LOS ANGELES — Sam Altman is co-founding Merge Labs, a brain-computer interface startup spinning out of the nonprofit Forest Neurotech and aiming to raise $250 million at a valuation of about $850 million, according to WIRED’s reporting. The pitch is an ultrasound-based system designed to read brain activity without electrodes implanted in the brain, a wager that less-invasive hardware can widen who benefits from neurotechnology, Dec. 22, 2025.
Merge Labs steps out of Forest Neurotech’s shadow
Forest Neurotech has spent the past two years building what it calls a “whole-brain” interface built around ultrasound imaging and stimulation, describing its mission as expanding access to ultrasonic neural interfaces on its website. The new startup borrows that same technical premise but flips the wrapper: a venture-backed company with a Silicon Valley-style war chest, built to chase speed, talent and scale.
In the short term, the fundraising target and valuation remain just that — targets. But the numbers signal investor appetite for brain-computer interfaces even as regulators, ethicists and clinicians continue to debate how to test and govern technology that touches cognition, mood and autonomy.
Why ultrasound, and what’s still unclear for Merge Labs
Ultrasound is familiar in medicine, but using it to infer brain activity and modulate circuits is a newer frontier. In August, Bloomberg reported Merge Labs has also explored a more ambitious hybrid approach involving gene therapy plus an implanted ultrasound device, underscoring how experimental the roadmap could be according to Bloomberg.
Even advocates caution that “less invasive” doesn’t mean “no surgery,” and questions remain about what form factor Merge Labs would actually ship, what data it could reliably capture, and what clinical pathway it would pursue first.
The long runway to this Merge Labs moment
The spinout lands after a steady drumbeat of earlier milestones that made ultrasound BCI feel less like science fiction. In 2023, Caltech highlighted research showing functional ultrasound could enable less-invasive brain–machine interfaces by reading brain activity without implanted electrodes in a Caltech report.
That same year, IEEE Spectrum reported Forest Neurotech would license Butterfly Network’s compact ultrasound-on-a-chip technology as part of an effort to develop an ultrasound-based BCI platform as covered by IEEE Spectrum. And in early 2025, The Guardian reported an NHS-linked trial plan for Forest’s “Forest 1” device — a study designed to test safety and explore whether ultrasound stimulation could help with mood and related conditions The Guardian reported.
Forest’s nonprofit funding base also helped set the stage. Convergent Research announced a $14 million funding commitment to Forest Neurotech in 2024, describing it as an effort to build next-generation BCIs for people with neurological injuries or disease in a Business Wire release.
For Merge Labs, the immediate question isn’t whether investors will fund another moonshot. It’s whether ultrasound can move from promising lab demos and tightly scoped trials to repeatable, regulated products — and whether the company can do it without overpromising what brain data can truly reveal.
