CENTURY ALUMINUM CO

13. Shareholders' Equity

Common Stock

As of September 30, 2025 and December 31, 2024, we had 195,000,000 shares of common stock, $0.01 par value per share, authorized under our Restated Certificate of Incorporation, of which 100,528,490 shares were issued and 93,341,969 shares were outstanding at September 30, 2025, and 100,475,086 were issued and 93,288,565 shares were outstanding at December 31, 2024.

The rights, preferences and privileges of holders of our common stock are subject to, and may be adversely affected by, the rights of the holders of shares of any series of our preferred stock which are currently outstanding, including our Series A Convertible Preferred Stock, or which we may designate and issue in the future.

Preferred Stock

As of September 30, 2025 and December 31, 2024, we had 5,000,000 shares of preferred stock, $0.01 par value per share, authorized under our Restated Certificate of Incorporation. Our Board of Directors may issue preferred stock in one or more series and determine for each series the dividend rights, conversion rights, voting rights, redemption rights, liquidating preferences, sinking fund terms and the number of shares constituting that series, as well as the designation thereof. Depending upon the terms of preferred stock established by our Board of Directors, any or all of the preferred stock could have preference over the common stock with respect to dividends and other distributions and upon the liquidation of Century. In addition, issuance of any shares of preferred stock with voting powers may dilute the voting power of the outstanding common stock.

Series A Convertible Preferred Stock

In 2008, we issued 160,000 shares of our Series A Convertible Preferred Stock. At September 30, 2025 and December 31, 2024,49,486 and 49,715 shares of Series A Convertible Preferred Stock were outstanding, respectively. Glencore holds all of the issued and outstanding Series A Convertible Preferred Stock.

The issuance of common stock under our stock incentive programs, debt exchange transactions and any stock offering that excludes Glencore participation triggers anti-dilution provisions of the preferred stock agreement and results in the automatic conversion of Series A Convertible Preferred Stock shares into shares of common stock. The conversion of preferred to common shares is 100 shares of common stock for each share of preferred stock. Our Series A Convertible Preferred Stock has a par value of $0.01 per share.

Stock Repurchase Program

In 2011, our Board of Directors authorized a $60.0 million common stock repurchase program and during the first quarter of 2015, our Board of Directors increased the size of the program by $70.0 million. Under the program, Century is authorized to repurchase up to $130.0 million of our outstanding shares of common stock, from time to time, on the open market at prevailing market prices, in block trades or otherwise. The timing and amount of any shares repurchased will be determined by our management based on its evaluation of market conditions, the trading price of our common stock and other factors. The stock repurchase program may be suspended or discontinued at any time.

Shares of common stock repurchased are recorded at cost as treasury stock and result in a reduction of shareholders’ equity in the Consolidated Balance Sheets. From time to time, treasury shares may be reissued as contributions to our employee benefit plans and for the conversion of convertible preferred stock. When shares are reissued, we use an average cost method for determining cost. The difference between the cost of the shares and the reissuance price is added to or deducted from additional paid-in capital.

Through September 30, 2025 we repurchased 7,186,521 shares of common stock for an aggregate purchase price of $86.3 million. We have madeno repurchases since April 2015 and have approximately $43.7 million remaining under the repurchase program authorization as of September 30, 2025.

14. Business Segments

The Company is a producer of primary aluminum and alumina. The Company has organized itself, including management personnel and systems, financial processes, operational execution, governance and risk oversight, regulatory compliance, and every other aspect of the Company’s operations, to assess and manage the business on a holistic basis, from mine to metal, which tracks the upstream manufacturing process for aluminum. To better reflect this operational and organizational approach, and to further enhance the reporting of its financial and operating results, beginning with the quarter ended March 31, 2025, the Company’s Chief Executive Officer and Chief Operating Decision Maker ("CODM") regularly receives and reviews financial information at the consolidated level to evaluate business performance and make operating decisions. The CODM uses the U.S. GAAP measure of consolidated Net Income to develop forecasting, t evaluate the Company’s overall profitability and financial performance and to make key operating decisions, such as the allocation of resources.

