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Mainspring

Mainspring

Private
Menlo Park, CaliforniaEnergy & Sustainabilityhttps://www.mainspringenergy.com/

Last Round

Series F

Apr 14, 2025

Total Funding Raised

$773M

Company Overview

Mainspring Energy is a cleantech company that manufactures and delivers an innovative, fuel-flexible on-site power generator designed to accelerate the transition to a zero-carbon electric grid.

Sector

Energy & Sustainability

Verticals

Smart Grid, Energy Management, Energy Storage, Alternative Fuels

Business Model

B2B

Customer Profile

Hardware Sales, Hardware + Subscription, Government Contracts, Services & Consulting

AI Layer

Application

Keywords

linear generatoron-site power generationfuel-flexible generatorenergy-as-a-serviceEaaSdispatchable powermicrogriddata center powerdistributed energy resourcesDERsbehind-the-meter generationpower purchase agreementPPAhydrogen power generationprime powernon-combustion reactioncommercial and industrial powerammonia power generation

Historical Pricing

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Caplight Momentum Score

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Mainspring Comparables

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Mainspring Funding Rounds

Historical fundraising activity

Data table
RoundDateAmount RaisedValuationInvestorsSources
Series FApr 14, 2025
Series ESep 21, 2022
Series DMay 4, 2021
Series CJan 24, 2018
Series BAug 17, 2012

Mainspring Investors

Notable investors and investment history

Mainspring investors
InvestorRounds
CPP InvestmentsSeries E
Pictet GroupSeries F
40 North VenturesSeries D
Fine Structure VenturesSeries E
TemasekSeries F
Khosla VenturesSeries F, Series C, Series E, Series D, Series A, Series B
Princeville CapitalSeries E, Series D

Market signals

Structured signals derived from secondary market and firmographic data.

  • Apr 14, 2025

    $258M round with Khosla Ventures and LGT Private Banking.

  • Sep 21, 2022

    $290M round led by Lightrock.

Mainspring Filings

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Mainspring filings preview — column headings only; records require access
TypeDateAmount OfferedAmount SoldFilingPagesDownload

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Frequently Asked Questions

Common questions about Mainspring's valuation, stock price, and market status.

Is Mainspring a public or private company?

Mainspring is a private company.

What is the current stock price of Mainspring?

Mainspring is a private company with no public stock price. No recent secondary market data is available.

How much is Mainspring worth (valuation)?

Valuation information for Mainspring is not publicly available.

Can I buy Mainspring stock?

Mainspring shares may be available on secondary markets subject to transfer restrictions. Caplight facilitates secondary market transactions for accredited investors. Visit https://www.caplight.com to learn more.

When was Mainspring's last funding round?

Funding round information for Mainspring is not publicly available.

Who are the main investors in Mainspring?

Investor information for Mainspring is not publicly disclosed.

Will Mainspring IPO soon?

No public IPO plans have been announced for Mainspring.

How can I track Mainspring secondary market activity?

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Firmographic Details

HeadquartersMenlo Park, California
Year Founded2010
Last FundingApr 14, 2025

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