SAN FRANCISCO (Reuters) – Thousands of UK political ads went missing from Facebook Inc’s (FB.O) searchable advertising database on Tuesday, hampering researchers’ ability to track ads two days before Britain’s general election.
A British political Facebook ad, one of many missing from Facebook’s searchable advertising database, is seen in this December 10, 2019, screenshot from social media. Facebook/via REUTERS
Facebook’s ad library, which it launched in the UK in 2018, is a public tool for users to view political advertising on the platform.
The problem, first reported by Sky News, affected ads from the ruling Conservative Party, the Brexit Party and the Liberal Democrats. It was not immediately clear if any Labour Party ads were affected.
“We have fixed the bug and all of the impacted ads in the UK are now back in the ads library,” Facebook said in a statement.
A spokesman also confirmed that some ads in the United States were affected, but declined to answer questions on the scale of the issue there.
Facebook’s ad library has been a cornerstone of the social media giant’s efforts to be more transparent about its role in elections, but researchers say it is poorly maintained and fails to provide detailed targeting data – for example, how political advertisers target UK voters geographically.
Tristan Hotham, a research consultant with WhoTargetsMe, an advocacy group that tracks digital political advertising, called the ads’ effective disappearance “a catastrophic failure.”
“If you’re a researcher you expect to be able to go back