Salience Labs has raised an oversubscribed $125M Series B led by Bullhound Capital, with AMD Ventures, Intel Capital and the British Business Bank taking part. The Oxfordshire company will use it to scale manufacturing and open a second West Coast office.
An Oxfordshire photonics company has raised $125M to build optical switches for AI data centres. The research is British and German, part of the money is British state money, and the expansion is in California.
Bullhound Capital led the oversubscribed round, with AMD Ventures, Intel Capital, SBI Group, Hudson River Trading and the British Business Bank joining, the company said.
Salience Labs was founded in 2021 and sits in Milton, Oxfordshire. It is built on more than a decade of research at the University of Oxford and the University of Munster.
Its product keeps light as light. A conventional switch converts an optical signal to electrical form to route it, then back again. Optical circuit switching establishes a path for the signal itself.
It showed a 64-port all-optical switch at ECOC in September, after launching a 32-port version in the spring that Keysight validated, SDxCentral reported. The unit fits a standard 1U box.
Nvidia is not in the round, and no customer is named. The 128 and 256-port switches the money is meant to fund have no date.
A British rival is further along on less. Oriole Networks is deploying its optical circuit switching platform in the UK government’s £50M ARIA lab alongside AMD chips, having raised about $35M in total.
AMD’s own roadmap supports both copper and optical links in its MI500 GPUs, extending in 2027. That is AMD’s plan rather than an order for Salience.
The money here runs much larger. Lumilens left stealth in August with more than $700M at a $5.51bn valuation, already shipping into a hyperscaler’s live data centres.
The prize explains it. Dell’Oro expects cumulative spending on switches in AI back-end networks to approach $1T across 2026 to 2030, more than half of it scale-up.
The pattern is familiar. PhotonDelta opened a Silicon Valley hub in 2024 to link Dutch and American photonics, two years after €1.1bn of Dutch state money.
Salience already has an engineering team in California and a chief executive splitting her time. This round funds a second West Coast office, and no customer, deployment or qualification date has been disclosed.
British policy is pulling the other way. The technology secretary said in June that the government would buy AI chips from British firms to stop them leaving for the US, after Graphcore and Alphawave went to foreign buyers.