploration Contract provides Marawa with exclusive rights to explore for polymetallic nodules in the Marawa Area for an initial term of 15 years (subject to renewal for successive five-year periods) subject to complying with the exploration contract terms and the priority right to apply for an exploitation contract to collect polymetallic nodules in the same area. On March 17, 2012, the Company’s wholly-owned subsidiary, DeepGreen Engineering Pte. Ltd. (“DGE”), entered into an Option Agreement (“Marawa Option Agreement”) with Marawa and Kiribati. DGE has the right to terminate the Marawa Services Agreement at its sole discretion by giving written notice to Marawa and Kiribati, and such termination shall take effect two months following the date of the termination notice, provided that DGE shall pay to the ISA on behalf of Marawa the fees or payments legally owed to the ISA by Marawa (including the annual ISA exploration fee and ISA royalties and taxes) that are outstanding at the date of termination or that are incurred within 12 months after the date of such termination. TOML Exploration Contract: TOML was granted the TOML Exploration Contract on January 11, 2012 under the sponsorship of Tonga. The TOML Exploration Contract provides TOML with exclusive rights to explore for polymetallic nodules in the TOML Area for an initial term of 15 years (renewable for successive five-year periods) subject to complying with the exploration contract terms and a priority right to apply for an exploitation contract to collect polymetallic nodules in the same area. On March 31, 2020, the Company entered into an acquisition agreement with Deep Sea Mining Finance Ltd. to acquire TOML and other related entities in the group (the “TOML Acquisition”). Total purchase price of the TOML Acquisition, before transaction costs, was $32.0 million comprising of $42.7 million for exploration contracts offset by $10.7 million for deferred tax liability. TOML holds an ISA exploration contract in the CCZ (“TOML Exploration Contract”) and some exploration related equipment. Reconciliation – Exploration Contracts A reconciliation of the Company’s capitalized exploration contracts is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Marawa ​ ​ ​ ​ ​ ​ NORI ​ Option ​ TOML ​ ​ ​ ​ ​ Contract ​ Agreement ​ Contract ​ Total December 31, 2022 $ 250 ​ $ 199 ​ $ 42,701 ​ $ 43,150 December 31, 2023 $ 250 ​ $ 199 ​ $ 42,701 ​ $ 43,150 ​ Exploration and Evaluation Expenses The detail of exploration and evaluation expenses is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ NORI Marawa TOML ​ ​ ​ ​ Exploration ​ Option ​ Exploration ​ ​ ​ For the year ended December 31, 2023 ​ Contract ​ Agreement ​ Contract ​ Total Environmental Studies ​ $ 16,421 ​ $ — ​ $ — ​ $ 16,421 Exploration Labor ​ ​ 7,268 ​ ​ 227 ​ ​ 711 ​ ​ 8,206 Share-Based Compensation (Note 15) ​ 4,444 ​ 146 ​ 443 ​ 5,033 Mining, Technological and Process Development ​ ​ 13,694 ​ ​ — ​ ​ 1,262 ​ ​ 14,956 Prefeasibility Studies ​ ​ 1,345 ​ ​ — ​ ​ — ​ ​ 1,345 Sponsorship, Training and Stakeholder Engagement (1) ​ ​ 2,248 ​ ​ 202 ​ ​ 996 ​ ​ 3,446 Other ​ 433 ​ — ​ 9 ​ 442 ​ ​ $ 45,853 ​ $ 575 ​ $ 3,421 ​ $ 49,849 (1) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ NORI Marawa TOML ​ ​ ​ ​ Exploration ​ Option ​ Exploration ​ ​ ​ For the year ended December 31, 2022 ​ Contract ​ Agreement ​ Contract ​ Total Environmental Studies ​ $ 38,022 ​ $ — ​ $ — ​ $ 38,022 Exploration Labor ​ ​ 4,420 ​ ​ 758 ​ ​ 842 ​ ​ 6,020 Share-Based Compensation (Note 15) ​ 6,086 ​ 1,167 ​ 1,235 ​ 8,488 Mining, Technological and Process Development ​ ​ 1,823 ​ ​ 47 ​ ​ 118 ​ ​ 1,988 PMTS ​ ​ 15,603 ​ ​ 670 ​ ​ 1,546 ​ ​ 17,819 Allseas Warrant (Note 13) ​ 62,910 ​ — ​ 6,990 ​ 69,900 Sponsorship, Training and Stakeholder Engagement ​ ​ 891 ​ ​ 194 ​ ​ 476 ​ ​ 1,561 Other ​ ​ 706 ​ ​ 16 ​ ​ 79 ​ ​ 801 ​ ​ $ 130,461 ​ $ 2,852 ​ $ 11,286 ​ $ 144,599 ​

General and Administrative Expe

General and Administrative Expenses	12 Months Ended
	Dec. 31, 2023
General and Administrative Expenses
General and Administrative Expenses	11. ​ ​ ​ ​ ​ ​ ​ ​ ​ For the year ended For the year ended ​ ​ December 31, ​ December 31, ​ ​ 2023 ​ 2022 Professional and consulting fees (1) ​ $ 6,584 ​ $ 6,795 Investor relations (2) ​ 1,547 ​ 1,514 Office and sundry ​ 3,503 ​ 4,926 Salaries and wages ​ 4,995 ​ 5,921 Director fees ​ 774 ​ 788 Share-based compensation ​ 4,122 ​ 8,596 Transfer agent and filing fees ​ 363 ​ 378 Travel expenses ​ 609 ​ 600 Other expenses ​ 43 ​ — General and Administrative Expenses ​ $ 22,540 ​ $ 29,518 (1) (2)

Financing activity

Financing activity	12 Months Ended
	Dec. 31, 2023
Financing Activity
Financing Activity	12. Registered Direct Offering On August 14, 2023, the Company entered into a securities purchase agreement with certain investors, pursuant to which the Company agreed to sell and issue, in a registered direct offering (the “Registered Direct Offering”) 12,461,540 common shares and issue Class A Warrants to purchase 6,230,770 common shares (Note 13). Each common share and accompanying Class A Warrant were sold at a price of $2.00 per unit. The exercise price to purchase one common share under the Class A warrants is $3.00, subject to adjustment as provided in the warrant agreement. The aggregate gross proceeds to the Company from the Registered Direct Offering were expected to be approximately $24.9 million, before deducting fees payable to financial advisors and other estimated offering expenses payable by the Company ($23.6 million net of fees). As at December 31, 2023, 7,961,540 common shares and Class A Warrants to purchase 3,980,770 common shares had been issued and the Company received gross proceeds amounting to $15.9 million. The Company incurred $1.3 million as offering expenses, resulting in net proceeds received of $14.6 million. Out of the total net proceeds received of $14.6 million, the net proceeds attributable to common shares were $11.4 million and the net proceeds attributable to Class A Warrants were $3.2 million. On January 30, 2024, the Company received the remaining committed funding of $9 million (representing 4,500,000 common shares and 2,250,000 warrants) from an investor affiliated with the Company. The common shares and warrants were issued on January 31, 2024. PIPE Financing On August 12, 2022, the Company entered into three securities purchase agreements for the private placement of an aggregate of 37,978,680 of the Company’s common shares. As at December 31, 2022, all of the 37,978,680 shares were issued and the Company received gross proceeds amounting to $30.4 million. The Company incurred $1.0 million as placement agent fees and offering expenses out of which expenses amounting to $0.2 million were settled by issuing 287,500 shares at an issue price of $0.80 per share.

Warrants

Warrants	12 Months Ended
	Dec. 31, 2023
Warrants
Warrants	13. Public Warrants Each whole Public Warrant entitles the holder to purchase one TMC common share at a price of $11.50 per share beginning on October 9, 2021, subject to restrictions described below. As at December 31, 2023, 15,000,000 Public Warrants were outstanding. Public Warrants may only be exercised for a whole number of shares. No fractional Public Warrants will be issued upon separation of the units and only whole Public Warrants will trade. The Public Warrants will expire on September 9, 2026 or earlier upon redemption or liquidation. Public Warrant holders do not have the rights or privileges of holders of common shares nor any voting rights until they exercise their warrants and receive common shares. The Company will not be obligated to deliver any common shares pursuant to the exercise of a Public Warrant and will have no obligation to settle such warrant exercise unless a registration statement under the Securities Act of 1933, as amended (“Securities Act”) with respect to the common shares underlying the Public Warrants is then effective and a prospectus relating thereto is current, subject to the Company satisfying its obligations with respect to registration, or a valid exemption from registration is available. No Public Warrants will be exercisable and the Company will not be obligated to issue a common share upon exercise of a Public Warrant unless the common share issuable upon such warrant exercise has been registered, qualified or deemed to be exempt under the securities laws of the state of residence of the registered holder of the warrants. In the event that the conditions in the two immediately preceding sentences are not satisfied with respect to a Public Warrant, the holder of such warrant will not be entitled to exercise such warrant and such warrant may have no value and expire worthless. In no event will the Company be required to net cash settle any Public Warrants. In the event that a registration statement is not effective for the exercised Public Warrants, the purchaser of a unit containing such warrant will have paid the full purchase price for the unit solely for the common share underlying such unit. The Company may call the Public Warrants for redemption: ● in whole and not in part; ● at a price of $0.01 per warrant; ● upon a minimum of 30 days ’ prior written notice of redemption; and ● if, and only if, the closing price of the common shares equals or exceeds $18.00 per share (as adjusted for share subdivisions, share capitalizations, reorganizations, recapitalizations and the like) for any 20 trading days within a 30 - day trading period ending on the third trading day prior to the date on which the Company sends the notice of redemption to the warrant holders. If the Company calls the Public Warrants for redemption in certain circumstances, management will have the option to require all holders that wish to exercise the Public Warrants to do so on a cashless basis, by surrendering the Public Warrants for a number of common shares per warrant equal to the lesser of: ● the quotient obtained by dividing (x) the product of the number of common shares underlying such warrant, multiplied by the excess of the average reported closing price of common shares for the ten trading days ending on the third trading day prior to the date on which the notice of redemption is sent to the holders (“Fair Market Value”) over the warrant price by (y) the Fair Market Value, and ● 0.365 . Private Warrants As at December 31, 2023, 9,500,000 Private Warrants were outstanding. The Private Warrants (including the common shares issuable upon exercise of the Private Warrants) were not transferable, assignable or salable until October 9, 2021, except to permitted transferees. The Private Warrants are identical to the Public Warrants, except that so long as they are held by the Sponsor or any of its permitted transferees: (i) the Private Warrants are exercisable for cash or on a cashless basis, at the holder’s option, and (ii) the Private Warrants are not redeemable by the Company. The Private Warrants are subject to the Company’s redemption option at the price of $0.01 per warrant, if not held by the Sponsor or any of its permitted transferees, provided that the other conditions of such redemption are met, as described above. If holders of the Private Warrants elect to exercise the warrants on a cashless basis, the holder would pay the exercise price by surrendering their Private Warrants for a number of common shares equal to: ● the quotient obtained by dividing (x) the product of the number of common shares underlying the warrants, multiplied by the excess of the average reported closing price of the common shares for the ten trading days ending on the third trading day prior to the date on which the notice of warrant exercise is sent to the warrant agent (“fair market value”) over the exercise price of the warrants by (y) the fair market value. If the Private Warrants are held by a holder other than the Sponsor or any of its permitted transferees, the Private Warrants are redeemable by the Company in all redemption scenarios applicable to the Public Warrants and exercisable by such holders on the same basis as the Public Warrants. The Company evaluated the Private Warrants under ASC 815-40, in conjunction with the SEC Statement , The Private Warrants were valued using a Black-Scholes model, which resulted in a Level 3 fair value measurement. The primary unobservable input utilized in determining the fair value of the Private Warrants was the expected volatility of the Company’s common shares. As the Company’s shares reached their two-year trading anniversary on September 9, 2023, the Company changed its approach in calculating volatility from solely the implied volatility of the Company’s Public Warrants to now include an equal weight blend of the Public Warrants volatility and the historical volatility of the Company’s share price. The expected volatility was estimated using a binomial model based on consideration of the implied volatility from the Company’s Public Warrants adjusted to account for the call feature of the Public Warrants at prices above $18.00 during 20 trading days within any 30-day trading period and historical volatility of the share price of the common shares. As at December 31, 2023, the fair value of outstanding Private Warrants of approximately $2 million is recorded as warrants liability. The following table presents the changes in the fair value of warrants liability: ​ ​ ​ ​ ​ ​ Private ​ ​ Warrants Warrants liability as at December 31, 2022 ​ $ 983 Increase in fair value of warrants liability ​ 986 Warrants liability as at December 31, 2023 ​ $ 1,969 ​ As at December 31, 2023, the fair value of the Private Warrants was estimated using the following assumptions: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023 December 31, 2022 ​ Exercise price ​ $ 11.50 ​ $ 11.50 ​ Share price ​ $ 1.10 ​ $ 0.77 ​ Volatility (1) ​ 105.34 % ​ 88.05 % Term ​ 2.69 years ​ 3.69 years Risk-free rate ​ 3.98 % ​ 4.04 % Dividend yield ​ 0.0 % ​ 0.0 % 1. The Company used a blended volatility approach to calculate the fair value of the warrants on December 31, 2023 by assigning equal weights to both implied volatility of the Company’s Public Warrants and the historical volatility of the share price. The volatility used in calculating the fair value of the warrants as at December 31, 2022 comprised only of the implied volatility of the Company’s Public Warrants. There were no exercises or redemptions of the Public Warrants or Private Warrants during the year ended December 31, 2023. Allseas Warrant The Allseas Warrant that was granted on March 4, 2021, vested and became exercisable for 11.6 million common shares upon successful completion of the PMTS in November 2022. The Company recognized a charge of $69.9 million in the fourth quarter of 2022, representing the fair market value of the Allseas Warrant on the date it was granted. On July 26, 2023, the Allseas Warrant was exercised resulting in the issuance of 11,578,620 common shares of the Company on August 9, 2023, once the exercise amount of $115.8 thousand was received from Allseas (Note 8). Class A Warrants As a part of the Registered Direct Offering (Note 12), the Company issued 3,980,770 Class A Warrants for the purchase of common shares at an exercise price of $3.00 per share. The Class A Warrants expire on December 31, 2027. The valuation of these Class A Warrants was determined using a Monte Carlo simulation. ​ The Class A Warrants were valued on August 14, 2023, at a fair value of $0.80 per warrant. The fair value of the Class A Warrants was estimated using the following assumptions: ​ ​ ​ ​ ​ ​ ​ August 14, ​ ​ 2023 ​ Exercise price ​ $ 3.00 ​ Share price ​ $ 1.41 ​ Call price threshold ​ $ 6.50 ​ Volatility ​ 107.08 % Term (years) ​ 4.38 ​ Risk-free rate ​ 4.32 % Dividend yield ​ 0.0 % ​ The Class A Warrants contain a call provision under which if the Volume Weighted Average Price “VWAP” for 30 consecutive trading days exceeds $6.50, and the warrant holder does not possess material non-public information provided by the Company, the Company may call for cancellation of the unexercised warrants, offering $0.0001 per Warrant Share. If conditions for the call are met, the unexercised portion of these warrants will be cancelled ten The Class A Warrants were not determined to be liabilities under ASC 480 as they were not required to be redeemed. The Company classified the Class A Warrants as equity (per ASC 815), as the warrants entailed physical settlement and were also considered to be indexed to the Company’s share, wherein, upon exercise, a fixed number of common shares would be issued on payment of a fixed exercise price. As at December 31, 2023, the Company recorded $3.2 million as additional paid in capital. On January 31, 2024, the Company issued the remaining 2,250,000 Class A Warrants, after receiving the remaining committed funding from the Registered Direct Offering of $9 million (Notes 12 and 22).

Common Shares

Common Shares	12 Months Ended
	Dec. 31, 2023
Common Shares
PIPE Financing	14. Authorized and Issued As at December 31, 2023, the authorized, issued and outstanding common shares and Special Shares of the Company are as follows: ​ ​ ​ ​ ​ ​ ​ Issued and ​ ​ Authorized ​ Outstanding Common shares Unlimited, with no par value 306,558,710 Class A Special Shares 5,000,000, with no par value 4,448,259 Class B Special Shares 10,000,000, with no par value 8,896,399 Class C Special Shares 10,000,000, with no par value 8,896,399 Class D Special Shares 20,000,000, with no par value 17,792,922 Class E Special Shares 20,000,000, with no par value 17,792,922 Class F Special Shares 20,000,000, with no par value 17,792,922 Class G Special Shares 25,000,000, with no par value 22,241,179 Class H Special Shares 25,000,000, with no par value 22,241,179 Class I Special Shares 500,000, with no par value 500,000 Class J Special Shares 741,000, with no par value 741,000 ​ The holders of the Company’s common shares are entitled to one vote for each common share held. Each class of Special Shares do not have voting rights and do not participate in earnings. The Special Shares automatically convert to TMC common shares if TMC common shares trade at a price on any 20 trading days within any 30-trading day period that is greater than or equal to the specific trigger price for the respective class of Special Share. Below is a summary of the Special Shares and their respective vesting thresholds, assuming the full amount of Special Shares from Rollover Options are issued: ​ Special Share Class A B C D E F G H I J Share Trigger price ($) 15 25 35 50 75 100 150 200 50 12 Special Shares (million) 5 10 10 20 20 20 25 25 0.5 0.7 ​ As the Special Shares meet the indexation and equity classification criteria under ASC 815-40, the Special Shares have been classified as equity instruments at issuance. Common Share Continuity ​ ​ ​ ​ ​ ​ ​ Common shares Number Amount December 31, 2021 225,432,493 ​ $ 296,051 Issuance of shares under PIPE financing (Note 12) 38,266,180 ​ ​ 29,621 Exercise of stock options (Note 15) 118,461 ​ ​ 142 Conversion of restricted share units ​ 2,877,068 ​ ​ 6,875 Share purchase under Employee Stock Purchase Plan (Note 15) 117,929 ​ ​ 193 December 31, 2022 266,812,131 ​ $ 332,882 Issuance of shares under Registered Direct Offering (Note 12) 7,961,540 ​ ​ 11,420 Exercise of warrant by Allseas (Note 13) ​ 11,578,620 ​ ​ 70,016 Shares issued to Allseas (Notes 8) ​ 15,000,000 ​ ​ 15,910 Exercise of stock options (Note 15) ​ 120,000 ​ ​ 144 Conversion of restricted share units (Note 15) ​ 4,912,747 ​ ​ 7,720 Share purchase under Employee Stock Purchase Plan (Note 15) ​ 173,672 ​ ​ 147 December 31, 2023 306,558,710 ​ $ 438,239 ​

