Smart TV research finds tracking persists after user opt-out

A study by researchers at Northeastern University has revealed that several smart TV operating systems continue to transmit data to endpoints associated with Automatic Content Recognition (ACR) even after users have opted out of tracking in their device settings.

The research, titled “Watching the Watchers: Privacy Analysis of US Smart TV Automatic Content Recognition,” examined eight operating systems across 12 smart TVs from 10 different manufacturers, including Samsung, Vizio, Roku, LG, and Sony. The study found that network activity resembling ACR—which uses video screenshots or audio clips to measure viewership and serve targeted ads—persisted in certain usage scenarios and even during standby mode.

Lead author Ilgar Mammadov noted that the operating systems tested represent approximately 95 percent of those used in the United States. While the researchers could not definitively identify the specific content being transmitted due to encrypted transfers, they identified self-disclosing domains containing keywords such as ‘acr’ and specific provider names, particularly within Samsung’s Tizen OS.