Walmart was granted a patent this week for a new listening system for its retail stores that, if ever deployed, may make some employees and shoppers uncomfortable. According to the filing and claims, it’s “an example system for capturing and analyzing sounds in a shopping facility.” In other words, it’s a kind of surveillance system.

For example, this proposed listening system would be able to detect the rustling of shopping bags and the beeps at a register. Walmart could use this tech as an anti-theft solution to find out if number of items in a transaction and number of bags used checks out. It sounds like a reasonable application of technology in a major retail store, right?

That’s where the intrigue stops and the anxiety begins. The system wouldn’t just be an anti-theft tool, but a way to also monitor employee interactions with customers and possibly monitor what customers are saying in real time about products. “Additionally, the sound sensors can capture audio of conversations between guests and an employee stationed at the terminal,” the patent reads. “The system can process the audio of the conversation to determine whether the employee stationed at the terminal is greeting guests.”

Advanced monitoring systems to track shoppers (and employees) isn’t exactly an original idea. Walmart’s retail rival Amazon has been busy testing its cashier-less Go retail stores for two years now, of which it now has nine locations. Those stores monitor the individual movements of shoppers and employees, all the way down to your gait and physical appearance, to keep track of which items you take off shelves, so Amazon can charge you automatically when you walk out.

Currently, Walmart doesn’t have plans anytime soon to deploy this system in its retail stores. But it does prove that one of the biggest retailers in the world is actively thinking about the future of shopping and retail security. Whether or not your privacy can be preserved in the future while shopping for paper towels is up for debate.