Share-Based Compensation

Share-Based Compensation	12 Months Ended
	Dec. 31, 2023
Share-Based Compensation
Share-Based Compensation	15. The Company’s 2021 Incentive Equity Plan (the “Plan”) provides that the aggregate number of common shares reserved for future issuance under the Plan as of December 31, 2023, is 44,372,170 common shares, including 10,672,485 shares added to the Plan in January 2023 pursuant to the Plan’s automatic annual increase provision, provided that 2,243,853 of the outstanding common shares shall only be available for awards made to non-employee directors of the Company. On the first day of each fiscal year beginning in 2022 to the tenth anniversary of the closing of the Business Combination, the number of common shares that may be issued pursuant to the Plan is automatically increased by an amount equal to the lesser of 4% of the number of outstanding common shares or an amount determined by the board of directors. Stock options Pursuant to the Company’s stock option plan, directors may, from time to time, authorize the issuance of stock options to directors, officers, employees, and consultants of the Company and its subsidiaries. The board of directors grants such options with vesting periods and exercise prices determined at its sole discretion. As at December 31, 2023, there were 15,074,240 stock options outstanding under the Company’s Short-Term Incentive Plan (“STIP”) and 9,783,922 stock options outstanding under the Company’s Long-Term Incentive Plan (“LTIP”). The Company makes awards under the STIP and LTIP under its equity incentive plans in effect at the time of the award, which is currently the Plan. No new stock Outstanding under STIP plan A continuity schedule summarizing the movements in the Company’s stock options under the STIP plan is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ Aggregate ​ Weighted ​ ​ average intrinsic average ​ ​ Number of ​ exercise ​ value of ​ contractual ​ ​ Options ​ price per ​ stock ​ life ​ ​ Outstanding ​ option ​ options ​ (years) Outstanding – December 31, 2021 15,503,748 ​ $ 1.40 $ 17,415 ​ 6.33 Cancelled/Forfeited (28,947) ​ ​ 2.60 ​ — ​ — Exercised (118,461) ​ ​ 0.65 ​ — ​ — Outstanding – December 31, 2022 15,356,340 ​ $ 1.40 $ 1,582 ​ 5.11 Granted — ​ ​ — ​ — ​ — Expired (162,100) ​ ​ 0.87 ​ — ​ — Cancelled/Forfeited — ​ ​ — ​ — ​ — Exercised (120,000) ​ ​ 0.65 ​ — ​ — Outstanding – December 31, 2023 15,074,240 ​ $ 1.41 $ 5,425 ​ 4.18 Vested and exercisable – December 31, 2023 14,804,073 ​ $ 1.28 $ 5,425 ​ 4.17 ​ A summary of the Company’s stock options granted and outstanding under the Company’s STIP as at December 31, 2023 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average Number of Number of ​ ​ ​ ​ ​ life to expiry ​ Options ​ Options Expiry Date ​ Exercise price ​ (years) ​ Outstanding ​ Exercisable March 31, 2024 ​ $ 0.65 0.25 73,811 73,811 December 31, 2025 ​ $ 0.65 2.00 11,578 11,578 January 27, 2026 ​ $ 0.52 - $2.59 2.08 975,229 975,229 February 2, 2026 ​ $ 0.65 2.09 57,893 57,893 February 17, 2026 ​ $ 0.22 - $0.52 2.13 431,494 431,494 June 1, 2028 ​ $ 0.65 - $8.64 4.42 12,829,518 12,559,351 June 30, 2028 ​ $ 2.59 4.50 694,717 694,717 ​ ​ ​ ​ ​ ​ 15,074,240 14,804,073 ​ The total grant date fair value of STIP stock options that vested during the year ended December 31, 2023, was $1.5 million. As at December 31, 2023, total unrecognized share-based compensation expense of $47 thousand is expected to be recognized over a weighted-average recognition period of approximately one year. As at December 31, 2023, the closing market price of the Company’s common shares was $1.10 per share which was considered to be the fair value of the Company’s common share used to determine the intrinsic value of outstanding stock options. The aggregate intrinsic value of stock options exercised during the year ended December 31, 2023 was $188 thousand. Outstanding under LTIP plan: On March 4, 2021, the Company granted 9,783,922 stock options under its LTIP. These stock options have an exercise price of $0.65 per option and expire on June 1, 2028. The LTIP awards vest as follows: (1) Tranche 1 - 25 % when the Company’s market capitalization equals $ 3 billion; (2) Tranche 2 - 35 % when the Company’s market capitalization equals $ 6 billion; (3) Tranche 3 - 20 % upon the date that the ISA grants an exploitation contract to the Company; and (4) Tranche 4 - 20 % upon the commencement of the first commercial production following the grant of the exploitation contract. Tranche 1 and Tranche 2 vest based on the Company’s market capitalization of $3 billion and $6 billion, respectively. Accordingly, these options are determined to be market-based awards for which the Company has calculated fair value and derived a service period through which to expense the related fair value. The options included in Tranche 1 and Tranche 2 had a grant date fair value of $5.59 per share and $5.42 per share and derived service periods of 0.33 years and 1.41 years, respectively. The Company will expense these awards ratably over the remaining service period. Tranche 3 and Tranche 4 of the LTIP stock options vest based on the date the ISA grants an exploitation contract and the commencement of commercial production. These options are determined to be performance-based awards. The Company will recognize compensation costs for the performance-based awards if and when the Company concludes that it is probable that the performance conditions will be achieved. As at December 31, 2023, no compensation expense related to the performance based awards was recorded as the awarding of an ISA contract is outside the control of the Company. The Company will reassess the probability of the vesting of the performance-based awards at each reporting period and adjust the compensation cost when determined to be probable. The aggregate intrinsic value of LTIP stock options as at December 31, 2023 was $4.4 million. None of the LTIP stock options were exercisable on December 31, 2023. The Company expects LTIP options to vest as and when the market and performance milestones described below are achieved. As at December 31, 2023, total unrecognized share-based compensation expense for the LTIP stock options was $23 million. During the year ended December 31, 2023, the Company recognized $0.5 million of share-based compensation expense for stock options (originally issued under STIP and LTIP plans) in the statement of loss and comprehensive loss (2022: $9.5 million). Share-based compensation expense for stock options totaling $0.3 million related to general and administration matters were charged to the statement of loss and comprehensive loss for the year ended December 31, 2023 (2022: $4.8 million). The Company recorded a total of $0.2 million of share-based compensation expense for stock options related to exploration and evaluation activities for the year ended December 31, 2023 (2022: $4.7 million). Restricted Share Units The Company may, from time to time, grant RSUs to directors, officers, employees, and consultants of the Company and its subsidiaries under the Plan. On each vesting date, RSU holders are entitled to receive common shares equivalent to the number of RSUs held provided the holder is providing service to the Company on such vesting date. ​ The details of RSUs granted by the Company during the year are as follows: ​ ​ ​ ​ ​ ​ Vesting Period 2023 2022 Vesting Immediately (1)(2) 3,561,078 1,721,729 Vesting fully on the anniversary of the grant date (3) 1,014,349 476,189 Vesting in thirds on each anniversary of the grant date (4) 8,689,481 464,632 Vesting in fourths on each anniversary of the grant date 404,277 527,800 Total Units Granted 13,669,185 3,190,350 1. Of the 3,561,078 units vesting immediately on grant date, 3,198,648 units were issued to settle liabilities with a carrying amount of $2.8 million, at a weighted average grant date fair value of $0.89 per RSU. 2. During the year ended December 31, 2023, the Company granted 274,912 units to consultants (2022: 649,157 units) resulting in $0.3 million, charged to professional and consulting fees under general and administrative expenses and $ 11 thousand charged to exploration and evaluation activities for the year ended December 31, 2023 (2022: $1.2 million of general and administrative expenses). During the year ended December 31, 2023, the Company also granted 43,478 units to consultants as a prepayment for their services (2022: nil ). 3. During the year ended December 31, 2023, the Company granted 1,014,349 RSUs (2022: 476,189 ) to its non-employee directors under the Company’s Non-employee Director Compensation Policy, which vest upon the Company’s 2024 annual shareholders meeting. The total fair value of units granted as annual grants to the non-employee directors amounted to $700,000 ( $700,000 in 2022). 4. During the year ended December 31, 2023, the Company granted 8,645,465 units, as payment for the 2022 LTIP awards and 44,016 units as a sign-on grant. The 2021 LTIP awards were granted in the fourth quarter of 2021 and totaled 3,500,000 units. A summary of the RSU activity in 2023 is presented in the table below: ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ Number of ​ average grant- ​ ​ RSUs ​ date fair value ​ ​ Outstanding ​ per RSU Outstanding – December 31, 2022 3,815,143 $ 2.75 Granted 13,669,185 ​ 0.92 Forfeited ​ (86,700) ​ ​ 0.96 Exercised ​ (4,912,748) ​ ​ 1.57 Outstanding – December 31, 2023 12,484,880 $ 1.23 ​ The grant date fair value of RSUs is equivalent to the closing share price of the Company’s common shares on the date of grant. During the year, a total of $8.6 million was charged to the statement of loss and comprehensive loss as share-based compensation expense for RSUs (2022: $7.5 million). Share-based compensation expense for RSUs totaling $3.8 million related to general and administration matters was charged to the statement of loss and comprehensive loss for the year ended December 31, 2023 (2022: $3.8 million). The Company recorded a total of $4.8 million of share-based compensation expense for RSUs related to exploration and evaluation activities for the year ended December 31, 2023 (2022: $3.7 million). As at December 31, 2023, total unrecognized share-based compensation expense for RSUs was $6.9 million (December 31, 2022 - $6.1 million). The fair value of shares vested during the year ended December 31, 2023, amounted to $8.3 million (December 31, 2022 - $7.2 million). As at December 31, 2023, an aggregate of 746,445 vested units were being processed and due to be converted into common shares. Employee Stock Purchase Plan On May 31, 2022, TMC’s 2021 Employee Stock Purchase Plan (“ESPP”) was approved at the Company’s 2022 annual shareholders meeting. As of December 31, 2023, there were 7,922,445 common shares reserved for issuance under the ESPP. This included 2,668,121 shares added to the ESPP in January 2023 pursuant to the ESPP’s automatic annual increase provision discussed below. Under the ESPP, the number of shares reserved for issuance is subject to an annual increase provision which provides that on the first day of each of the Company’s fiscal years starting in 2022, common shares equal to the lesser of (i) 1% percent of the common shares outstanding on the last day of the immediately preceding fiscal year, or (ii) such lesser number of shares as is determined by the board of directors will be added to the ESPP. Participation in the ESPP is available to all full-time and certain part-time employees, subject to certain conditions. The ESPP comprises offering periods that are twenty-four (24) months in length, which begin on approximately every June 1 and December 1. Each offering period includes four purchase periods of six months each, which begin on approximately every June 1 and December 1, or at such other times designated by the board of directors or its compensation committee. At the exercise date, which is the last business day of each purchase period, the accumulated deductions from participating employees are used to purchase common shares of the Company. Shares are purchased at a price equal to 85% of the lower of either the share price of the Company’s common shares on the first business day of the particular offering period or the last business day of the purchase period. The ESPP also has an automatic reset feature wherein, if the share price of the common share on any exercise date is less than the share price of the common share on the first business day of the applicable offering period, then such offering period shall automatically terminate immediately after the purchase of the common shares. In such case, a new offering period shall commence on the first business day following the exercise date. The ESPP includes the following limitations: ● an employee’s contribution is limited to 15% of the employee’s annual gross earnings, not to exceed $25,000 per year, ● an employee’s purchases in any offering period cannot exceed 15,000 common shares, and ● an employee’s purchases are capped, not to exceed 5% of the Company’s total outstanding common shares. During 2023, the Company issued 173,672 common shares (2022: 117,929 common shares) to its employees as part of its ESPP program. A total of $47 thousand was charged to the statement of loss and comprehensive loss as share-based compensation expense for the year ended December 31, 2023, representing the share price purchase discount offered by the Company (2022: $0.1 million). From the amount charged in 2023, $26 thousand was recorded in exploration and evaluation expenses (2022: $35 thousand) and $21 thousand was recorded in general and administrative expenses (2022: $67 thousand).

Loss per Share

Loss per Share	12 Months Ended
	Dec. 31, 2023
Loss per Share
Loss per Share	16. Basic loss per share is computed by dividing the loss by the weighted-average number of common shares of the Company outstanding during the period. Diluted loss per share is computed by giving effect to all common share equivalents of the Company, including outstanding stock options, RSUs, warrants, Special Shares and options to purchase Special Shares, to the extent these are dilutive. Basic and diluted loss per share was the same for each period presented as the inclusion of all common share equivalents would have been anti-dilutive. Anti-dilutive equivalent common shares were as follows: ​ ​ ​ ​ ​ ​ ​ ​ For the year ended ​ For the year ended ​ ​ December 31, ​ December 31, ​ 2023 2022 Outstanding options to purchase common shares ​ 24,858,162 ​ 25,140,262 Outstanding RSUs 12,484,880 3,815,143 Outstanding shares under ESPP ​ 8,802 ​ 12,212 Outstanding warrants 28,480,770 36,078,620 Outstanding Special Shares and options to purchase Special Shares 136,239,964 136,239,964 Total anti-dilutive common equivalent shares 202,072,578 201,286,201 ​

Financial Instruments

Financial Instruments	12 Months Ended
	Dec. 31, 2023
Financial Instruments
Financial Instruments	17. Financial Instruments Categories of Financial Instruments ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023 December 31, 2022 Financial assets ​ ​ Amortized cost ​ ​ Cash $ 6,842 $ 46,876 Receivables and Prepayments ​ ​ 1,978 ​ ​ 2,726 ​ $ 8,820 $ 49,602 ​ ​ ​ ​ ​ ​ ​ Financial liabilities ​ ​ Amortized cost ​ ​ Accounts payable and accrued liabilities $ 31,334 $ 41,614 Fair value through profit or loss ​ — ​ ​ — Royalty liability ​ ​ 14,000 ​ ​ — Warrants liability ​ ​ 1,969 ​ ​ 983 ​ $ 47,303 $ 42,597 ​

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2023
Related Party Transactions
Related Party Transactions	18. The Company’s subsidiary, DeepGreen Engineering Pte. Ltd., is engaged in a consulting agreement with SSCS Pte. Ltd. (“SSCS”) to manage offshore engineering studies. A director of DGE is employed through SSCS. Consulting services during the year ended December 31, 2023 totaled $212 thousand, (2022: $275 thousand), out of which a total $170 thousand (2022: $220 thousand), is disclosed as exploration labor within exploration and evaluation expenses (Note 10) and $42 thousand is disclosed as general and administrative expenses (2022: $55 thousand). As at December 31, 2023, the amount payable to SSCS was $17 thousand (December 31, 2022 - $17 thousand). The Company’s Chief Ocean Scientist provides consulting services to the Company through Ocean Renaissance LLC (“Ocean Renaissance”) where he is a principal. Consulting services during year ended December 31, 2023 amounted to $331 thousand (2022: $375 thousand), out of which $149 thousand (2022 $188 thousand:), is disclosed as exploration labor within exploration and evaluation expenses (Note 10) and $182 thousand is disclosed as general and administrative expenses (2022: $187 thousand). As at December 31, 2023, the amount payable to Ocean Renaissance was $25 thousand (December 31, 2022- $nil). The Registered Direct Offering announced on August 14, 2023, included approximately $0.3 million from the participation of several of the Company’s Directors and Officers. In addition, the committed funding included $10 million from ERAS Capital LLC, the investment fund of one of the Company’s Directors, $1 million of which was received on August 16, 2024 and the remaining $9 million was received on January 30, 2024 (Note 12). Apart from the above-mentioned transactions, the Company had transactions with Allseas which are detailed in Note 8.

Commitments and Contingent Liab

Commitments and Contingent Liabilities	12 Months Ended
	Dec. 31, 2023
Commitments and Contingent Liabilities
Commitments and Contingent Liabilities	19. NORI Exploration Contract As part of the NORI Exploration Contract with the ISA, NORI submitted a periodic review report to the ISA in 2021, covering the 2017-2021 period. The periodic review report, which included a proposed work plan and estimated budget for 2022 to 2026, has been reviewed by and agreed with the ISA, and the Company is implementing the five-year plan. The cost of the estimated work plan for 2024 onwards is dependent on the ISA’s approval of the NORI Area D exploitation application. Should the approval of NORI’s exploitation application for NORI Area D be delayed or rejected, NORI intends to revise its estimated future work plan in respect of its NORI Area. Work plans are reviewed annually by the Company, agreed with the ISA and may be subject to change depending on the Company’s progress to date. Marawa Option Agreement and Services Agreement Through DGE’s Marawa Option Agreement and separate Services Agreement with Marawa with respect to the Marawa Area, Marawa and DGE submitted a periodic review report to the ISA in 2019, covering 2015-2019. The periodic review report includes a proposed work plan and estimated budget for the 2020-2024 five-year period. The five-year estimated expenditure is indicative and subject to change, Marawa will review the program regularly and Marawa will inform the ISA of any changes through its annual reports. To date, limited offshore marine resource definition activities in the Marawa Contract Area have occurred. The Company expects to collaborate with Marawa to assess the viability of any potential project in the Marawa Contract Area, although the timing of such assessment is unclear. Marawa has delayed certain of its efforts in the Marawa Contract Area while it determines how it will move forward with additional assessment work. TOML Exploration Contract As part of the TOML Exploration Contract, TOML submitted a periodic review report to the ISA in 2021, covering the 2017-2021 period. The periodic review report included a summary of work completed over the five-year period and a program of activities and estimated budget for the next five-year period. On December 23, 2022, the ISA accepted TOML’s proposed program of activities for the 2022-2026 five-year period, which included an estimated five-year expenditure of up to $44 million. The five-year estimated expenditure is indicative and subject to change, TOML will review the program regularly and TOML will inform the ISA of any changes through its annual reports. Offtake Agreements On May 25, 2012, the Company’s wholly-owned subsidiary, DGE, and Glencore International AG (“Glencore”) entered into a copper offtake agreement and a nickel offtake agreement. DGE has agreed to deliver to Glencore 50% of the annual quantity of copper and nickel produced at a DGE-owned processing facility from nodules derived from the NORI Area at London Metal Exchange referenced market pricing with allowances for product quality and delivery location. Both the copper and nickel offtake agreements are for the life of the Company’s rights to the NORI Area. Either party may terminate the agreement upon a material breach or insolvency of the other party. Glencore may also terminate the agreement by giving twelve months’ notice. Sponsorship Agreements On July 5, 2017, Nauru, the Nauru Seabed Minerals Authority and NORI entered into a sponsorship agreement formalizing certain obligations of the parties in relation to NORI’s exploration and potential exploitation of the NORI Area. Upon reaching the minimum recovery level within the exploitation contract area, NORI will pay Nauru a seabed mineral recovery payment based on the polymetallic nodules recovered from the exploitation contract area. In addition, NORI will pay an administration fee each year to Nauru for such administration and sponsorship, which is subject to review and increase in the event NORI is granted an ISA exploitation contract. NORI has begun discussions with the Government of Nauru to renegotiate the existing sponsorship agreement and has also committed to ensuring NORI pays corporate income tax within Nauru. On March 8, 2008, Tonga and TOML entered into a sponsorship agreement formalizing certain obligations of the parties in relation to TOML’s exploration and potential exploitation of the TOML Area (“TOML Sponsorship Agreement”). Upon reaching the minimum recovery level within the exploitation contract area, TOML has agreed to pay Tonga a seabed mineral recovery payment based on the polymetallic nodules recovered from the exploitation contract area. In addition, TOML has agreed to pay reasonable direct costs incurred by Tonga to administer the obligations of Tonga to the ISA. On September 23, 2021, the Company and Tonga updated the TOML Sponsorship Agreement harmonizing the terms of its engagement with TOML with those held by NORI with Nauru. TOML expects to renegotiate the existing sponsorship agreement with Tonga prior to entering into operations in the TOML area and has committed to paying corporate income tax within Tonga. Contingent Liability On October 28, 2021, a shareholder filed a putative class action against the Company, one of the Company’s executives and a former director in federal district court for the Eastern District of New York, captioned Caper v. TMC The Metals Company Inc. F/K/A Sustainable Opportunities Acquisition Corp., Gerard Barron and Scott Leonard. The complaint alleges that all defendants violated Section 10(b) of the Exchange Act of 1934 and Rule 10b-5 promulgated thereunder, and Messrs. Barron and Leonard violated Section 20(a) of the Exchange Act, by making false and/or misleading statements and/or failing to disclose information about the Company’s operations and prospects during the period from March 4, 2021 and October 5, 2021. On November 15, 2021, a second complaint containing substantially the same allegations was filed, captioned Tran v. TMC the Metals Company, Inc. These cases have been consolidated. On March 6, 2022, a lead plaintiff was selected. An amended complaint was filed on May 12, 2022, reflecting substantially similar allegations, with the Plaintiff seeking to recover compensable damages caused by the alleged wrongdoings. The Company denies any allegations of wrongdoing and filed and served the plaintiff a motion to dismiss on July 12, 2022 and intend to defend against this lawsuit. On July 12, 2023, an oral hearing on the motion to dismiss was held. The parties are currently awaiting a ruling. There is no assurance, however, that the Company or the other defendants will be successful in the Company’s defense of this lawsuit or that insurance will be available or adequate to fund any settlement or judgment or the litigation costs of this action. If the motion to dismiss is unsuccessful, there is a possibility that the Company may incur a loss in this matter. Such losses or range of possible losses cannot be reliably estimated. A resolution of this lawsuit adverse to the Company or the other defendants, however, could have a material effect on the Company’s financial position and results of operations in the period in which the lawsuit is resolved. ​ On January 23, 2023, investors in the 2021 private placement from the Business Combination filed a lawsuit against us in the Commercial Division of New York Supreme Court, New York County, captioned Atalaya Special Purpose Investment Fund II LP et al. v. Sustainable Opportunities Acquisition Corp. n/k/a TMC The Metals Company Inc., Index No. 650449/2023 (N.Y. Sup. Ct.). The Company filed a motion to dismiss on March 31, 2023, after which the plaintiffs filed an amended complaint on June 5, 2023. The amended complaint alleges that the Company breached the representations and warranties in the plaintiffs’ private placement Subscription Agreements and breached the covenant of good faith and fair dealing. The Plaintiffs are seeking to recover compensable damages caused by the alleged wrongdoings. The Company deny any allegations of wrongdoing and filed a motion to dismiss the amended complaint on July 28, 2023. On December 7, 2023, the Court granted our motion to dismiss the claim for breach of the covenant of good faith and fair dealing and denied our motion to dismiss the breach of the Subscription Agreement claim. The Company filed a notice of appeal regarding the Court’s denial of our motion to dismiss the breach of the Subscription Agreement claim. There is no assurance that the Company will be successful in our defense of this lawsuit or that insurance will be available or adequate to fund any settlement or judgment or the litigation costs of this action. Such losses or range of possible losses cannot be reliably estimated.

Segmented Information

Segmented Information	12 Months Ended
	Dec. 31, 2023
Segmented Information
Segmented Information	20. The Company’s business consists of only one operating segment, namely exploration of seafloor polymetallic nodules, which includes the development of a metallurgical process to treat such seafloor polymetallic nodules. Details on the geographical segmentation of the Company’s long-lived assets based on where each legal entity is domiciled are as follows: ​ ​ ​ ​ ​ ​ ​ ​ Equipment December 31, 2023 December 31, 2022 Nauru $ 1,128 $ 1,154 Singapore ​ ​ 1,643 ​ ​ 863 Tonga ​ 5 ​ 7 North America ​ — ​ 1 Total $ 2,776 $ 2,025 ​

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2023
Income Taxes
Income Taxes	21. Reconciliation of Effective Tax Rate The Company is subject to Canadian federal and provincial tax for the estimated assessable profit at a rate of 26.68% for the year ended December 31, 2023 (2022: 26.61%). The Company had no assessable profit in Canada for all periods disclosed. The income tax expense at statutory rates for the Company can be reconciled to the reported loss for the years 2023 and 2022 per the statement of loss and comprehensive loss as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the year ended ​ For the year ended ​ ​ ​ December 31, ​ December 31, ​ ​ 2023 2022 (1) Loss for the year, before taxes ​ $ (73,740) ​ $ (170,887) ​ Canadian Federal and Provincial income tax rates ​ 26.68 % ​ 26.61 % Income tax recovery based on the above rates $ (19,677) $ (45,473) ​ Permanent differences ​ 1,556 ​ 1,926 ​ Effect of differences in future and foreign tax rates ​ 14,038 ​ 36,903 ​ Valuation allowance changes affecting the provision of income taxes ​ 4,124 ​ 6,721 ​ Total income taxes $ 41 $ 77 ​ (1) Comparative amounts for the year ended December 31, 2022 are restated based on actual tax returns filed. The Company currently has no uncertain tax positions and is therefore not reflecting any adjustments. Components of the Company’s deferred income tax assets (liabilities) are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023 December 31, 2022 Deferred Tax Assets ​ ​ Non-capital losses $ 21,195 $ 16,011 Investments ​ 384 ​ 172 Equipment ​ 260 ​ 79 Share issuance costs ​ 496 ​ 218 Total deferred income tax assets $ 22,335 $ 16,480 Valuation allowance ​ (22,335) ​ (16,480) Deferred tax asset recognized $ — $ — ​ ​ ​ ​ ​ ​ ​ Deferred Tax Liability ​ ​ ​ ​ ​ ​ Difference between the book value and the tax basis of the TOML exploration contract (Note 7) ​ $ (10,675) ​ $ (10,675) Deferred tax liability recognized $ (10,675) $ (10,675) (1) Comparative amounts for the year ended December 31, 2022 are restated based on actual tax returns filed. Deductible temporary differences, unused tax losses and unused tax credits are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023 December 31, 2022 Expiry Date Range ​ ​ ​ ​ ​ ​ ​ ​ ​ Non-capital losses $ 89,333 $ 67,409 See below Investments $ 2,856 $ 1,273 Not applicable Equipment $ 962 $ 291 Not applicable Share issuance costs $ 1,860 $ 821 Not applicable ​ As at December 31, 2023, the Company had non-capital loss carry-forwards of $89.3 million that may be used to offset future taxable income. These losses, if not utilized, will expire as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Canada Singapore United States Tonga 2035 $ — $ — $ 2 $ — 2041 ​ 3,741 ​ — ​ — ​ — 2042 ​ ​ 13,707 ​ ​ — ​ ​ 1 ​ ​ — 2043 ​ ​ 12,343 ​ ​ — ​ ​ 3 ​ ​ — No expiry ​ — ​ 20,567 ​ — ​ 38,969 Loss carry-forwards ​ $ 29,791 ​ $ 20,567 ​ $ 6 ​ $ 38,969 ​ The Company files income tax returns in Canada, the United States, Singapore and Tonga, and is subject to examination in these jurisdictions for all years since the Company’s inception in 2011. As at December 31, 2023, all tax years are subject to examination by the tax authorities and no tax authority audits are currently underway. Fiscal years outside the normal statute of limitation remain open to audit by tax authorities due to tax attributes generated in those early years which have been carried forward and may be audited in subsequent years when utilized. The timing of the resolution, settlement and closure of any income tax audits is highly uncertain, and the Company is unable to estimate the full range of possible adjustments to the balance of gross unrecognized tax benefits. It is possible that the balance of gross unrecognized tax benefits could significantly change in the next twelve months. As at December 31, 2023, the 2023 tax year filings for the Company and its subsidiaries (where applicable) remain unfiled and have not been assessed by the relative tax authorities.

