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PHASE FOUR, INC. competitors & alternatives
The 12 closest competitors and alternatives to PHASE FOUR, INC. among aerospace companies — ranked by similarity to what PHASE FOUR, INC. actually does, not by market-cap band.
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About PHASE FOUR, INC.
Phase Four, Inc. is an aerospace company founded in 2015 that operates in California and develops propulsion technologies.
PHASE FOUR, INC. at a glance
PHASE FOUR, INC. is an aerospace company headquartered in United States. It has raised at least $30.2M across the 5 funding rounds on record, 4 of them with a disclosed amount. Its most recent funding round, Growth, closed in January 2025. Xcout tracks 6 named people at PHASE FOUR, INC., including STEPHEN KISER (Chief Executive Officer).
PHASE FOUR, INC. leadership
- STEPHEN KISERChief Executive Officer
- STEPHEN KISERExecutive Officer
- JAMES BRIDENSTINEDirector
- JAMES J.A. BRIDENSTINEDirector
- Stewart AlsopDirector
- Thomas J.A. LavinDirector
PHASE FOUR, INC. funding rounds
At least $30.2M raised across the 5 rounds on record (4 with a disclosed amount). Every round on record:
| Date | Round | Amount | Investors |
|---|---|---|---|
| Growth | Undisclosed | 1 named | |
| Series B | $20M | 2 named | |
| SEC Form D filing | $5.5M | — | |
| SEC Form D filing | $3.6M | — | |
| SEC Form D filing | $1.1M | — |
Who invested in each round, lead investors, valuations and the co-investor graph — open the full funding history →
Top 12 PHASE FOUR, INC. competitors
Ranked by semantic similarity — how close each company is to PHASE FOUR, INC. by what it does, using Xcout's live company graph. Click any company for its full profile, or its competitor set.
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Radian Aerospace Inc. is an aerospace technology company headquartered in Bellevue, Washington, developing advanced reusable spaceplane technology.
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Bellatrix Aerospace is a private Indian aerospace manufacturer and small satellite company. Headquartered in Bengaluru, Karnataka, the firm develops and manufactures advanced propulsion technologies and in-space mobility solutions.
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Red Canyon Engineering & Software is an aerospace engineering and software-services company supporting spacecraft and space missions. It serves government and commercial aerospace customers, including NASA and defense-related organizations, with systems engineering, flight software, mission operations, and related technical services.
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Sierra Space Corporation is a privately held aerospace and space technologies company headquartered in Louisville, Colorado, with additional facilities in Colorado, Wisconsin, Florida, North Carolina and a testing site at the Marshall Space Flight Center in Alabama. The company makes spaceflight hardware for various applications across the industry.
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