Mainspring Stock

mainspringenergy.comEnergy / Clean EnergyFounded: 2010Funding to Date: $746.62MM

Mainspring is developing a new approach to generating clean, resilient, affordable electricity. Their research into high-efficiency methods of converting fuel to electricity led to the development and prototype of their first linear generator. This company was founded by John Connolly and Marshall Micheals in 1996 and is headquartered in Cambridge, MA.

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Mainspring Stock Price

Forge Price 1
Price not yet available
Last Closed Trade 2
Close Date
xx/xx/xx
Last Closed Trade Price
$xx.xx
Last Funding Round (LFR)
Date
xx/xx/xx
Price per Share
$xx.xx

Mainspring Funding Rounds and Valuation

Funding History Chart
Funding Round Details
Funding Date Share Class Amount Raised Price per Share Post-Money Valuation Key Investors
11/26/2024 Series F-1 $41.14MM $xx.xx $1.51B Undisclosed Investors
Price per Share
$xx.xx
Shares Outstanding
13,821,080
Liquidation Pref Order
1
Liquidation Pref As Multiplier
1.0x
Conversion Ratio
1.0x
Dividend Rate
8.0%
Cumulative
Non-cumulative
Participating
Non-participating
Participation Cap
--
Key Investors
Undisclosed Investors
11/26/2024 Series F $159.55MM $xx.xx $1.51B Undisclosed Investors
Price per Share
$xx.xx
Shares Outstanding
42,882,709
Liquidation Pref Order
1
Liquidation Pref As Multiplier
1.0x
Conversion Ratio
1.0x
Dividend Rate
8.0%
Cumulative
Non-cumulative
Participating
Non-participating
Participation Cap
--
Key Investors
Undisclosed Investors
09/21/2022 Series E-1 $18.91MM $xx.xx $1.04B Bill Gates, Cpp Investments, Fidelity, Fine Structure Ventures, Hanwha Power Systems, Khosla Ventures, Lightrock, Lineage Ventures, Princeville Capital, Shell Ventures
Price per Share
$xx.xx
Shares Outstanding
2,467,100
Liquidation Pref Order
2
Liquidation Pref As Multiplier
1.0x
Conversion Ratio
1.0x
Dividend Rate
8.0%
Cumulative
Non-cumulative
Participating
Non-participating
Participation Cap
--
Key Investors
Bill Gates, Cpp Investments, Fidelity, Fine Structure Ventures, Hanwha Power Systems, Khosla Ventures, Lightrock, Lineage Ventures, Princeville Capital, Shell Ventures
09/21/2022 Series E $284.47MM $xx.xx $1.04B Bill Gates, Cpp Investments, Fidelity, Fine Structure Ventures, Hanwha Power Systems, Khosla Ventures, Lightrock, Lineage Ventures, Princeville Capital, Shell Ventures
Price per Share
$xx.xx
Shares Outstanding
35,251,855
Liquidation Pref Order
2
Liquidation Pref As Multiplier
1.0x
Conversion Ratio
1.0x
Dividend Rate
8.0%
Cumulative
Non-cumulative
Participating
Non-participating
Participation Cap
--
Key Investors
Bill Gates, Cpp Investments, Fidelity, Fine Structure Ventures, Hanwha Power Systems, Khosla Ventures, Lightrock, Lineage Ventures, Princeville Capital, Shell Ventures
05/04/2021 Series D $108.35MM $xx.xx $440.31MM 40 North Ventures, Aep, Bill Gates, Chevron Technology Ventures, Clearsky, Devonshire Investors, Equinor, Kck, Khosla Ventures, Princeville Capital
Price per Share
$xx.xx
Shares Outstanding
20,055,578
Liquidation Pref Order
3
Liquidation Pref As Multiplier
1.0x
Conversion Ratio
1.0x
Dividend Rate
8.0%
Cumulative
Non-cumulative
Participating
Non-participating
Participation Cap
--
Key Investors
40 North Ventures, Aep, Bill Gates, Chevron Technology Ventures, Clearsky, Devonshire Investors, Equinor, Kck, Khosla Ventures, Princeville Capital
01/24/2018 Series C $84.3MM $xx.xx $245.46MM American Electric Power, Bill Gates, Centrica Innovations, Kck Group, Khosla Ventures, Louis M. Bacon, Statoil Energy Ventures
Price per Share
$xx.xx
Shares Outstanding
19,546,914
Liquidation Pref Order
4
Liquidation Pref As Multiplier
1.0x
Conversion Ratio
1.0x
Dividend Rate
8.0%
Cumulative
Non-cumulative
Participating
Non-participating
Participation Cap
--
Key Investors
American Electric Power, Bill Gates, Centrica Innovations, Kck Group, Khosla Ventures, Louis M. Bacon, Statoil Energy Ventures
08/29/2017 Series B $40.04MM $xx.xx $110.16MM Undisclosed Investors
Price per Share
$xx.xx
Shares Outstanding
10,569,940
Liquidation Pref Order
5
Liquidation Pref As Multiplier
1.0x
Conversion Ratio
1.0x
Dividend Rate
8.0%
Cumulative
Non-cumulative
Participating
Non-participating
Participation Cap
--
Key Investors
Undisclosed Investors
07/01/2011 Series A $2.86MM $xx.xx $25.97MM Undisclosed Investors
Price per Share
$xx.xx
Shares Outstanding
3,169,952
Liquidation Pref Order
5
Liquidation Pref As Multiplier
1.0x
Conversion Ratio
1.0x
Dividend Rate
8.0%
Cumulative
Non-cumulative
Participating
Non-participating
Participation Cap
--
Key Investors
Undisclosed Investors
07/01/2011 Series A-1 $7MM $xx.xx $25.97MM Undisclosed Investors
Price per Share
$xx.xx
Shares Outstanding
3,708,413
Liquidation Pref Order
5
Liquidation Pref As Multiplier
1.0x
Conversion Ratio
1.0x
Dividend Rate
8.0%
Cumulative
Non-cumulative
Participating
Non-participating
Participation Cap
--
Key Investors
Undisclosed Investors

