We received stock of Standard Lithium under the terms of arrangements whereby Standard Lithium has the right to explore for, produce and extract lithium in our Arkansas leases and other additional potential resources in the Mojave region of California. The stock component of consideration received from Standard Lithium was initially recorded as unearned income based on the quoted market price at the time the stock was received, then recognized in income over the contract term. Changes in the value of stock are recorded in other (income) expense, net in our consolidated statements of operations.

We also hold investments in convertible notes, common units and preferred units issued by two privately-held companies. These convertible notes, common units and preferred units are not publicly traded and may not be offered, sold, transferred or pledged until such common units are registered pursuant to an effective registration statement or pursuant to an exemption from registration. Our exposure to potential losses is limited to our investments, including capitalized and accrued interest associated with the convertible notes.

At September 30, 2026, our available-for-sale debt securities consisted of U.S. Treasury bills with an amortized cost of $74.9 million and a fair value of $74.8 million. These securities were purchased with a portion of the net proceeds from our June 2026 common stock offering. Of the fair value, $33.1 million is included in cash and cash equivalents and $41.7 million in short-term investments. All of the securities mature within one year. Gross unrealized gains and losses were each less than $0.1 million, and each security in an unrealized loss position had been in that position for less than 12 months. The unrealized losses result from changes in interest rates, not credit quality. The securities are obligations of the U.S. government. We do not intend to sell them, and it is not more likely than not that we will be required to sell them before recovery of their amortized cost basis. Accordingly, no allowance for credit losses has been recorded. See Note 7 - “Fair Value Measurements.”