Deep Isolation Nuclear, Inc.
DBHL- Exchange
- OTC
- Industry
- Refuse Systems
- SEC CIK
- 0001918080
No open-market purchases or sales by Deep Isolation Nuclear, Inc. insiders were filed in the last 90 days; no institution reported holding it in 13F filings for Q2 2026; no superinvestor holds it.
Holders of 5% or more of DBHL
Holders whose latest Schedule 13D or 13G filing reports 5% or more of Deep Isolation Nuclear, Inc., largest stake first. The change is against the holder's previous filing.
| Holder | Latest form | Stake | Change | First filed | Latest filing | Filing |
|---|---|---|---|---|---|---|
| Muller Elizabeth | 13D | 22.10%12.7M shares | New | Aug 18, 20251 filing | Aug 18, 2025 | SEC |
| Spieker Warren Edward JR | 13G | 10.30%5.90M shares | New | Aug 14, 20251 filing | Aug 14, 2025 | SEC |
| Mercer Robert L. | 13G | 6.50%3.75M shares | New | Aug 14, 20251 filing | Aug 14, 2025 | SEC |
| Muller Richard | 13G | 5.80%3.34M shares | New | Aug 18, 20251 filing | Aug 18, 2025 | SEC |
| Tompkins Mark N. | 13G/A | 5.50%3.15M shares | +1.54 ppfrom 3.96% | Feb 10, 20233 filings | May 15, 2026 | SEC |
Stakes are as of each holder's latest filing. Holders whose last filing was in the old format (before December 18, 2024) have no stake on record and are not listed, and after an acquisition or delisting holders usually stop filing.
13D and 13G filings
8 Schedule 13D and 13G filings on Deep Isolation Nuclear, Inc., newest first, including old-format filings without a stake.
| Filed (ET) | Filer | Form | Stake | Change | Event date | Filing |
|---|---|---|---|---|---|---|
| May 15, 20265:15 PM ET | Tompkins Mark N. | 13G/A | 5.50%3.15M shares | +1.54 ppfrom 3.96% | Mar 31, 2026 | SEC |
| Nov 14, 20253:36 PM ET | Tompkins Mark N. | 13G/A | 3.96%2.27M shares | –Below 5% | Sep 30, 2025 | SEC |
| Aug 18, 20258:13 PM ET | Muller Richard | 13G | 5.80%3.34M shares | New | Jul 23, 2025 | SEC |
| Aug 18, 20258:12 PM ET | Muller Elizabeth | 13D | 22.10%12.7M shares | New | Jul 23, 2025 | SEC |
| Aug 14, 20258:28 PM ET | Spieker Warren Edward JR | 13G | 10.30%5.90M shares | New | Jul 23, 2025 | SEC |
| Aug 14, 20255:00 PM ET | Mercer Robert L. | 13G | 6.50%3.75M shares | New | Jul 23, 2025 | SEC |
| Feb 13, 2023 | Jacobs Ian Seth | 13GOld format | – | New | – | SEC |
| Feb 10, 2023 | Tompkins Mark N. | 13GOld format | – | New | – | SEC |
Form 144: proposed insider sales
Notices from officers, directors and other affiliates planning to sell Deep Isolation Nuclear, Inc. shares.
No Form 144 notices for Deep Isolation Nuclear, Inc. are on file.