AI Data Center Sparks 'Nuclear Theme Stocks'... Market Cap Soars by 1.3 Trillion Won in a Day

On April 13, OKLO Inc. (NYSE: OKLO) saw its shares surge 8.23% on the New York Stock Exchange, closing at $54.40, with trading volume topping 4.82 million shares. Its market capitalization expanded to roughly $9.4 billion (about ₩14 trillion), adding approximately $850 million (around ₩1.3 trillion) in a single day. The rally reflects heightened investor interest driven by expectations for power demand from AI data centers and the momentum behind next-generation small modular reactors.

In recent days, OKLO has emerged as a notably volatile stock, logging daily trading volumes in the hundreds of millions of dollars amid an improving regulatory environment and enthusiasm for so-called “AI nuclear” technology. The company is in ongoing pre-application discussions with the U.S. Nuclear Regulatory Commission (NRC) as it prepares to submit the license application for its first commercial Aurora microreactor. In its March update on projected 2025 results and business outlook, OKLO identified data-center and defense markets as its core growth pillars.

OKLO is a U.S. nuclear startup developing fast-neutron small modular reactors, spent-fuel recycling, and medical and industrial isotope production. It went public via a SPAC merger in 2024, marking it as an early-stage entrant in the nuclear power sector. Notably, OpenAI co-founder Sam Altman once served as the company’s largest shareholder and board chairman. OKLO is frequently cited as a textbook “high-risk, high-reward” theme stock offering a potential solution to power shortages in the AI era.