Recent 8-K filings for FISN

• June 22, 2026, 4:20 PM ET other material materiality 0.75 positive item 8.01

  Deep Fission completes IPO, raises $40M at $16.00 per share; stock begins trading on Nasdaq

  Offered 2.5M shares at $16.00/share; gross proceeds of $40M.

• April 22, 2026, 7:59 PM ET other material materiality 0.70 neutral item 7.01item 9.01

  Deep Fission confidentially submits draft S-1 for proposed IPO of common stock

  Confidential submission of Form S-1 to SEC for a proposed public offering of common stock.

• April 9, 2026, 7:59 PM ET regulatory materiality 0.85 negative item 4.02 ◈ Auditor Changes

  Deep Fission restates financials due to SAFE and stock-comp valuation errors

  Board determined Q2/Q3 2025 interim and FY 2024 audited statements are unreliable due to valuation model input errors for SAFEs and stock-based compensation.

• March 5, 2026, 6:59 PM ET regulatory materiality 0.50 neutral item 4.01item 9.01 ◈ Auditor Changes ×2

  Deep Fission replaces auditor dbbmckennon with Grant Thornton; material weakness in internal controls disclosed

  Audit committee approved Grant Thornton as new independent auditor; dbbmckennon dismissed effective Feb 27, 2026.

• February 25, 2026, 6:59 PM ET leadership materiality 0.50 neutral item 5.02

  Deep Fission appoints Chief Nuclear Officer; CEO receives $380K bonus

  Mark Pérès appointed Chief Nuclear Officer effective Feb 19, 2026; base salary $300,000, target bonus 30%, 25,000 RSUs with service- and liquidity-based vesting.

• February 10, 2026, 6:59 PM ET other material materiality 0.75 positive item 1.01item 3.02item 7.01item 8.01item 9.01 ◈ Equity Issuances ×2◈ Material Agreements ×2

  Deep Fission raises $80M in private placement, forms strategic relationship with Blue Owl

  Net proceeds ~$76M from sale of 5,333,333 shares at $15/sh; use for working capital, R&D for first nuclear reactor.

• December 22, 2025, 6:59 PM ET leadership materiality 0.30 neutral item 5.02item 8.01item 9.01

  Deep Fission appoints two independent directors, adopts insider trading policy

  Board expanded to five members; Blake E. Janover (Class I) and Thomas S. Glanville (Class II) appointed effective Dec 19, 2025.

• December 11, 2025, 6:59 PM ET leadership materiality 0.55 neutral item 5.02item 9.01

  Deep Fission CEO Elizabeth Muller receives new compensation package with $475K salary, equity grants

  Annual base salary of $475,000; target performance bonus of 50% of salary.

• December 4, 2025, 6:59 PM ET regulatory materiality 0.70 positive item 7.01item 9.01

  Deep Fission selects Kansas site for DOE advanced reactor pilot; groundbreaking Dec 9

  Pilot site selected at Great Plains Industrial Park in Parsons, Kansas; groundbreaking Dec 9, 2025.

• November 21, 2025, 6:59 PM ET regulatory materiality 0.65 positive item 1.01item 9.01 ◈ Material Agreements

  Deep Fission signs DOE reactor authorization agreement for underground test reactor

  DOE and Deep Fission executed Other Transaction Agreement effective Nov 14, 2025, under EO 14301 pilot program.

• November 12, 2025, 6:59 PM ET leadership materiality 0.60 neutral item 5.02item 9.01

  Deep Fission appoints COO, GC, and two new directors; Muller resigns from board

  Richard A. Muller resigned from board to focus on CTO role; no disagreement with company.

• November 7, 2025, 6:59 PM ET other material materiality 0.80 positive item 7.01item 9.01

  Deep Fission selected for DOE reactor pilot; partnership with Endeavour for 2 GW data center power

  Selected as one of 11 companies for DOE Nuclear Reactor Pilot Program; target criticality by July 4, 2026.

• September 11, 2025, 7:59 PM ET other material materiality 0.85 neutral item 1.01item 2.01item 3.02item 3.03item 4.01item 5.01item 5.02item 5.03item 5.06item 9.01 ◈ Governance Changes ×3

  Deep Fission completes reverse merger with Surfside, raises $30M for nuclear reactors

  Merger closed Sept 5, 2025; Deep Fission becomes public via reverse merger with Surfside Acquisition.

• July 28, 2022, 7:59 PM ET other material materiality 0.30 neutral item 4.01

  Surfside Acquisition appoints Grassi & Co. as new independent auditor for FY2022

  Grassi & Co. appointed as independent registered public accounting firm for fiscal year ending Dec 31, 2022.

• July 19, 2022, 7:59 PM ET other material materiality 0.65 negative item 4.01item 9.01

  Surfside Acquisition's auditor REM resigns; audit report includes going concern paragraph

  Raich Ende Malter & Co. resigned as independent auditor effective July 13, 2022.

Materiality & sentiment trend

Max materiality 0.85 · Median 0.65 · Most common event other_material

5 positive 2 negative 8 neutral

source · FISN on sec.gov