# Complement 1 funding: rounds and investors

> Complement 1 has raised $16M across 1 round since 2025. Investors include Blume Ventures and Owl Ventures. Every round with its source.

Source: https://millionrounds.com/company/complement-1 (Millionrounds; every figure on the page links to its filing or article)

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

# Who invested in *Complement 1*

One round we have observed, with the 2 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.

Healthcare

Funding summary Updated 26 Oct 2026

**$16M** raised across 1 round since 2025, from 1 source

- **Latest round:** Seed, $16M Apr 2025
- **Investors:** 2

See who backed them

## The rounds

- **Apr 2025** Seed **$16M** [Blume Ventures](https://millionrounds.com/fund/blume-ventures) [Owl Ventures](https://millionrounds.com/fund/owl-ventures) Source recorded

## Everyone who backed them

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

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

Missing a round, or an investor who was in one? [Tell us](https://millionrounds.com/corrections?slug=complement-1).

## Also claim to have backed them

This firm lists Complement 1 as a portfolio company on their own website, but no report of a round names it. They are the firms' own claims, kept apart from the rounds above.

[Alphatron Capital](https://millionrounds.com/fund/alphatron-capital) VC firm Per its own site

## Quick answers about Complement 1

### Who invested in Complement 1?

Complement 1's investors include Blume Ventures and Owl Ventures.

### How much has Complement 1 raised?

Complement 1 has raised $16M across 1 round since 2025.

### When did Complement 1 last raise?

Complement 1's most recent round was a Seed of $16M in Apr 2025.

### What was Complement 1's biggest round?

Its most recent round, $16M in Apr 2025, is also its largest on record.

### Who backed Complement 1 first?

Complement 1's first round on record, in Apr 2025, was backed by Blume Ventures and Owl Ventures.

### What stage is Complement 1 at?

Complement 1's latest named round is a Seed, in Apr 2025.

### Where is Complement 1 based?

Complement 1 is based in the United States.

## Companies like Complement 1

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

[**Star Therapeutics** $325M · Oct 2026](https://millionrounds.com/company/star-therapeutics)[**Promaxo** $106M · Oct 2026](https://millionrounds.com/company/promaxo)[**AI** $18M · Oct 2026](https://millionrounds.com/company/ai)[**Baba** $40M · Oct 2026](https://millionrounds.com/company/baba)[**Rejuvenate Bio** $13M · Oct 2026](https://millionrounds.com/company/rejuvenate-bio)[**Clinical Ink** $24M · Oct 2026](https://millionrounds.com/company/clinical-ink)

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