# Startups worth a look, October 2026

> 3 startups worth a look in October 2026, and the evidence for each: rounds, leads, hiring and filings.

Source: https://millionrounds.com/featured/2026-10 (Millionrounds; every figure on the page links to its filing or article)

Millionrounds

# Featured

No. 2 October 2026 3 companies Never paid for

Cover story

## Clay

Raised $115M in a Series D in Sept 2026, led by Wellington Management.

**$115M** Series D, led by Wellington Management

- 02 **OpenRouter** $113M Series B, 26 open roles
- 03 **Atoms** $1.7B Series C
- $1.9B raised between them in their latest rounds

Next issue 1 November · in 6 days

From the editors

Three companies this month, from an $113M Series B to a $1.7B growth, raising $1.9B between them. They work in ai and information technology & services, and are based in the US. Among those leading their rounds: Andreessen Horowitz, Wellington Management and CapitalG. Three raised again within fourteen months of the round before and one is hiring for fifteen roles or more. Each pick comes with the evidence from the record. Nobody pays to be here.

## [Clay](https://millionrounds.com/company/clay)

AI United States

The last two rounds

**$100M** Series C Jun 2025 *15 months* **1.1x** **$115M** Series D Sept 2026

Led by Wellington Management

$263M across 4 rounds on the record

Why it is worth a look

- Raised $115M in a Series D in Sept 2026, led by Wellington Management.
- That came 13 months after its Series C of $100M in Aug 2025.

Each line is on the company's record. [Check it](https://millionrounds.com/company/clay)

## [OpenRouter](https://millionrounds.com/company/openrouter)

Information technology & services New York, United States founded 2023

The last two rounds

**$40M** Series A Jul 2025 *11 months* **2.8x** **$113M** Series B May 2026

Led by CapitalG

$153M across 2 rounds on the record

OpenRouter is an artificial intelligence infrastructure company founded in 2023 by Alex Atallah, the co-founder and former CTO of OpenSea. Based in New York, OpenRouter has quickly established itself as a leading LLM (Large Language Model) marketplace and AI gateway.

Why it is worth a look

- Raised $113M in a Series B in May 2026, led by CapitalG.
- That came 11 months after its Series A of $40M in Jul 2025.
- Hiring for 26 open roles on its own job board.

Each line is on the company's record. [Check it](https://millionrounds.com/company/openrouter)

## [Atoms](https://millionrounds.com/company/atoms)

AI United States

The last two rounds

**$1.2M** Pre-seed Jun 2025 *13 months* **1417x** **$1.7B** Series C Jul 2026

Led by Andreessen Horowitz

$1.7B across 2 rounds on the record

Why it is worth a look

- Raised $1.7B in a growth round in Aug 2026, led by Andreessen Horowitz.
- That came 1 month after its Series C of $1.7B in Jul 2026.

Each line is on the company's record. [Check it](https://millionrounds.com/company/atoms)

How we pick

Every month the record proposes candidates: companies that just raised, especially from busy lead investors or soon after their last round, whose valuation stepped up in their own filings, that are hiring hard, or whose founders listed them with us. An editor chooses, and every reason is something you can check on the company's page.

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Founders: [list your startup](https://millionrounds.com/list-your-startup). Investors: every company raising now is in [Startup Dealflow](https://millionrounds.com/dealflow).

Every issue

[No. 2 October 2026 Oct](https://millionrounds.com/featured/2026-10)[No. 1 September 2026 Sept](https://millionrounds.com/featured/2026-09)