Nuclear energy stocks fell sharply on Thursday as investors rotated out of AI-linked trades and demanded evidence that advanced reactor companies can meet their ambitious timelines.
Oklo Inc. (NASDAQ: OKLO), X-Energy Inc. (NYSE: XE), NuScale Power Corp. (NYSE: SMR), Nano Nuclear Energy Inc. (NYSE: NNE), and Uranium Energy Corp. (NYSE: UEC) each lost between 8% and 9% in Thursday’s session.
The selloff adds to a difficult year for nuclear energy names, which have dipped significantly since the start of 2026 despite long-term enthusiasm for the sector.
Truist analyst Christopher Souther recently initiated coverage of Oklo, NuScale Power, and Nano Nuclear, assigning “Hold” ratings to all three companies.
Souther noted that the sector’s “first-of-a-kind projects” are now moving from concept to execution, and that investors are increasingly looking for proof that these companies can build, license, and deploy reactors on schedule.
Valuations remain a central concern, with XE stock trading at a trailing enterprise value to sales multiple of 48.4x, while SMR’s figure stood at a striking 91.2x.
The VanEck Uranium and Nuclear ETF (NLR), which tracks global companies in uranium mining and nuclear power generation, surged over 50% in 2025 but has lost about 15% of its value so far in 2026.
Everett Randle, General Partner at Benchmark, told Technology Business Programming Network on Thursday that investor enthusiasm has created a self-reinforcing cycle of markups across AI, defense, and nuclear energy.
“There’s this sense that we all know AI is going to change the world in so many ways. We all know that space is big, defense is big, nuclear energy is big. All these things are big. Therefore, more and more money goes into these things and they just keep getting marked up,” Randle said.
Randle also drew a direct comparison to the market conditions of late 2021, warning that the current sense of inevitability among investors mirrors a period that preceded a sharp correction driven by rising interest rates.
“The last time I felt like investors had this much of a sense of inevitability saying, ‘Yes, it’s expensive, it’s going to get marked up in six months so therefore we should do it,’ was the summer and fall of 2021. We all know how that ended up,” he added.
Standard Nuclear (STDN), a Tennessee-based manufacturer of uranium fuel pellets, debuted on Wednesday, raising $150 million at a valuation of approximately $2 billion, offering a fresh gauge of market sentiment toward the sector.
However, shares of Standard Nuclear opened below its $15 offering price and are currently trading approximately 16.7% lower, signaling a cautious reception from the market.
Standard Nuclear, which acquired assets from a bankrupt nuclear firm in 2024, is already generating revenue and has been selected as a partner in the U.S. Department of Energy’s nuclear acceleration program, though its long-term growth remains tied to the success of advanced reactor developers.
Not all investors are retreating from the sector, as Cathie Wood’s Ark Investment Management has continued to accumulate shares in nuclear names even as prices decline.
On Thursday alone, Ark purchased 507,347 shares of XE for approximately $7.64 million, according to the firm’s trade notifications, underscoring its conviction in the space.
Retail sentiment on Stocktwits was mixed, with OKLO and UEC rated “neutral,” SMR and XE rated “bearish,” and NNE remaining in “bullish” territory at the time of publication.
One Stocktwits user noted that days like Thursday should remind traders of “fear and greed,” adding that “volatility is chaos and anarchy rules, but solvency is survival and cash is king.”