Quarterly Financial Data (Unaud

Quarterly Financial Data (Unaudited) Restatement of Previously Issued Financial Statements	12 Months Ended
	Dec. 31, 2023
Quarterly Financial Data (Unaudited) Restatement of Previously Issued Financial Statements
Quarterly Financial Data (Unaudited) Restatement of Previously Issued Financial Statements	22. Quarterly Financial Data (Unaudited) Restatement of Previously Issued Financial Statements The right to royalty payments underlying the NORI asset (sale of future revenue) amounting to $14 million (Note 9) was considered as the transfer (sale) of a non-financial asset in the Company’s previously issued financial statements for the three months ended March 31, 2023, the six months ended June 30, 2023 and the nine months ended September 30, 2023 contained in its Quarterly Reports on Form 10-Q for the quarter ended March 31, 2023, June 30, 2023 and September 30, 2023, respectively, filed with the SEC (the “Previous Financial Statements”). In preparing the Previous Financial Statements, the Company derecognized the capitalized exploration contract related to the NORI project amounting to $0.25 million and recorded the remaining value of the non-financial asset received amounting to $13.75 million as a gain on disposition. In connection with the preparation of the financial statements for the year ended December 31, 2023 and a re-evaluation of ASC 470 by the Company, the Company concluded that the sale of future revenue falls within the scope of ASC 470 and, as a result, the Company re-evaluated whether the offsetting entry to the proceeds it received from Low Carbon Royalties should be classified as debt or deferred income. As the transaction with Low Carbon Royalties was considered an equity investment rather than a sale transaction, the sale of future revenue was reclassified as Royalty Liability, as per ASC 470, in the Company’s 2023 financial statements for the year ended December 31, 2023. Factors that also influenced this reclassification included the Company’s continued significant involvement in generating future cash flows from operations and the fact that the earnings process implied in this transaction had not been completed. As a result, the Company has restated the Previous Financial Statements. - This error had no impact on the consolidated statements of loss and comprehensive loss for the three-month period ended June 30, 2023 and the three month period ended September 30, 2023 - The error and restatement of the 2023 quarterly financial statements does not impact the Company's reported cash position in any of the previously reported periods or as of December 31, 2023. ​ In the following tables, we have presented a reconciliation of our unaudited condensed consolidated financial information as originally reported in the Previous Financial Statements to the as restated amounts as of and for the three months ended March 31, 2023, six months ended June 30, 2023, and nine months ended September 30, 2023. The restatements will be reflected in the comparative financial statements included in our future filings of our 2024 unaudited condensed consolidated financial statements within our Quarterly Reports on Form 10-Q for the quarters ended March 31, 2024, June 30, 2024 and September 30, 2024, respectively. The tables below set forth the unaudited condensed consolidated balance sheet information, the unaudited condensed statements of loss and comprehensive loss and the unaudited condensed consolidated statements of cash flows including the amounts as reported, adjustments and the amounts as restated (in thousands, except per share amounts): ​ Condensed Consolidated Balance Sheet Information ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As at March 31, 2023 ​ As at June 30, 2023 ​ As at September 30, 2023 ​ ​ As Previously Restatement ​ ​ ​ ​ As Previously ​ Restatement ​ ​ ​ ​ As Previously ​ Restatement ​ ​ ​ ​ Reported ​ Adjustments As Restated Reported Adjustments As Restated Reported Adjustments As Restated ASSETS ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Current ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash ​ $ 28,390 ​ $ — ​ ​ 28,390 ​ $ 20,006 ​ $ — ​ ​ 20,006 ​ $ 22,548 ​ ​ — $ 22,548 Receivables and prepayments ​ 3,230 ​ — ​ 3,230 ​ 1,637 ​ — ​ 1,637 ​ 5,325 ​ — ​ 5,325 ​ ​ 31,620 ​ — ​ 31,620 ​ 21,643 ​ — ​ 21,643 ​ 27,873 ​ — ​ 27,873 Non-current ​ ​ ​ ​ ​ ​ ​ ​ ​ Exploration contracts ​ 42,900 ​ 250 ​ 43,150 ​ 42,900 ​ 250 ​ 43,150 ​ 42,900 ​ 250 ​ 43,150 Equipment ​ 1,997 ​ — ​ 1,997 ​ 1,970 ​ — ​ 1,970 ​ 2,078 ​ — ​ 2,078 Right-of-use asset ​ — ​ — ​ — ​ — ​ — ​ — ​ 6,198 ​ — ​ 6,198 Investment ​ 8,781 ​ — ​ 8,781 ​ 8,644 ​ — ​ 8,644 ​ 8,525 ​ — ​ 8,525 ​ ​ 53,678 ​ 250 ​ 53,928 ​ 53,514 ​ 250 ​ 53,764 ​ 59,701 ​ 250 ​ 59,951 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ TOTAL ASSETS ​ $ 85,298 ​ $ 250 ​ $ 85,548 ​ $ 75,157 ​ $ 250 ​ $ 75,407 ​ $ 87,574 ​ $ 250 ​ $ 87,824 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ LIABILITIES ​ ​ ​ ​ ​ ​ ​ ​ ​ Current ​ ​ ​ ​ ​ ​ ​ ​ ​ Accounts payable and accrued liabilities ​ 17,544 ​ — ​ 17,544 ​ 18,113 ​ — ​ 18,113 ​ 19,344 ​ — ​ 19,344 ​ ​ 17,544 ​ — ​ 17,544 ​ 18,113 ​ — ​ 18,113 ​ 19,344 ​ — ​ 19,344 Non-current ​ ​ ​ ​ ​ ​ ​ ​ ​ Deferred tax liability ​ 10,675 ​ — ​ 10,675 ​ 10,675 ​ — ​ 10,675 ​ 10,675 ​ — ​ 10,675 Royalty Liability ​ — ​ 14,000 ​ 14,000 ​ — ​ 14,000 ​ 14,000 ​ — ​ 14,000 ​ 14,000 Warrants liability ​ 1,528 ​ — ​ 1,528 ​ 2,314 ​ — ​ 2,314 ​ 2,197 ​ — ​ 2,197 TOTAL LIABILITIES ​ $ 29,747 ​ $ 14,000 ​ $ 43,747 ​ $ 31,102 ​ $ 14,000 ​ $ 45,102 ​ $ 32,216 ​ $ 14,000 ​ $ 46,216 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ EQUITY ​ ​ ​ ​ ​ ​ ​ ​ ​ Common shares (unlimited shares, no par value) ​ 345,090 ​ — ​ 345,090 ​ 345,775 ​ — ​ 345,775 ​ 434,099 ​ — ​ 434,099 Special Shares ​ — ​ — ​ — ​ — ​ — ​ — ​ — ​ — ​ — Additional paid in capital ​ 186,796 ​ — ​ 186,796 ​ 188,722 ​ — ​ 188,722 ​ 124,168 ​ — ​ 124,168 Accumulated other comprehensive loss ​ (1,216) ​ — ​ (1,216) ​ (1,216) ​ — ​ (1,216) ​ (1,216) ​ — ​ (1,216) Deficit ​ (475,119) ​ (13,750) ​ (488,869) ​ (489,226) ​ (13,750) ​ (502,976) ​ (501,693) ​ (13,750) ​ (515,443) TOTAL EQUITY ​ $ 55,551 ​ (13,750) ​ $ 41,801 ​ $ 44,055 ​ (13,750) ​ $ 30,305 ​ $ 55,358 ​ ​ (13,750) ​ $ 41,608 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ TOTAL LIABILITIES AND EQUITY ​ $ 85,298 ​ $ 250 ​ $ 85,548 ​ $ 75,157 ​ $ 250 ​ $ 75,407 ​ $ 87,574 ​ $ 250 ​ $ 87,824 ​ ​ Condensed Consolidated Statements of Loss and Comprehensive Loss ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For three months period ended ​ For six months period ended ​ For nine months period ended ​ ​ March 31, 2023 ​ June 30, 2023 ​ September 30, 2023 ​ ​ As Previously ​ Restatement ​ ​ ​ ​ As Previously ​ Restatement ​ ​ ​ ​ As Previously ​ Restatement ​ ​ ​ ​ Reported Adjustments As Restated Reported Adjustments As Restated Reported Adjustments As Restated Operating expenses ​ ​ ​ ​ ​ ​ ​ ​ ​ Exploration and evaluation expenses ​ $ 7,169 ​ — ​ $ 7,169 ​ $ 15,267 ​ — ​ $ 15,267 ​ $ 23,172 ​ — ​ $ 23,172 General and administrative expenses ​ 6,214 ​ — ​ 6,214 ​ 11,345 ​ — ​ 11,345 ​ 15,958 ​ — ​ 15,958 Operating loss ​ 13,383 ​ — ​ 13,383 ​ 26,612 ​ — ​ 26,612 ​ 39,130 ​ — ​ 39,130 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Other items ​ ​ ​ ​ ​ ​ ​ ​ ​ Equity-accounted investment loss ​ 219 ​ — ​ 219 ​ 356 ​ — ​ 356 ​ 475 ​ — ​ 475 Gain on disposition of asset ​ (13,750) ​ 13,750 ​ — ​ (13,750) ​ 13,750 ​ — ​ (13,750) ​ 13,750 ​ — Change in fair value of warrants liability ​ 544 ​ — ​ 544 ​ 1,331 ​ — ​ 1,331 ​ 1,214 ​ — ​ 1,214 Foreign exchange loss ​ 29 ​ — ​ 29 ​ 52 ​ — ​ 52 ​ 66 ​ — ​ 66 Interest income ​ (454) ​ — ​ (454) ​ (773) ​ — ​ (773) ​ (1,092) ​ — ​ (1,092) Fees and interest on credit facility ​ 27 ​ — ​ 27 ​ 277 ​ — ​ 277 ​ 529 ​ — ​ 529 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loss and comprehensive loss for the year, before tax ​ $ (2) ​ $ 13,750 ​ $ 13,748 ​ $ 14,105 ​ $ 13,750 ​ $ 27,855 ​ $ 26,572 ​ $ 13,750 ​ $ 40,322 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Tax expense ​ — ​ — ​ — ​ — ​ — ​ — ​ — ​ — ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loss (gain) and comprehensive loss (gain) for the period, after tax ​ $ (2) ​ $ 13,750 ​ $ 13,748 ​ $ 14,105 ​ $ 13,750 ​ $ 27,855 ​ $ 26,572 ​ $ 13,750 ​ $ 40,322 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loss per share ​ ​ ​ ​ ​ ​ ​ ​ ​ - basic and diluted ​ — ​ $ 0.05 ​ $ 0.05 ​ $ 0.05 ​ $ 0.05 ​ $ 0.10 ​ $ 0.09 ​ $ 0.05 ​ $ 0.14 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average number of Common Shares outstanding – basic ​ 272,029,603 ​ 272,029,603 ​ 272,029,603 ​ 276,702,050 ​ 276,702,050 ​ 276,702,050 ​ 282,745,892 ​ 282,745,892 ​ 282,745,892 Weighted average number of Common Shares outstanding – diluted ​ 300,376,133 ​ 272,029,603 ​ 272,029,603 ​ 276,702,050 ​ 276,702,050 ​ 276,702,050 ​ 282,745,892 ​ 282,745,892 ​ 282,745,892 ​ ​ Condensed Consolidated Statements of Cash Flows ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For three months period ended ​ For six months period ended ​ For nine months period ended ​ ​ March 31, 2023 ​ June 30, 2023 ​ September 30, 2023 ​ ​ As Previously ​ Restatement ​ ​ ​ As Previously ​ Restatement ​ ​ ​ As Previously ​ Restatement ​ ​ ​ Reported Adjustments As Restated Reported Adjustments As Restated Reported Adjustments As Restated Operating activities Gain/(Loss) for the period 2 (13,750) (13,748) (14,105) (13,750) (27,855) (26,572) (13,750) (40,322) Items not affecting cash: Amortization 88 — 88 175 — 175 262 — 262 Lease expense — — — — — — 318.00 — 318.00 Expenses settled with share-based payments 1,775 — 1,775 4,307 — 4,307 6,839 — 6,839 Expenses to be settled with share-based payments 15 — 15 — — — — — — Equity-accounted investment loss 219 — 219 356 — 356 475 — 475 Gain on disposition of asset (13,750) 13,750 — (13,750) 13,750 — (13,750) 13,750 — Change in fair value of warrants liability 545 — 545 1,331 — 1,331 1,214 — 1,214 Vesting of Allseas Warrant — — — — — — — — — Unrealized foreign exchange movement (20) — (20) (17) — (17) (24) — (24) Changes in working capital: — — — — — — — Receivables and prepayments (469) — (469) 1,123 — 1,123 (2,364) — (2,364) Accounts payable and accrued liabilities (11,877) — (11,877) (11,277) — (11,277) (10,757) — (10,757) Net cash used in operating activities (23,472) — (23,472) (31,857) — (31,857) (44,359) — (44,359) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Investing activities Cash received from investment in Low Carbon Royalties 5,000 (5,000) — 5,000 (5,000) — 5,000 (5,000) — Acquisition of equipment — — — (75) — (75) (175) (175) Net cash provided by (used in) investing activities 5,000 (5,000) — 4,925 (5,000) (75) 4,825 (5,000) (175) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Financing activities Proceeds from Low Carbon Royalties investment — 5,000 5,000 — 5,000 5,000 — 5,000 5,000 Proceeds from Registered Direct Offering — — — — — — 15,723 — 15,723 Expenses paid for Registered Direct Offering — — — — — — (779) — (779) Proceeds from PIPE financing — — — — — — — — — Expenses paid for PIPE financing — — — — — — — — — Proceeds from employee stock plan — — — 49 — 49 49 — 49 Proceeds from exercise of stock options — — — — — — 77 — 77 Proceeds from exercise of warrants by Allseas — — — — — — 116 — 116 Proceeds from issuance of shares — — — 30 — 30 30 — 30 Taxes withheld and paid on share-based compensation — — — — — — — — Net cash provided by financing activities — 5,000 5,000 79 5,000 5,079 15,216 5,000 20,216 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Decrease in cash (18,472) — (18,472) (26,853) — (26,853) (24,318) — (24,318) Impact of exchange rate changes on cash 20 — 20 17 — 17 24 — 24 Cash - beginning of period 46,842 — 46,842 46,842 — 46,842 46,842 — 46,842 Cash - end of period 28,390 — 28,390 20,006 — 20,006 22,548 — 22,548 ​

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2023
Subsequent Events
Subsequent Events	23. Amendment to Credit Facility with Allseas Affiliate On March 22, 2024, the Company entered into the Second Amendment to the Unsecured Credit Facility with the Lender, the parent of Allseas Investments S.A. and an affiliate of Allseas, to extend the Credit Facility to August 31, 2025 and to provide that the underutilization fee thereunder shall cease to be payable after the date on which the Company or the Lender gives notice of termination of the agreement. Under the amended Credit Facility, the Company may borrow from the Lender up to $25,000,000 in the aggregate through August 31, 2025. Credit Facility with ERAS Capital LLC and Gerard Barron On March 22, 2024, the Company entered into an Unsecured Credit Facility (the “2024 Credit Facility”) with Gerard Barron, our Chief Executive Officer and Chairman, and ERAS Capital LLC, the family fund of our director, Andrei Karkar (collectively, the “2024 Lenders”), pursuant to which, the Company may borrow from the 2024 Lenders up to $20,000,000 in the aggregate ($10,000,000 from each of the 2024

