In the beginning, Samsung TV owners were seeing ads for new streaming content, apps or Samsung products. Owners are now complaining about larger, increasingly obtrusive, and unrelated ads.

Ads in your TV interface
Sometime in 2016 Samsung began pushing a software update to enable ads in the user interface of previously acquired Smart TVs as well as new TVs. The ads were shown above a new icon in the bottom menu.

The move upset some owners of Samsung TVs while others accepted it. Back then, the ads related mostly to new services (such as GameFly), new content from close partners (such as Google Play or Amazon Video), new movies in theaters (such as Angry Birds 2), Samsung's own services (such as TV Plus) or its own products (such as Galaxy smartphones).

Towards the end of 2019, owners have started to voice their dissatisfaction with larger, increasingly obtrusive, and unrelated ads showing up on their Samsung TVs. These include ads for canned beans or discount supermarkets such as the one embedded below or the one shared on Samsung's community boards here.

I own Samsung's $2500 "Frame" art TV and it gets ads in the menus too https://t.co/P2OJ5MkhlW
— Internet of Shit (@internetofshit) March 6, 2020
 

Industry's "largest data set"
On its webpage intended for business partners, Samsung boasts that is has 50 million Smart TVs in operation and that it has the "industry’s largest ACR data set".

What is ACR? It is short for Automatic Content Recognition and it means that the TV uses identification technology to analyze and recognize the content displayed on the screen at any time. It is used to build a personal profile of you and your interests in order to serve "native ads on the home screen" and "video ads on Samsung TV Plus" as well as ads "on the biggest to the smallest screens". In other words ads that venture beyond your TV.

There is apparently no way to deactivate the ads. 

- "In general, the banner cannot be deactivated in the Smart Hub. We thank you for your feedback and assure you that Samsung takes customer feedback into account in product development," Samsung Germany said in response to the tweet.


Samsung is not alone
Samsung is not alone here. In April 2019, Google pushed a new 'sponsored' row to the home screen of Android TV. It affects TVs from Sony and others.

Panasonic has been experimenting with showing ads when you adjust audio volume and European broadcasters have started using HbbTV to serve targeted ads. LG introduced an ad above its webOS menu but it was later removed. Roku is hard at work turning its TV platform into a "next-generation ad platform" while Amazon has been showing ads on FireTV devices for years. Most of these platforms have also been confirmed to use ACR, just like Samsung.

So what is the alternative? Apple's tvOS platform (in Apple TV) does not use ACR and its "ads" are limited to content recommendations from apps such as the Apple TV app. These recommendations can be deactivated and users can remove the app from the top row.

- Source: Job Plas, Internet of Shit, Samsung, Samsung boards, 4KFilme, reddit, AdAge, GitHub