Salience Labs Secures $125M Series B to Expand Photonic AI Switches

Salience Labs raised $125 million in an oversubscribed Series B round led by Bullhound Capital, with new investors Intel Capital, AMD Ventures, SBI Group, Hudson River Trading and the British Business Bank, and existing backers Applied Ventures, Oxford Science Enterprises, Cambridge Innovation Capital and Silicon Catalyst Ventures also participating. Bullhound’s Principal Callum Stewart joined the company’s board as part of the deal, underscoring the round’s ambition to accelerate the deployment of Salience’s optical switching technology and expand its manufacturing footprint.

The company’s core product is optical circuit switching (OCS), an all‑optical, silicon‑photonic architecture that routes data directly on‑chip between GPUs. By eliminating the electrical‑to‑optical‑to‑electrical conversions that dominate current data‑center fabrics, OCS promises lower latency and reduced power consumption for the massive GPU clusters that drive AI workloads.

Salience demonstrated its first industry‑first 64‑port, all‑optical photonic switch at ECOC 2026, a milestone that the firm says validates its approach and lays the groundwork for denser 128‑port and 256‑port configurations that will support even larger, data‑intensive networks.

The new capital will underwrite high‑volume manufacturing, partnership expansions with Keysight Technologies and Tower Semiconductor, a second West Coast office, and further development of higher‑density switches, positioning Salience to capture a share of the projected $8 billion‑plus optical‑switch market by decade’s end.