Facebook is reinstalling reach estimates for Custom Audiences, a tool that allows advertisers to estimate audience size for their Custom Audience campaigns. The company removed the tool in March, 2018 when researchers at Northwestern University discovered a vulnerability that made it possible to infer attributes of Facebook users via the tool.
“People’s privacy is incredibly important to Facebook and we take any potential abuse of our service very seriously,” said Facebook Director of Product Management Mary Ku, “Last year, when researchers found this issue, we suspended it and after working with those researchers to address the issue, we are now reinstating it.”
Facebook reports it worked on three key changes to improve security around its Custom Audiences reach estimate tool: privacy, detection and new restrictions. The new restrictions include Custom Audience rate limits — the number of audiences or API calls an account can have. The newly introduced rate limits have been designed to limit potential misuse and will not impact most advertisers, according to Facebook.
Source - Read More: marketingland.com