Google sent an email to AdSense, AdMob and Ad Manager users saying they are “launching support for programmatic bidding on inventory eligible for Limited ads.” Limited ads (LTD) give publishers the ability to serve ads in a limited way. Limited ads disable the collection, sharing, and use of personal data for personalization of ads.

Google announced this over here too, “In the first quarter of 2024, Google will launch support for programmatic bidding on inventory eligible for limited ads. A publisher can enable this new serving mode to make use of invalid traffic detection-only cookies & local storage on both consented and un-consented traffic to enable demand from Google demand and Authorized Buyers in limited ads.”

“This new serving mode will allow for contextual programmatic demand when publishers are serving Limited Ads, and enables demand from Google Demand, Authorized Buyers, Open Bidders, & SDK Bidding,” the email adds.

Google said that if you decide to use limited ads serving mode, Google will make use of invalid traffic detection-only cookies & local storage regardless of the user consent signals passed with Limited ads requests.

Here is the text of this email:

As explained here:

The browser’s Trust Token API may be accessed to help defend against fraud and abuse. Google does not require publishers to obtain consent for this use case.
Ad-serving technologies (our JavaScript tags and/or our SDK code) will still be cached or installed as part of the normal operation of users’ browsers and mobile operating systems, and ad creatives will still be sent to, and in some instances cached on, devices. Data like IP addresses will still be used in the course of basic ad serving.
Invalid traffic detection-only cookies & local storage will be used to help defend against fraud and abuse and Google does not require publishers to obtain consent for that.

Publishers that do not want to use invalid traffic-only cookies and local storage without user consent should opt out of this feature by turning it off in the AdSense user interface.

Limited ads are turned on by default and can be turned off at any time. Complete the following steps to turn off limited ads:

(1) Sign in to your AdSense account.
(2) Navigate to Brand Safety and then Blocking controls and then Ad serving.
(3) Turn off Limited ads.

Turn on limited ads (once this feature is available)

Complete the following steps to turn on bidding for limited ads if it was previously turned off:

(1) Sign in to your AdSense account.
(2) Navigate to Brand Safety and then Blocking controls and then Ad serving.
(3) Turn on Limited ads.

Here is a copy of the email Google sent me via AdMob:

Here is more details on limited ads.

There is a lot of confusion around this, I am confused also.

Forum discussion at WebmasterWorld.