# Mainspring Energy funding: rounds and investors

> Mainspring Energy has raised $258M across 1 round since 2025. Investors include General Catalyst, Alumni Ventures and Khosla Ventures.

Source: https://millionrounds.com/company/mainspring-energy (Millionrounds; every figure on the page links to its filing or article)

United States · [Growth startup](https://millionrounds.com/companies)

# Who invested in *Mainspring Energy*

One round we have observed, with the 6 investors named in it. Every figure came from a named source, and where the company reported a raise to the SEC itself, that is shown beside it.

Energy Genomics

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Funding summary Updated 27 Oct 2026

**$258M** raised across 1 round since 2025, from 2 sources

- **Latest round:** Growth, $258M Apr 2025
- **Led by:** General Catalyst
- **Investors:** 6 (1 led)

See who backed them

## The rounds

- **Apr 2025** Growth **$258M** [General Catalyst](https://millionrounds.com/fund/general-catalyst) Lead [Alumni Ventures](https://millionrounds.com/fund/us-strategic-tech-fund-an-alumni-ventures-fund) [Khosla Ventures](https://millionrounds.com/fund/khosla-ventures) [DCVC](https://millionrounds.com/fund/data-collective) [Temasek Holdings](https://millionrounds.com/fund/temasek) [Lightrock](https://millionrounds.com/fund/lightrock) Reported by Crunchbase News and 1 other

## Founders and team

From the SEC filings it signed: 2 on the team.

- **Adam Simpson** Executive Officer, Director i
- **Shannon Miller** Executive Officer, Director i

On the board, as filed i *Alexander Weiss* *Eric Kosmowski* *Jagdeep Singh* *Nael Kassar* *Samir Kaul* *Shyam Kamadolli*

## Everyone who backed them

[General Catalyst](https://millionrounds.com/fund/general-catalyst) VC firm **1** round, led 1

[Alumni Ventures](https://millionrounds.com/fund/us-strategic-tech-fund-an-alumni-ventures-fund) VC firm **1** round

[Khosla Ventures](https://millionrounds.com/fund/khosla-ventures) VC firm **1** round

[DCVC](https://millionrounds.com/fund/data-collective) VC firm **1** round

[Temasek Holdings](https://millionrounds.com/fund/temasek) VC firm **1** round

[Lightrock](https://millionrounds.com/fund/lightrock) VC firm **1** round

Missing a round, or an investor who was in one? [Tell us](https://millionrounds.com/corrections?slug=mainspring-energy).

## Also claim to have backed them

These 3 firms list Mainspring Energy as a portfolio company on their own websites, but no report of a round names them. They are the firms' own claims, kept apart from the rounds above.

[Fine Structure Ventures](https://millionrounds.com/fund/fine-structure-ventures) VC firm Per its own site

[Marunouchi Innovation Partners](https://millionrounds.com/fund/marunouchi-innovation-partners) VC firm Per its own site

[Trog Hawley Capital](https://millionrounds.com/fund/trog-hawley-capital) Family office Per its own site

## Quick answers about Mainspring Energy

### Who invested in Mainspring Energy?

Mainspring Energy's investors include General Catalyst, Alumni Ventures, Khosla Ventures, DCVC and Temasek Holdings, and 1 more on record. General Catalyst led its latest round.

### How much has Mainspring Energy raised?

Mainspring Energy has raised $258M across 1 round since 2025.

### When did Mainspring Energy last raise?

Mainspring Energy's most recent round was a Growth of $258M in Apr 2025, led by General Catalyst.

### What was Mainspring Energy's biggest round?

Its most recent round, $258M in Apr 2025, is also its largest on record.

### Who backed Mainspring Energy first?

Mainspring Energy's first round on record, in Apr 2025, was backed by General Catalyst, Alumni Ventures and Khosla Ventures and 3 others.

### What stage is Mainspring Energy at?

Mainspring Energy's latest named round is a Growth, in Apr 2025.

### Where is Mainspring Energy based?

Mainspring Energy is based in the United States.

### Who led Mainspring Energy's rounds?

General Catalyst led the Growth in 2025.

## Companies like Mainspring Energy

In the same sector, and raised in the last eighteen months.

[**Amogy** $125M · Oct 2026](https://millionrounds.com/company/amogy)[**LanzaJet** $67M · Oct 2026](https://millionrounds.com/company/lanzajet)[**Pivot Energy** $500M · Oct 2026](https://millionrounds.com/company/pivot-energy)[**Pennsylvania American Water** $43M · Oct 2026](https://millionrounds.com/company/pennsylvania-american-water)[**Peak Energy** $163M · Oct 2026](https://millionrounds.com/company/peak-energy)[**Vertical Semiconductor** $84M · Oct 2026](https://millionrounds.com/company/vertical-semiconductor)

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