Significant Accounting Polici_2

Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2023
Significant Accounting Policies Adopted During the Period
Foreign Currencies	i. Foreign Currencies The functional currency is the currency of the primary economic environment in which the entity operates. The functional currency of the Company and all its subsidiaries is the U.S. Dollar, except for NEAT and NHEF, whose functional currency is the Australian Dollar. At the end of each reporting period, monetary assets and liabilities that are denominated in foreign currencies are translated into the functional currency at the rates prevailing at that date. Non-monetary assets and liabilities carried at fair value that are denominated in currencies other than the U.S. Dollar are translated at rates prevailing at the date when the fair value was determined. All gains and losses on translation of these foreign currency transactions are included in the statements of loss and comprehensive loss. Non-monetary items that are measured at historical cost in a foreign currency are not retranslated. For consolidation purposes, the assets and liabilities of entities with functional currencies other than the US Dollar are translated at the period end rates of exchange, and the results of their operations are translated at average rates of exchange for the period. The resulting changes are recognized in accumulated other comprehensive loss within equity as currency translation differences.
Use of Estimates	ii. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts in the consolidated financial statements and the notes thereto. Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, the evaluation of going concern, the valuation of share-based payments, including valuation of incentive stock options (Note 15), as well as the valuation of warrants liability (Note 13), and the valuation of the investment in Low Carbon Royalties Inc. (“Low Carbon Royalties”) (Note 9). Actual results could differ materially from those estimates.
Loss Per Share	iii. Loss Per Share Basic loss per share is computed by dividing loss available to common shareholders by the weighted average number of common shares outstanding during the year. The computation of diluted loss per share assumes the conversion, exercise or contingent issuance of securities only when such conversion, exercise or issuance would have a dilutive effect on the loss per share. The dilutive effect of convertible securities is reflected in the diluted loss per share by application of the “if converted” method. The dilutive effect of outstanding options and their equivalents is reflected in the diluted loss per share by application of the treasury stock method.
Financial Instruments	iv. Financial Instruments Financial assets and liabilities are recognized when the Company becomes a party to the contractual provisions of the instrument. Financial assets are derecognized when the rights to receive cash flows from the assets have expired, or have been transferred, and the Company has transferred substantially all risks and rewards of ownership. A financial liability is derecognized when the obligation specified in the contract is discharged, cancelled, or expires. The Company’s financial instruments consists of cash and cash equivalents, receivables, accounts payable and accrued liabilities, and deferred acquisition costs which are recorded at amortized cost as well as warrants to acquire common shares of the Company which are measured at fair value.
Fair Value of Financial Instruments	v. Fair Value of Financial Instruments Fair value estimates of financial instruments are made at a specific point in time, based on relevant information about financial markets and specific financial instruments. As these estimates are subjective in nature, involving uncertainties and matters of significant judgment, they cannot be determined with precision. Changes in assumptions can significantly affect estimated fair value. The Company measures fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the reporting date. In accordance with U.S. GAAP, the Company utilizes a three-tier hierarchy, which prioritizes the inputs used in the valuation methodologies in measuring fair value: ● Level 1  - Valuations based on quoted prices in active markets for identical assets or liabilities that an entity has the ability to access. ● Level 2  - Valuations based on quoted prices for similar assets or liabilities, quoted prices for identical assets or liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable data for substantially the full term of the assets or liabilities. ● Level 3  - Valuations based on inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. In some circumstances, the inputs used to measure fair value might be categorized within different levels of the fair value hierarchy. In those instances, the fair value measurement is categorized in its entirety in the fair value hierarchy based on the lowest level input that is significant to the fair value measurement. There were no transfers between fair value measurement levels during the years ended December 31, 2023 and 2022. As at December 31, 2023 and 2022, the carrying values of cash, receivables, accounts payable and accrued liabilities approximate their fair values due to the short-term nature of these instruments. The financial instruments also include warrants which are valued at fair value as disclosed in Note 13.
Cash and Cash Equivalents	vi. Cash and Cash Equivalents Cash include cash on hand and term deposits with a remaining term to maturity at acquisition of three months or less. As at December 31, 2023 and 2022, the Company had no cash equivalents.
Equipment	vii. Equipment Equipment are stated at cost less accumulated depreciation and accumulated impairment losses. Cost includes expenditures that are directly attributable to the acquisition of the asset. Subsequent costs are included in the asset’s carrying amount or recognized as a separate asset, as appropriate, when it is probable that future economic benefits from such assets will flow to the Company and the cost of such assets can be measured reliably. The carrying amount of an asset is derecognized when it is replaced or taken out of service. Repairs and maintenance costs are charged to the statement of loss and comprehensive loss during the period they are incurred. The major categories of equipment are amortized on a declining balance basis as follows: ​ ​ ​ ​ ​ Exploration and other equipment 30 % Office equipment 30 % ​ The Company allocates the amount initially recognized to each asset’s significant components and depreciates each component separately. Amortization methods and useful life of the assets are reviewed at each financial period end and adjusted on a prospective basis, if required. Gains and losses on disposals of equipment are determined by comparing the proceeds with the carrying amount of the asset and are included in the statement of loss and comprehensive loss.
Exploration Contracts	viii. Exploration Contracts The Company is in the exploration stage with respect to its investment in exploration contracts and follows the practice of capitalizing costs related to the acquisition of such exploration contracts. The cost of exploration contracts will be charged to operations using a unit-of-production method based on proven and probable reserves once commercial production commences in the future.
Exploration and Evaluation Expenses	ix. Exploration and Evaluation Expenses While in the exploration phase, the Company expenses all costs related to exploration and development of exploration contracts. Such exploration and development costs include, but are not limited to, exploration contract management, geological, geochemical and geophysical studies, environmental studies and process development.
Share-Based Compensation	x. Share-Based Compensation Share-based compensation is measured at the grant date based on the fair value of the award and is recognized over the requisite service period. Share-based compensation costs are charged to exploration and evaluation expenses or general and administrative expenses in the statement of loss and comprehensive loss. The Company recognizes forfeiture of any awards as they occur. The Company records share-based compensation from the issuance of stock options and restricted share units (“RSUs”) to employees with service-based conditions using the accelerated attribution method. For stock options and restricted share units issued with performance conditions (Note 15), the Company recognizes share-based compensation cost when the specific performance targets become probable of being achieved using the accelerated attribution method. When these costs relate to equity financing, they are netted against share capital as a share issuance cost. The fair value of stock option awards with only service and/or performance conditions is estimated on the grant date using a Black-Scholes option-pricing model. For stock options issued with market conditions (Note 15), the Company recognizes share-based compensation cost over the expected achievement period for the related market capitalization milestone determined on the grant date. If the related market capitalization milestone is achieved earlier than its expected achievement period, then any unamortized share-based compensation cost for that milestone is recognized at that time. The fair value of market-based stock option awards is estimated on the grant date using Monte-Carlo simulations. The Company at times grants common shares, stock options or RSUs in lieu of cash to certain vendors for their services to the Company. The Company recognizes the associated cost in the same period and manner as if the Company paid cash for the services provided.
Warrants Liability	xi. Warrants Liability The Company evaluates all of its financial instruments, including issued share purchase warrants, to determine if such instruments are derivatives or contain features that qualify as embedded derivatives, pursuant to U.S. GAAP Accounting Standard Coding (“ASC”) 480, Distinguishing Liability from Equity (“ASC 480”), and ASC 815, Derivatives and Hedging (“ASC 815”). The classification of derivative instruments, including whether such instruments should be recorded as liabilities or as equity, is re-assessed at the end of each reporting period. The Company accounts for the Public Warrants and Private Warrants (as defined below) in accordance with the guidance contained in ASC 815 (Subtopic 40), Derivative and Hedging – Contracts in Entity’s Own Equity (“ASC 815-40”), and the U.S. Securities and Exchange Commission (“SEC”) Division of Corporation Finance’s April 12, 2021 Public Statement, Staff Statement on Accounting and Reporting Considerations for Warrants Issued by Special Purpose Acquisition Companies (“SEC Statement”), under which the 15,000,000 common share warrants issued by SOAC as part of the units offered in its initial public offering (“Public Warrants”) were determined to meet the criteria for equity classification, while the 9,500,000 private placement common share warrants issued by SOAC in a private placement simultaneously with the closing of the initial public offering (“Private Warrants”) did not meet the criteria for equity classification and were recorded as liabilities. Specifically, the terms of the Private Warrants provide for potential changes to the settlement amounts dependent upon the characteristics of the warrant holder, and, because the holder of a Private Warrant is not an input into the pricing of a fixed-for-fixed option on equity shares, such provision would preclude the Private Warrants from being classified in equity and should be classified as a liability. Accordingly, the Company classified the Private Warrants as liabilities measured at fair value and adjusts the Private Warrants to their fair value at the end of each reporting period. Fair value changes in the Private Warrants are recognized in the Company’s statement of loss and comprehensive loss. The Company granted warrants to Allseas on March 4, 2021 to acquire 11.6 million TMC common shares at a nominal value (the “Allseas Warrant”). The Allseas Warrant vested and became exercisable upon successful completion of the PMTS in the fourth quarter of 2022, and had been accounted for as equity, since the warrants do not meet the criteria to be classified as liability as defined in ASC Topic 480, Distinguishing Liabilities from Equity. The Company issued Class A Warrants under the Registered Direct Offering (Note 12) in the third quarter of 2023. The Class A Warrants issued met the criteria for equity classification and were recorded under additional paid in capital (Note 13).
Income Taxes	xii. Income Taxes Income tax expense represents the sum of current tax expense and deferred tax expense. Current tax expense is based on taxable profit for the year and includes any adjustments to tax payable in respect of previous years. Taxable profit differs from accounting profit or loss as reported in the consolidated income statement because it excludes (i) items of income or expense that are taxable or deductible in other years and (ii) items that are never taxable or deductible. The Company’s liability for current tax is calculated using tax rates that have been enacted by the balance sheet date. The Company’s policy is to account for income tax related interest and penalties in income tax expense in the accompanying statements of loss and comprehensive loss. Deferred tax income taxes are accounted for using the asset and liability method. Deferred income tax assets and liabilities are based on temporary differences, which are differences between the accounting basis and tax basis of assets and liabilities, non-capital loss, capital loss, and tax credits carryforwards and are measured using the enacted tax rates and laws expected to apply when these differences reverse. Deferred tax benefits, including non-capital loss, capital loss, and tax credit carryforwards are recognized to the extent that realization of such benefits is considered more likely than not. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in the consolidated income statement in the period that enactment occurs. When realization of deferred income tax assets does not meet the more likely than not criterion for recognition, a valuation allowance is provided.
Leases	i. Leases The Company records leases in accordance with ASC 842, Leases Lease liabilities are recognized on the commencement date of the lease based on the present value of the future lease payments over the lease term. The discount rate used to calculate the present value of lease payments is the rate implicit in the lease. Lease liabilities due within the subsequent 12 months of the reporting date are classified as current lease liabilities and are included in accounts payable and accrued liabilities on the Company’s condensed consolidated balance sheet. Lease liabilities payable after the subsequent 12 months of the reporting date are classified as non-current lease liabilities and are presented as non-current lease liability in the condensed consolidated balance sheet. ROU assets are valued at the initial measurement of the lease liability, plus any indirect costs or rent prepayments, and reduced by any lease incentives and any deferred lease payments. ROU assets are recorded as Right-of-use assets, net of any amortization on the condensed consolidated balance sheet. Operating ROU assets are amortized on a straight-line basis over the lease term, whereas Finance ROU assets are amortized on a front-loaded basis. Depending on the nature of the ROU asset, the amortization expense is either included in exploration and evaluation expenses or in general and administrative expenses. The Company subsequently measures the ROU assets for an operating lease at the amount of the remeasured lease liability (i.e. the present value of the remaining lease payments), adjusted for the remaining balance of any lease incentives received, any cumulative prepaid or accrued rent if the lease payments are uneven throughout the lease term and any unamortized initial direct costs. The ROU assets for a finance lease are subsequently measured by amortizing them on a straight-line basis over the shorter of the lease term or useful life and also adjustment for any impairments. In the third quarter of 2023, the Company entered into an Exclusive Vessel Use Agreement with Allseas (Note 8) which was recognized as a lease agreement in accordance with accounting standards.
Investments	ii. Investments The Company consolidates investments over which it has control in accordance with ASC 810, Consolidation Investments-Equity Method and Joint Ventures The Company and its wholly-owned subsidiary, NORI, entered into an investment with Low Carbon Royalties on February 21, 2023 (Note 9).
Evaluation of Going Concern	i. Evaluation of Going Concern The Company evaluates its ability to operate as a going concern at each reporting period. This evaluation requires the Company to estimate its cash flow commitments over a forecast period of twelve months and whether it has the financial ability to pay for such commitments. Changes in these estimates and assumptions may have a material impact on this assessment.
Valuation of Share-Based Payments	ii. Valuation of Share-Based Payments The fair market value of share-based awards granted to employees, non-employees and directors is based on the closing market price of the Company’s shares, on the date these were granted (Note 15). This valuation approach involves the use of estimates, judgments and assumptions that are subjective, such as those regarding the probability of future events. Changes in these estimates and assumptions impact the Company’s valuation as of the valuation date and may have a material impact on the valuation of the Company’s common shares. Changes in these assumptions used to determine the fair value of incentive stock options, including the vesting timeline of granted stock options, could have a material impact on the Company’s loss and comprehensive loss.
Valuation of Warrants Liability	iii. Valuation of Warrants Liability The Company re-measures the fair value of the Private Warrants at the end of each reporting period (Note 13). The fair value of the Private Warrants was estimated using a Black-Scholes option pricing model whereby the expected volatility was estimated using a binomial model based on consideration of the implied volatility from the Company’s Public Warrants adjusted to account for the call feature of the Public Warrants at prices above $18.00 during 20 trading days within any 30-trading-day period. During the year the Company issued Class A warrants as a part of the Registered Direct Offering (Note 12 & Note 13). The warrants were valued using a Monte Carlo simulation by running 250,000 trials. The model assumed that the Company’s share price follows geometric Brownian motion which is a standard assumption used in Monte Carlo univariate pricing models. The valuation was calculated under a risk-neutral framework using a zero-coupon risk-free interest rate derived from the Treasury Constant Maturities yield curve for a term until the expiry of the Warrants. The Company’s share price was simulated up to the expiration date using a blended volatility, calculated by assigning equal weights to both implied volatility of the Company’s Public Warrants and the historical volatility of the Company’s share price.
Valuation of Royalty Liability	iv. Valuation of Royalty Liability The Company re-measures the fair value of its royalty liability at each reporting date. As NORI is in an advanced exploration stage and pre-production, the fair value of the royalty liability is measured by using a market approach which entails examining recent royalty transactions prior to the reporting date, focusing on those transactions that involve similar metals as contained in NORI’s polymetallic nodules. The Company compares the specific characteristics of these transactions to estimate the fair value of its royalty liability at the reporting date.

Basis of Presentation (Tables)

Basis of Presentation (Tables)	12 Months Ended
	Dec. 31, 2023
Basis of Presentation
Summary of principal subsidiaries of the Company, their activities, and their geographic locations	These consolidated financial statements include the financial statements of the Company and its subsidiaries. The principal subsidiaries of the Company, their activities, and their geographic locations as at December 31, 2023 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Proportion of ​ ​ ​ ​ ​ ​ Interest Held Subsidiary ​ Principal Activity ​ Location ​ by the Company DeepGreen Engineering Pte. Ltd. Mineral exploration Singapore 100% DeepGreen Metals ULC Mineral exploration Canada 100% DeepGreen Resources, LLC Holding Company USA 100% DeepGreen TOML Holding 1 Ltd. Holding Company British Virgin Islands 100% DeepGreen TOML Holding 2 Ltd. Holding Company British Virgin Islands 100% DeepGreen TOML Singapore Pte. Ltd. Mineral exploration Singapore 100% Koloa Moana Resources Ltd. Holding Company Canada 100% Nauru Education and Training Foundation Inc. (“NEAT”) Holding Company Republic of Nauru 100% Nauru Health and Environment Foundation Inc. (“NHEF”) Holding Company Republic of Nauru 100% Nauru Ocean Resources Inc. Mineral exploration Republic of Nauru 100% Offshore Minerals Pty. Ltd. Mineral exploration Australia 100% The Metals Company Australia Pty Ltd Holding Company Australia 100% TMC The Metals Company UK Limited Holding Company United Kingdom 100% Tonga Offshore Mining Ltd. Mineral exploration Kingdom of Tonga 100%

Significant Accounting Polici_3

Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2023
Significant Accounting Policies Adopted During the Period
Summary of major categories of equipment are amortized on a declining balance	​ ​ ​ ​ ​ Exploration and other equipment 30 % Office equipment 30 %

Receivables and Prepayments (Ta

Receivables and Prepayments (Tables)	12 Months Ended
	Dec. 31, 2023
Receivables And Prepayments.
Schedule of receivables and prepayments	​ ​ ​ ​ ​ ​ ​ ​ ​ December 31 2023 December 31 2022 Taxes and other receivables $ 467 $ 117 Prepayments ​ 1,511 ​ 2,609 ​ $ 1,978 $ 2,726 ​

Equipment (Tables)

Equipment (Tables)	12 Months Ended
	Dec. 31, 2023
Equipment.
Schedule of equipment	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Exploration and ​ ​ ​ ​ Cost ​ other equipment ​ Office equipment ​ Total December 31, 2021 $ 2,800 ​ $ 21 ​ $ 2,821 Additions ​ 1,026 ​ — ​ 1,026 December 31, 2022 $ 3,826 ​ $ 21 ​ $ 3,847 Additions ​ 1,111 ​ — ​ 1,111 December 31, 2023 $ 4,937 ​ $ 21 ​ $ 4,958 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Accumulated depreciation ​ ​ ​ December 31, 2021 $ (1,386) ​ $ (19) ​ $ (1,405) Amortization for the year ​ (416) ​ (1) ​ (417) December 31, 2022 $ (1,802) ​ $ (20) ​ $ (1,822) Amortization for the year ​ (359) ​ (1) ​ (360) December 31, 2023 $ (2,161) ​ $ (21) ​ $ (2,182) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net book value ​ ​ ​ ​ ​ ​ As at December 31, 2022 $ 2,024 ​ $ 1 ​ $ 2,025 As at December 31, 2023 $ 2,776 ​ $ — ​ $ 2,776 ​

Strategic Alliance with Allse_2

Strategic Alliance with Allseas and Affiliates (Table)	12 Months Ended
	Dec. 31, 2023
Strategic Partnerships
Net amount of lease liability and right-of-use asset	As at December 31, 2023, the net amount of the lease liability ​ ​ ​ ​ ​ ​ Lease Liability Balance as at August 1, 2023 ​ $ 6,515 Payments made during the year by issuing 4.15 million common shares ​ 6,515 Balance as at December 31, 2023 ​ $ — ​ ​ ​ ​ ​ ​ Right-of-use Asset Balance as on August 1, 2023 ​ $ 6,515 Lease expense during the year ​ 794 Balance as at December 31, 2023 ​ $ 5,721

Investment in Low Carbon Roya_2

Investment in Low Carbon Royalties (Tables)	12 Months Ended
	Dec. 31, 2023
Strategic Partnerships
Schedule of investment	​ ​ ​ ​ ​ ​ Investment Fair value of NORI Royalty ​ $ 14,000 Cash received ​ $ (5,000) Cost of Investment on Closing Date ​ $ 9,000 Equity-accounted investment loss for the year ​ (571) Investment as at December 31, 2023 ​ $ 8,429
Schedule of low carbon royalties	​ ​ ​ ​ ​ ​ December 31 For the year ended ​ 2023 Current Assets ​ $ 1,091 Non-Current Assets ​ ​ 26,315 Current Liabilities ​ ​ 131 ​ ​ ​ ​ Royalty Income ​ $ 399 Total Revenue ​ 480 Comprehensive Income (Loss) for the year ​ $ (1,747) ​

Exploration Contracts (Tables)

Exploration Contracts (Tables)	12 Months Ended
	Dec. 31, 2023
Exploration Contracts.
Schedule of reconciliation of the Company's capitalized exploration	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Marawa ​ ​ ​ ​ ​ ​ NORI ​ Option ​ TOML ​ ​ ​ ​ ​ Contract ​ Agreement ​ Contract ​ Total December 31, 2022 $ 250 ​ $ 199 ​ $ 42,701 ​ $ 43,150 December 31, 2023 $ 250 ​ $ 199 ​ $ 42,701 ​ $ 43,150
Schedule of exploration and evaluation expenses	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ NORI Marawa TOML ​ ​ ​ ​ Exploration ​ Option ​ Exploration ​ ​ ​ For the year ended December 31, 2023 ​ Contract ​ Agreement ​ Contract ​ Total Environmental Studies ​ $ 16,421 ​ $ — ​ $ — ​ $ 16,421 Exploration Labor ​ ​ 7,268 ​ ​ 227 ​ ​ 711 ​ ​ 8,206 Share-Based Compensation (Note 15) ​ 4,444 ​ 146 ​ 443 ​ 5,033 Mining, Technological and Process Development ​ ​ 13,694 ​ ​ — ​ ​ 1,262 ​ ​ 14,956 Prefeasibility Studies ​ ​ 1,345 ​ ​ — ​ ​ — ​ ​ 1,345 Sponsorship, Training and Stakeholder Engagement (1) ​ ​ 2,248 ​ ​ 202 ​ ​ 996 ​ ​ 3,446 Other ​ 433 ​ — ​ 9 ​ 442 ​ ​ $ 45,853 ​ $ 575 ​ $ 3,421 ​ $ 49,849 (1) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ NORI Marawa TOML ​ ​ ​ ​ Exploration ​ Option ​ Exploration ​ ​ ​ For the year ended December 31, 2022 ​ Contract ​ Agreement ​ Contract ​ Total Environmental Studies ​ $ 38,022 ​ $ — ​ $ — ​ $ 38,022 Exploration Labor ​ ​ 4,420 ​ ​ 758 ​ ​ 842 ​ ​ 6,020 Share-Based Compensation (Note 15) ​ 6,086 ​ 1,167 ​ 1,235 ​ 8,488 Mining, Technological and Process Development ​ ​ 1,823 ​ ​ 47 ​ ​ 118 ​ ​ 1,988 PMTS ​ ​ 15,603 ​ ​ 670 ​ ​ 1,546 ​ ​ 17,819 Allseas Warrant (Note 13) ​ 62,910 ​ — ​ 6,990 ​ 69,900 Sponsorship, Training and Stakeholder Engagement ​ ​ 891 ​ ​ 194 ​ ​ 476 ​ ​ 1,561 Other ​ ​ 706 ​ ​ 16 ​ ​ 79 ​ ​ 801 ​ ​ $ 130,461 ​ $ 2,852 ​ $ 11,286 ​ $ 144,599 ​

General and Administrative Ex_2

General and Administrative Expenses (Tables)	12 Months Ended
	Dec. 31, 2023
General and Administrative Expenses
Schedule of General and Administrative Expenses	​ ​ ​ ​ ​ ​ ​ ​ ​ For the year ended For the year ended ​ ​ December 31, ​ December 31, ​ ​ 2023 ​ 2022 Professional and consulting fees (1) ​ $ 6,584 ​ $ 6,795 Investor relations (2) ​ 1,547 ​ 1,514 Office and sundry ​ 3,503 ​ 4,926 Salaries and wages ​ 4,995 ​ 5,921 Director fees ​ 774 ​ 788 Share-based compensation ​ 4,122 ​ 8,596 Transfer agent and filing fees ​ 363 ​ 378 Travel expenses ​ 609 ​ 600 Other expenses ​ 43 ​ — General and Administrative Expenses ​ $ 22,540 ​ $ 29,518 (1) (2)

Warrants (Tables)

Warrants (Tables)	12 Months Ended
	Dec. 31, 2023
Class of Warrant or Right
Schedule of changes in the fair value of warrant liabilities	​ ​ ​ ​ ​ ​ Private ​ ​ Warrants Warrants liability as at December 31, 2022 ​ $ 983 Increase in fair value of warrants liability ​ 986 Warrants liability as at December 31, 2023 ​ $ 1,969
Private Warrants
Class of Warrant or Right
Schedule of fair value measurement input	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023 December 31, 2022 ​ Exercise price ​ $ 11.50 ​ $ 11.50 ​ Share price ​ $ 1.10 ​ $ 0.77 ​ Volatility (1) ​ 105.34 % ​ 88.05 % Term ​ 2.69 years ​ 3.69 years Risk-free rate ​ 3.98 % ​ 4.04 % Dividend yield ​ 0.0 % ​ 0.0 % 1. The Company used a blended volatility approach to calculate the fair value of the warrants on December 31, 2023 by assigning equal weights to both implied volatility of the Company’s Public Warrants and the historical volatility of the share price. The volatility used in calculating the fair value of the warrants as at December 31, 2022 comprised only of the implied volatility of the Company’s Public Warrants.
Class A Warrants
Class of Warrant or Right
Schedule of fair value measurement input	​ ​ ​ ​ ​ ​ ​ August 14, ​ ​ 2023 ​ Exercise price ​ $ 3.00 ​ Share price ​ $ 1.41 ​ Call price threshold ​ $ 6.50 ​ Volatility ​ 107.08 % Term (years) ​ 4.38 ​ Risk-free rate ​ 4.32 % Dividend yield ​ 0.0 %

Common Shares (Tables)

Common Shares (Tables)	12 Months Ended
	Dec. 31, 2023
Common Shares
Schedule of authorized and issued & outstanding common shares and special shares	As at December 31, 2023, the authorized, issued and outstanding common shares and Special Shares of the Company are as follows: ​ ​ ​ ​ ​ ​ ​ Issued and ​ ​ Authorized ​ Outstanding Common shares Unlimited, with no par value 306,558,710 Class A Special Shares 5,000,000, with no par value 4,448,259 Class B Special Shares 10,000,000, with no par value 8,896,399 Class C Special Shares 10,000,000, with no par value 8,896,399 Class D Special Shares 20,000,000, with no par value 17,792,922 Class E Special Shares 20,000,000, with no par value 17,792,922 Class F Special Shares 20,000,000, with no par value 17,792,922 Class G Special Shares 25,000,000, with no par value 22,241,179 Class H Special Shares 25,000,000, with no par value 22,241,179 Class I Special Shares 500,000, with no par value 500,000 Class J Special Shares 741,000, with no par value 741,000
Summary of the Special Shares and their respective vesting thresholds, assuming the full amount of Special Shares from Rollover Options are issued	​ Special Share Class A B C D E F G H I J Share Trigger price ($) 15 25 35 50 75 100 150 200 50 12 Special Shares (million) 5 10 10 20 20 20 25 25 0.5 0.7
Schedule of common shares	​ ​ ​ ​ ​ ​ ​ Common shares Number Amount December 31, 2021 225,432,493 ​ $ 296,051 Issuance of shares under PIPE financing (Note 12) 38,266,180 ​ ​ 29,621 Exercise of stock options (Note 15) 118,461 ​ ​ 142 Conversion of restricted share units ​ 2,877,068 ​ ​ 6,875 Share purchase under Employee Stock Purchase Plan (Note 15) 117,929 ​ ​ 193 December 31, 2022 266,812,131 ​ $ 332,882 Issuance of shares under Registered Direct Offering (Note 12) 7,961,540 ​ ​ 11,420 Exercise of warrant by Allseas (Note 13) ​ 11,578,620 ​ ​ 70,016 Shares issued to Allseas (Notes 8) ​ 15,000,000 ​ ​ 15,910 Exercise of stock options (Note 15) ​ 120,000 ​ ​ 144 Conversion of restricted share units (Note 15) ​ 4,912,747 ​ ​ 7,720 Share purchase under Employee Stock Purchase Plan (Note 15) ​ 173,672 ​ ​ 147 December 31, 2023 306,558,710 ​ $ 438,239 ​