Mainspring Investors Also Invested in These Private Companies

Louis M. Bacon
Lineage Ventures
Centrica Innovations
Hanwha Power Systems
American Electric Power
40 North Ventures
Statoil Energy Ventures
Fine Structure Ventures

Leadership & Board

Leadership

Shannon Miller
Chief Executive Officer and Founder
Matt Svrcek
Chief Technology Officer and Founder
Adam Simpson
Chief Product Officer and Founder
David DeGraaff
Chief Operating Officer
Jim Dawe
Chief Commercial Officer
Gary Larsen
Chief Financial Officer
Maria Amundson
Chief Communications Officer
Ryan Fletcher
Vice President of Finance
Kirk Gerber
Vice President of Global Supply Chain and Operations
Haben Goitom
Vice Presdient and Commercial Counsel
Bobby Hollis
Vice President of Market and Development
John Igo
Vice President of Business Development
Greg Pal
Vice President of Product
Yannick Roux
Vice President of Product Introduction

Mainspring stock FAQs

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Can you buy Mainspring stock?

As Mainspring is not publicly traded, purchasing its stock is not available to everyone. To buy the stock of a private companies like Mainspring, you must be an accredited investor. If you meet the accreditation criteria, you can register for Forge’s Secondary Marketplace to buy private market stock. If you are not accredited, find out how to begin the process and qualify for new investment opportunities.
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How to buy Mainspring stock?

To invest in a private company like Mainspring through Forge, you must first qualify as an accredited investor. (Learn more about the accreditation process.)

  1. Create a free account to access Forge’s marketplace.
  2. Express your interest in specific investments. Within Forge Markets, you will find detailed pricing and financing information for thousands of private companies.
  3. Throughout this process, a dedicated Forge Private Market Specialist will be available to address any questions you may have and to guide you seamlessly through each step of the transaction.
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Can you sell Mainspring stock?

Yes, you may sell the Mainspring stock you currently own. Forge can help you facilitate the sale of your stock in a manner that aligns with your needs and the company’s interests. If you are looking for liquidity, register with us today to begin the process. A dedicated Forge Private Market Specialist will be available to address any questions you may have along the way.
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How to sell Mainspring stock?

If you hold private company shares of Mainspring – whether as an employee or an early investor – Forge can help you sell them.

  1. Create a free Forge account, this will give you access to Forge’s marketplace and to one of our experienced Private Market Specialist to answer any questions you might have.
  2. Indicate your interest to sell your Mainspring on our platform.
  3. Work with your dedicated Private Market Specialist who’ll help guide you through every step of the transaction.
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Is Mainspring a public company?

No, Mainspring is a privately held company and is currently not publicly traded on any stock markets including NYSE or NASDAQ.
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What is Mainspring’s stock price?

Mainspring is a privately held company and therefore does not have a public stock price. However, you may access Mainspring private market stock price with Forge Data.
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What is Mainspring’s stock ticker symbol?

Mainspring does not have an official ticker symbol because this company is not currently publicly traded.
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Can institutional investors buy and sell private market stocks?

Yes. As one of the largest trading platform for the private market, Forge helps institutional investors seek liquidity as they buy and sell private stock for their portfolios or their clients. Our private market specialists have decades of experience working with institutional firms. Learn more or register today to get started.

Mainspring News and Media Highlights

Mainspring Closes Series E at $290 Million

On May 24th this year, simultaneously with announcing a major commercial sales deal, Mainspring disclosed it had completed its first close of the Series E at $150 million. The company has since expanded the raise by an additional $140 million, to reach the $290 million Series E final close.
Browse Insights
Updated on: Dec 23, 2024

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