Facebook brings back reach estimates for Custom Audiences

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.

Why we should care

Reach estimates were a handy tool for advertisers, making it possible to determine approximate campaign sizes and manage budgets and bidding activity accordingly — without taking up a lot of time and effort on their part.

“When thinking of the last year, the absence of the product didn’t impact the way we crafted and developed strategies, but rather impacted the precision of our strategies,” said 360i Vice President of Paid Social Strategy Lead Phillip Huynh. “Instead of having more precise reach estimates, we often used proxies on our end that needed to be monitored closely to ensure that we didn’t over-under saturate the market,” he added.

Huynh said the reintroduction of reach estimates will allow his agency to activate “closer” to the data they planned against — a boon for both brands and brand audiences on the platform as it helps deliver more relevant ads.

“We’re really excited about having this brought back to the platform as the reach estimate tool allows us to plan more efficiently and effectively,” said Huynh, “It does this by giving us a clear understanding of the size of our audiences on the buying platform, which helps inform ideal budgets and bids.”

More on the news

• When Facebook first announced the reach estimate vulnerability last year, the company said it did not believe the tool had been used maliciously.
• Since removing the tool, Facebook has been working with the researchers who notified the Facebook’s Bug Bounty program that the reach estimate tool could be exploited, along with its Business Integrity team.
• To resolve the issue, Facebook said it has added complexity to the rounding logic for reach estimates and improved back-end detection processes to surface potential misuse.

About The Author

Amy Gesenhues

Amy Gesenhues is a senior editor for Third Door Media, covering the latest news and updates for Marketing Land, Search Engine Land and MarTech Today. From 2009 to 2012, she was an award-winning syndicated columnist for a number of daily newspapers from New York to Texas. With more than ten years of marketing management experience, she has contributed to a variety of traditional and online publications, including MarketingProfs, SoftwareCEO, and Sales and Marketing Management Magazine. Read more of Amy’s articles.