Share-Based Compensation (Table

Share-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2023
Stock Options (Tables) [Line Items]
Summary of the RSU activity	​ ​ ​ ​ ​ ​ Vesting Period 2023 2022 Vesting Immediately (1)(2) 3,561,078 1,721,729 Vesting fully on the anniversary of the grant date (3) 1,014,349 476,189 Vesting in thirds on each anniversary of the grant date (4) 8,689,481 464,632 Vesting in fourths on each anniversary of the grant date 404,277 527,800 Total Units Granted 13,669,185 3,190,350 1. Of the 3,561,078 units vesting immediately on grant date, 3,198,648 units were issued to settle liabilities with a carrying amount of $2.8 million, at a weighted average grant date fair value of $0.89 per RSU. 2. During the year ended December 31, 2023, the Company granted 274,912 units to consultants (2022: 649,157 units) resulting in $0.3 million, charged to professional and consulting fees under general and administrative expenses and $ 11 thousand charged to exploration and evaluation activities for the year ended December 31, 2023 (2022: $1.2 million of general and administrative expenses). During the year ended December 31, 2023, the Company also granted 43,478 units to consultants as a prepayment for their services (2022: nil ). 3. During the year ended December 31, 2023, the Company granted 1,014,349 RSUs (2022: 476,189 ) to its non-employee directors under the Company’s Non-employee Director Compensation Policy, which vest upon the Company’s 2024 annual shareholders meeting. The total fair value of units granted as annual grants to the non-employee directors amounted to $700,000 ( $700,000 in 2022). 4. During the year ended December 31, 2023, the Company granted 8,645,465 units, as payment for the 2022 LTIP awards and 44,016 units as a sign-on grant. The 2021 LTIP awards were granted in the fourth quarter of 2021 and totaled 3,500,000 units.
Schedule of company estimated the realization of the vesting conditions	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ Aggregate ​ Weighted ​ ​ average intrinsic average ​ ​ Number of ​ exercise ​ value of ​ contractual ​ ​ Options ​ price per ​ stock ​ life ​ ​ Outstanding ​ option ​ options ​ (years) Outstanding – December 31, 2021 15,503,748 ​ $ 1.40 $ 17,415 ​ 6.33 Cancelled/Forfeited (28,947) ​ ​ 2.60 ​ — ​ — Exercised (118,461) ​ ​ 0.65 ​ — ​ — Outstanding – December 31, 2022 15,356,340 ​ $ 1.40 $ 1,582 ​ 5.11 Granted — ​ ​ — ​ — ​ — Expired (162,100) ​ ​ 0.87 ​ — ​ — Cancelled/Forfeited — ​ ​ — ​ — ​ — Exercised (120,000) ​ ​ 0.65 ​ — ​ — Outstanding – December 31, 2023 15,074,240 ​ $ 1.41 $ 5,425 ​ 4.18 Vested and exercisable – December 31, 2023 14,804,073 ​ $ 1.28 $ 5,425 ​ 4.17
Schedule of company's stock options outstanding	A summary of the Company’s stock options granted and outstanding under the Company’s STIP as at December 31, 2023 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average Number of Number of ​ ​ ​ ​ ​ life to expiry ​ Options ​ Options Expiry Date ​ Exercise price ​ (years) ​ Outstanding ​ Exercisable March 31, 2024 ​ $ 0.65 0.25 73,811 73,811 December 31, 2025 ​ $ 0.65 2.00 11,578 11,578 January 27, 2026 ​ $ 0.52 - $2.59 2.08 975,229 975,229 February 2, 2026 ​ $ 0.65 2.09 57,893 57,893 February 17, 2026 ​ $ 0.22 - $0.52 2.13 431,494 431,494 June 1, 2028 ​ $ 0.65 - $8.64 4.42 12,829,518 12,559,351 June 30, 2028 ​ $ 2.59 4.50 694,717 694,717 ​ ​ ​ ​ ​ ​ 15,074,240 14,804,073
Restricted Stock Units ("RSUs")
Stock Options (Tables) [Line Items]
Summary of the RSU activity	​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ Number of ​ average grant- ​ ​ RSUs ​ date fair value ​ ​ Outstanding ​ per RSU Outstanding – December 31, 2022 3,815,143 $ 2.75 Granted 13,669,185 ​ 0.92 Forfeited ​ (86,700) ​ ​ 0.96 Exercised ​ (4,912,748) ​ ​ 1.57 Outstanding – December 31, 2023 12,484,880 $ 1.23

Loss per Share (Tables)

Loss per Share (Tables)	12 Months Ended
	Dec. 31, 2023
Loss per Share
Schedule of anti-dilutive common equivalent shares	​ ​ ​ ​ ​ ​ ​ ​ For the year ended ​ For the year ended ​ ​ December 31, ​ December 31, ​ 2023 2022 Outstanding options to purchase common shares ​ 24,858,162 ​ 25,140,262 Outstanding RSUs 12,484,880 3,815,143 Outstanding shares under ESPP ​ 8,802 ​ 12,212 Outstanding warrants 28,480,770 36,078,620 Outstanding Special Shares and options to purchase Special Shares 136,239,964 136,239,964 Total anti-dilutive common equivalent shares 202,072,578 201,286,201 ​

Financial Instruments (Tables)

Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2023
Financial Instruments
Schedule of categories of financial instruments	​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023 December 31, 2022 Financial assets ​ ​ Amortized cost ​ ​ Cash $ 6,842 $ 46,876 Receivables and Prepayments ​ ​ 1,978 ​ ​ 2,726 ​ $ 8,820 $ 49,602 ​ ​ ​ ​ ​ ​ ​ Financial liabilities ​ ​ Amortized cost ​ ​ Accounts payable and accrued liabilities $ 31,334 $ 41,614 Fair value through profit or loss ​ — ​ ​ — Royalty liability ​ ​ 14,000 ​ ​ — Warrants liability ​ ​ 1,969 ​ ​ 983 ​ $ 47,303 $ 42,597 ​

Segmented Information (Tables)

Segmented Information (Tables)	12 Months Ended
	Dec. 31, 2023
Segmented Information
Schedule of equipment	​ ​ ​ ​ ​ ​ ​ ​ Equipment December 31, 2023 December 31, 2022 Nauru $ 1,128 $ 1,154 Singapore ​ ​ 1,643 ​ ​ 863 Tonga ​ 5 ​ 7 North America ​ — ​ 1 Total $ 2,776 $ 2,025 ​

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2023
Income Taxes
Schedule of income tax expense at statutory rates for the Company reconciled to the reported loss for the year	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the year ended ​ For the year ended ​ ​ ​ December 31, ​ December 31, ​ ​ 2023 2022 (1) Loss for the year, before taxes ​ $ (73,740) ​ $ (170,887) ​ Canadian Federal and Provincial income tax rates ​ 26.68 % ​ 26.61 % Income tax recovery based on the above rates $ (19,677) $ (45,473) ​ Permanent differences ​ 1,556 ​ 1,926 ​ Effect of differences in future and foreign tax rates ​ 14,038 ​ 36,903 ​ Valuation allowance changes affecting the provision of income taxes ​ 4,124 ​ 6,721 ​ Total income taxes $ 41 $ 77 ​ (1) Comparative amounts for the year ended December 31, 2022 are restated based on actual tax returns filed.
Schedule of deferred income tax assets (liabilities)	​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023 December 31, 2022 Deferred Tax Assets ​ ​ Non-capital losses $ 21,195 $ 16,011 Investments ​ 384 ​ 172 Equipment ​ 260 ​ 79 Share issuance costs ​ 496 ​ 218 Total deferred income tax assets $ 22,335 $ 16,480 Valuation allowance ​ (22,335) ​ (16,480) Deferred tax asset recognized $ — $ — ​ ​ ​ ​ ​ ​ ​ Deferred Tax Liability ​ ​ ​ ​ ​ ​ Difference between the book value and the tax basis of the TOML exploration contract (Note 7) ​ $ (10,675) ​ $ (10,675) Deferred tax liability recognized $ (10,675) $ (10,675) (1) Comparative amounts for the year ended December 31, 2022 are restated based on actual tax returns filed.
Schedule of deductible temporary differences, unused tax losses and unused tax credits	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2023 December 31, 2022 Expiry Date Range ​ ​ ​ ​ ​ ​ ​ ​ ​ Non-capital losses $ 89,333 $ 67,409 See below Investments $ 2,856 $ 1,273 Not applicable Equipment $ 962 $ 291 Not applicable Share issuance costs $ 1,860 $ 821 Not applicable
Schedule of non-capital loss carry-forwards that may be used to offset future taxable income	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Canada Singapore United States Tonga 2035 $ — $ — $ 2 $ — 2041 ​ 3,741 ​ — ​ — ​ — 2042 ​ ​ 13,707 ​ ​ — ​ ​ 1 ​ ​ — 2043 ​ ​ 12,343 ​ ​ — ​ ​ 3 ​ ​ — No expiry ​ — ​ 20,567 ​ — ​ 38,969 Loss carry-forwards ​ $ 29,791 ​ $ 20,567 ​ $ 6 ​ $ 38,969

Quarterly Financial Data (Una_2

Quarterly Financial Data (Unaudited) Restatement of Previously Issued Financial Statements (Tables)	12 Months Ended
	Dec. 31, 2023
Quarterly Financial Data (Unaudited) Restatement of Previously Issued Financial Statements
Schedule of restatement of previously issued quarterly financial statements	The tables below set forth the unaudited condensed consolidated balance sheet information, the unaudited condensed statements of loss and comprehensive loss and the unaudited condensed consolidated statements of cash flows including the amounts as reported, adjustments and the amounts as restated (in thousands, except per share amounts): ​ Condensed Consolidated Balance Sheet Information ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As at March 31, 2023 ​ As at June 30, 2023 ​ As at September 30, 2023 ​ ​ As Previously Restatement ​ ​ ​ ​ As Previously ​ Restatement ​ ​ ​ ​ As Previously ​ Restatement ​ ​ ​ ​ Reported ​ Adjustments As Restated Reported Adjustments As Restated Reported Adjustments As Restated ASSETS ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Current ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash ​ $ 28,390 ​ $ — ​ ​ 28,390 ​ $ 20,006 ​ $ — ​ ​ 20,006 ​ $ 22,548 ​ ​ — $ 22,548 Receivables and prepayments ​ 3,230 ​ — ​ 3,230 ​ 1,637 ​ — ​ 1,637 ​ 5,325 ​ — ​ 5,325 ​ ​ 31,620 ​ — ​ 31,620 ​ 21,643 ​ — ​ 21,643 ​ 27,873 ​ — ​ 27,873 Non-current ​ ​ ​ ​ ​ ​ ​ ​ ​ Exploration contracts ​ 42,900 ​ 250 ​ 43,150 ​ 42,900 ​ 250 ​ 43,150 ​ 42,900 ​ 250 ​ 43,150 Equipment ​ 1,997 ​ — ​ 1,997 ​ 1,970 ​ — ​ 1,970 ​ 2,078 ​ — ​ 2,078 Right-of-use asset ​ — ​ — ​ — ​ — ​ — ​ — ​ 6,198 ​ — ​ 6,198 Investment ​ 8,781 ​ — ​ 8,781 ​ 8,644 ​ — ​ 8,644 ​ 8,525 ​ — ​ 8,525 ​ ​ 53,678 ​ 250 ​ 53,928 ​ 53,514 ​ 250 ​ 53,764 ​ 59,701 ​ 250 ​ 59,951 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ TOTAL ASSETS ​ $ 85,298 ​ $ 250 ​ $ 85,548 ​ $ 75,157 ​ $ 250 ​ $ 75,407 ​ $ 87,574 ​ $ 250 ​ $ 87,824 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ LIABILITIES ​ ​ ​ ​ ​ ​ ​ ​ ​ Current ​ ​ ​ ​ ​ ​ ​ ​ ​ Accounts payable and accrued liabilities ​ 17,544 ​ — ​ 17,544 ​ 18,113 ​ — ​ 18,113 ​ 19,344 ​ — ​ 19,344 ​ ​ 17,544 ​ — ​ 17,544 ​ 18,113 ​ — ​ 18,113 ​ 19,344 ​ — ​ 19,344 Non-current ​ ​ ​ ​ ​ ​ ​ ​ ​ Deferred tax liability ​ 10,675 ​ — ​ 10,675 ​ 10,675 ​ — ​ 10,675 ​ 10,675 ​ — ​ 10,675 Royalty Liability ​ — ​ 14,000 ​ 14,000 ​ — ​ 14,000 ​ 14,000 ​ — ​ 14,000 ​ 14,000 Warrants liability ​ 1,528 ​ — ​ 1,528 ​ 2,314 ​ — ​ 2,314 ​ 2,197 ​ — ​ 2,197 TOTAL LIABILITIES ​ $ 29,747 ​ $ 14,000 ​ $ 43,747 ​ $ 31,102 ​ $ 14,000 ​ $ 45,102 ​ $ 32,216 ​ $ 14,000 ​ $ 46,216 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ EQUITY ​ ​ ​ ​ ​ ​ ​ ​ ​ Common shares (unlimited shares, no par value) ​ 345,090 ​ — ​ 345,090 ​ 345,775 ​ — ​ 345,775 ​ 434,099 ​ — ​ 434,099 Special Shares ​ — ​ — ​ — ​ — ​ — ​ — ​ — ​ — ​ — Additional paid in capital ​ 186,796 ​ — ​ 186,796 ​ 188,722 ​ — ​ 188,722 ​ 124,168 ​ — ​ 124,168 Accumulated other comprehensive loss ​ (1,216) ​ — ​ (1,216) ​ (1,216) ​ — ​ (1,216) ​ (1,216) ​ — ​ (1,216) Deficit ​ (475,119) ​ (13,750) ​ (488,869) ​ (489,226) ​ (13,750) ​ (502,976) ​ (501,693) ​ (13,750) ​ (515,443) TOTAL EQUITY ​ $ 55,551 ​ (13,750) ​ $ 41,801 ​ $ 44,055 ​ (13,750) ​ $ 30,305 ​ $ 55,358 ​ ​ (13,750) ​ $ 41,608 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ TOTAL LIABILITIES AND EQUITY ​ $ 85,298 ​ $ 250 ​ $ 85,548 ​ $ 75,157 ​ $ 250 ​ $ 75,407 ​ $ 87,574 ​ $ 250 ​ $ 87,824 ​ ​ Condensed Consolidated Statements of Loss and Comprehensive Loss ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For three months period ended ​ For six months period ended ​ For nine months period ended ​ ​ March 31, 2023 ​ June 30, 2023 ​ September 30, 2023 ​ ​ As Previously ​ Restatement ​ ​ ​ ​ As Previously ​ Restatement ​ ​ ​ ​ As Previously ​ Restatement ​ ​ ​ ​ Reported Adjustments As Restated Reported Adjustments As Restated Reported Adjustments As Restated Operating expenses ​ ​ ​ ​ ​ ​ ​ ​ ​ Exploration and evaluation expenses ​ $ 7,169 ​ — ​ $ 7,169 ​ $ 15,267 ​ — ​ $ 15,267 ​ $ 23,172 ​ — ​ $ 23,172 General and administrative expenses ​ 6,214 ​ — ​ 6,214 ​ 11,345 ​ — ​ 11,345 ​ 15,958 ​ — ​ 15,958 Operating loss ​ 13,383 ​ — ​ 13,383 ​ 26,612 ​ — ​ 26,612 ​ 39,130 ​ — ​ 39,130 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Other items ​ ​ ​ ​ ​ ​ ​ ​ ​ Equity-accounted investment loss ​ 219 ​ — ​ 219 ​ 356 ​ — ​ 356 ​ 475 ​ — ​ 475 Gain on disposition of asset ​ (13,750) ​ 13,750 ​ — ​ (13,750) ​ 13,750 ​ — ​ (13,750) ​ 13,750 ​ — Change in fair value of warrants liability ​ 544 ​ — ​ 544 ​ 1,331 ​ — ​ 1,331 ​ 1,214 ​ — ​ 1,214 Foreign exchange loss ​ 29 ​ — ​ 29 ​ 52 ​ — ​ 52 ​ 66 ​ — ​ 66 Interest income ​ (454) ​ — ​ (454) ​ (773) ​ — ​ (773) ​ (1,092) ​ — ​ (1,092) Fees and interest on credit facility ​ 27 ​ — ​ 27 ​ 277 ​ — ​ 277 ​ 529 ​ — ​ 529 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loss and comprehensive loss for the year, before tax ​ $ (2) ​ $ 13,750 ​ $ 13,748 ​ $ 14,105 ​ $ 13,750 ​ $ 27,855 ​ $ 26,572 ​ $ 13,750 ​ $ 40,322 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Tax expense ​ — ​ — ​ — ​ — ​ — ​ — ​ — ​ — ​ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loss (gain) and comprehensive loss (gain) for the period, after tax ​ $ (2) ​ $ 13,750 ​ $ 13,748 ​ $ 14,105 ​ $ 13,750 ​ $ 27,855 ​ $ 26,572 ​ $ 13,750 ​ $ 40,322 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Loss per share ​ ​ ​ ​ ​ ​ ​ ​ ​ - basic and diluted ​ — ​ $ 0.05 ​ $ 0.05 ​ $ 0.05 ​ $ 0.05 ​ $ 0.10 ​ $ 0.09 ​ $ 0.05 ​ $ 0.14 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average number of Common Shares outstanding – basic ​ 272,029,603 ​ 272,029,603 ​ 272,029,603 ​ 276,702,050 ​ 276,702,050 ​ 276,702,050 ​ 282,745,892 ​ 282,745,892 ​ 282,745,892 Weighted average number of Common Shares outstanding – diluted ​ 300,376,133 ​ 272,029,603 ​ 272,029,603 ​ 276,702,050 ​ 276,702,050 ​ 276,702,050 ​ 282,745,892 ​ 282,745,892 ​ 282,745,892 ​ ​ Condensed Consolidated Statements of Cash Flows ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For three months period ended ​ For six months period ended ​ For nine months period ended ​ ​ March 31, 2023 ​ June 30, 2023 ​ September 30, 2023 ​ ​ As Previously ​ Restatement ​ ​ ​ As Previously ​ Restatement ​ ​ ​ As Previously ​ Restatement ​ ​ ​ Reported Adjustments As Restated Reported Adjustments As Restated Reported Adjustments As Restated Operating activities Gain/(Loss) for the period 2 (13,750) (13,748) (14,105) (13,750) (27,855) (26,572) (13,750) (40,322) Items not affecting cash: Amortization 88 — 88 175 — 175 262 — 262 Lease expense — — — — — — 318.00 — 318.00 Expenses settled with share-based payments 1,775 — 1,775 4,307 — 4,307 6,839 — 6,839 Expenses to be settled with share-based payments 15 — 15 — — — — — — Equity-accounted investment loss 219 — 219 356 — 356 475 — 475 Gain on disposition of asset (13,750) 13,750 — (13,750) 13,750 — (13,750) 13,750 — Change in fair value of warrants liability 545 — 545 1,331 — 1,331 1,214 — 1,214 Vesting of Allseas Warrant — — — — — — — — — Unrealized foreign exchange movement (20) — (20) (17) — (17) (24) — (24) Changes in working capital: — — — — — — — Receivables and prepayments (469) — (469) 1,123 — 1,123 (2,364) — (2,364) Accounts payable and accrued liabilities (11,877) — (11,877) (11,277) — (11,277) (10,757) — (10,757) Net cash used in operating activities (23,472) — (23,472) (31,857) — (31,857) (44,359) — (44,359) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Investing activities Cash received from investment in Low Carbon Royalties 5,000 (5,000) — 5,000 (5,000) — 5,000 (5,000) — Acquisition of equipment — — — (75) — (75) (175) (175) Net cash provided by (used in) investing activities 5,000 (5,000) — 4,925 (5,000) (75) 4,825 (5,000) (175) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Financing activities Proceeds from Low Carbon Royalties investment — 5,000 5,000 — 5,000 5,000 — 5,000 5,000 Proceeds from Registered Direct Offering — — — — — — 15,723 — 15,723 Expenses paid for Registered Direct Offering — — — — — — (779) — (779) Proceeds from PIPE financing — — — — — — — — — Expenses paid for PIPE financing — — — — — — — — — Proceeds from employee stock plan — — — 49 — 49 49 — 49 Proceeds from exercise of stock options — — — — — — 77 — 77 Proceeds from exercise of warrants by Allseas — — — — — — 116 — 116 Proceeds from issuance of shares — — — 30 — 30 30 — 30 Taxes withheld and paid on share-based compensation — — — — — — — — Net cash provided by financing activities — 5,000 5,000 79 5,000 5,079 15,216 5,000 20,216 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Decrease in cash (18,472) — (18,472) (26,853) — (26,853) (24,318) — (24,318) Impact of exchange rate changes on cash 20 — 20 17 — 17 24 — 24 Cash - beginning of period 46,842 — 46,842 46,842 — 46,842 46,842 — 46,842 Cash - end of period 28,390 — 28,390 20,006 — 20,006 22,548 — 22,548 ​

Nature of Operations (Details)

Nature of Operations (Details) - km²	Dec. 31, 2023	Mar. 31, 2020
NORI
Nature of Operations
Area of exploration granted (in square km)	74,830
TOML
Nature of Operations
Area of exploration granted (in square km)		74,713
Marawa
Nature of Operations
Area of exploration granted (in square km)		74,990

Basis of Presentation - Non con

Basis of Presentation - Non controlling interest (Details)	Dec. 31, 2023
DeepGreen Engineering Pte. Ltd.
Basis of Presentation
Proportion of Interest Held by the Company	100%
DeepGreem Metals ULC
Basis of Presentation
Proportion of Interest Held by the Company	100%
DeepGreen Resources LLC ("DGL")
Basis of Presentation
Proportion of Interest Held by the Company	100%
DeepGreen TOML Holding 1 Ltd.
Basis of Presentation
Proportion of Interest Held by the Company	100%
DeepGreen TOML Holding 2 Ltd.
Basis of Presentation
Proportion of Interest Held by the Company	100%
DeepGreen TOML Singapore Pte. Ltd.
Basis of Presentation
Proportion of Interest Held by the Company	100%
Koloa Moana Resources Ltd.
Basis of Presentation
Proportion of Interest Held by the Company	100%
Nauru Education and Training Foundation Inc.
Basis of Presentation
Proportion of Interest Held by the Company	100%
Nauru Health and Environment Foundation Inc.
Basis of Presentation
Proportion of Interest Held by the Company	100%
Nauru Ocean Resources Inc
Basis of Presentation
Proportion of Interest Held by the Company	100%
Offshore Minerals Pty. Ltd.
Basis of Presentation
Proportion of Interest Held by the Company	100%
The Metals Company Australia Pty Ltd
Basis of Presentation
Proportion of Interest Held by the Company	100%
TMC The Metals Company UK Limited
Basis of Presentation
Proportion of Interest Held by the Company	100%
Tonga Offshore Mining Ltd.
Basis of Presentation
Proportion of Interest Held by the Company	100%

