Funding round
Radiant Nuclear Series D
Radiant Nuclear, which works in nuclear microreactor development and manufacturing in El Segundo, raised $300M in a Series D round announced on 17 Dec 2025, led by Draper Associates and Boost VC, at a $1.80B post-money valuation. 10 firms took part, 10 of them already investors. It is Radiant Nuclear's fourth venture round on record; the one before was a Series C in May 2025.
$300M
Amount raised
$1.80B
Post-money valuation
$1.50B pre-money
10
Investors
2 leads
17%
Stake sold
new money over the post-money
Valuation
What this round says about the price
This round priced Radiant Nuclear at $1.80B after the new money. The $300M bought investors about 17% of the company. It came 7 months after Radiant Nuclear's Series C. It is 58% of the $518M Radiant Nuclear has raised in the venture rounds on record. No later venture round is on record for Radiant Nuclear.
Radiant Nuclear's funding rounds
Radiant Nuclear has 4 venture rounds on record. This one is highlighted.
Investors
Who put money in
Draper Associates and Boost VC led the round with 8 other firms. Draper Associates, Boost VC, Ark Venture Fund and Chevron Technology Ventures and 6 more had backed Radiant Nuclear before.
Lead investors
- backs 105 venture-backed companies existing investor
- backs 77 venture-backed companies existing investor
Also in the round
- Ark Venture Fund existing investor
- Chevron Technology Ventures existing investor
- backs 28 venture-backed companies existing investor
- Founders Fund backs 368 venture-backed companies existing investor
- backs 30 venture-backed companies existing investor
- Andreessen Horowitz backs 722 venture-backed companies existing investor
- Align Ventures existing investor
- DCVC backs 171 venture-backed companies existing investor
Use of proceeds
What the money is for
According to the announcement, the money goes to product development, scaling operations and working capital.
- Product development
- Scaling operations
- Working capital
Comparable rounds
How it compares
The closest in time: 1 in Electric Supplies & Power Generation, then Series D rounds in any sector within 6 months:
| Company | Announced | Amount | Post-money | Led by |
|---|---|---|---|---|
| Electric Supplies & Power Generation | 4 Dec 2024 | $67M | not disclosed | not named |
| Eon Tech Companies | 2 Dec 2025 | $300M | $4.00B | Gil Capital |
| Tech Companies | 2 Dec 2025 | $233M | not disclosed | NTT Group and Qatar Investment Authority |
| Imprint Financial Services | 18 Dec 2025 | $150M | $1.20B | Khosla Ventures |
| Tech Companies | 9 Dec 2025 | $140M | $4.50B | Sequoia Capital |
| Insurance - Agents, Carriers & Brokers | 18 Dec 2025 | $100M | $1.50B | Valor |
| Software Development Services | 15 Dec 2025 | $86M | $750M | Georgian and Hedosophia |
| Batteries | 8 Dec 2025 | $81M | not disclosed | Amazon.com, Inc. |
Sources
Where this comes from
Reported by 2 sources.
Questions
Frequently asked
How much did Radiant Nuclear raise in its Series D round?
Radiant Nuclear raised $300M in its Series D round, announced in Dec 2025.
Who led Radiant Nuclear's Series D round?
Draper Associates and Boost VC led it, with Ark Venture Fund, Chevron Technology Ventures, Friends & Family Capital, Founders Fund and Washington Harbour and 3 more.
What was Radiant Nuclear's valuation at the Series D round?
$1.80B post-money ($1.50B pre-money).