Given the change described above, the Company has determined that neither itsthree smelters nor Jamalco’s mining and refining operations meet the definition of operating segments. As a result, the Company has determined that the Company has onlyone operating and onlyone reportable segment, and it is managed on a consolidated basis. In accordance with ASC 280-10-50-34, the corresponding information for earlier periods is recast in the tables below to conform with the updated presentation.

Segment assets are reported on our Consolidated Balance Sheets as Total assets. Our Consolidated Statements of Cash Flows presents Depreciation, depletion and amortization expense and includes the measure of capital expenditures as Purchase of property, plant and equipment.

The following table presents information about the Company's single segment for the three and nine months ended September 30, 2025 and 2024.

(1)Indicates a component of Cost of goods sold.

(2)Includes raw materials, labor, energy, freight costs, FIFO inventory adjustments and other direct cost of goods sold.

(3)Advanced production credit related to Section 45X of the IRA.

(4)Includes inventory revaluation to lower of cost or net realizable value and changes in inventory reserve.

(5)Represents the depreciation expenses and expenses related to leased assets that are directly related to the cost of goods sold.

15. Variable Interest Entity

The Company consolidates Jamalco, a bauxite mining and alumina refinery in Jamaica, under the variable interest entity ("VIE") model. Jamalco lacks sufficient equity investment at risk in accordance with relevant guidance. Based on its purpose and design, Jamalco is expected to require additional subordinated financial support, such as those in the form of equity contributions or other forms of subordinated financing, which the Company expects would require parent guarantees.

The Company owns a 55% ownership interest in Jamalco through its wholly-owned subsidiary, GAJL, which serves as the managing partner. The Company is responsible for funding 55% of Jamalco's operating costs and capital requirements and is not obligated to provide additional financial support beyond its equity interest. Upon acquisition, the Company made an immediate equity contribution to Jamalco and has provided subsequent financing of costs for Jamalco to perform its activities in the ordinary course of business.

The Company obtains direct ownership of our 55% share of Jamalco’s outputs and purchases the remaining 45% of the output from the Government of Jamaica. Through direct ownership and purchase,100% of Jamalco’s output is either retained and utilized in the Company’s business operations or sold by the Company. The Company’s consolidated statement of cash flows reflects 100% of cash flows related to the Jamalco operations. The Company receives cash proceeds from the Government of Jamaica for its 45% interest of the Jamalco operating costs and capital requirements.

Although our partner has certain participating rights over some decisions of the entity, the Company has power over the majority of key activities at Jamalco that significantly affect its economic performance over which the counterparty does not have such participating rights; therefore, the Company is the primary beneficiary of the VIE.

The table below shows the carrying amounts and classification of the consolidated VIE's assets and liabilities included in the Consolidated Balance Sheets as of September 30, 2025 and December 31, 2024.

16. Subsequent Events

Repayment of Grundartangi Casthouse Facility

On October 27, 2025, we repaid all $116.4 million in outstanding borrowings and $1.9 million in interest under the Grundartangi Casthouse Facility.

FORWARD-LOOKING STATEMENTS

This quarterly report includes "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995, which are subject to the "safe harbor" created by section 27A of the Securities Act of 1933, as amended, and section 21E of the Securities Exchange Act of 1934 (the "Exchange Act"), as amended. Forward-looking statements are statements about future events and are based on our current expectations. These forward-looking statements may be identified by the words "believe," "expect," "hope," "target," "anticipate," "intend," "plan," "seek," "estimate," "potential," "project," "scheduled," "forecast" or words of similar meaning, or future or conditional verbs such as "will," "would," "should," "could," "might," or "may."