Significant Accounting Polici_4

Significant Accounting Policies (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022	Mar. 04, 2021
Significant Accounting Policies
Transfers amount of fair value measurement levels	$ 0	$ 0
Cash	$ 0	$ 0
Allseas Group S.A
Significant Accounting Policies
Number of warrants issued			11,600,000
Private Warrants
Significant Accounting Policies
Number of warrants issued	9,500,000
Public warrants
Significant Accounting Policies
Number of warrants issued	15,000,000

Significant Accounting Polici_5

Significant Accounting Policies - Equipment (Details)	12 Months Ended
	Dec. 31, 2023
Exploration and other equipment
Property, Plant and Equipment [Line Items]
Depreciation rate	30%
Office equipment
Property, Plant and Equipment [Line Items]
Depreciation rate	30%

Significant Accounting Estima_2

Significant Accounting Estimates and Judgements (Details)	12 Months Ended
	Dec. 31, 2023 item D $ / shares
Significant Accounting Estimates and Judgements
Issue price per share | $ / shares	$ 18
Trading days for redemption of public warrants	20
Consecutive trading days for redemption of public warrants	30
Number of trials for warrants valuation | item	250,000

Receivables and Prepayments (De

Receivables and Prepayments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Aug. 14, 2023
Receivables and Prepayments
Taxes and other receivables	$ 467	$ 117	$ 300
Prepayments	1,511	2,609
Total	$ 1,978	$ 2,726

Equipment (Details)

Equipment (Details) - DeepGreen - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Schedule Of Equipment Line Items
Balance	$ 3,847	$ 2,821
Additions	1,111	1,026
Balance	4,958	3,847
Accumulated depreciation
Balance	(1,822)	(1,405)
Amortization for the year	(360)	(417)
Balance	(2,182)	(1,822)
Net book value
Balance	2,776	2,025
Exploration and other equipment [Member]
Schedule Of Equipment Line Items
Balance	3,826	2,800
Additions	1,111	1,026
Balance	4,937	3,826
Accumulated depreciation
Balance	(1,802)	(1,386)
Amortization for the year	(359)	(416)
Balance	(2,161)	(1,802)
Net book value
Balance	2,776	2,024
Office Equipment [Member]
Schedule Of Equipment Line Items
Balance	21	21
Additions	0
Balance	21	21
Accumulated depreciation
Balance	(20)	(19)
Amortization for the year	(1)	(1)
Balance	$ (21)	(20)
Net book value
Balance		$ 1

Strategic Partnerships - Pilot

Strategic Partnerships - Pilot Mining Test Project (Details) - USD ($)

5 Months Ended

6 Months Ended

9 Months Ended

12 Months Ended

Aug. 14, 2023

Aug. 09, 2023

Feb. 23, 2023

Feb. 21, 2023

Feb. 13, 2023

Nov. 11, 2022

Aug. 12, 2022

Mar. 04, 2021

Jul. 08, 2019

Dec. 31, 2023

Jun. 30, 2023

Sep. 30, 2023

Dec. 31, 2023

Mar. 29, 2019

Finite-Lived Intangible Assets [Line Items]

Number of shares issued to Allseas (Notes 8) (in shares)

4,150,000

5,000,000

37,978,680

Proceeds from issuance of shares

$ 30,000

$ 30,000

$ 30,000

Amount of shares issued to Allseas (Notes 8)

$ 15,910,000

Exercise fee received

$ 115,800

Common Stock

Finite-Lived Intangible Assets [Line Items]

Number of shares issued to Allseas (Notes 8) (in shares)

4,150,000

15,000,000

Amount of shares issued to Allseas (Notes 8)

$ 15,910,000

Completion of the PMTS

Finite-Lived Intangible Assets [Line Items]

Number of shares issued to Allseas (Notes 8) (in shares)

11,600,000

Strategic Alliance with Allseas Pilot Mining Test Project

Finite-Lived Intangible Assets [Line Items]

Number of shares issued to Allseas (Notes 8) (in shares)

10,850,000

Final settlement

$ 10,000,000

Stock issued (in shares)

10,850,000

Common shares per share

$ 1

Third and final payment

$ 10,000,000

Amount of shares issued to Allseas (Notes 8)

$ 900,000

Strategic Alliance with Allseas Pilot Mining Test Project | Common Stock

Finite-Lived Intangible Assets [Line Items]

Shares issued upon the exercise of the warrant

11,578,620

Allseas Group S.A

Finite-Lived Intangible Assets [Line Items]

Subscribed for common shares (in Shares)

6,700,000

Proceeds from issuance of shares

$ 20,000,000

Research and development

8,700,000

Allseas Group S.A | Closing of the Business Combination

Finite-Lived Intangible Assets [Line Items]

Amount payable

$ 10,000,000

Allseas Group S.A | Later of (i) January 1, 2022, and (ii) confirmation of successful collection of North Sea test

Finite-Lived Intangible Assets [Line Items]

Amount payable

10,000,000

Allseas Group S.A | Completion of the PMTS

Finite-Lived Intangible Assets [Line Items]

Amount payable

$ 10,000,000

$ 10,000,000

Number of shares issued to Allseas (Notes 8) (in shares)

10,000,000

Strategic Partnerships - Develo

Strategic Partnerships - Development of Project Zero Offshore Nodule Collection System (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2023	Jun. 30, 2023	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
Finite-Lived Intangible Assets [Line Items]
Exploration and evaluation expenses	$ 7,169	$ 15,267	$ 23,172	$ 49,849	$ 144,599
Project Management Technology Services
Finite-Lived Intangible Assets [Line Items]
Exploration and evaluation expenses				$ 12,100	$ 15,700

Strategic Alliance with Allse_3

Strategic Alliance with Allseas and Affiliates - Exclusive Vessel Use Agreement with Allseas (Details) - USD ($) $ in Thousands				5 Months Ended	9 Months Ended	12 Months Ended
	Aug. 14, 2023	Feb. 21, 2023	Aug. 12, 2022	Dec. 31, 2023	Sep. 30, 2023	Dec. 31, 2023	Jul. 31, 2023
Strategic Partnerships
Lease liability	$ 6,500						$ 6,515
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Fair Value Adjustment of Warrants						Fair Value Adjustment of Warrants
Shares issued to Allseas (Note 8) (in shares)	4,150,000	5,000,000	37,978,680
Lease expense				$ 794	$ 318	$ 795

Strategic Alliance with Allse_4

Strategic Alliance with Allseas and Affiliates - Lease liability and right-of-use asset (Details) - USD ($) $ in Thousands				5 Months Ended	9 Months Ended	12 Months Ended
	Aug. 14, 2023	Feb. 21, 2023	Aug. 12, 2022	Dec. 31, 2023	Sep. 30, 2023	Dec. 31, 2023	Jul. 31, 2023
Lease Liability
Lease liability				$ 6,515
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Fair Value Adjustment of Warrants						Fair Value Adjustment of Warrants
Payments made during the quarter by issuing 4.15 million common shares				6,515
Lease liability	$ 6,500
Right-of-use Asset
Right-of-use Asset				6,515
Lease expense				794	$ 318	$ 795
Right-of-use Asset				$ 5,721	$ 6,198	$ 5,721
Shares issued to Allseas (Note 8) (in shares)	4,150,000	5,000,000	37,978,680
Common stock
Right-of-use Asset
Shares issued to Allseas (Note 8) (in shares)				4,150,000		15,000,000

Strategic Partnerships - Credit

Strategic Partnerships - Credit Facility with Allseas Affiliate (Details) $ in Thousands		12 Months Ended
	Mar. 22, 2023 USD ($) D	Dec. 31, 2023 USD ($)	Mar. 22, 2024 USD ($)	Dec. 31, 2022 USD ($)	Sep. 09, 2021
Related party
Credit Facility with Allseas Affiliate
Aggregate borrowed amount			$ 20,000,000
Unsecured Credit Facility
Credit Facility with Allseas Affiliate
Line of credit facility interest rate term	semi-annually
Line of credit | Allseas and affiliates | Related party
Credit Facility with Allseas Affiliate
Aggregate borrowed amount	$ 25,000
Number of days average considered for basis spread | D	180
Interest rate	4%
Interest paid in kind at maturity					5%
Credit facility interest rate	4%
Underutilization fees		$ 800
Amount payable to Allseas and its affiliates				$ 10,200
Related party transaction, amounts of transaction		$ 13,800

Strategic Partnerships - Other

Strategic Partnerships - Other Activity (Details) - USD ($) $ in Millions		1 Months Ended
	Aug. 14, 2023	Aug. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Direct offering
Finite-Lived Intangible Assets [Line Items]
Gross proceeds	$ 24.9
Class A Warrants | Direct offering
Finite-Lived Intangible Assets [Line Items]
Sale of stock, number of shares		1,750,000
Allseas | Direct offering
Finite-Lived Intangible Assets [Line Items]
Gross proceeds		$ 7
Allseas | Common Stock
Finite-Lived Intangible Assets [Line Items]
Shares owned			53,800,000	23,700,000
Percentage of common stock shares outstanding			17.60%	8.90%
Allseas | Common Stock | Direct offering
Finite-Lived Intangible Assets [Line Items]
Sale of stock, number of shares		3,500,000

Investment in Low Carbon Roya_3

Investment in Low Carbon Royalties (Details) - USD ($)									1 Months Ended	5 Months Ended	12 Months Ended
	Aug. 14, 2023	Aug. 09, 2023	Mar. 21, 2023	Feb. 23, 2023	Feb. 21, 2023	Feb. 13, 2023	Aug. 12, 2022	Mar. 04, 2021	Aug. 31, 2023	Dec. 31, 2023	Dec. 31, 2023	Dec. 31, 2022	Sep. 30, 2023	Jul. 31, 2023	Jun. 30, 2023	Mar. 31, 2023
Strategic Partnerships
Shares issued to Allseas (Note 8)											$ 15,910,000
Number of shares issued to Allseas (Notes 8) (in shares)	4,150,000				5,000,000		37,978,680
Conversion of restricted share units (in shares)					5,000,000
Right-of-use asset										$ 5,721,000	5,721,000		$ 6,198,000	$ 6,515,000
Percentage of contribution to gross royalty					2%
Percentage of repurchase of gross royalty					75%
Percentage of reduction in NORI royalty					0.50%
Percentage of owned carbon royalty					1.56%
Percentage of common stock shares received					35%
Royalty expense					$ 5,000,000
Increase in percentage of gross royalty in second license block			1.44%
Investment			$ 9,000,000							8,429,000	8,429,000		8,525,000		$ 8,644,000	$ 8,781,000
Equity-accounted investment loss for the year											(571,000)
Exercise fee received		$ 115,800
Cash received										(5,000,000)	(5,000,000)
Fair value of NORI Royalty										14,000,000	14,000,000
Royalty liability										$ 14,000,000	14,000,000		$ 14,000,000		$ 14,000,000	$ 14,000,000
Registered direct offering
Strategic Partnerships
Gross proceeds	$ 24,900,000
Minimum
Strategic Partnerships
Increase in percentage of gross royalty in first license block			1.56%
Decrease in percentage of gross royalty			32%
Maximum
Strategic Partnerships
Increase in percentage of gross royalty in first license block			3.13%
Decrease in percentage of gross royalty			35%
Common stock
Strategic Partnerships
Shares issued to Allseas (Note 8)											$ 15,910,000
Number of shares issued to Allseas (Notes 8) (in shares)										4,150,000	15,000,000
Conversion of restricted share units (in shares)											4,912,747	2,877,068
Warrant [Member] | Registered direct offering
Strategic Partnerships
Number of shares issued									1,750,000
TOML Acquisition.
Strategic Partnerships
Royalty liability										$ 14,000,000	$ 14,000,000
Strategic Alliance with Allseas Pilot Mining Test Project
Strategic Partnerships
Final settlement						$ 10,000,000
Stock issued (in shares)						10,850,000
Common shares per share						$ 1
Third and final payment				$ 10,000,000
Shares issued to Allseas (Note 8)								$ 900,000
Number of shares issued to Allseas (Notes 8) (in shares)				10,850,000
Strategic Alliance with Allseas Pilot Mining Test Project | Common stock
Strategic Partnerships
Shares issued upon the exercise of the warrant		11,578,620
Allseas | Registered direct offering
Strategic Partnerships
Gross proceeds									$ 7,000,000
Allseas | Common stock
Strategic Partnerships
Shares owned										53,800,000	53,800,000	23,700,000
Percentage of common stock shares outstanding										17.60%	17.60%	8.90%
Allseas | Common stock | Registered direct offering
Strategic Partnerships
Number of shares issued									3,500,000
Low carbon royalties
Strategic Partnerships
Equity-accounted investment loss for the year											$ 600,000

Investment in Low Carbon Roya_4

Investment in Low Carbon Royalties (Details) - Company's share of the net loss generated by the Low Carbon Royalties - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Mar. 21, 2023
Strategic Partnerships
Fair value of NORI Royalty	$ 14,000
Cash received	(5,000)
Cost of Investment on Closing Date	9,000
Equity-accounted investment loss for the year	(571)
Investment as at December 31, 2023	$ 8,429	$ 8,525	$ 8,644	$ 8,781	$ 9,000

Investment in Low Carbon Roya_5

Investment in Low Carbon Royalties - Financial Results Of Low Carbon Royalties (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022
Schedule of Equity Method Investments [Line Items]
Current Assets	$ 8,820	$ 27,873	$ 21,643	$ 31,620	$ 49,602
Non-Current Assets	60,076	59,951	53,764	53,928	45,175
Current Liabilities	31,334	$ 19,344	$ 18,113	$ 17,544	$ 41,614
Low carbon royalties
Schedule of Equity Method Investments [Line Items]
Current Assets	1,091
Non-Current Assets	26,315
Current Liabilities	131
Royalty Income	399
Total Revenue	480
Comprehensive Income (Loss) for the year	$ (1,747)

Exploration Contracts (Details)

Exploration Contracts (Details) $ in Thousands						6 Months Ended	9 Months Ended	12 Months Ended
	Aug. 14, 2023 shares	Feb. 21, 2023 shares	Aug. 12, 2022 shares	Mar. 31, 2020 USD ($)	Jul. 22, 2011 USD ($)	Jun. 30, 2023 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)	Mar. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Jan. 19, 2015
Finite-Lived Intangible Assets [Line Items]
Number of shares issued to Allseas (Notes 8) (in shares) | shares	4,150,000	5,000,000	37,978,680
Total value						$ 345,775	$ 434,099	$ 438,239	$ 345,090	$ 332,882
Proceeds from issuance of shares						$ 30	$ 30	$ 30
TOML Acquisition.
Finite-Lived Intangible Assets [Line Items]
Metric tones of polymetallic nodules (in Grams)				32,000
Exploration contracts				$ 42,700
Deferred tax liability				$ 10,700
Nauru Ocean Resources Inc [Member] | NORI Exploration Contract [Member]
Finite-Lived Intangible Assets [Line Items]
Application fee					$ 300
Term (in year)								15 years
Renewable for successive term								5 years
Payments to Acquire Mining Assets					$ 300
Marawa Research and Exploration Limited | Marawa Option Agreement [Member]
Finite-Lived Intangible Assets [Line Items]
Term (in year)											15 years
Renewable for successive term								5 years
Tonga Off shore Mining Limited | TOML Exploration Contract [Member]
Finite-Lived Intangible Assets [Line Items]
Term (in year)								15 years
Renewable for successive term								5 years

Exploration Contracts - Reconci

Exploration Contracts - Reconciliation of the Company's explorations contracts (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023
Finite-Lived Intangible Assets [Line Items]
Balance at the beginning	$ 43,150	$ 43,150	$ 43,150	$ 43,150
Balance at the ending	43,150	$ 43,150	$ 43,150	43,150
NORI Exploration Contract [Member]
Finite-Lived Intangible Assets [Line Items]
Balance at the beginning				250
Balance at the ending	250
Marawa Option Agreement [Member]
Finite-Lived Intangible Assets [Line Items]
Balance at the beginning				199
Balance at the ending	199
TOML Exploration Contract [Member]
Finite-Lived Intangible Assets [Line Items]
Balance at the beginning				$ 42,701
Balance at the ending	$ 42,701

Exploration Contracts - Explora

Exploration Contracts - Exploration and evaluation expenses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2023	Jun. 30, 2023	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
Exploration and Evaluation Expenses
Environmental Studies				$ 16,421	$ 38,022
Exploration Labor				8,206	6,020
Share-Based Compensation (Note 15)				5,033	8,488
Mining, Technological and Process Development				14,956	1,988
PMTS					17,819
Prefeasibility Studies				1,345
Allseas Warrant (Note 13)					69,900
Sponsorship, Training and Stakeholder Engagement				3,446	1,561
Other				442	801
Exploration and evaluation expenses	$ 7,169	$ 15,267	$ 23,172	49,849	144,599
Restricted stock units
Exploration and Evaluation Expenses
Sponsorship, Training and Stakeholder Engagement				80	0
NORI Exploration Contract
Exploration and Evaluation Expenses
Environmental Studies				16,421	38,022
Exploration Labor				7,268	4,420
Share-Based Compensation (Note 15)				4,444	6,086
Mining, Technological and Process Development				13,694	1,823
PMTS					15,603
Prefeasibility Studies				1,345
Allseas Warrant (Note 13)					62,910
Sponsorship, Training and Stakeholder Engagement				2,248	891
Other				433	706
Exploration and evaluation expenses				45,853	130,461
Marawa Option Agreement
Exploration and Evaluation Expenses
Exploration Labor				227	758
Share-Based Compensation (Note 15)				146	1,167
Mining, Technological and Process Development					47
PMTS					670
Sponsorship, Training and Stakeholder Engagement				202	194
Other					16
Exploration and evaluation expenses				575	2,852
TOML Exploration Contract
Exploration and Evaluation Expenses
Exploration Labor				711	842
Share-Based Compensation (Note 15)				443	1,235
Mining, Technological and Process Development				1,262	118
PMTS					1,546
Allseas Warrant (Note 13)					6,990
Sponsorship, Training and Stakeholder Engagement				996	476
Other				9	79
Exploration and evaluation expenses				$ 3,421	$ 11,286

General and Administrative Ex_3

General and Administrative Expenses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2023	Jun. 30, 2023	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
General and administrative expenses	$ 6,214	$ 11,345	$ 15,958	$ 22,540	$ 29,518
Restricted stock units
Professional and consulting fees including equity (RSU) settled expenses				400	1,000
Investor relations including equity (RSU) settled expenses				0	300
Professional and consulting fees
General and administrative expenses				6,584	6,795
Investor relations
General and administrative expenses				1,547	1,514
Office and sundry
General and administrative expenses				3,503	4,926
Salaries and wages
General and administrative expenses				4,995	5,921
Director fees
General and administrative expenses				774	788
Share-based compensations
General and administrative expenses				4,122	8,596
Transfer agent and filing fees
General and administrative expenses				363	378
Travel expenses
General and administrative expenses				609	$ 600
Other expenses
General and administrative expenses				$ 43

Financing Activity - Registered

Financing Activity - Registered direct offering (Details) - USD ($) $ / shares in Units, $ in Thousands			9 Months Ended	12 Months Ended
	Jan. 31, 2024	Aug. 14, 2023	Sep. 30, 2023	Dec. 31, 2023	Jan. 30, 2024
Financing Activity
Proceeds from Registered Direct Offering			$ 15,723	$ 15,923
Expenses paid for Registered Direct Offering			$ 779	$ 1,182
Class A Warrant | Subsequent event
Financing Activity
Number of warrants issued	2,250,000
Common stock
Financing Activity
Number of issuance of shares under Registered Direct Offering (Note 12) (in shares)				7,961,540
Direct offering
Financing Activity
Gross proceeds		$ 24,900
Net proceeds		$ 23,600
Proceeds from Registered Direct Offering				$ 15,900
Expenses paid for Registered Direct Offering				1,300
Net proceeds from Registered Direct Offering				$ 14,600
Direct offering | Subsequent event
Financing Activity
Proceeds from Registered Direct Offering	$ 9,000
Remaining committed fund					$ 9,000
Direct offering | Class A Warrant
Financing Activity
Share price		$ 2
Exercise price of warrants		$ 3
Number of warrants issued		3,980,770		3,980,770
Direct offering | Class A Warrant | Subsequent event
Financing Activity
Number of shares agreed to sell and issue					2,250,000
Direct offering | Class A Warrant | Convertible Common Stock [Member]
Financing Activity
Net proceeds from Registered Direct Offering				$ 3,200
Direct offering | Common stock
Financing Activity
Number of shares agreed to sell and issue		12,461,540
Number of issuance of shares under Registered Direct Offering (Note 12) (in shares)				7,961,540
Net proceeds from Registered Direct Offering				$ 11,400
Direct offering | Common stock | Subsequent event
Financing Activity
Number of shares agreed to sell and issue					4,500,000
Direct offering | Common stock | Class A Warrant
Financing Activity
Number of shares agreed to sell and issue		6,230,770

Financing Activity - PIPE Finan

Financing Activity - PIPE Financing (Details)					6 Months Ended	9 Months Ended	12 Months Ended
	Aug. 14, 2023 shares	Feb. 21, 2023 shares	Aug. 12, 2022 shares	Aug. 11, 2022 item	Jun. 30, 2023 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($) $ / shares shares
Financing Activity
Shares issued to Allseas (Note 8) (in shares) | shares	4,150,000	5,000,000	37,978,680
Proceeds from issuance of shares					$ 30,000	$ 30,000	$ 30,000
Securities purchase agreement
Financing Activity
Number of securities purchase agreements				3				37,978,680
Proceeds from issuance of shares								$ 30,400,000
Securities purchase agreement | Placement agent
Financing Activity
Common shares per share | $ / shares								$ 0.80
Placement agent fees and offering expenses								$ 1,000,000
Placement agent fees and offering expenses settled by issuing shares								$ 200,000
Number of shares issued to settle placement fee and offering expenses | shares								287,500

