6. Investments

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Investments in Non-consolidated Entities and Non-marketable Securities

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Non-marketable Securities

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Our investment in non-marketable securities was $12.3 million and $12.8 million as of September 30, 2026 and December 31, 2025, respectively, of which $10.2 million is expected to be redeemed within the next 12 months and is included in prepaid expenses, tax credits, and other current assets on the Company’s unaudited interim condensed consolidated balance sheets.

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Equity Method Investments

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As of September 30, 2026 and December 31, 2025, the Company accounted for the following investments in the investee’s common stock under the equity method, which are included in the investments in non-consolidated entities and non-marketable securities on the unaudited interim condensed consolidated balance sheets (amounts in thousands):

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During the three months ended September 30, 2026, the Company made no contributions to AccionaPlug S.L. and Clean H2 Infra Fund. During the three months ended September 30, 2025, the Company contributed approximately $0.3 million and $0 to AccionaPlug S.L. and Clean H2 Infra Fund, respectively.

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During the nine months ended September 30, 2026, the Company contributed approximately $0.6 million and $6.0 million to AccionaPlug S.L. and Clean H2 Infra Fund, respectively. During the nine months ended September 30, 2025, the Company contributed approximately $1.1 million and $0 to AccionaPlug S.L. and Clean H2 Infra Fund, respectively.

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As of September 30, 2026, the Company’s capital commitment related to its equity method investments was $1.2 million, all of which is expected to be paid during the fourth quarter of 2026.