X-energy Raises $1B in Largest-Ever Nuclear IPO, Closes Up 27% on Nasdaq Debut (April 2026)

Nuclear startup X-energy raised $1.017 billion in its initial public offering on April 23, 2026, pricing 44,254,659 Class A shares at $23 — 21% above the marketed range — and began trading on the Nasdaq Global Select Market under the ticker XE the next morning. The Amazon-backed small modular reactor (SMR) developer closed its first day up roughly 27% at $29.20 a share, valuing the company near $11.5 billion and making this the largest nuclear public equity offering on record.

What Happened

According to X-energy's official pricing release, the Rockville, Maryland company sold 44.25 million Class A shares at $23 per share, with a 30-day overallotment option for up to an additional 6.64 million shares. The deal was led by J.P. Morgan, Morgan Stanley, Jefferies, and Moelis & Company. Trading opened at $29.20 on Friday, April 24, 2026, and the offering is expected to formally close on April 27, 2026.

CNBC reported the IPO was 15× oversubscribed, with shares jumping as much as 36% intraday before settling 27% above offer. TechCrunch and Bloomberg both pegged the post-IPO market cap between $11.5 billion and $11.9 billion depending on close.

Key Details

• Reactor design: The flagship Xe-100 is an 80-megawatt high-temperature gas-cooled reactor that uses helium gas flowing over billiard-ball-sized "pebbles" packed with BB-sized TRISO fuel pellets. Four units typically deploy together as a 320-MW plant.
• Anchor customers: Amazon has agreed to purchase up to 5 GW of nuclear power by 2039, Dow has signed for an Xe-100 plant to provide heat and electricity to a Texas chemical facility, and U.K. utility Centrica is a third disclosed offtaker.
• Cap table: Amazon, alongside Ares Management and Founder Kamal Ghaffarian's IBC Group, are pre-IPO backers. The company was founded in 2009.
• Use of proceeds: Roughly $1 billion will fund TRISO fuel manufacturing, NRC licensing for the Xe-100, and the first commercial deployment with Dow.
• Comparable benchmark: Rival SMR developer Oklo, which IPO'd in 2024 via SPAC, has since rallied past a $20B market cap on similar AI-power demand themes.

What Developers and Users Are Saying

Coverage has skewed bullish but not uncritical. The Next Web framed the debut as "the AI data-center power thesis playing out in equity markets," noting that hyperscalers signing decade-long power purchase agreements have de-risked SMR developers more than any government program. ESG Today highlighted that X-energy now has the balance sheet to actually break ground on a U.S. SMR rather than remain a paper-design company.

Skeptics on financial Twitter and Reddit's r/investing pointed out that no Xe-100 has yet operated commercially, NRC certification is still pending, and the company has $0 in product revenue. The closest historical analog — NuScale, which lost its UAMPS deal in 2023 — looms large for nuclear bears. Several commenters argued the 27% pop reflects scarcity of pure-play AI-power equities more than X-energy's specific milestones.

What This Means for Developers and Operators

For data-center operators planning AI capacity beyond 2030, X-energy's IPO is the clearest signal yet that long-dated nuclear PPAs are now financeable. The Xe-100's modular construction, factory-built components, and inherent walk-away safety make it a credible answer to the question every hyperscaler is now asking: where will the next 50 GW of clean baseload come from? Expect more SMR developers — TerraPower, Kairos Power, Last Energy — to test public markets in the next 12–18 months. For software and infrastructure teams: budget for power as a real constraint on AI capacity expansion in 2027 and beyond.

What's Next

X-energy says proceeds will accelerate construction of its TX-1 TRISO fuel facility in Oak Ridge, Tennessee, and the first Xe-100 deployment with Dow at Seadrift, Texas, with target initial operation in 2030. The 30-day overallotment, if fully exercised, would push total proceeds past $1.17 billion. The company will report its first quarterly earnings as a public company in August 2026.

Sources

• X-energy press release — Official IPO pricing announcement, April 23, 2026.
• TechCrunch — Coverage of the data-center thesis driving demand.
• CNBC — First-day trading and oversubscription details.
• Bloomberg / BNN — Post-debut valuation and investor commentary.
• ESG Today — Customer disclosures and balance-sheet implications.
• The Next Web — Synthesis of the AI-power thesis.