Update comes as Apple halts Siri listening, and Amazon gives opt-out option with Alexa
The computing giant joins Apple, Amazon, Google and Facebook, who in the past couple of weeks have all been found to have hired contractors to listen to recordings of their users.
This listening, which only happens to select few conversations between users and voice assistants or translation tools, is conducted to help the companies improve these technologies.
First spotted by Motherboard, the updated policy now states how Microsoft collects personal data to "improve and develop our products." It then adds: "Our processing of personal data for these purposes includes both automated and manual (human) methods of processing."
Microsoft later says that, to build, train and improve its artificial intelligence (in those cases used to translate Skype calls and run the Cortana voice assistant), it will "manually review some of the predictions and inferences produced by the automated methods against the underlying data from which the predictions and inferences were made.
"For example, we manually review short snippets of a small sampling of voice data we have taken steps to de-identify to improve our speech services, such as recognition and translation."
The policy now states: "To help the translation and speed recognition technology learn and grow, sentences and automatic transcripts are analyzed and any corrections are entered into our system, to build more performant services. This may includes transcription of audio recordings by Microsoft employees and vendors".
In a bid to protect user privacy, Microsoft says it takes "steps to de-identify data, requiring non-disclosure agreements with vendors and their employees, and requiring that vendors meet the high privacy standards set out in European law and elsewhere."
Along with the changes to its privacy policies, Microsoft issued a statement saying: "We realized, based on questions raised recently, that we could do a better job specifying that humans sometimes review this content."
As with other technology companies caught up in this story, the issue lies with Microsoft initially not stating that humans sometimes listen to voice recordings. The "review" process - described by Apple as "Siri grading" - isn't something consumers should be expected to understand, or link to the idea that 'manual' means 'humans are listening'.