Lumilens raises more than $700m for optical AI data-centre links

Lumilens has emerged from stealth with more than $700m in new funding, bringing its total raised to over $900m and valuing the company at $5.51bn. The startup is building optical interconnects designed to replace copper wiring in AI data centres, and says its first product is already shipping into a hyperscaler’s live data centres under a deal it describes as worth billions.

The company’s case reflects a broader infrastructure shift: the limiting factor for AI is increasingly how many GPUs can be connected, not just how many can be bought. Large models run across hundreds of thousands of chips that must operate like one computer. A single 400,000-GPU site needs more than 2.4 million optical transceivers, while copper links inside racks struggle at AI speeds because an electrical signal survives about a metre and a half over copper.

The round was co-led by Atreides Management, Bain Capital Ventures, Meritech, Seligman Ventures and Spark Capital, with Qualcomm Ventures and JPMorgan also participating. Lumilens enters a crowded field that includes Nvidia, Broadcom, startups and Chinese rivals such as Eoptolink. Citigroup expects AI infrastructure outlays to pass $2.8tn by 2029, but Lumilens still faces questions around its unnamed customer, unaudited deal value and whether its early deployment can become a durable lead.