Radar-Based Sleep Trackers: Sweet Dreams or Privacy Nightmare?July 25, 2022

It’s no secret that more people than ever are sleeping poorly.  A recent study by the American Academy of Sleep Medicine found that more than half of all Americans have had problems sleeping since the onset of the COVID-19 pandemic. Even independent of the pandemic, an estimated 70 million Americans are believed to suffer from chronic sleep problems.

Sleep tracking devices are a proposed solution to alleviate chronic sleep disorders. These devices monitor one or more aspects of sleep, such as sleep duration, stages, quality, and habits. The sleep monitoring industry is quickly expanding in Silicon Valley and big tech. Such devices are not entirely new to the market: existing sleep monitoring systems are typically incorporated into wearables, such as the Apple Watch and Fitbit, or accessed on mobile devices through apps. Now, however, tracking systems are being implemented into smart home technology.

The emergence of more holistic, sophisticated sleep monitoring systems has been ongoing for at least the last half-decade. For example, Apple acquired the sleep monitoring device and app Beddit in 2017 (which was discontinued in 2022), and Tueo Health, a company developing sleep monitoring systems for children with asthma in 2019.

Amazon’s Alexa can be connected with pre-existing sleep tracking systems. For example, the “Sleeptracker” skill can be enabled in Alexa, connecting her to the Beautyrest Sleeptracker monitoring system, which uses sensors placed under the mattress to collect sleep data.

However, recent trends suggest a movement toward sleep tracking systems that are integrated into virtual assistants and smart home devices. It appears most of the next-generation sleep tracking systems will collect data using radar, rather than just motion sensors or sound recording.

Google was one of the first big tech companies to release such a product. In 2021, Google launched its second-generation Nest Hub with a built-in radar sensor to track sleep micromovements. Radar measures chest movement and other small movements, while microphones assess sleep traits like snoring or coughing. Other built-in sensors can identify ambient temperature and light conditions. All this data is collectively analyzed to provide the user with sleep quality reports and recommendations.

Apple is currently developing a device used to manage health data, specifically sleep-related data. This patent application, filed first in 2020, relates to devices and computer systems for monitoring sleep sessions, wherein sleep data is collected by sensors and/or radar, and sleep-related metrics include time in bed, time asleep, the time of sleep start and sleep end, and audio input.

Similarly, Amazon is developing an Alexa-powered sleep tracking device that relies on millimeter wave radar technology. In July of 2021, Amazon received approval from the Federal Communications Commission (FCC) to make a device that can monitor sleep using radar. The device will be designed to capture “motion in a three-dimensional space to enable contactless sleep tracing functionalities.”

Next-generation sleep tracking technology could substantially improve user quality of life by enabling faster diagnosis of serious sleep conditions and identifying small (but critical) changes that should be made in each user’s sleep environment. Yet at the same time, these devices raise significant privacy concerns. The FCC’s approval of Amazon’s request to monitor sleep raised alarm, with some publications claiming “Amazon wants to use radar so Alexa can watch as you sleep.”

Discussing the developments in sleep tracking devices, Andrew Guthrie Ferguson, a privacy law professor at America University commented, “surveillance as a service has come to sleeping technology, and it’s as creepy as Silicon Valley gets. The privacy of your bedroom is a place that deserves the utmost protection . . . especially from private companies without much regulation or oversight.”

Sleep tracking devices—especially those utilizing radar monitoring—pose a unique challenge for data privacy. On one hand, such devices could be used as life-saving technologies. It is not hard to imagine the use of sleep-tracking systems in hospital rooms or in-home for patients with sleep apnea. Coupled with heart rate monitors, sleep tracking devices could rapidly identify breathing or heartbeat stoppage and automatically notify emergency services. In other words, for some users, the loss of privacy would be substantially outweighed by the benefits of sleep trackers.

On the other hand, sophisticated, radar-based sleep trackers are already available on the market without substantial legal or regulatory protections required for user data. For example, while the California Consumer Privacy Act (CCPA) includes sleep data within the definition of biometric data, it is unclear exactly what is encompassed by the term “sleep data.” The Illinois Biometric Information Privacy Act provides even less coverage: it defines a biometric identifier as “a retina or iris scan, fingerprint, voiceprint, or scan of hand or face geometry” and describes “biometric information” as “any information . . . based on an individual’s biometric identifier used to identify an individual.” Neither laws appear to address the fate of vocalization data, such as users talking in their sleep, or “pillow talk.” There is therefore still a need to exert reasonable controls and protections on sleep data so that those using sleep tracking devices—whether out of necessity or convenience—maintain control over their data and have assurances regarding the security of the same.

Sarah M.D. Luth is an Intellectual Property Attorney in the MVS Biotechnology & Chemical Practice Group. To learn more, visit our MVS website , or contact Sarah directly via email .