Fortell has drawn support from some of Silicon Valley's best-known financiers because it claims to have cracked a problem that hearing aids have struggled with for decades: picking out speech in a noisy room.
The New York startup has raised $163 million at a valuation of about $740 million from Founders Fund, Thrive Capital and Valor Equity Partners, the last led by chief executive Antonio Gracias.
A different approach to sound
Most hearing aids simply turn everything up at once, which leaves wearers straining to follow a conversation in a busy restaurant.
Fortell instead uses artificial intelligence to work out which sounds matter in real time, then turns those up and suppresses the rest.
The approach borrows from the source-separation technology that cleans up a video call, shrunk to run on a custom chip small enough to sit behind the ear.
Building that model took roughly six years, because off-the-shelf designs could not fit the tiny, power-constrained device.
Cracking a five-company market
The pitch lands in an industry critics call stagnant, where five manufacturers make about 97% of the products, insurance will not cover the cost and innovation has been slow to arrive.
Fortell argues that entrenched incumbents had little reason to change, leaving the door open to a newcomer.
The company also points to independent testing, which it says gave its devices the highest overall score and strong marks for understanding speech in noise.
Why investors bought in
The founders carry an unusual pedigree, having come from Butterfly Network, the company that shrank ultrasound scanners into handheld devices.
That record of miniaturising medical hardware helped convince backers the team could do the same for hearing.
One turning point came when Founders Fund quietly invited a friend with severe hearing loss to try an early prototype, and he said he would mortgage his house for it.
Fortell has since launched, made the Forbes Next Billion-Dollar Startups list and sold its $6,800 devices to buyers including the financier Henry Kravis and the comedian Steve Martin.
The road ahead
The devices are so far available only through a handful of appointments, starting at a Manhattan clinic.
The fresh funding is meant to widen distribution and push the product beyond that initial rollout, as Fortell tries to turn a technical edge into a mass-market business.
