Facebook Inc said on Tuesday it would affix labels to political ads shared by users on their own feeds, closing what critics have said for years was a glaring loophole in the company's election transparency measures.
The world's biggest social network has attached a "paid for by" disclaimer to political ads since 2018, after facing a backlash for failing to stop Russia from using its platforms to influence the 2016 US presidential election.
But the label disappeared once people shared the ads to their own feeds, which critics said undermined its utility and allowed misinformation to continue spreading unchecked.
"Previously the thinking here was that these were organic posts, and so these posts did not necessarily need to contain information about ads," said Sarah Schiff, a Facebook product manager overseeing the change.
After receiving feedback, Schiff said, the company now considers it important to disclose if a post "was at one point an ad."
Facebook introduced a similar labeling approach for state news media earlier this month, but that label also sometimes drops off with sharing and does not appear when users post their own links to those outlets.
The company is facing demands to do more to combat false viral information before the Nov. 3 presidential election, including by presumptive Democratic nominee Joe Biden, who last week called on Zuckerberg to reverse his decision to exempt political ads from fact-checking.
Zuckerberg has touted transparency tools in response, arguing that voters should be able to examine statements from would-be political leaders unimpeded.
In a USA Today op-ed on Tuesday, he pledged to display a Voting Information Center at the top of US users' news feeds. He also said the company would aim to help 4 million people register to vote, double its goal for 2016.