On June 11, 2026, Beijing Tongmei Xtal Technology Co., Ltd. ("Tongmei"), the subsidiary of AXT, Inc., a Delaware corporation, entered into a Long-term Supply Agreement (the "Agreement") with Nanjing Casela Technologies Corporation, Ltd. ("Casela"). The Agreement establishes an arrangement under which Tongmei reserves production capacity and raw-material allocation for, and grants supply priority to, Casela in exchange for Caela's binding commitment to purchase a fixed aggregate quantity of indium phosphide ("InP") wafer substrates from Tongmei during the period from January 1, 2027 through December 31, 2027.

During the year 2027, Casela is committed to purchase an agreed upon quantity of InP substrate wafers for a total price of RMB 173,000,000 (approximately US $25.4 million), to be delivered on a monthly schedule. Casela is required to pay 50% of the total purchase price as a prepayment within 15 business days after entry into the Agreement, with the remaining 50% due on or before December 31, 2026. Casela is required to purchase at least 80% of the fixed aggregate quantity of InP wafer substrates and if purchases fall below 80%, Casela must pay a cancellation fee for the unpurchased quantity.

To the extent Casela's demand during the term exceeds the committed quantity, Tongmei has agreed, subject to available capacity and on terms no less favorable than those offered to similarly situated customers, to prioritize Casela's excess demand. The pricing and other terms applicable to any such excess supplies will be set forth in a supplemental agreement.

Order cancellation, Casela's failure to take possession of goods made available for delivery, payment delinquency exceeding 30 days or failure to reach the 80% purchase threshold each constitute a fundamental breach, upon which Tongmei may, in its sole discretion, terminate the Agreement and retain all amounts previously paid by Caseal.

The Agreement contains customary provisions regarding delivery-schedule changes, pricing, product warranty, remedies for breach and dispute resolution.

The foregoing description does not purport to be complete and is qualified in its entirety by reference to the full text of the Long-term Supply Agreement, an English translation of which will be filed as an exhibit to our quarterly report on Form 10-Q for the period ended June 30, 2026.