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Company records / deepfission.com

Deep Fission

Deep Fission (deepfission.com): 3 changes recorded in its website history since July 2023. Homepage last checked 5 November 2026.

Recorded changes

Newest observations first. Each interval bounds when the website changed; it is not an exact event date.

  1. HiringBetween and

    Added a careers page.

    Observed on the company’s website; business claims are not independently verified.

    earlier archived pagelater archived pageLink to observation
  2. HeadlineBetween and
    BeforePowering Humanity from a Mile Underground
    AfterDeep Fission, Inc.

    Observed on the company’s website; business claims are not independently verified.

    earlier archived pagelater archived pageLink to observation
  3. HeadlineBetween and
    BeforeThe future of nuclear will be boring
    AfterPowering Humanity from a Mile Underground

    Observed on the company’s website; business claims are not independently verified.

    earlier archived pagelater archived pageLink to observation

First recorded website

Observed 22 July 2023

Our earliest capture with readable facts. This is our first observation, not when the company introduced these things. These website claims are not independently verified.

How it described itself

Deep Fission – A Nuclear Reactor Under 10 Billion Tons of Rock

A Nuclear Reactor Under 10 Billion Tons of Rock

archived pageLink to first observation

All facts above belong to this capture. Unlisted fields mean we have no readable observation, not that they were absent.

How it describes itself

Similar headlines are grouped together. The quote shown is from the last capture in each group, not necessarily the exact wording throughout that period.

  1. July 2026 – November 2026 · 3 captures · latest observed messagingDeep Fission, Inc.

    Deep Fission is an advanced nuclear energy deployment company developing small modular pressurized water reactors designed to operate one mile underground. Advanced nuclear for the AI era.

    This wording observed 5 November 2026.

    current websiteHistorical capture not publicly available
    Inspect 3 captures in this group
  2. July 2025 – January 2026 · 2 capturesPowering Humanity from a Mile Underground

    A pioneering advanced nuclear energy company placing small modular pressurized water reactors in boreholes one mile underground.

    This wording observed 6 January 2026.

    archived page
    Inspect 2 captures in this group
    • 15 July 2025 · Powering Humanity from a Mile Underground archived page
    • 6 January 2026 · Powering Humanity from a Mile Underground archived page
  3. July 2024 – January 2025 · 2 capturesThe future of nuclear will be boring

    Innovative US nuclear energy company Deep Fission launches underground scalable 15MW, affordable, small modular reactors.

    This wording observed 7 January 2025.

    archived page
    Inspect 2 captures in this group
  4. July 2023 – June 2024 · 2 capturesDeep Fission – A Nuclear Reactor Under 10 Billion Tons of Rock

    A Nuclear Reactor Under 10 Billion Tons of Rock

    This wording observed 4 June 2024.

    archived page
    Inspect 2 captures in this group
    • 22 July 2023 · Deep Fission – A Nuclear Reactor Under 10 Billion Tons of Rock archived page
    • 4 June 2024 · Deep Fission – A Nuclear Reactor Under 10 Billion Tons of Rock archived page

Cite this record

StartupHistory, “Deep Fission” company record, https://startuphistory.org/c/deepfission.com

Machine-readable: /c/deepfission.com.json. How changes are found: method.