Microsoft contractors are listening to Skype users' sensitive personal conversations in order to operate its AI-powered translation service.
Human workers listened in audio recordings including people talking with their loved ones, discussing relationship issues and talking about personal problems, according to clips leaked to Vice News..
One anonymous contractor also claimed that humans had listened to "phone sex" and pornographic search queries from Microsoft's Cortana virtual assistant.
A spokeswoman for the company said that it always gets permission for examining users' voice data and that users were protected by non-disclosure agreements signed by contractors and by the scrubbing of "identifying" data from voice clips.
It is only the latest report of advanced AI systems turning out to rely on third-party human contractors manually reviewing some users' private communications without widespread public knowledge.
Last week both Apple and Google suspended human reviews for Siri and Google Home after a string of reports exposing the practice. Amazon, notably, continues to use human reviewers for its Alexa voice assistant.
All cases involved some level of sensitive information: Amazon's Romanian contractors said they heard possible sexual assaults; Apple contractors said they overhead people having sex and making drug deals; and Belgian journalists were able to identify Google Home users from a cache of leaked recordings.
Employees of Ring, an Amazon-owned smart doorbell company, also reportedly watched footage from users' doorbell cameras, manually identifying vehicles and people in order to train the AI system.
All three companies said that humans only listened to less than 1pc of voice clips, that the review process was subject to privacy safeguards, and that users had given their permission for the practice. None of the companies explicitly stated that humans would be involved.audio A spokeswoman for Microsoft said: “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.
"Microsoft gets customers’ permission before collecting and using their voice data. We also put in place several procedures designed to prioritise users’ privacy before sharing this data with our vendors, including de-identifying data, requiring non-disclosure agreements with vendors and their employees, and requiring that vendors meet the high privacy standards set out in European law.
"We continue to review the way we handle voice data to ensure we make options as clear as possible to customers and provide strong privacy protections.”
She added that Microsoft vets the privacy practices of all companies it contracts with and has the right to audit them, and that contractors can only access voice clips through a secure portal.
Despite frequent boasts of advanced technology, the AI industry continues to depend on human review. So-called "data labelling", in which raw data such as video or audio clips is manually tagged, lets AI systems learn from their mistakes by giving them positive and negative feedback.