What is Phase Four?
Founded in 2015, Phase Four has established itself as a disruptive force in the electric propulsion (EP) landscape. The company specializes in the development of next-generation thrusters designed to address the specific constraints of small satellite constellations. By prioritizing propellant agnosticism and miniaturized power electronics, Phase Four has successfully moved beyond theoretical design to achieve flight heritage with its Maxwell turn-key propulsion system. This technological milestone has solidified its position as a critical supplier for satellite operators seeking to optimize performance while reducing overall mission costs. The company's architecture is specifically engineered for mass-manufacturability, a key differentiator in an industry historically characterized by bespoke, high-cost hardware solutions.
How much funding has Phase Four raised?
Phase Four has raised a total of $33M across 4 funding rounds:
Debt
$350K
Debt
$359K
Series B
$26M
Other Financing Round
$6.3M
Debt (2020): $350K with participation from PPP
Debt (2021): $359K led by PPP
Series B (2021): $26M supported by New Science Ventures
Other Financing Round (2024): $6.3M featuring Leonid
Key Investors in Phase Four
Leonid Capital Partners
Leonid Capital Partners is a private equity firm focused on middle-market businesses, providing growth capital and strategic financing to drive long-term value creation.
New Science Ventures
New Science Ventures is a venture capital firm that invests in early and late-stage companies utilizing novel scientific approaches in life sciences and information technology.
PPP
Public-Private Partnership
What's next for Phase Four?
Looking ahead, Phase Four is poised to leverage its recent capital infusion to accelerate the deployment of its propulsion solutions across global satellite networks. As the space economy shifts toward high-frequency constellation launches, the company's focus will likely remain on scaling production throughput and refining its RFT architecture to maintain a competitive edge. Strategic priorities include expanding its operational footprint and deepening its integration with major satellite bus manufacturers. By maintaining its trajectory of innovation, Phase Four is well-positioned to capitalize on the long-term growth of the orbital infrastructure market, ensuring that its propulsion systems remain the industry standard for performance and reliability.
See full Phase Four company page
