While the tech giant states in its policies that it may analyse audio recordings to improve translations, it does not make clear that humans may be listening in, according to web portal Motherboard.
The report claims to have obtained audio recordings which include intimate conversations between loved ones, while others were said to be heard talking about personal issues such as weight loss.
The US technology titan maintained that it gets the permission of customers before collecting their voice data, and takes privacy precautions including stripping away identifying information before sharing it with vendors tasked to help it improve software or services.
“We strive to be transparent about our collection and use of voice data to ensure customers can make informed choices about when and how their voice data is used,” a spokesman said.
The news comes after a series of privacy missteps raised concerns over the future of voice-controlled assistants, a growing market seen by some as the next frontier in computing.