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 Funding Rounds and IPO Valuation

Date Funding Round Funding Raised Price per Share IPO Valuation
5/24/2022 Series E and E-1 $858.55MM $XXX.XX $XXX.XX
5/4/2021 Series D $440.31MM $XXX.XX $XXX.XX
1/24/2018 Series C $245.46MM $XXX.XX $XXX.XX
8/29/2017 Series B $110.16MM $XXX.XX $XXX.XX
7/1/2011 Series A and A-1 $25.97MM $XXX.XX $XXX.XX
Based on primary financings
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What is Mainspring funding to date?

Mainspring has raised $392.55MM with the following series:
$25.97MM for Series A and A-1, $110.16MM for Series B, $245.46MM for Series C, $440.31MM for Series D, $858.55MM for Series E and E-1, $25.97MM for Series A and A-1, $110.16MM for Series B, $245.46MM for Series C, $440.31MM for Series D, $858.55MM for Series E and E-1.
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When was Mainspring founded?

Mainspring was founded in 2010.