Salience Labs raises $125M to scale photonic chips for AI data centres
What's the deal? Salience Labs, a UK developer of photonic chips for AI data centre connectivity, has raised $125 million in an oversubscribed Series B round. Bullhound CapitalDealroom has a profile for this one. Try Dealroom → led, with participation from AMD VenturesDealroom has a profile for this one. Try Dealroom →, Intel Capital, SBI GroupDealroom has a profile for this one. Try Dealroom →, Hudson River TradingDealroom has a profile for this one. Try Dealroom →, and the British Business Bank.
Existing investors Applied VenturesDealroom has a profile for this one. Try Dealroom →, Oxford Science EnterprisesDealroom has a profile for this one. Try Dealroom →, Cambridge Innovation CapitalDealroom has a profile for this one. Try Dealroom →, and Silicon Catalyst VenturesDealroom has a profile for this one. Try Dealroom → also joined. Callum Stewart, principal at Bullhound Capital, will take a board seat.
What's the endgame? Salience Labs builds optical circuit switching (OCS) technology to connect GPUs across AI data centres. Its all-optical architecture is designed to link thousands of GPUs across multiple racks, easing pressure on network performance, efficiency, and power as AI infrastructure expands.
The chip design, built on more than a decade of silicon photonics research, targets high-volume manufacturing.
Why now? The round follows the company's demonstration of a 64-port all-optical photonic switch at ECOC 2026, which it calls an industry first for silicon photonics-based OCS. It is also developing 128-port and 256-port switches for larger networks.
"OCS will play a critical role in AI datacenter networking," said Vaysh Kewada, chief executive officer and co-founder. "As customers roll out optical links in their datacenters, high-performance optical switches are needed to deliver the token economics that workloads demand."
Where the money goes: The funding will support deployment of the switching technology, expansion of high-volume manufacturing, and development of next-generation switches. Salience Labs is working with Keysight Technologies and Tower Semiconductor to scale production, plans a second West Coast site in Silicon Valley, and intends to grow its engineering team.
The signal: At $125 million, this Series B sits in the 96th percentile of all UK hardware rounds at that stage. Backing from both AMD Ventures and Intel Capital signals that chipmakers see optical switching as a serious answer to the networking bottlenecks slowing AI data centres.
Read more: Tech.eu
Image credit: Salience Labs
