Inworld has acquired Ultravox, the Seattle voice AI startup formerly known as Fixie, for an undisclosed sum.
Founded in 2022 as Fixie, the company previously raised $17M to build speech models that handle conversational turn-taking and interruptions. Those features matter for voice agents that must listen, pause and respond like a person rather than transcribing after the fact.
Inworld works on real-time voice technology for AI characters and agents. Buying Ultravox gives it model talent and research rather than just a product, a common pattern as AI companies compete for scarce speech expertise.
Voice has become one of the busiest corners of agent development. Enterprises want assistants that take calls, book appointments and answer questions without sounding robotic, and startups are racing to cut latency.
The deal also reflects consolidation. Many small model shops that raised seed money in 2022 and 2023 are finding standalone growth hard, while larger platforms look to buy teams instead of building from scratch.
For Seattle, it is another exit in a region with deep speech research roots. The question now is whether Inworld turns the acquisition into voice agents that hold up in real calls, where users notice every awkward pause.
