Lightbridge completed the final design review of its ATR irradiation experiment in June 2025 and loaded enriched uranium-zirconium alloy samples into INL’s Advanced Test Reactor in November, initiating FAST irradiation at 26–30% enrichment. The company expects initial sample discharge in April–May with post-irradiation examination to assess burnup, structural integrity, and thermal conductivity later this year.

In fiscal 2025 Lightbridge presented three TopFuel papers demonstrating safety margins under locked rotor accidents, superior transient simulation performance compared to UO2, and accurate modeling of its co-extrusion fabrication process, strengthening its safety case and design validation for future regulatory engagement.

Lightbridge ended the year with $201.9 million in cash and cash equivalents, up from $40 million a year earlier, after raising $176 million via its at-the-market equity program. The debt-free balance sheet and $3.6 million in interest income provide resources to fund continued development and regulatory efforts.

The company plans continued irradiation tests and post-irradiation exams, refinement of its Phenomena Identification and Ranking Table analysis, and advancement of co-extrusion fabrication for rodlets and full-length rods. Formal engagement with regulators and site selection for an expandable fuel facility are slated for the coming two to three years.