Deep Fission hunts Nasdaq IPO after “public” déjà vu

Nuclear startup Deep Fission says it’s going public again, this time with a Nasdaq IPO seeking $157 million at $24 to $26 a share. The company previously completed a reverse merger meant to take it public—yet its stock never actually traded, leaving its first

When a nuclear startup announces it’s going public “again,” it’s supposed to feel like momentum. For Deep Fission, this feels more like a rewind.

This week. the company said it was seeking investor support to build subterranean reactors to power AI data centers—through a Nasdaq IPO that it expects to raise $157 million at $24 to $26 a share. The question that won’t go away is simple: if it’s going public for the second time. what happened the first time?.

Last September. Deep Fission said it had already gone public via a reverse merger with Surfside Acquisition. a Delaware shell company. The structure was designed to get Deep Fission onto the stock market by having a private company acquire an existing publicly listed entity. In that deal, Deep Fission raised $30 million in a concurrent private placement at $3 a share.

But the earlier listing, as it turns out, was public in name only. The reverse merger was completed, making Deep Fission a reporting company with SEC obligations—yet the stock never actually traded.

Deep Fission had said it intended to list on the OTCQB. a marketplace for developing companies that don’t meet major exchange requirements like those of the NYSE or Nasdaq. Yet searches for Deep Fission on OTCQB don’t return any results. In its S-1, the company also denied that its stock had ever been publicly traded.

When asked about the discrepancy, Deep Fission declined to comment, citing the quiet period before its IPO.

Now, the company is trying again through a more traditional IPO route. The new offering on Nasdaq is structured in a way that values the company at up to $1.66 billion—an enormous figure for a company that, one year ago, was struggling to raise a $15 million funding round.

The new filing adds another layer of unease. Deep Fission’s timeline for turning on its first reactor has slipped. Back in December. it had hoped to reach criticality—the point at which a nuclear chain reaction becomes self-sustaining—by July 2026. In the latest S-1 filed on May 20. the company won’t provide an estimate for when it might reach that milestone.

Deep Fission points to drilling as evidence of progress. It says it is drilling a test well. But it has also lost a lot of money, and it’s telling investors to watch the clock.

The “going concern” warning in the new S-1 matches the one present in the December filing: if Deep Fission doesn’t complete the IPO, it could run out of money in the next 12 months.

Its financial footing has worsened. As of March, the company’s deficit grew to $88.1 million from $56.2 million. Over the last month and a half, Deep Fission’s cash and cash equivalents declined by $6.4 million—about 7%.

On the technical front, Deep Fission says it is prioritizing drilling. It says it started drilling the first of three test wells in March. The well is intended to collect data “up to 6. 000 feet deep.” Its borehole is planned to be eight inches in diameter. smaller than what will be needed at commercial scale.

The company says that moving from a test well to commercial scale will require boreholes 30 to 50 inches in diameter and a mile deep. though Deep Fission hasn’t settled on a specific dimension yet. Until the company knows how large a hole it can drill, it will be difficult to finalize its reactor design.

So what changed since December that would justify a bigger offering and a nine-figure valuation?. Deep Fission did receive an $80 million equity investment, including $20 million from data center developer Blue Owl. Blue Owl also signed a non-binding MOU for future power plants. Still, that wasn’t enough to stave off the going concern warning.

There’s a possibility the new S-1 leaves out positive information that could help explain why investors are being asked to price in such a large valuation. But given what’s at stake—cash runway tied directly to whether the IPO closes—that explanation would be surprising.

More likely, Deep Fission is betting on investor appetite for fission power itself. Nuclear enthusiasm has been quick to outrun the hard parts of building systems that must work safely for years.

Just last month, nuclear fission startup X-energy went public in an upsized IPO. But X-energy is generating revenue and is significantly farther along in the Nuclear Regulatory Commission’s licensing process. That contrast is a reminder, plain and difficult, that in this sector valuation and progress can diverge fast.

Deep Fission isn’t saying it’s running toward the IPO because the technical work is suddenly accelerating. And the record it’s offering—cash shrinking, losses expanding, reactor timelines slipping—doesn’t make that claim.

It leaves one uneasy thread hanging: a company that says it is drilling and building. seeking major market backing again. after a “going public” moment that never actually resulted in a trading stock. Now the Nasdaq IPO is the test. If it fails, the warning already in its filings is blunt—Deep Fission says it may not have time.

Deep Fission nuclear startup subterranean reactors AI data centers Nasdaq IPO reverse merger Surfside Acquisition SEC reporting company OTCQB going concern Blue Owl test wells fission power