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# Who owns DEEP FISSION, INC. (FISN)? Elite investor 13F holders

1 tracked elite investors reported holding DEEP FISSION, INC as of 2026-09-30, including Renaissance Technologies LLC. Who bought, trimmed or exited each quarter, with links to the original SEC 13F filings.

1 tracked investors currently reported holding · Latest report period: 2026-09-30 · Utilities · Utilities

Deep Fission, Inc. develops and deploys small modular nuclear reactors placed deep underground to generate electricity. The company provides small modular nuclear reactors designed for underground installation at a depth of one mile, offering carbon-free energy and capacity solutions. It delivers scalable reactor configurations for onsite power needs or flexible offtake agreements in wholesale…

## Reported holders and securities, including exits (up to 20)

| Investor | Security | Instrument | Report period | Filed | Value | Quantity | Units | Change | Source |
|  --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| [Renaissance Technologies LLC](https://ownershiptrace.com/13f/investors/63) | DEEP FISSION INC | SHARE | 2026-09-30 | 2026-11-12 00:00:00 | 236421.00 USD | 46086.000000 | Shares | buy | [Original filing](https://www.sec.gov/Archives/edgar/data/1037389/0001037389-26-000062-index.html) |

Public disclosures can be delayed, incomplete, or amended. Report period describes a position date; transaction date describes a reported transaction; filed describes submission. A recent filing or page update does not establish a current holding. A dash means unavailable or not comparable, not zero.

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