An Orlando startup that routes light through air rather than glass has quietly pulled together more than $20 million in new financing while landing what may be its biggest customer commitment yet.
Relativity Networks has raised $19.5 million in a SAFE financing and reportedly secured a $40 million follow-on order from a major cloud provider, according to industry reports published Tuesday. The company hasn't confirmed the order figure publicly. What's on the books: an SEC filing from June showing $19.5 million in a SAFE offering that started in January.
If the reported order holds, Relativity would have raised roughly $30 million across six rounds since launching in 2023, per CB Insights. Recent investors are said to include Rhapsody Venture Partners, Bell Ventures and Faster Than Glass, though the company has not publicly disclosed the full investor list for its latest round.
Air-core fiber promises radical speedup
At the heart of Relativity's pitch is ChronoCore, an anti-resonant hollow-core fiber that transmits data through air instead of traditional silica. The physics matter here: propagation speed clocks in at about 3.4 microseconds per kilometer, which Relativity says cuts latency by 32% compared with standard fiber over equivalent distances. That 47% improvement in raw speed could prove critical as artificial intelligence workloads sprawl across distributed data centers that need to stay synchronized.
The technology isn't vaporware. Prysmian, the Italian cable giant, announced in a July press release that high-density ChronoCore cables are shipping now for AI deployments. The two companies ran cable-jetting tests with Dura-Line at speeds reaching 350 feet per minute. Prysmian's Claremont, North Carolina plant produces cables packing 24 hollow-core fibers into a 10-millimeter bundle.
Still, commercializing lab breakthroughs in optics has humbled more than a few startups. Relativity's advantage may be timing: hyperscalers are hunting for anything that might ease bottlenecks in their infrastructure.
Amazon commits to hollow-core across multiple sites
Amazon Web Services is deploying the technology to link roughly 10 data centers, AWS VP of Core Networks Matt Rehder told Fierce Network earlier this year. Supply constraints remain the limiting factor for broader rollout, he noted.
"I will sell every kilometer of fiber I can make," Relativity CEO Jason Eichenholz told the publication. "We have a hyperscaler that wants pretty much everything we can produce."
Eichenholz brings a track record. He previously co-founded Luminar Technologies and earned a PhD from the University of Central Florida. His CTO, Rodrigo Amezcua-Correa, is a professor at UCF's CREOL optics research center, where the hollow-core work originated. Academic pedigree doesn't always translate to manufacturing scale, but the Prysmian partnership suggests Relativity is navigating that transition.
Italian cable maker puts money behind the tech
Prysmian invested in Relativity as part of a $6.1 million seed extension that included GOVO Venture Partners, Prospective Advisors and Zendicate Ventures. The cable manufacturer now runs production lines in Eindhoven and North Carolina under a partnership the companies announced in March.
"A breakthrough fiber technology only matters if it can be manufactured, cabled, and deployed at scale," Amezcua-Correa said in the July release. He didn't need to add the obvious: plenty of optical innovations have died in the gap between prototype and production line.
Fortune reported the startup raised a $4.6 million pre-seed from private investors in early 2025. LinkedIn pegs the headcount at 11 to 50 employees, a range that suggests the company remains lean even as it chases hyperscale deployments.
Crowded field includes Microsoft acquisition
Relativity isn't alone in the hollow-core space. Microsoft bought UK-based Lumenisity in December 2022, a signal that the technology had caught the attention of at least one deep-pocketed buyer. Other players include Lightera (formerly OFS), China's YOFC and Hengtong. Viavi developed what it calls the industry's first bidirectional testing solution for these deployments, reflecting the growing maturity of the market.
Relativity frames ChronoCore as infrastructure for geographically distributed AI training clusters rather than as a simple component play. The company brands its approach the "Scale Across" layer, positioning hollow-core fiber as the connective tissue of what it terms the "AI Geography Era." Whether that messaging resonates beyond the sales deck remains to be seen.
The reported $40 million order from a hyperscaler would mark the largest known purchase commitment for Relativity's technology, though the company hasn't put a name to the customer. If the deployment proceeds as planned, it could validate hollow-core fiber's leap from research curiosity to critical infrastructure. Then again, this is the part where supply chains, installation realities and cost pressures tend to complicate even the best product demos.
Relativity and Prysmian showcased ChronoCore at the Optical Fiber Communication Conference in March. Now comes the harder work of proving the technology can deliver at the scale hyperscalers demand.
