UK’s Salience Labs adds $125M series B

Salience Labs, the UK-headquartered silicon photonics company working on optical circuit switch (OCS) technology, says it has raised another $125 million in venture capital support.

The latest tranche, which follows funding rounds worth $11.5 million in 2022 and $30 million last year, was led by Bullhound Capital. It also featured chip giants Intel and AMD via their venture affiliates, plus contributions from a number of earlier investors. Bullhound’s principal Callum Stewart has now joined the Salience board of directors.

“With this new funding, Salience Labs will accelerate the deployment of its optical circuit switching (OCS) technology, scale its volume manufacturing operations and expand its US presence in Silicon Valley as the company continues to transform the networking layer of data center infrastructure,” announced the firm.

Critical networking role

Founded in 2021 out of research initially performed at University of Oxford in the UK and the University of Münster in Germany, Salience has focused on what it describes as “on-memory compute” architecture - something said to combine the lightning-fast speed of photonics with the flexibility of electronics and the manufacturability of CMOS.

CEO Vaysh Kewada, who co-founded the startup with CTO and Münster researcher Johannes Feldmann, said in a release revealing the latest funding round:

“OCS will play a critical role in AI data center networking. As customers roll out optical links in their data centers, high-performance optical switches are needed to deliver the token economics that workloads demand.

“Salience Labs has demonstrated a market-leading technology: a fully integrated on-chip solution that scales well to high-volume manufacturing. This funding, alongside the support of our investors AMD Ventures and Intel Capital, will accelerate our growth into high-volume production to enable world leading performance in AI data centers.” 

The switch architecture is purpose-built to connect thousands of GPUs across multiple racks, thus optimizing scale-up network performance. 

“The investor base and customer relationships Salience has developed really speaks to the capability of the leadership,” added Stewart. “Vaysh has assembled a strong team fully focused on designing a switch architecture that both aligns with customers' near-term roadmaps but also scales with them far into the future.”

Salience is one of a number of companies working on OCS technology, with Spain’s iPronics also recently attracting $125 million in series B support, from Nvidia among others. Earlier this year the Californian startup nEye Systems raised $80 million, with Microsoft and Alphabet among its high-profile backers.

All-optical approach

Along with co-packaged optics (CPO) and near-packaged optics (NPO), the adoption of OCS is expected by the likes of Coherent, Lumentum, and Fabrinet to drive another major uptick in demand for key photonic components.

News of Salience’s series B round comes shortly after the firm’s live demonstration of a 64-port all-optical photonic switch at the ECOC 2026 event in Malaga, Spain, said to be an industry first for a silicon photonics OCS.

“The funding will enable future solutions including 128- and 256- port OCS, unlocking new use cases across data-intensive and performance-critical environments,” stated the startup, pointing to a recent forecast from analyst Cignal AI suggesting that the OCS market will be worth more than $8 billion by 2030.

The all-optical approach espoused by Salience and others is intended to address network and compute bottlenecks while improving efficiency, power consumption, and cost.

Srini Ananth, the managing director of Salience investor Intel Capital, said: “Photonics is quickly becoming essential to scaling AI infrastructure, and optical circuit switching can unlock significant gains in performance and efficiency.

“Salience Labs stands out through its integrated silicon photonics architecture and proprietary optical amplification, addressing key challenges to deploying optical switching at scale.”

Salience points out that it is working with industry heavyweights in the form of Keysight Technologies and Tower Semiconductor to scale its manufacturing operations for high volume.

The startup also plans to build out its Silicon Valley offices and open a second location nearby. “This broader market presence will position the company to capitalize on growing demand for high-performance connectivity solutions in AI data centers,” it suggested.