Helix Raises $6 Million for On-Device Voice Checks That Tell Humans From Bots

BAM Ventures, Aglaé Ventures, Corazon Capital, Tusk Ventures, Yonder Ventures, Rule30 and Brown Alumni Group also took part.

The company is aimed at a problem that AI agents are making harder: telling people from software online. Chief executive Alex Oberg told TechCrunch that internet identity has always relied on proxies such as email addresses, phone numbers, IP addresses and device fingerprints, and that AI makes those proxies less reliable. Helix's model runs on the user's device and, the company says, works even on an iPhone 13, which keeps deployment costs low and avoids sending recordings to a server.

The startup is pitching the product as a replacement or supplement for CAPTCHA and as a defence against bot attacks. It also sees a market in age verification, as social media rules around the world push platforms to collect identity documents or face scans. "It's a four-second voice challenge," Oberg said, arguing that users should not have to trade privacy for child-safety compliance.

One customer, in-home healthcare provider Zeel, uses Helix to verify the identity of practitioners visiting patients' homes. Oberg said verifying workers such as cab drivers is another use under consideration, and the company is running pilots on whether voice can signal conditions such as drunkenness or distress.

Oberg was also clear about the limits. He said the technology cannot reliably detect lying, does not identify individual speakers, and that any stored voiceprint cannot be used to reconstruct a person's voice. Helix does not yet believe it can reliably detect AI agents during live phone calls, according to the report.

Helix was founded in 2025 by Oberg, Anna Dorofiyenko and Mike Hall. Oberg previously sold a startup to Ticketmaster and worked on its Verified Fan anti-bot system; Dorofiyenko led data science teams at Live Nation and Zillow; and Hall worked at Nike and at Tinder, where he helped build its first matching algorithm.