Zephyr Fusion
PrivateLast Round
Seed
Dec 8, 2025
Est. Valuation
$1.79M
Total Funding Raised
$500,000
Momentum
Top 5%
of companies Caplight tracks
Company Overview
Zephyr Fusion is an aerospace and energy company developing a compact, megawatt-class fusion reactor designed for in-orbit power generation to support large-scale space industrialization.
Sector
Frontier & Industrial Tech
Verticals
Space Technology, Energy Storage
Business Model
B2B
Customer Profile
Hardware Sales, Government Contracts, Hardware + Subscription
AI Layer
Non-AI
Keywords
Historical Pricing
Historical view of private secondary pricing and transaction trends.
Zephyr Fusion Comparables
Compare Zephyr Fusion with similar companies based on industry and business-model similarity.
| Company | Similarity | Market Cap |
|---|---|---|
| Princeton Satellite Systems | 72% | |
| NANO Nuclear Energy | 71% | |
| Pulsar Fusion | 69% |
Zephyr Fusion Funding Rounds
Historical fundraising activity
| Round | Date | Amount Raised | Valuation | Investors | Sources |
|---|---|---|---|---|---|
| Seed | Dec 8, 2025 |
Zephyr Fusion Investors
Notable investors and investment history
| Investor | Rounds |
|---|---|
| Pioneer Fund | Seed |
| Brimstone Hill Capital | Seed |
| Y Combinator | Seed |
| Syntax Ventures | Seed |
| Nova Threshold | Seed |
| Alumni Ventures | Seed |
| Spot VC | Seed |
Market signals
Structured signals derived from secondary market and firmographic data.
- Sep 17, 2026
Grew 43% QoQ from 7 to 10 employees.
- Sep 13, 2026
Monthly visitors increased 69% MoM.
Zephyr Fusion Filings
Explore SEC and related filing metadata, where available.
| Type | Date | Amount Offered | Amount Sold | Filing | Pages | Download |
|---|
Filing documents are not displayed on this public page. Request access to learn about available coverage.
Request accessFrequently Asked Questions
Common questions about Zephyr Fusion's valuation, stock price, and market status.
Is Zephyr Fusion a public or private company?
Zephyr Fusion is a private company.
What is the current stock price of Zephyr Fusion?
Zephyr Fusion is a private company, so its shares have no public market price. Caplight tracks Zephyr Fusion's secondary market activity and provides MarketPrice™ estimates of its share price to Caplight users.
How much is Zephyr Fusion worth (valuation)?
Zephyr Fusion's valuation is estimated at $1.8M based on funding round data.
Can I buy Zephyr Fusion stock?
Zephyr Fusion shares may be available on secondary markets subject to transfer restrictions. Caplight facilitates secondary market transactions for accredited investors.
When was Zephyr Fusion's last funding round?
Zephyr Fusion's most recent funding round was Seed on December 8, 2025.
Who are the main investors in Zephyr Fusion?
Key investors in Zephyr Fusion include Y Combinator.
Will Zephyr Fusion IPO soon?
No public IPO plans have been announced for Zephyr Fusion.
How can I track Zephyr Fusion secondary market activity?
Caplight tracks bids, offers, and trades in Zephyr Fusion's shares on secondary markets.