Amazon-backed nuclear startup X-Energy raises $1.02 billion in IPO


Amazon-backed nuclear startup X-Energy raises $1.02 billion in IPO

X-Energy sold 44.3 million Class A shares at $23 each, above the $16–$19 marketed range, and began trading on Nasdaq under the ticker XE on 24 April. The company has $1.8 billion in prior private capital, a $500 million Amazon-led Series C-1, and a binding commitment from Amazon to buy up to 5 gigawatts of nuclear power by 2039.


X-Energy, the Rockville, Maryland-based small modular reactor developer backed by Amazon, raised $1.02 billion in its initial public offering on 23 April 2026, pricing its upsized offering at $23 per share, 21% above the top of its marketed range of $16 to $19. \

The company sold 44.3 million Class A shares and began trading on the Nasdaq Global Select Market under the ticker XE on 24 April.

The IPO is the largest public market debut by an advanced nuclear company to date and arrives at a moment when electricity demand from AI data centres, manufacturing reshoring, and electrification has made reliable, carbon-free baseload power one of the most commercially urgent infrastructure problems in the United States.

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The pricing tells its own story. X-Energy launched its investor roadshow with a target range of $16 to $19, implying gross proceeds of up to $814 million.

The final price of $23 represents a 21% premium above the top of that range and total proceeds of $1.02 billion, a figure that required an upsized offering, more shares sold than originally planned. ARK Investment Management, Cathie Wood’s thematic fund, indicated interest in purchasing up to $105 million worth of shares at the IPO price.

The oversubscription and above-range pricing reflect investor conviction in the nuclear renaissance narrative, which has been building momentum since major technology companies began making long-dated nuclear power purchase agreements.

Amazon’s role in X-Energy’s story is central. The company led X-Energy’s $500 million Series C-1 round and has pledged to purchase up to 5 gigawatts of nuclear power from the company by 2039, a commitment that functions as both a revenue anchor and a validation signal for the underlying technology.

For context, 5 gigawatts is roughly the output of five large conventional nuclear power plants, or approximately equivalent to the electricity demand of a mid-sized American city.

Amazon’s nuclear bet is driven by the arithmetic of AI: its data centres require enormous, predictable quantities of electricity that renewable sources, absent storage, cannot provide around the clock.

Nuclear power, specifically the small modular reactors that X-Energy is developing, offers carbon-free baseload generation in a physically compact footprint.

X-Energy’s core technology is the Xe-100, a pebble bed modular reactor design that the company has been developing since its founding in 2009 by Kamal Ghaffarian. The Xe-100 is designed to produce approximately 80 megawatts of thermal power per unit, with four units typically deployed together as a 320 MW plant.

The pebble bed design uses uranium-coated fuel spheres rather than conventional fuel rods, which the company says provides inherent safety properties: the reaction slows down naturally if the reactor overheats, without requiring active cooling intervention.

The NRC has been engaged in pre-application review of the Xe-100 design. X-Energy also manufactures advanced nuclear fuel, a vertically integrated capability that reduces supply chain dependency.

The IPO crowns a private capital raise of more than $1.8 billion, according to PitchBook, across multiple rounds that included strategic investors alongside Amazon.

Founder and chairman Kamal Ghaffarian retains control of 61% of the Class B shares of the combined company, giving him voting control despite the public float. Ares Management Corp holds a significant stake.

The proceeds of the IPO will be used to accelerate reactor development, scale up fuel fabrication capacity, and fund the commercialisation of the Xe-100 towards its first deployment, which X-Energy has targeted for the early 2030s.

The broader context is the most significant element. X-Energy’s IPO is not an isolated event. Microsoft has agreed to restart Unit 1 of Three Mile Island with Constellation Energy to supply its data centres. Google has signed agreements with Kairos Power for SMR capacity.

Meta and Oracle have also made nuclear power commitments. The pattern is consistent: hyperscalers with rapidly growing AI compute footprints are making long-dated, utility-scale power purchase agreements with nuclear developers because no other technology can reliably deliver carbon-free baseload electricity at the scale and predictability that AI infrastructure requires.

Vikram Bagri, an analyst who published a client note on 17 April, said the IPO launch “suggests continued appetite among investors for small modular reactors,”, which is, on the evidence of a $1.02 billion above-range debut, something of an understatement.

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