Custom Audiences update: No more 'scraping' Facebook user IDs

Facebook has recently updated its Custom Audiences terms of service, preventing the “scraping” of Facebook user IDs for ad targeting.

Through Custom Audiences, advertisers can target ads based on email lists, phone numbers, website visitors, Facebook app user IDs and mobile app users. However, many advertisers gamed the system by uploading email lists of those who weren’t customers, those who didn’t use the company’s Facebook app or hadn’t opted into the company’s service, as well as targeting the user IDs of groups and pages to break into new targeting groups.

This practice, though effective, ran counter to Facebook’s Custom Audiences terms of service.