Google published the following update in the Google Analytics interface today:
Important update to Remarketing with Google Analytics
Starting May 15, 2017, Remarketing Audiences created in Google Analytics will be enhanced to automatically take advantage of new cross-device remarketing functionality now available in AdWords and DoubleClick. This will allow you to reach your customers across devices when using Google Analytics Audiences.
Our research shows that six in ten internet users start shopping on one device but continue or finish on a different one. With cross-device remarketing in AdWords and DoubleClick, if someone visits your website on one device, you can now reach them with more relevant ads when they search or browse on another device.
Where users have chosen to enable Google to associate their web and app browsing history with their Google account, and to use information from their Google account to personalize ads they see across the web, Google will use data from its signed-in users together with your Google Analytics data to build and define audience lists for cross-device remarketing. In order to support this feature, Google Analytics will collect these users’ Google-authenticated identifiers, which are Google’s personal data, and temporarily join them to your Google Analytics data in order to populate your audiences.
No action is required for these changes to take effect but please review your privacy policies and make any necessary updates to explain what data your business collects and shares with Google.
These changes do not affect your rights to your Google Analytics data, which is still owned by you.
As always, Google users can control their ads experience (or opt out of personalized ads altogether) at My Account.
If you don’t wish to enable Remarketing with Google Analytics, please turn off remarketing data collection.