This will apply to shared Custom Audiences that have been uploaded from a customer file.
Users will be able to select a "Why am I seeing this" option, which will reveal the name of the business that uploaded their data, as well as who they have shared the Custom Audiences with.
Facebook has come under attack due to concerns regarding the privacy of users' information, such as in the case of Cambridge Analytica, which was accused of illegally storing millions of users' data.
In December 2018, Facebook shares dropped after a New York Times report said that the social media giant had allowed over 150 companies to access more of its users' personal data than it had disclosed.
In response, Facebook has pledged to focus on improving transparency in ad targeting.
