Facebook-parent Meta on Tuesday said it will stop letting ads be targeted at users based on "sensitive" topics such as race, religion, sexuality or political party, citing concerns about abuse.
The company's deep knowledge about its users' interests is prized by advertisers looking to reach a certain audience -- and is an engine of its multi-billion dollar ad business -- but could be used to influence or exclude groups.
"We want to... address feedback from civil rights experts, policymakers and other stakeholders on the importance of preventing advertisers from abusing the targeting options we make available," Meta vice president of ad product marketing Graham Mudd wrote.
He noted the change was not based on people's actual characteristics but on things like how users interacted with content on the company's platform.
Starting on January 19, apps in the Meta family will no longer offer advertisers the option to target people based on their interest in causes, organizations or public figures related to health, race, ethnicity, political affiliation, or sexual orientation.
Examples include things like lung cancer awareness, same-sex marriage, the Catholic Church, Jewish holidays and political beliefs.
High-profile misfires of ad targeting on Facebook include promotions of military gear served to far-right militia groups before the January 6 storming of the US Capitol by supporters of then president Donald Trump.
US housing officials also sued Facebook in 2019 over allegations landlords and brokers were allowed to improperly restrict housing ads "to exclude people of color, families with children, women, people with disabilities".
However, there may be some secondary effects for non-profit groups seeking fundraising or small companies looking for customers.
"The decision to remove these detailed targeting options was not easy and we know this change may negatively impact some businesses and organizations," Mudd wote in a blog post, adding thousands of options would be impacted.
Announcement of the ad-targeting tweak came as Facebook battles one of its worst crises ever -- the leak of reams of internal documents to US lawmakers, regulators and reporters by former employee Frances Haugen.
Haugen brought her arguments to key lawmakers in Brussels this week after giving testimony in Washington and London and ahead of a stop in Paris.
The EU is currently pushing through new laws that could force the world's biggest tech firms to rethink the way they do business.
Facebook has said Haugen's allegations distort reality and described her as a mid-level engineer with limited access to important decisions.