By Mackenzie Tatananni

Pre-revenue nuclear start-up Oklo has taken another step toward commercializing its technology, clearing a key regulatory hurdle for its upcoming Aurora powerhouse at Idaho National Laboratory.

The stock rose 5.4% in premarket trading Thursday to $56.92.

The Energy Department approval relates to Aurora's preliminary documented safety analysis, a review of the reactor's safety controls, design, and hazard management. CEO Jacob DeWitte described the clearance as an "important milestone" and a foundation for future deployments.

Oklo is one of nearly a dozen companies selected for a federal pilot program in 2025. The initiative is on a tight schedule, aiming to have at least three test reactors running at U.S. national laboratories by the start of next month.

Earlier this week, the Energy Department confirmed that a design from rival Antares Nuclear will be the first of several reactors to go critical by the July 4 deadline.

Aurora is the first of Oklo's planned powerhouses. It will run on recovered fuel from the Experimental Breeder Reactor-II, which was shut down in 1994 following a government policy pivot and subsequent congressional defunding.

Oklo is building its own fuel fabrication site on the grounds of Idaho National Laboratory. The start-up is exploring ways to use plutonium as a temporary "bridge fuel" while the U.S. builds out domestic supply chains for traditional fuels like high-assay low-enriched uranium.

Write to Mackenzie Tatananni at mackenzie.tatananni@barrons.com

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June 11, 2026 08:11 ET (12:11 GMT)

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