Invest and Sell Mainspring Stock

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

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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
	04/14/2025	Series F	$229.38MM	$xx.xx	$973.71MM	Amazon, Dcvc, Gates Frontier, General Catalyst, Khosla Ventures, Lgt Group, Lightrock, Marunouchi Innovation Partners, M&G Investments, Pictet, Temasek
Price per Share $xx.xx Shares Outstanding 61,651,237 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 Amazon, Dcvc, Gates Frontier, General Catalyst, Khosla Ventures, Lgt Group, Lightrock, Marunouchi Innovation Partners, M&G Investments, Pictet, Temasek
	04/14/2025	Series F-1	$28.62MM	$xx.xx	$973.71MM	Amazon, Dcvc, Gates Frontier, General Catalyst, Khosla Ventures, Lgt Group, Lightrock, Marunouchi Innovation Partners, M&G Investments, Pictet, Temasek
Price per Share $xx.xx Shares Outstanding 9,615,458 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 Amazon, Dcvc, Gates Frontier, General Catalyst, Khosla Ventures, Lgt Group, Lightrock, Marunouchi Innovation Partners, M&G Investments, Pictet, Temasek
	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 1.2x 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-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 1.2x 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 1.1x 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, 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 1.1x Dividend Rate 8.0% Cumulative Non-cumulative Participating Non-participating Participation Cap -- Key Investors American Electric Power, Bill Gates, Centrica Innovations, Kck, 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-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
	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

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Mainspring stock FAQs

To buy and sell Mainspring stock

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.

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.)

Create a free account to access Forge’s marketplace.
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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.

How to sell Mainspring stock?

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To learn more about Mainspring stock

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.

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.

What is Mainspring’s stock ticker symbol?

Mainspring does not have an official ticker symbol because this company is not currently publicly traded.

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.

Leadership and 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 news and media highlights

FinSMEs 04/15/2025

Mainspring Raises $258M in Financing

Mainspring, a Menlo Park, CA-based linear generator products company, raised $258M in Series F funding.

PR Newswire 10/03/2022

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.

Other companies like Mainspring in the Clean Energy sector

Sector: Energy

Subsector: Clean Energy

					Last Funding Round
Company		Forge Price	Forge Price Change ⁵	Last Closed Trade	Share Class	Post-Money Valuation	Price per Share	Amount Raised
	Commonwealth Fusion	--	--	$xx.xx	--	--	--	--
	Electric Hydrogen	--	--	$xx.xx	Series C-1	$1.39B	$xx.xx	$979,980.31
	Fervo Energy	--	--	$xx.xx	Series D-3	$1.45B	$xx.xx	$134.5MM
	Helion Energy	--	--	$xx.xx	Series F	$5.43B	$xx.xx	$346.4MM
	Ovo Energy	--	--	$xx.xx	--	--	--	--
	Persefoni	$8.69	-13.10%	$xx.xx	Series C-2-X	$514.31MM	$xx.xx	$16.58MM
	TAE Technologies	$18.93	-81.07%	$xx.xx	Series 11	$5.16B	$xx.xx	$148.26MM
	Twelve	$4.02	+56.42%	$xx.xx	Series C-4	$1.32B	$xx.xx	$5MM
	X-energy	--	--	$xx.xx	--	--	--	--
	Zap Energy	--	--	$xx.xx	Series C	$674.07MM	$xx.xx	$160.61MM

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Updated on: Apr 17, 2025

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Mainspring stock