Oratomic raises $475 million Series B as total funding hits $775 million

Oratomic, a Pasadena quantum-computing startup, said it has raised $775 million in total funding since launching in March, including a $475 million Series B that its deal counsel said values the company at $5.4 billion.

What Oratomic announced

On Oct. 8, Oratomic said it has raised a total of $775 million since its March 2026 launch and will use the capital to accelerate work on utility-scale, fault-tolerant machines. The company said ARCH Venture Partners, Spark Capital, Khosla Ventures, Index Ventures, General Catalyst, and Bezos Expeditions led the financing. Oratomic builds quantum computers from reconfigurable arrays of neutral atoms paired with advanced error correction, and it says it is focused exclusively on a fault-tolerant system.

Wilson Sonsini Goodrich & Rosati, which advised Oratomic on the transaction, said the latest round was a $475 million Series B that raised the company's valuation to $5.4 billion and brought cumulative funding to $775 million. The firm described the round as co-led by the same six investors named in Oratomic's release. Oratomic said the money will support growth of its scientific and engineering team, laboratory infrastructure, and the systems required to build its machines.

Independent confirmation

SiliconANGLE independently reported the $475 million Series B and the $775 million cumulative total, and it named the same co-lead group. SiliconANGLE also said the round came about three months after a $300 million Series A and put Oratomic's valuation at $5.5 billion, up from $1.5 billion — $100 million above the Wilson Sonsini figure. The outlet described Oratomic as a California company founded in 2025 that uses neutral-atom arrays.

What is still open

Neither the company release nor the counsel note named customers, disclosed a public-listing plan, or published qubit-count targets for a commercial product. The $5.4 billion and $5.5 billion valuation reads are close but not identical, so this story carries both attributions rather than forcing a single reconciled post-money number.

Context among recent private tech raises

The Oratomic Series B sits in the same private-financing band as other large late-week hardware and infrastructure raises, including Oxide Computer's $445 million Series D. For readers tracking quantum hardware capital, the anchored facts are the $475 million round size, the $775 million cumulative total since March, the six-firm lead group, the counsel-stated $5.4 billion valuation, and SiliconANGLE's nearby $5.5 billion independent read.