Salience Labs raises $125m to scale optical switches and expand in California

Salience Labs has raised an oversubscribed $125 million Series B to scale manufacturing of its optical switches for AI data centres and expand its California operations, including a second location near its existing Silicon Valley offices.

Bullhound Capital led the round, announced on October 14, with participation from AMD Ventures, Intel Capital, SBI Group, Hudson River Trading and the British Business Bank. Existing shareholders including Applied Ventures, Oxford Science Enterprises, Cambridge Innovation Capital and Silicon Catalyst Ventures also participated. Bullhound principal Callum Stewart is joining the board.

The financing links a British research-led hardware business more closely to the US semiconductor ecosystem. Salience already has an engineering team in California, according to The Next Web, and chief executive and co-founder Vaysh Kewada splits her time between locations. This is an expansion of an established US presence, rather than a first market entry.

From European research to higher-volume production

Founded in 2021 and based in Milton, Oxfordshire, Salience draws on more than a decade of research at the University of Oxford and Germany’s University of Münster. Kewada co-founded the company with chief technology officer Johannes Feldmann, a Münster researcher. Earlier funding rounds brought in $11.5 million in 2022 and $30 million in 2025, according to optics.org.

The new capital is intended to move the business towards higher-volume production while funding larger switches. Salience demonstrated a 64-port all-optical photonic switch at the ECOC industry event in Málaga in September, following a 32-port product launched in the spring. Its roadmap includes 128- and 256-port versions, but launch dates have not been disclosed.

Salience says it will continue working with Keysight Technologies and Tower Semiconductor as it scales manufacturing. The funding announcement does not specify where additional production capacity will be located, so the California office expansion should not be read as an announcement of a US factory.

Targeting the network between AI processors

Salience’s technology addresses the connections between processors, rather than replacing the processors themselves. Conventional switching converts optical signals into electrical form for routing and then back into light. Optical circuit switching establishes a path for the light signal itself, aiming to reduce conversion overhead and improve network efficiency.

The company says its integrated architecture is designed to connect thousands of graphics processing units across multiple racks. That matters as AI infrastructure grows: faster chips cannot deliver their full benefit if communication between them becomes a bottleneck. Networking performance increasingly affects how efficiently expensive computing capacity is used.

“AI infrastructure is increasingly being designed at rack scale, where networking has a direct impact on system performance, efficiency and economics,” Patrick Rundell, director at AMD Ventures, said in the funding announcement.

The potential market is substantial, though broader than Salience’s particular technology. The announcement cites Dell’Oro Group’s forecast that cumulative spending on switches for AI back-end networks will approach $1 trillion during 2026–2030. That is not a forecast for optical circuit switches alone, nor a measure of revenue available to Salience.

A larger US footprint, with commercial milestones still ahead

Expanding in Silicon Valley supports Salience’s stated strategy of engaging customers and partners while developing production hardware. Backing from AMD Ventures and Intel Capital adds semiconductor-industry investors to that effort, but investment should not be confused with a purchasing commitment.

Competition is already moving towards deployment. The Next Web reports that British rival Oriole Networks is deploying its optical circuit switching platform in a UK government ARIA laboratory alongside AMD chips, having raised about $35 million.

Salience has not named a customer or disclosed deployment or qualification dates. Its next test is therefore not simply opening another California office: it is converting demonstrated European photonics technology and a much larger funding base into qualified products, repeatable manufacturing and commercial installations.