Oklo Achieves First Test Reactor Fission, Shifting SMR Investor Focus to Permitting and Fuel Supply
The Sam Altman-backed firm demonstrated working reactor technology on August 6, closing a technical gap that weighed against its near-$24 billion peak valuation.
Oklo split its first atoms in a test reactor, Canary Media reported on Thursday (2026-08-06), a concrete engineering milestone the Sam Altman-backed firm had not achieved in any of its reactors during its years as a publicly traded company.5
The milestone registers against the company's own valuation history. Oklo's market cap had risen to nearly $24 billion at its peak while the reactor had yet to produce fission, a spread that placed the stock firmly in the demand-anticipation category rather than that of an operating business. Test fission changes that characterization without yet bringing revenue, and without resolving the regulatory sequence between a working test unit and a licensed commercial plant.5
The Global X Uranium ETF (ticker URA) traded at $45.20 as of Thursday (2026-08-13), up 0.22% on the session. Within the fund, Oklo carried a 4.3% weighting, NuScale Power a 4.5% weighting, and Centrus Energy a 5.8% position. Centrus holds regulatory approval to produce high-assay low-enriched uranium (HALEU), the enriched fuel that next-generation SMRs require for operation, giving it a distinct supply chain role in the sector.6
HALEU supply is a concrete production bottleneck. The National Defense Authorization Act of 2024 directed the Department of Energy to support commercial HALEU enrichment, and Centrus secured a $900 million DOE contract in January 2026 to develop that capacity.3
That supply chain linkage already drove one notable equity event. When Oklo and Centrus disclosed a uranium supply agreement in June 2026, Oklo shares gained 4% on Thursday (2026-06-18), Centrus surged more than 12%, uranium miner Energy Fuels climbed more than 8%, and SMR rivals NuScale Power and NANO Nuclear Energy rose 13% and 11% respectively.3 Nuclear equities trade as a tight cluster; a single supply announcement can move the entire peer group simultaneously.
The demand case underpinning those valuations centers on AI infrastructure. The Department of Energy projects that U.S. data centers alone will add roughly 20 gigawatts of new electricity load by 2030.2 Oklo's Aurora reactor targets that market and industrial facilities and remote operations. A fraction of projected data center demand captured by SMRs could translate into a large number of commercial deployments, each generating revenue that currently exists only in forecasts.2,1
Still, Oklo's stock was trailing broader market performance in 2026 while carrying a roughly $12 billion market capitalization.1 That figure sits well below the near-$24 billion peak and reflects the expansion of Oklo's stated ambitions into nuclear waste recycling, fuel fabrication, and medical isotope production, without corresponding commercial revenue across any of those lines.5
Terra Innovatum's addition to the Solactive Global Uranium and Nuclear Components Total Return Index, tracked by the Global X Uranium ETF, illustrates passive index methodology broadening to absorb smaller nuclear operators.4 Index inclusion channels passive capital flows into the sector independent of individual project progress, a dynamic that can support prices even when operating milestones remain distant.
Oklo's NRC construction permit application for a commercial unit is the cleaner forward indicator than the test reactor milestone. Test fission establishes engineering feasibility; building and operating on U.S. soil requires a separate regulatory proceeding, and no confirmed timeline for that approval appears in published reporting on the company.5 Centrus's ability to scale HALEU production fast enough to supply first commercial deployments is the parallel supply-side question the June 2026 equity surge showed traders are already pricing.3