Forward-looking statements in this quarterly report and in our other reports filed with the Securities and Exchange Commission (the "SEC"), for example, may include, but are not limited to, statements regarding:

•Our assessment of global and local financial and economic conditions;

•Our assessment of the alum inum market and aluminum prices (including premiums);

•Our assessment of prices of our key raw materials and supply and availability of those key raw materials, including alumina, coke, pitch and aluminum fluoride;

•Our assessment of power prices and availability, including any potential curtailments or other disruptions in the supply of power;

•The impact of the wars in Ukraine and in the Middle East, including anysanctions and export controls targeting Russia and businesses or individuals tied to Russia;

•The future financial and operating performance of the Company and its subsidiaries;

•Our ability to successfully manage market risk and to control or reduce costs;

•Our plans and expectations with respect to future operations of the Company and its subsidiaries, including any plans and expectations to curtail or restart production, including the expected impact of any such actions on our future financial and operating performance;

•Our plans and expectations with regards to any restart of curtailed production at Mt. Holly including the timing, costs and benefits associated with restarting curtailed production;

•Any future impact of the equipment failure at Grundartangi and related events on our financial and operating performance, including our expectations as to timing for bringing the facility to 100% capacity with respect to insurance coverage relating thereto;

•Our plans with regards to the future of our Hawesville smelter;

•Our ability to successfully obtain and/or retain competitive power arrangements for our operations, including securing necessary power arrangements for the greenfield project;

•The impact of Section 232 and 301 and other trade actions, including tariffs or other trade remedies, the extent to which any such remedies may be changed, including through exclusions or exemptions, and the duration of any trade remedy;

•The impact of any new or changed law or regulation, including, without limitation, sanctions or other similar remedies or restrictions or any changes in interpretation of existing laws or regulations;

•Our anticipated tax liabilities, benefits or refunds including the realization of U.S. and certain foreign deferred tax assets and liabilities;

•Our ability to qualify for and realize potential tax benefits under the Inflation Reduction Act of 2022 and the anticipated amounts of such benefits;

•Our expectations regarding the availability of the $500 million DOE funding to our new smelter project, including our ability to raise additional capital through additional grants, incentives, subsidized loans and other debt and equity funding to support construction of a new aluminum smelter and our ability to successfully complete our new smelter project;

•Our ability to access existing or future financing arrangements and the terms of any such future financing arrangements;

•Our ability to repay or refinance debt in the future;

•Our ability to recover losses from our insurance;

•Our assessment and estimates of our pension and other postretirement liabilities, legal and environmental liabilities and other contingent liabilities;

•Our assessment of any future tax audits and expected outcomes;

•Negotiations with current labor unions or future representation by a union of our employees;

•Our assessment of any information technology-related risks, including the risk from cyberattacks or other data security breaches;

•Our plans and expectations regarding potential M&A and joint venture activity including our ability to consummate such transactions and our assessments of certain risks associated with the same, including, for example, unforeseen costs and expenses associated with unidentified liabilities, and difficulties integrating an acquired asset into our existing operations; and

•Our future business objectives, plans, strategies and initiatives, including our competitive position and prospects.

Where we express an expectation or belief as to future events or results, such expectation or belief is expressed in good faith and believed to have a reasonable basis. However, our forward-looking statements are based on current expectations and assumptions that are subject to risks and uncertainties which may cause actual results to differ materially from future results expressed, projected or implied by those forward-looking statements. Important factors that could cause actual results and events to differ from those described in such forward-looking statements can be found in the risk factors and forward-looking statements cautionary language contained in Item 1A. Risk Factors in our Annual Report on Form 10-K, quarterly reports on Form 10-Q and in other filings made with the SEC. Although we have attempted to identify those material factors that could cause actual results or events to differ from those described in such forward-looking statements, there may be other factors that could cause actual results or events to differ from those anticipated, estimated or intended. Many of these factors are beyond our ability to control or predict. Given these uncertainties, the reader is cautioned not to place undue reliance on our forward-looking statements. We undertake no obligation to update or revise publicly any forward-looking statements, whether as a result of new information, future events, or otherwise.