Warrants (Details)

Warrants (Details)			3 Months Ended	12 Months Ended
	Aug. 09, 2023 USD ($)	Jul. 26, 2023 shares	Dec. 31, 2022 USD ($)	Dec. 31, 2023 USD ($) D $ / shares shares	Dec. 31, 2022 USD ($)	Aug. 14, 2023 $ / shares shares	Oct. 09, 2021 $ / shares
Class of Warrant or Right
Issue price per share | $ / shares				$ 18
Trading days for redemption of public warrants | D				20
Consecutive trading days for redemption of public warrants | D				30
Vesting of Allseas Warrant | $					$ 69,900,000
Exercise fee received | $	$ 115,800
Public warrants
Class of Warrant or Right
Number of warrants issued | shares				15,000,000
Private Warrants
Class of Warrant or Right
Fair value of outstanding recorded as warrants liability | $			$ 983,000	$ 1,969,000	$ 983,000
Number of warrants issued | shares				9,500,000
Public warrants
Class of Warrant or Right
Number of warrants outstanding | shares				15,000,000
Trading days for redemption of public warrants | D				20
Consecutive trading days for redemption of public warrants | D				30
Number of shares issuable per warrant | shares				0
Exercise price of warrants | $ / shares				$ 0.365			$ 11.50
Redemption price per warrant (in dollars per share) | $ / shares				$ 0.01
Minimum threshold written notice period for redemption of public warrants				30 days
Threshold trading days for calculating the average closing price | D				10
Public warrants | Redemption of warrants when price per share of class common stock equals or exceeds 18.00
Class of Warrant or Right
Issue price per share | $ / shares				$ 18
Private placement warrants
Class of Warrant or Right
Number of warrants outstanding | shares				9,500,000
Value of outstanding Public Warrants | $				$ 2,000,000
Redemption price per warrant (in dollars per share) | $ / shares				$ 0.01
Threshold trading days for calculating the average closing price | D				10
Allseas Warrants
Class of Warrant or Right
Vesting of Allseas Warrant | $			$ 69,900,000
Shares issued upon the exercise of the warrant | shares		11,578,620
Exercise fee received | $	$ 115,800,000
Allseas Warrants | Pilot mining test system completed by november 2022
Class of Warrant or Right
Vesting of Allseas warrants (in warrants) | shares				11,600,000
Class A Warrants
Class of Warrant or Right
Consecutive trading days for redemption of public warrants | D				30
Redemption price per warrant (in dollars per share) | $ / shares				$ 0.0001
Minimum threshold written notice period for redemption of public warrants				10 days
Class A Warrants | Registered direct offering
Class of Warrant or Right
Number of warrants issued | shares				3,980,770		3,980,770
Exercise price of warrants | $ / shares						$ 3
Common stock of per shares (in Dollars per share) | $ / shares						$ 2

Warrants - Fair value of warran

Warrants - Fair value of warrant liabilities (Details) - Private Warrants $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)
Changes in the fair value of warrants liability:
Warrants liability as at December 31, 2022	$ 983
Increase in fair value of warrants liability	986
Warrants liability as at December 31, 2023	$ 1,969

Warrants - Fair value measureme

Warrants - Fair value measurements assumptions (Details) - Private Warrants - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Class of Warrant or Right
Exercise price	$ 11.50	$ 11.50
Share price	$ 1.10	$ 0.77
Volatility	105.34%	88.05%
Term	2 years 8 months 8 days	3 years 8 months 8 days
Risk-free rate	3.98%	4.04%
Dividend yield	0%	0%

Warrants - Class A Warrants (De

Warrants - Class A Warrants (Details) $ / shares in Units, $ in Thousands		9 Months Ended	12 Months Ended
	Jan. 31, 2024 USD ($) shares	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($) D $ / shares shares	Aug. 14, 2023 $ / shares shares	Jun. 30, 2023 USD ($)	Mar. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Class of Warrant or Right
Consecutive trading days for redemption of public warrants | D			30
Proceeds from Registered Direct Offering | $		$ 15,723	$ 15,923
Additional paid-in capital | $		$ 124,168	122,797		$ 188,722	$ 186,796	$ 184,960
Registered direct offering
Class of Warrant or Right
Proceeds from Registered Direct Offering | $			$ 15,900
Registered direct offering | Subsequent event
Class of Warrant or Right
Proceeds from Registered Direct Offering | $	$ 9,000
Class A Warrants
Class of Warrant or Right
Share price | $ / shares				$ 1.41
Consecutive trading days for redemption of public warrants | D			30
Threshold cancellation of unexercised warrants offering | $ / shares			$ 6.50
Redemption price per warrant (in dollars per share) | $ / shares			$ 0.0001
Minimum threshold written notice period for redemption of public warrants			10 days
Additional paid-in capital | $			$ 3,200
Class A Warrants | Subsequent event
Class of Warrant or Right
Number of warrants issued | shares	2,250,000
Class A Warrants | Registered direct offering
Class of Warrant or Right
Number of warrants issued | shares			3,980,770	3,980,770
Share price | $ / shares				$ 0.80
Exercise price of warrants | $ / shares				$ 3

Warrants - Fair value measure_2

Warrants - Fair value measurements assumptions of the Class A Warrants (Details) - Class A Warrants	Aug. 14, 2023 $ / shares
Class of Warrant or Right
Exercise price	$ 3
Share price	1.41
Call price threshold	$ 6.50
Volatility	107.08%
Term	4 years 4 months 17 days
Risk-free rate	4.32%
Dividend yield	0%

Common Shares - Schedule of aut

Common Shares - Schedule of authorized, issued and outstanding common shares and special shares (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Schedule Of Authorized And Issued Shares Capital [Line Items]
Common Stock, Shares Authorized, Unlimited [Fixed List]	Unlimited
Common shares, issued	306,558,710	266,812,131
Ordinary shares, outstanding	306,558,710
Class A special shares
Schedule Of Authorized And Issued Shares Capital [Line Items]
Special shares, authorized	5,000,000
Special shares, no par value	$ 0
Common shares, issued	4,448,259
Ordinary shares, outstanding	4,448,259
Class B special shares
Schedule Of Authorized And Issued Shares Capital [Line Items]
Special shares, authorized	10,000,000
Special shares, no par value	$ 0
Common shares, issued	8,896,399
Ordinary shares, outstanding	8,896,399
Class C special shares
Schedule Of Authorized And Issued Shares Capital [Line Items]
Special shares, authorized	10,000,000
Special shares, no par value	$ 0
Common shares, issued	8,896,399
Ordinary shares, outstanding	8,896,399
Class D special shares
Schedule Of Authorized And Issued Shares Capital [Line Items]
Special shares, authorized	20,000,000
Special shares, no par value	$ 0
Common shares, issued	17,792,922
Ordinary shares, outstanding	17,792,922
Class E special shares
Schedule Of Authorized And Issued Shares Capital [Line Items]
Special shares, authorized	20,000,000
Special shares, no par value	$ 0
Common shares, issued	17,792,922
Ordinary shares, outstanding	17,792,922
Class F special shares
Schedule Of Authorized And Issued Shares Capital [Line Items]
Special shares, authorized	20,000,000
Special shares, no par value	$ 0
Common shares, issued	17,792,922
Ordinary shares, outstanding	17,792,922
Class G special shares
Schedule Of Authorized And Issued Shares Capital [Line Items]
Special shares, authorized	25,000,000
Special shares, no par value	$ 0
Common shares, issued	22,241,179
Ordinary shares, outstanding	22,241,179
Class H special shares
Schedule Of Authorized And Issued Shares Capital [Line Items]
Special shares, authorized	25,000,000
Special shares, no par value	$ 0
Common shares, issued	22,241,179
Ordinary shares, outstanding	22,241,179
Class I special shares
Schedule Of Authorized And Issued Shares Capital [Line Items]
Special shares, authorized	500,000
Special shares, no par value	$ 0
Common shares, issued	500,000
Ordinary shares, outstanding	500,000
Class J special shares
Schedule Of Authorized And Issued Shares Capital [Line Items]
Special shares, authorized	741,000
Special shares, no par value	$ 0
Common shares, issued	741,000
Ordinary shares, outstanding	741,000

Common Shares (Details)

Common Shares (Details) - Common Stock	12 Months Ended
	Dec. 31, 2023 Vote D
Class of Stock [Line Items]
Threshold trading days within any thirty trading day period for automatic conversion of special shares	20
Threshold consecutive trading day period for automatic conversion of special shares	30
Common Stock, Number Of Votes Per Share | Vote	1

Common Shares -Special Shares C

Common Shares -Special Shares Class (Details)	12 Months Ended
	Dec. 31, 2023 $ / shares shares
Class A special shares
Class of Stock [Line Items]
Share Trigger price | $ / shares	$ 15
Special Shares | shares	5,000,000
Class B special shares
Class of Stock [Line Items]
Share Trigger price | $ / shares	$ 25
Special Shares | shares	10,000,000
Class C special shares
Class of Stock [Line Items]
Share Trigger price | $ / shares	$ 35
Special Shares | shares	10,000,000
Class D special shares
Class of Stock [Line Items]
Share Trigger price | $ / shares	$ 50
Special Shares | shares	20,000,000
Class E special shares
Class of Stock [Line Items]
Share Trigger price | $ / shares	$ 75
Special Shares | shares	20,000,000
Class F special shares
Class of Stock [Line Items]
Share Trigger price | $ / shares	$ 100
Special Shares | shares	20,000,000
Class G special shares
Class of Stock [Line Items]
Share Trigger price | $ / shares	$ 150
Special Shares | shares	25,000,000
Class H special shares
Class of Stock [Line Items]
Share Trigger price | $ / shares	$ 200
Special Shares | shares	25,000,000
Class I special shares
Class of Stock [Line Items]
Share Trigger price | $ / shares	$ 50
Special Shares | shares	500,000
Class J special shares
Class of Stock [Line Items]
Share Trigger price | $ / shares	$ 12
Special Shares | shares	741,000

Common Shares - Schedule of com

Common Shares - Schedule of common shares (Details) - USD ($) $ in Thousands				5 Months Ended	12 Months Ended
	Aug. 14, 2023	Feb. 21, 2023	Aug. 12, 2022	Dec. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Class of Stock [Line Items]
Number of beginning balance					266,812,131
Balance					$ 41,505	$ 92,751
Amount of issuance of shares under Registered Direct Offering (Note 12)					14,599
Amount of exercise of warrant by Allseas (Note 13)					116
Number of shares issued to Allseas (Notes 8) (in shares)	4,150,000	5,000,000	37,978,680
Amount of shares issued to Allseas (Notes 8)					15,910
Number of issuance of shares under PIPE financing (Note 12)						29,621
Amount of exercise of stock options					77	76
Conversion of restricted share units (in shares)		5,000,000
Conversion of restricted share units					30	(70)
Amount of share purchase under Employee Stock Purchase Plan (Note 15)					$ 102	$ 114
Number of ending balance				306,558,710	306,558,710	266,812,131
Balance				$ 10,918	$ 10,918	$ 41,505
Common Stock
Class of Stock [Line Items]
Number of beginning balance					266,812,131	225,432,493
Balance					$ 332,882	$ 296,051
Number of issuance of shares under Registered Direct Offering (Note 12) (in shares)					7,961,540
Amount of issuance of shares under Registered Direct Offering (Note 12)					$ 11,420
Number of exercise of warrant by Allseas (Note 13) (in shares)					11,578,620
Amount of exercise of warrant by Allseas (Note 13)					$ 70,016
Number of shares issued to Allseas (Notes 8) (in shares)				4,150,000	15,000,000
Amount of shares issued to Allseas (Notes 8)					$ 15,910
Number of issuance of shares under PIPE financing (Note 12) (in shares)						38,266,180
Number of issuance of shares under PIPE financing (Note 12)						$ 29,621
Number of exercise of stock options (in Shares)					120,000	118,461
Amount of exercise of stock options					$ 144	$ 142
Conversion of restricted share units (in shares)					4,912,747	2,877,068
Conversion of restricted share units					$ 7,720	$ 6,875
Number of share purchase under Employee Stock Purchase Plan (Note 15) (in shares)					173,672	117,929
Amount of share purchase under Employee Stock Purchase Plan (Note 15)					$ 147	$ 193
Number of ending balance				306,558,710	306,558,710	266,812,131
Balance				$ 438,239	$ 438,239	$ 332,882
Common Stock | Direct offering
Class of Stock [Line Items]
Number of issuance of shares under Registered Direct Offering (Note 12) (in shares)					7,961,540

Share-Based Compensation (Detai

Share-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Mar. 04, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-Based Compensation
Intrinsic value		$ 5,425	$ 1,582	$ 17,415
Number of stock options outstanding (in shares)		15,074,240	15,356,340	15,503,748
Sharebased Payment Arrangement Tranche One Member
Share-Based Compensation
Market Capitalizations		$ 3,000,000
Sharebased Payment Arrangement Tranche Two Member
Share-Based Compensation
Market Capitalizations		6,000,000
General and administration expenses
Share-Based Compensation
Share based compensation expense			$ 67
Exploration and evaluation activities
Share-Based Compensation
Share based compensation expense		200
Short-Term Incentive Plan
Share-Based Compensation
Total grant date fair value of options vested		1,500
Share based compensation expense		$ 47,000
Weighted-average recognition period term		1 year
Share price		$ 1.10
Number of stock options outstanding (in shares)		15,074,240
Number of stock options granted (in Shares)		0
Long-term Incentive Plan
Share-Based Compensation
Share based compensation expense		$ 23,000
Intrinsic value of stock option		188,000
Intrinsic value		$ 4,400
Number of stock options outstanding (in shares)		9,783,922
Number of stock options granted (in Shares)	9,783,922		0
Number of stock options exercise price (in Dollars per share)	$ 0.65	$ 0
Long-term Incentive Plan | Sharebased Payment Arrangement Tranche One Member
Share-Based Compensation
Dividend rate percentage		25%
Market Capitalizations		$ 3,000,000
Derived Per Share		$ 5.59
Derived Service Periods		3 months 29 days
Long-term Incentive Plan | Sharebased Payment Arrangement Tranche Two Member
Share-Based Compensation
Dividend rate percentage		35%
Market Capitalizations		$ 6,000,000
Derived Per Share		$ 5.42
Derived Service Periods		1 year 4 months 28 days
Long-term Incentive Plan | Sharebased Payment Arrangement Tranche Three Member
Share-Based Compensation
Dividend rate percentage		20%
Long-term Incentive Plan | Sharebased Payment Arrangement Tranche Four Member
Share-Based Compensation
Dividend rate percentage		20%
RSU
Share-Based Compensation
Share based compensation expense		$ 8,600	$ 7,500
RSU | General and administration expenses
Share-Based Compensation
Share based compensation expense		3,800	3,800
RSU | Exploration and evaluation activities
Share-Based Compensation
Share based compensation expense		4,800	3,700
Equity option
Share-Based Compensation
Share based compensation expense		500	9,500
Equity option | General and administration expenses
Share-Based Compensation
Share based compensation expense		$ 300	4,800
Equity option | Exploration and evaluation activities
Share-Based Compensation
Share based compensation expense			$ 4,700
2021 Incentive Equity Plan
Share-Based Compensation
Aggregate number of common shares reserved for issuance under the plan		44,372,170
Additional shares including to the plan 2022		10,672,485
Common Shares issued and outstanding percentage		4%
2021 Incentive Equity Plan | Non-employee directors
Share-Based Compensation
Stock option number of shares outstanding (in shares)		2,243,853

Share-based compensation (Det_2

Share-based compensation (Details) - Schedule of the Company's stock options in the Company's STIP - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-Based Compensation
Weighted average exercise price, beginning balance (in Dollars per share)	$ 1.40	$ 1.40
Weighted average contractual life (years)	4 years 2 months 4 days	5 years 1 month 9 days	6 years 3 months 29 days
Options Outstanding, Expired	(162,100)
Weighted average exercise price, Expired (in Dollars per share)	$ 0.87
Options Outstanding, Cancelled/Forfeited		(28,947)
Weighted average exercise price, Cancelled/Forfeited		2.60
Options Outstanding, Exercised	(120,000)	(118,461)
Weighted average exercise price, Exercised (in Dollars per share)	$ 0.65	$ 0.65
Weighted average exercise price, ending balance (in Dollars per share)	$ 1.41	$ 1.40	$ 1.40
Options Outstanding, Vested and exercisable	14,804,073
Weighted average exercise price, Vested and exercisable (in Dollars per share)	$ 1.28
Aggregate Intrinsic value of stock options, Vested and exercisable (in Dollars)	$ 5,425
Weighted average contractual life (years), Vested and exercisable	4 years 2 months 1 day

Share-Based Compensation - Sche

Share-Based Compensation - Schedule of company's stock options granted and outstanding under the STIP (Details) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Class of Warrant or Right [Line Items]
Options Outstanding	15,074,240
Options Exercisable	14,804,073
March 31, 2024
Class of Warrant or Right [Line Items]
Expiry Date	Mar. 31, 2024
Exercise price	0.65
Weighted average life to expiry (years)	3 months
Options Outstanding	73,811
Options Exercisable	73,811
December 31, 2025
Class of Warrant or Right [Line Items]
Expiry Date	Dec. 31, 2025
Exercise price	0.65
Weighted average life to expiry (years)	2 years
Options Outstanding	11,578
Options Exercisable	11,578
January 27, 2026
Class of Warrant or Right [Line Items]
Expiry Date	Jan. 27, 2026
Weighted average life to expiry (years)	2 years 29 days
Options Outstanding	975,229
Options Exercisable	975,229
January 27, 2026 | Minimum
Class of Warrant or Right [Line Items]
Exercise price	0.52
January 27, 2026 | Maximum
Class of Warrant or Right [Line Items]
Exercise price	$2.59
February 2, 2026
Class of Warrant or Right [Line Items]
Expiry Date	Feb. 02, 2026
Exercise price	0.65
Weighted average life to expiry (years)	2 years 1 month 2 days
Options Outstanding	57,893
Options Exercisable	57,893
February 17, 2026
Class of Warrant or Right [Line Items]
Expiry Date	Feb. 17, 2026
Weighted average life to expiry (years)	2 years 1 month 17 days
Options Outstanding	431,494
Options Exercisable	431,494
February 17, 2026 | Minimum
Class of Warrant or Right [Line Items]
Exercise price	0.22
February 17, 2026 | Maximum
Class of Warrant or Right [Line Items]
Exercise price	$0.52
June 1, 2028
Class of Warrant or Right [Line Items]
Expiry Date	Jun. 01, 2028
Weighted average life to expiry (years)	4 years 5 months 1 day
Options Outstanding	12,829,518
Options Exercisable	12,559,351
June 1, 2028 | Minimum
Class of Warrant or Right [Line Items]
Exercise price	0.65	2.59
June 1, 2028 | Maximum
Class of Warrant or Right [Line Items]
Exercise price	$8.64
June 30, 2028
Class of Warrant or Right [Line Items]
Expiry Date	Jun. 30, 2028
Exercise price	2.59
Weighted average life to expiry (years)	4 years 6 months
Options Outstanding	694,717
Options Exercisable	694,717

Share-Based Compensation - Rest

Share-Based Compensation - Restricted Stock Units (Details) - USD ($)	3 Months Ended	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2023	Dec. 31, 2022
Vesting Period
Aggregate vested units outstanding		746,445
General and administration expenses
Vesting Period
Share based compensation expense			$ 67,000
Exploration and evaluation activities
Vesting Period
Share based compensation expense		$ 200,000
Restricted stock units
Vesting Period
Granted		13,669,185	3,190,350
Shares issued		3,198,648
Amount to settle liabilities		$ 2,800,000
Weighted average grant date fair value		$ 0.89
Share based compensation expense		$ 8,600,000	$ 7,500,000
Total unrecognized share-based compensation expense		6,900,000	6,100,000
Fair value of shares vested		$ 8,300,000	$ 7,200,000
Aggregate vested units outstanding		12,484,880	3,815,143
Restricted stock units | As prepayment for the services
Vesting Period
Granted		43,478	0
Restricted stock units | As payment for the 2022 LTIP awards
Vesting Period
Granted		8,645,465
Restricted stock units | As payment for the 2021 LTIP awards
Vesting Period
Granted	3,500,000
Restricted stock units | As a sign-on grant
Vesting Period
Granted		44,016
Restricted stock units | General and administration expenses
Vesting Period
Share based compensation expense		$ 3,800,000	$ 3,800,000
Restricted stock units | Exploration and evaluation activities
Vesting Period
Share based compensation expense		$ 4,800,000	$ 3,700,000
Restricted stock units | Consultant
Vesting Period
Granted		274,912	649,157
Restricted stock units | Consultant | General and administration expenses
Vesting Period
Professional and consulting fees		$ 300,000	$ 1,200,000
Restricted stock units | Consultant | Exploration and evaluation activities
Vesting Period
Professional and consulting fees		$ 11,000
Restricted stock units | Non-Employee Directors
Vesting Period
Granted		1,014,349	476,189
Total fair value of units granted		$ 700,000	$ 700,000
Vesting Immediately | Restricted stock units
Vesting Period
Granted		3,561,078	1,721,729
Vesting fully on the anniversary of the grant date | Restricted stock units
Vesting Period
Granted		1,014,349	476,189
Vesting in thirds on each anniversary of the grant date | Restricted stock units
Vesting Period
Granted		8,689,481	464,632
Vesting in fourths on each anniversary of the grant date | Restricted stock units
Vesting Period
Granted		404,277	527,800

Share-Based Compensation - Summ

Share-Based Compensation - Summary of the RSU activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Number of RSUs Outstanding
Forfeited		(2.60)
Outstanding - December 31, 2023	746,445
Restricted stock units
Number of RSUs Outstanding
Outstanding - December 31, 2022	3,815,143
Granted	13,669,185	3,190,350
Forfeited		(86,700)
Exercised		(4,912,748)
Outstanding - December 31, 2023	12,484,880	3,815,143
Weighted average grant-date fair value per option
Outstanding - December 31, 2022	$ 2.75
Granted	0.92
Forfeited	0.96
Exercised	1.57
Outstanding - December 31, 2023	$ 1.23	$ 2.75

