In follow-up answers for Congress, the company said it “only accesses users’ microphone if the user has given our app permission and if they are actively using a specific feature that requires audio (like voice messaging features.)” The Menlo Park, California-based company doesn’t address what happens to the audio afterward.

Source: Facebook (FB) Paid Contractors to Transcribe User Audio Files – Bloomberg

Facebook first started allowing Messenger users to have their audio transcribed in 2015. “We’re always working on ways to make Messenger more useful,” David Marcus, the executive in charge of the service at the time, said in a Facebook post.