We’ve heard plenty of times in the past few years that if you have a smart TV — one that’s internet-enabled, for all that app goodness — that it might be watching you just as much as you watch it. Samsung in particular generates a lot of questions about how secure your data is with your TV, as do LG and Vizio. But there’s a missing piece to the equation. If your TV is watching you, why? Who stands to gain (in the sense of cold hard cash) from your data?

That’s what our colleagues over at Consumer Reports (Consumerist’s parent company) decided to find out.

Your TV is collecting and sending data about everything you watch — TV, streaming content, or discs — to a third party, CR explains. And those three companies have been doing it since as far back as 2012. The process is known as automatic content recognition (ACR), and there’s an entire industry now built on collecting and making money from viewer behavior data.

And the data is indeed valuable, to the right buyers. After all, if the TV is recording everything you watch, isn’t that more accurate and granular than relying on a Nielsen estimate? Content providers would pay well to get to-the-second viewership data.

And of course, there’s endless advertising potential. Companies could buy ad space directly on your TV, bypassing the network level altogether. If you’re watching a TV show with a certain actor in it, why wouldn’t the TV want to try to sell you that actor’s book? Or a movie they were in? Or airplane tickets to the glamorous place they’re visiting?

There are several different companies whose software is embedded into smart TVs. CR names Cognitive Networks, Enswers, and Gracenote as just a few. Those companies monitor the video and/or audio that the user is consuming. The software then captures a “fingerprint” of the content, phones home with it, and a remote server reads the fingerprint and reports back, “That’s Game of Thrones, season 2, episode 4″ or whatnot.

And since all this data does fly back and forth among so many points, it’s leaving a lovely trail of breadcrumbs that adds up to a pretty significant picture of your household’s viewing history, all in the hands of some middleman company (or companies) you’d otherwise never hear of.

Even worse, CR points out, consumers have no real way of knowing what they’re agreeing to when they buy and set up their new TVs. One LG set that Consumer Reports tried had more than 6000 words of legal disclosures to read through in order to be fully informed. The Samsung user agreement spanned 47 separate pages… all of which you can of course agree to with a single click.

The end result? Consumers who are having the most boring and innocuous evening possible, kicking back with an hour of reality TV and a frothy beverage, are being watched and targeted in their own living rooms in ways they may not even realize.

The good news, CR says, is that consumers can opt out. They just have to dig through their TV settings for a few hours to find the right setting first.

Samsung, LG, and Vizio smart TVs are recording—and sharing data about—everything you watch [Consumer Reports]

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