Salience Labs raises $125m Series B for photonic AI data centre chips
British Business Bank joins oversubscribed round backing optical switching startup's manufacturing push.
Salience Labs, a developer of photonic chips for AI data centre connectivity, has raised $125 million in an oversubscribed Series B funding round. The money will go towards scaling up the company’s optical switching technology and expanding its manufacturing operations.
The round was led by Bullhound Capital, with participation from AMD Ventures, Intel Capital, SBI Group, Hudson River Trading and British Business Bank. Existing backers Applied Ventures, Oxford Science Enterprises, Cambridge Innovation Capital and Silicon Catalyst Ventures also took part. Callum Stewart, Principal at Bullhound Capital, is joining Salience Labs’ board as part of the deal.
What Salience Labs makes
The company builds optical circuit switching (OCS) technology intended to improve the connectivity between GPUs in AI data centres. Its all-optical switching architecture is designed to link thousands of GPUs across multiple racks, a problem that is becoming more acute as AI computing infrastructure grows and puts pressure on network performance, efficiency and power consumption.
Salience Labs says its chip architecture draws on more than a decade of research in silicon photonics and is designed for high-volume manufacturing as well as deployment across AI data centre infrastructure. CEO and co-founder Vaysh Kewada said OCS will play a critical role in AI data centre networking, adding that as customers roll out optical links in their data centres, high-performance optical switches are needed to deliver the token economics those workloads demand. She said the company has demonstrated a fully integrated on-chip solution that scales well to high-volume manufacturing.
Recent milestones and what comes next
The funding round follows Salience Labs’ demonstration of its 64-port all-optical photonic switch at ECOC 2026, which the company describes as an industry first for silicon photonics-based optical circuit switching. It is also developing 128-port and 256-port switches aimed at larger networks and other data-intensive applications.
To scale manufacturing, Salience Labs is working with Keysight Technologies and Tower Semiconductor. The company plans to expand its presence in Silicon Valley with a second West Coast location and to enter additional geographic markets. The new capital will support deployment of its optical switching technology, expansion of high-volume manufacturing, further product development including next-generation switches, and growth of its engineering team.
What it means for the UK
The involvement of British Business Bank alongside Oxford Science Enterprises and Cambridge Innovation Capital, both existing investors, underlines a continuing pipeline of UK institutional and university-linked capital backing deep tech spinouts with silicon photonics roots. An oversubscribed $125 million Series B, with participation from US chipmakers AMD Ventures and Intel Capital as well as trading firm Hudson River Trading, signals international demand for UK-originated photonics technology aimed squarely at the AI infrastructure build-out.
For Salience Labs, the round gives it the capital to move from demonstration hardware, such as the 64-port switch shown at ECOC 2026, towards volume manufacturing and a broader product range spanning 128-port and 256-port switches.
What to watch next
Watch for progress on the 128-port and 256-port switches, further details of the Silicon Valley expansion, and how the manufacturing partnerships with Keysight Technologies and Tower Semiconductor translate into shipped volumes for AI data centre customers.