Millionrounds

Featured

No. 2October 20263 companiesNever paid for

Cover story

Clay

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

$115MSeries D, led by Wellington Management

  1. 02OpenRouter$113M Series B, 26 open roles
  2. 03Atoms$1.7B Series C
  3. $1.9Braised 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

AIUnited States

The last two rounds

$100MSeries C
Jun 2025
15 months1.1x$115MSeries D
Sept 2026

Led by Wellington Management

$263M across 4 rounds on the record

Why it is worth a look

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

Each line is on the company's record. Check it

OpenRouter

Information technology & servicesNew York, United Statesfounded 2023

The last two rounds

$40MSeries A
Jul 2025
11 months2.8x$113MSeries 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

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

Each line is on the company's record. Check it

Atoms

AIUnited States

The last two rounds

$1.2MPre-seed
Jun 2025
13 months1417x$1.7BSeries C
Jul 2026

Led by Andreessen Horowitz

$1.7B across 2 rounds on the record

Why it is worth a look

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

Each line is on the company's record. Check it

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.

Something wrong? Tell us.

Founders: list your startup. Investors: every company raising now is in Startup Dealflow.