Senator Coons sent Amazon chief Jeff Bezos a letter in May, asking for answers on how long the company keeps records of people's Alexa interactions. In its response, Amazon said it erases transcripts "from all of Alexa's primary storage systems" when users manually delete voice recordings. The company also has "an ongoing effort to ensure those transcripts do not remain in any of Alexa's other storage systems."

However, it will continue to retain certain records, such as when users ask Alexa to subscribe to Amazon Music Unlimited, to place an Amazon Fresh order, to request cars from Uber and Lyft or to make in-skill purchases of digital content. The company also retains Alexa requests for recurring alarm and for schedules like anniversaries and meetings. "[C]ustomers would not want or expect deletion of the voice recording to delete the underlying data or prevent Alexa from performing the requested task," the letter reads.

Amazon has also explained in the missive that it trains Alexa with actual voice recordings and transcripts to help ensure that it works well for everyone. A Bloomberg report from April revealed that the company employs thousands of full-timers and contractors from around the world to review audio clips from Echo devices. Amazon didn't deny that, but it said that it only stores audio if it detects wake words and that it only annotates a small portion of Alexa interactions.

Senator Coons posted his statement regarding Amazon's response, promising to continue working "with both consumers and companies to identify how to best protect Americans' personal information."