Share-Based Compensation - Empl

Share-Based Compensation - Employee Share Purchase Plan (Details)					12 Months Ended
	Aug. 14, 2023 shares	Feb. 21, 2023 shares	Aug. 12, 2022 shares	May 31, 2022 USD ($) shares	Dec. 31, 2023 USD ($) shares	Dec. 31, 2022 USD ($) shares
Share-Based Compensation
Aggregate of common shares to the investors | shares	4,150,000	5,000,000	37,978,680
Exploration and evaluation activities
Share-Based Compensation
Share based compensation expense					$ 200,000
General and administration expenses
Share-Based Compensation
Share based compensation expense						$ 67,000
Employee Share Purchase Plan
Share-Based Compensation
Number of share purchase under Employee Stock Purchase Plan (Note 15) (in shares) | shares					173,672
Employee Share Purchase Plan
Share-Based Compensation
Percentage of common stock shares outstanding				1%
Employee stock purchase plan offering period				24
Employee stock purchase plan, purchase period				4
Percentage of purchased share price				85%
Percentage of employees contribution limited to employees annual gross earnings				15%
Employee annual gross earnings not to exceed amount per year				$ 25,000
Employee purchases in any offering period cannot exceed common shares | shares				15,000
Percentage of employees purchases capped not to exceed total outstanding common shares				5%
Number of share purchase under Employee Stock Purchase Plan (Note 15) (in shares) | shares						117,929
Share based compensation expense					$ 47,000	$ 100,000
Employee Share Purchase Plan | Exploration and evaluation activities
Share-Based Compensation
Share based compensation expense					26,000	$ 35,000
Employee Share Purchase Plan | General and administration expenses
Share-Based Compensation
Share based compensation expense					$ 21,000
Employee Share Purchase Plan | Common Stock
Share-Based Compensation
Aggregate of common shares to the investors | shares					7,922,445
Issuance of common shares added to ESPP | shares				2,668,121

Loss per Share - Anti-dilutive

Loss per Share - Anti-dilutive common equivalent shares (Details) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Loss per Share
Total anti-dilutive common equivalent shares	202,072,578	201,286,201
Employee Stock Option
Loss per Share
Total anti-dilutive common equivalent shares	24,858,162	25,140,262
Outstanding RSUs
Loss per Share
Total anti-dilutive common equivalent shares	12,484,880	3,815,143
Outstanding shares under ESPP
Loss per Share
Total anti-dilutive common equivalent shares	8,802	12,212
Outstanding warrants
Loss per Share
Total anti-dilutive common equivalent shares	28,480,770	36,078,620
Outstanding Special Shares and options to purchase Special Shares
Loss per Share
Total anti-dilutive common equivalent shares	136,239,964	136,239,964

Financial Instruments - Schedul

Financial Instruments - Schedule of categories of financial instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022
Amortized cost.
Cash	$ 6,842	$ 22,548	$ 20,006	$ 28,390	$ 46,876
Receivables and Prepayments	1,978				2,726
Financial assets	8,820				49,602
Amortized cost.
Accounts payable and accrued liabilities	31,334	19,344	18,113	17,544	41,614
Royalty liability	14,000	14,000	14,000	14,000
Warrants liability	1,969	$ 2,197	$ 2,314	$ 1,528	983
Financial liabilities	$ 47,303				$ 42,597

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Aug. 14, 2023
Related Party Transactions
Other receivables	$ 467	$ 117	$ 300
ERAS Capital LLC
Related Party Transactions
Other receivables	10,000
SSCS Pte. Ltd | Related party | DeepGreen Engineering Pte. Ltd
Related Party Transactions
Consulting services	212	275
Amounts payable	17	17
SSCS Pte. Ltd | Related party | General and administration expenses | DeepGreen Engineering Pte. Ltd
Related Party Transactions
Consulting services	42	55
SSCS Pte. Ltd | Related party | Exploration and Evaluation | DeepGreen Engineering Pte. Ltd
Related Party Transactions
Consulting services	170	220
Ocean Renaissance LLC | Chief Ocean Scientist
Related Party Transactions
Consulting services	331	375
Amounts payable	25	0
Ocean Renaissance LLC | Chief Ocean Scientist | General and administration expenses
Related Party Transactions
Consulting services	182	187
Ocean Renaissance LLC | Chief Ocean Scientist | Exploration and Evaluation
Related Party Transactions
Consulting services	149	$ 188
Direct offering | Remaining commitment under first installment
Related Party Transactions
Remaining committed fund	1,000
Direct offering | Remaining commitment under second installment
Related Party Transactions
Remaining committed fund	$ 9,000

Commitments and Contingent Li_2

Commitments and Contingent Liabilities (Details) - USD ($) $ in Millions		60 Months Ended
	Dec. 23, 2022	Dec. 31, 2021	Dec. 31, 2019	May 25, 2012
Marawa Research and Exploration Limited
Commitments and Contingent Liabilities
Commitments plan submission period (in years)			5 years
Tonga Off shore Mining Limited
Commitments and Contingent Liabilities
Commitments plan submission period (in years)		5 years
Maximum estimated expenditure for five year period	$ 44
DeepGreen Engineering Pte Ltd
Commitments and Contingent Liabilities
Percentage of annual production committed to Glencore				50%

Segmented Information - Schedul

Segmented Information - Schedule of equipment (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) segment	Sep. 30, 2023 USD ($)	Jun. 30, 2023 USD ($)	Mar. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Segmented Information
Number of operating segment | segment	1
Equipment	$ 2,776	$ 2,078	$ 1,970	$ 1,997	$ 2,025
Nauru
Segmented Information
Equipment	1,128				1,154
Singapore
Segmented Information
Equipment	1,643				863
Tonga
Segmented Information
Equipment	$ 5				7
North America
Segmented Information
Equipment					$ 1

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Effective Tax Rate (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Taxes
Canadian Federal and Provincial income tax rates	26.68%	26.61%

Income Taxes - The income tax e

Income Taxes - The income tax expense at statutory rates for the Company (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2023	Jun. 30, 2023	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
Tax expense at statutory rates for the Company reconciled to the reported loss
Loss for the year, before taxes	$ (13,748)	$ (27,855)	$ (40,322)	$ (73,740)	$ (170,887)
Canadian Federal and Provincial income tax rates				26.68%	26.61%
Income tax recovery based on the above rates				$ (19,677)	$ (45,473)
Permanent differences				1,556	1,926
Effect of differences in future and foreign tax rates				14,038	36,903
Valuation allowance changes affecting the provision of income taxes				4,124	6,721
Total income taxes				$ 41	$ 77

Income Taxes - Additional infor

Income Taxes - Additional information (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Income Taxes
Uncertain tax position	$ 0

Income Taxes - The Company's de

Income Taxes - The Company's deferred income tax assets (liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022
Deferred Tax Assets
Non-capital losses	$ 21,195				$ 16,011
Investments	384				172
Equipment	260				79
Share issuance costs	496				218
Total deferred income tax assets	22,335				16,480
Valuation allowance	(22,335)				(16,480)
Deferred Tax Liability
Difference between the book value and the tax basis of the TOML exploration contract	10,675				10,675
Deferred tax liability recognized	$ 10,675	$ 10,675	$ 10,675	$ 10,675	$ 10,675

Income Taxes - Unused tax losse

Income Taxes - Unused tax losses and unused tax credits (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Income Taxes
Non-capital losses	$ 89,333	$ 67,409
Capital losses	2,856	1,273
Equipment	962	291
Share issuance costs	$ 1,860	$ 821

Income Taxes - Non-capital loss

Income Taxes - Non-capital loss (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Income Taxes
Loss carry-forwards	$ 89,333	$ 67,409
Canada
Income Taxes
Loss carry-forwards	29,791
Singapore
Income Taxes
Loss carry-forwards	20,567
United States
Income Taxes
Loss carry-forwards	6
Tonga
Income Taxes
Loss carry-forwards	38,969
2035 | United States
Income Taxes
Loss carry-forwards	2
2041 | Canada
Income Taxes
Loss carry-forwards	3,741
2042 | Canada
Income Taxes
Loss carry-forwards	13,707
2042 | United States
Income Taxes
Loss carry-forwards	1
2043 | Canada
Income Taxes
Loss carry-forwards	12,343
2043 | United States
Income Taxes
Loss carry-forwards	3
No expiry | Singapore
Income Taxes
Loss carry-forwards	20,567
No expiry | Tonga
Income Taxes
Loss carry-forwards	$ 38,969

Quarterly Financial Data (Una_3

Quarterly Financial Data (Unaudited) Restatement of Previously Issued Financial Statements (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2023	Jun. 30, 2023	Sep. 30, 2023	Dec. 31, 2023
Quarterly Financial Data (Unaudited) Restatement of Previously Issued Financial Statements
Net consideration received				$ 14,000
As Previously Reported
Quarterly Financial Data (Unaudited) Restatement of Previously Issued Financial Statements
Net consideration received				14,000
Gain on disposition of asset	$ 13,750	$ 13,750	$ 13,750	13,750
As Previously Reported | NORI Exploration Contract
Quarterly Financial Data (Unaudited) Restatement of Previously Issued Financial Statements
Amount of exploration licenses de-recognized				$ 250

Quarterly Financial Data (Una_4

Quarterly Financial Data (Unaudited) Restatement of Previously Issued Financial Statements - Condensed Consolidated Balance Sheet Information (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Sep. 30, 2023	Jul. 31, 2023	Jun. 30, 2023	Mar. 31, 2023	Mar. 21, 2023	Dec. 31, 2022	Dec. 31, 2021
Current
Cash	$ 6,842	$ 22,548		$ 20,006	$ 28,390		$ 46,876
Receivables and prepayments	1,978	5,325		1,637	3,230		2,726
Total current assets	8,820	27,873		21,643	31,620		49,602
Non-current
Exploration contracts	43,150	43,150		43,150	43,150		43,150
Equipment	2,776	2,078		1,970	1,997		2,025
Right-of-use asset	5,721	6,198	$ 6,515
Investment	8,429	8,525		8,644	8,781	$ 9,000
Total non-current assets	60,076	59,951		53,764	53,928		45,175
TOTAL ASSETS	68,896	87,824		75,407	85,548		94,777
Current
Accounts payable and accrued liabilities	31,334	19,344		18,113	17,544		41,614
Total current liabilities	31,334	19,344		18,113	17,544		41,614
Non-current
Deferred tax liability	10,675	10,675		10,675	10,675		10,675
Royalty liability	14,000	14,000		14,000	14,000
Warrants liability	1,969	2,197		2,314	1,528		983
TOTAL LIABILITIES	57,978	46,216		45,102	43,747		53,272
EQUITY
Common shares (unlimited shares, no par value - issued: 306,558,710 (December 31, 2022 - 266,812,131))	438,239	434,099		345,775	345,090		332,882
Additional paid in capital	122,797	124,168		188,722	186,796		184,960
Accumulated other comprehensive loss	(1,216)	(1,216)		(1,216)	(1,216)		(1,216)
Deficit	(548,902)	(515,443)		(502,976)	(488,869)		(475,121)
TOTAL EQUITY	10,918	41,608		30,305	41,801		41,505	$ 92,751
TOTAL LIABILITIES AND EQUITY	$ 68,896	87,824		75,407	85,548		$ 94,777
As Previously Reported
Current
Cash		22,548		20,006	28,390
Receivables and prepayments		5,325		1,637	3,230
Total current assets		27,873		21,643	31,620
Non-current
Exploration contracts		42,900		42,900	42,900
Equipment		2,078		1,970	1,997
Right-of-use asset		6,198
Investment		8,525		8,644	8,781
Total non-current assets		59,701		53,514	53,678
TOTAL ASSETS		87,574		75,157	85,298
Current
Accounts payable and accrued liabilities		19,344		18,113	17,544
Total current liabilities		19,344		18,113	17,544
Non-current
Deferred tax liability		10,675		10,675	10,675
Warrants liability		2,197		2,314	1,528
TOTAL LIABILITIES		32,216		31,102	29,747
EQUITY
Common shares (unlimited shares, no par value - issued: 306,558,710 (December 31, 2022 - 266,812,131))		434,099		345,775	345,090
Additional paid in capital		124,168		188,722	186,796
Accumulated other comprehensive loss		(1,216)		(1,216)	(1,216)
Deficit		(501,693)		(489,226)	(475,119)
TOTAL EQUITY		55,358		44,055	55,551
TOTAL LIABILITIES AND EQUITY		87,574		75,157	85,298
Restatement Adjustments
Non-current
Exploration contracts		250		250	250
Total non-current assets		250		250	250
TOTAL ASSETS		250		250	250
Non-current
Royalty liability		14,000		14,000	14,000
TOTAL LIABILITIES		14,000		14,000	14,000
EQUITY
Deficit		(13,750)		(13,750)	(13,750)
TOTAL EQUITY		(13,750)		(13,750)	(13,750)
TOTAL LIABILITIES AND EQUITY		$ 250		$ 250	$ 250

Quarterly Financial Data (Una_5

Quarterly Financial Data (Unaudited) Restatement of Previously Issued Financial Statements - Condensed Consolidated Balance Sheet Information (Parentheticals) (Details) - $ / shares	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022
Quarterly Financial Data (Unaudited) Restatement of Previously Issued Financial Statements
Common shares, par value	$ 0	$ 0	$ 0	$ 0	$ 0

Quarterly Financial Data (Una_6

Quarterly Financial Data (Unaudited) Restatement of Previously Issued Financial Statements - Condensed Consolidated Statements of Loss and Comprehensive Loss (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2023	Jun. 30, 2023	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
Operating expenses
Exploration and evaluation expenses	$ 7,169	$ 15,267	$ 23,172	$ 49,849	$ 144,599
General and administrative expenses	6,214	11,345	15,958	22,540	29,518
Operating loss	13,383	26,612	39,130	72,389	174,117
Other items
Equity-accounted investment loss	219	356	475
Change in fair value of warrants liability	545	1,331	1,214	986	(2,143)
Change in fair value of warrants	544
Foreign exchange loss	29	52	66	310	24
Interest income	(454)	(773)	(1,092)	(1,297)	(1,111)
Fees and interest on credit facility	27	277	529	781
Loss and comprehensive loss for the year, before tax	13,748	27,855	40,322	73,740	170,887
Tax expense				41	77
Loss and comprehensive loss for the year, after tax	$ 13,748	$ 27,855	$ 40,322	$ 73,781	$ 170,964
Loss per share - basic	$ 0.05	$ 0.10	$ 0.14	$ 0.26	$ 0.71
Loss per share - diluted	$ 0.05	$ 0.10	$ 0.14	$ 0.26	$ 0.71
Weighted average number of common shares outstanding - basic	272,029,603	276,702,050	282,745,892	288,643,700	239,867,019
Weighted average number of common shares outstanding - diluted	272,029,603	276,702,050	282,745,892	288,643,700	239,867,019
As Previously Reported
Operating expenses
Exploration and evaluation expenses	$ 7,169	$ 15,267	$ 23,172
General and administrative expenses	6,214	11,345	15,958
Operating loss	13,383	26,612	39,130
Other items
Equity-accounted investment loss	219	356	475
Gain on disposition of asset	(13,750)	(13,750)	(13,750)	$ (13,750)
Change in fair value of warrants liability	545	1,331	1,214
Change in fair value of warrants	544
Foreign exchange loss	29	52	66
Interest income	(454)	(773)	(1,092)
Fees and interest on credit facility	27	277	529
Loss and comprehensive loss for the year, before tax	(2)	14,105	26,572
Loss and comprehensive loss for the year, after tax	$ (2)	$ 14,105	$ 26,572
Loss per share - basic		$ 0.05	$ 0.09
Loss per share - diluted		$ 0.05	$ 0.09
Weighted average number of common shares outstanding - basic	272,029,603	276,702,050	282,745,892
Weighted average number of common shares outstanding - diluted	300,376,133	276,702,050	282,745,892
Restatement Adjustments
Other items
Gain on disposition of asset	$ 13,750	$ 13,750	$ 13,750
Loss and comprehensive loss for the year, before tax	13,750	13,750	13,750
Loss and comprehensive loss for the year, after tax	$ 13,750	$ 13,750	$ 13,750
Loss per share - basic	$ 0.05	$ 0.05	$ 0.05
Loss per share - diluted	$ 0.05	$ 0.05	$ 0.05
Weighted average number of common shares outstanding - basic	272,029,603	276,702,050	282,745,892
Weighted average number of common shares outstanding - diluted	272,029,603	276,702,050	282,745,892

Quarterly Financial Data (Una_7

Quarterly Financial Data (Unaudited) Restatement of Previously Issued Financial Statements - Condensed Consolidated Statements of Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended	5 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2023	Dec. 31, 2023	Jun. 30, 2023	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
Operating activities
Gain/(Loss) for the period	$ (13,748)		$ (27,855)	$ (40,322)	$ (73,781)	$ (170,964)
Items not affecting cash:
Amortization	88		175	262	360	418
Lease expense		$ 794		318	795
Share-based compensation and Expenses settled with equity	1,775		4,307	6,839	12,360	20,077
Expenses to be settled with share-based payments	15
Equity-accounted investment loss	219		356	475
Change in fair value of warrants liability	545		1,331	1,214	986	(2,143)
Vesting of Allseas Warrant						69,900
Unrealized foreign exchange movement	(20)		(17)	(24)	(51)	(53)
Changes in working capital:
Receivables and prepayments	(469)		1,123	(2,364)	748	960
Accounts payable and accrued liabilities	(11,877)		(11,277)	(10,757)	(1,561)	15,202
Net cash used in operating activities	(23,472)		(31,857)	(44,359)	(59,573)	(66,603)
Investing activities
Acquisition of equipment			(75)	(175)	(578)	(1,169)
Net cash used in investing activities			(75)	(175)	(578)	(1,169)
Financing activities
Proceeds from Low Carbon Royalties investment	5,000		5,000	5,000	5,000
Proceeds from Registered Direct Offering				15,723	15,923
Expenses paid for Registered Direct Offering				(779)	(1,182)
Proceeds from PIPE financing						30,399
Expenses paid for PIPE financing						(797)
Proceeds from employee share purchase plan			49	49	102	114
Proceeds from exercise of stock options				77	77	76
Proceeds from exercise of warrants by Allseas				116	116
Proceeds from issuance of shares			30	30	30
Taxes withheld and paid on share-based compensation						(70)
Net cash provided by financing activities	5,000		5,079	20,216	20,066	29,722
Decrease in cash	(18,472)		(26,853)	(24,318)	(40,085)	(38,050)
Impact of exchange rate changes on cash	20		17	24	51	53
Cash - beginning of year	46,876		46,876	46,876	46,876	84,873
Cash - beginning of year	46,842		46,842	46,842	46,842
Cash - end of year		$ 6,842			6,842	46,876
Cash - end of year	28,390		20,006	22,548		46,842
As Previously Reported
Operating activities
Gain/(Loss) for the period	2		(14,105)	(26,572)
Items not affecting cash:
Amortization	88		175	262
Lease expense				318
Share-based compensation and Expenses settled with equity	1,775		4,307	6,839
Expenses to be settled with share-based payments	15
Equity-accounted investment loss	219		356	475
Gain on disposition of asset	(13,750)		(13,750)	(13,750)	(13,750)
Change in fair value of warrants liability	545		1,331	1,214
Unrealized foreign exchange movement	(20)		(17)	(24)
Changes in working capital:
Receivables and prepayments	(469)		1,123	(2,364)
Accounts payable and accrued liabilities	(11,877)		(11,277)	(10,757)
Net cash used in operating activities	(23,472)		(31,857)	(44,359)
Investing activities
Cash received from investment in Low Carbon Royalties	5,000		5,000	5,000
Acquisition of equipment			(75)	(175)
Net cash used in investing activities	5,000		4,925	4,825
Financing activities
Proceeds from Registered Direct Offering				15,723
Expenses paid for Registered Direct Offering				(779)
Proceeds from employee share purchase plan			49	49
Proceeds from exercise of stock options				77
Proceeds from exercise of warrants by Allseas				116
Proceeds from issuance of shares			30	30
Net cash provided by financing activities			79	15,216
Decrease in cash	(18,472)		(26,853)	(24,318)
Impact of exchange rate changes on cash	20		17	24
Cash - beginning of year	46,842		46,842	46,842	$ 46,842
Cash - end of year	28,390		20,006	22,548		$ 46,842
Restatement Adjustments
Operating activities
Gain/(Loss) for the period	(13,750)		(13,750)	(13,750)
Items not affecting cash:
Gain on disposition of asset	13,750		13,750	13,750
Investing activities
Cash received from investment in Low Carbon Royalties	(5,000)		(5,000)	(5,000)
Net cash used in investing activities	(5,000)		(5,000)	(5,000)
Financing activities
Proceeds from Low Carbon Royalties investment	5,000		5,000	5,000
Net cash provided by financing activities	$ 5,000		$ 5,000	$ 5,000

Subsequent Events (Details)

Subsequent Events (Details) $ in Thousands	Mar. 22, 2024 USD ($) D	Mar. 22, 2023 USD ($) D	Sep. 09, 2021
Related party
Subsequent Events
Aggregate borrowed amount	$ 20,000,000
Subsequent event
Subsequent Events
Aggregate Subsidiaries	50,000,000
Allseas and affiliates | Line of credit | Related party
Subsequent Events
Aggregate borrowed amount		$ 25,000
Interest rate		4%
Interest paid in kind at maturity			5%
Number of days average considered for basis spread | D		180
Credit facility interest rate		4%
Allseas and affiliates | Line of credit | Subsequent event | Related party
Subsequent Events
Aggregate borrowed amount	$ 25,000,000
Interest rate	4%
Interest paid in kind at maturity	5%
Number of days average considered for basis spread | D	180
Credit facility interest rate	4%
Gerard Barron | Subsequent event | Related party
Subsequent Events
Aggregate borrowed amount	$ 10,000,000
ERAS Capital LLC | Subsequent event | Related party
Subsequent Events
Aggregate borrowed amount	$ 10,000,000

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2023	Jun. 30, 2023	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
Pay vs Performance Disclosure
Net Income (Loss)	$ (13,748)	$ (27,855)	$ (40,322)	$ (73,781)	$ (170,964)

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Dec. 31, 2023
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false