# Castelion raises $800M Series C led by Andreessen Horowitz

> Castelion, based in United States, has raised $800M in a Series C led by Andreessen Horowitz, JPMorgan Chase's Strategic Investment Group and The Carlyle...

Source: https://millionrounds.com/news/rounds/castelion-series-c-2026-08 (Millionrounds; every figure on the page links to its filing or article)

Raised **$800M** 4 sources reported it

Stage **Series C** 2 earlier rounds on record

Investors **7** 3 named as lead

Where **US** United States

Defence Tech

## How big is it?

Against every equity round we recorded in the twelve months to 21 August 2026. Ranks count companies, so the same raise reported twice is counted once.

**#64** equity round of the last twelve months

**#11** Series C of 194 in that time

**#41** round in United States, of 1,100

This round **$800M**

Median Series C **$100M**

8.0 times the median Series C of the last twelve months.

## Who invested

- [**Andreessen Horowitz** 309 rounds in the last twelve months *Led*](https://millionrounds.com/fund/andreessen-horowitz)
- [**JPMorgan Chase's Strategic Investment Group** 6 rounds in the last twelve months *Led*](https://millionrounds.com/fund/jpmorgan-chase-s-strategic-investment-group)
- [**The Carlyle Group** 2 rounds in the last twelve months *Led*](https://millionrounds.com/fund/the-carlyle-group)

Also in the round

- [General Catalyst](https://millionrounds.com/fund/general-catalyst)
- [Lightspeed Venture Partners](https://millionrounds.com/fund/lightspeed-venture-partners)
- [Valor Equity Partners](https://millionrounds.com/fund/valor-equity-partners)
- [Altimeter](https://millionrounds.com/fund/altimeter-capital)

## Funding history

- August 2026 Series C **$800M**
- July 2025 Series B **$350M**
- January 2025 Series A **$100M**

$1.3B raised across the 3 rounds we hold.

## Reported by

- TechStartups 19 August
- TechCrunch 20 August
- Ventureburn 20 August
- Crunchbase News 21 August

The round's figures come from these reports; each link opens the original.

## Other big rounds that week

[**Starcloud** $250M Series A](https://millionrounds.com/news/rounds/starcloud-series-a-2026-08)[**Muon Space** $250M Series C](https://millionrounds.com/news/rounds/muon-space-series-c-2026-08)[**Callosum** $100M Seed](https://millionrounds.com/news/rounds/callosum-seed-round-2026-08)[**Groq** $350M Series A](https://millionrounds.com/news/rounds/groq-series-a-2026-08)[**Also** $150M Series D](https://millionrounds.com/news/rounds/also-series-d-2026-08)[W **Wispr** $280M Series B](https://millionrounds.com/news/rounds/wispr-series-b-2026-08)

[The company **Castelion on Millionrounds** *→*](https://millionrounds.com/company/castelion)[Weekly roundup **Week of 17 August** *→*](https://millionrounds.com/news/weekly/2026-08-17)[Monthly roundup **August 2026** *→*](https://millionrounds.com/news/monthly/2026-08)

**How this article is made**

We write one for every equity round of $100M or more that at least two sources reported. It is put together from our record of rounds, not rewritten from the reports: the ranks and medians count every equity round we read in the twelve months to the round's date. [How we read rounds](https://millionrounds.com/methodology) · [Report a mistake](https://millionrounds.com/corrections)