Google devices chief Rick Osterloh said he believes anyone "in proximity" of a microphone-fitted smart device like Google Nest or Amazon Echo should be informed the devices are in use.

Osterloh was asked by the BBC whether homeowners should warn guests that their Nest devices could be recording them, and responded that he does so for his own houseguests.

Google Nest devices use microphones and CCTV cameras that monitor sound and movement in a home, recording video and audio.

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Google's Nest smart devices are always listening — their microphones detect loud noises and cameras track sudden movements in a home, and can start automatically recording at any time.

Because of that, Nest owners should probably warn their house guests that they're on camera, according to Google devices chief Rick Osterloh.

When asked by a BBC reporter whether homeowners with Nest have such an obligation, Osterloh first said he hadn't considered it.

"Gosh, I haven't thought about this before in quite this way," Osterloh said. "It's quite important for all these technologies to think about all users... we have to consider all stakeholders that might be in proximity."

Osterloh then acceded that warning houseguests about Nest devices' recording capabilities is proper etiquette, stating that he already does so.

"Does the owner of a home need to disclose to a guest? I would and do when someone enters into my home, and it's probably something that the products themselves should try to indicate," he said.

Nest devices are fitted with an LED light that turns on whenever they're in recording mode. These recordings can't be overridden in the moment, but users can reconfigure their Nest settings to disable all recordings (or simply unplug the devices). A Google spokesperson was not immediately available to respond to Business Insider's request for comment.

Google faced backlash from privacy advocates earlier this year when it admitted that its workers were listening to and transcribing some users' voice commands to Google Assistant. Google said the transcriptions were used to improve its voice-recognition technology and affected less than 1% of all audio snippets recorded.

Google announced expanded Nest features at its annual devices expo Tuesday morning, including Nest Aware, a new cloud network that connects Nest devices. The feature will roll out in early 2020.

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