Deep Fission FISN Insider Ownership

NASDAQ FISN
$7.11 +0.13 (+1.86%)
At close: Sep 9, 2026 · 4:00 PM EDT

Insider Holdings by Owner

18.27Mn Shares

Insider Ownership Statistics

as of 30 Sep, 2026
Insider Ownership
share count not reported for this filer set
Shares Held by Insiders
18.27Mn
filed for Sep 2026
0.00% QoQ
Shares Outstanding
not reported
Direct Holdings
13.21Mn
Indirect: 5.06Mn
Net Shares Traded (QoQ)
0
no net change in Sep 2026
Insiders Holding Shares
5
with Form 4 holdings on file

Shares Owned by Insiders

Shares held % of outstanding
Latest
Average ownership
Peak ownership

Shares Purchased/Sold by Insiders

Bought Sold
Latest quarter
Net over range
Buying quarters
Form 4 Holdings

Insiders Holding FISN

Insiders 5
Shares held 18.27Mn
Of outstanding
# Insider Position Direct Indirect Total Share of Insiders Last Filed
1 Elizabeth Muller Chief Executive Officer 5,745,877 5,057,855 10,803,732 59.1% 12 Dec, 2025
2 Richard Muller Chief Technology Officer 5,196,426 0 5,196,426 28.4% 09 Sep, 2025
3 Mark N. Tompkins Other 1,891,667 0 1,891,667 10.4% 08 Sep, 2025
4 Ian Seth Jacobs President, Ceo, Cfo, Secretary 275,000 0 275,000 1.5% 28 Aug, 2025
5 William Mark Schmitz Chief Financial Officer 103,928 0 103,928 0.6% 09 Sep, 2025

Each row is that insider’s most recently reported position, from Form 4 filings over the last 60 months — which is why this total does not tie to the quarterly series above, where a quarter counts only the insiders who filed in it. Shares held through a fund or institutional portfolio are counted on the institutional ownership page instead.

Form 4 Filings

77 Insider Transactions

Source SEC Form 4
Latest quarter Sep 2026
Download Data
Date Insider Position Transaction Shares Price Value Shares Held After Ownership
23 Jul, 2026 Jonathon Angell Director Acquired A 16,973 $0.00 $0 16,973 Direct
23 Jul, 2026 Tepper Leslie Goldman Director Acquired A 19,204 $0.00 $0 19,204 Direct
23 Jul, 2026 Thomas S Glanville Director Acquired A 19,156 $0.00 $0 19,156 Direct
09 Mar, 2026 Elizabeth Muller Chief Executive Officer Acquired A 2,600,000 $0.00 $0 4,150,300 Direct
09 Mar, 2026 William Mark Schmitz Chief Financial Officer Acquired A 223,000 $0.00 $0 223,980 Direct
09 Mar, 2026 Richard Muller Chief Technology Officer Acquired A 223,000 $0.00 $0 872,363 Direct
09 Mar, 2026 William Mark Schmitz Chief Financial Officer Acquired A 223,000 $0.00 $0 223,980 Direct
09 Mar, 2026 Richard Muller Chief Technology Officer Acquired A 223,000 $0.00 $0 872,363 Direct
09 Mar, 2026 Jonathan H Gordon General Counsel Acquired A 223,000 $0.00 $0 328,000 Direct
09 Mar, 2026 Mark Wayne Peres Chief Nuclear Officer Acquired A 223,000 $0.00 $0 263,000 Direct
09 Mar, 2026 Jonathan H Gordon General Counsel Acquired A 223,000 $0.00 $0 328,000 Direct
09 Mar, 2026 Elizabeth Muller Chief Executive Officer Acquired A 2,600,000 $0.00 $0 4,150,300 Direct
09 Mar, 2026 Mark Wayne Peres Chief Nuclear Officer Acquired A 223,000 $0.00 $0 263,000 Direct
09 Mar, 2026 William Mark Schmitz Chief Financial Officer Acquired A 223,000 $0.00 $0 223,980 Direct
09 Mar, 2026 Elizabeth Muller Chief Executive Officer Acquired A 2,600,000 $0.00 $0 4,150,300 Direct
09 Mar, 2026 Mark Wayne Peres Chief Nuclear Officer Acquired A 223,000 $0.00 $0 263,000 Direct
09 Mar, 2026 Richard Muller Chief Technology Officer Acquired A 223,000 $0.00 $0 872,363 Direct
09 Mar, 2026 William Mark Schmitz Chief Financial Officer Acquired A 223,000 $0.00 $0 223,980 Direct
09 Mar, 2026 Elizabeth Muller Chief Executive Officer Acquired A 2,600,000 $0.00 $0 4,150,300 Direct
09 Mar, 2026 Jonathan H Gordon General Counsel Acquired A 223,000 $0.00 $0 328,000 Direct