Facebook said it would not disclose information about political campaign advertising or related data such as how many users click on ads and if advertising messages are consistent across demographics, despite arguments from political scientists who want the data for research.

Details such as the frequency of ads, how much money was spent on them, where they were seen, what the messages were and how many people were reached would remain confidential under the company's corporate policy, which is the same for political advertising as for commercial customers.

"Advertisers consider their ad creatives and their ad targeting strategy to be competitively sensitive and confidential," Rob Sherman, Facebook's deputy chief privacy officer, said in an interview on Wednesday, when asked about political ads.

"In many cases, they'll ask us, as a condition of running ads on Facebook, not to disclose those details about how they're running campaigns on our service," he said. "From our perspective, it's confidential information of these advertisers."

Sherman said it would not make an exception for political advertising.

Academics who study political campaigns worldwide said this kind of information fosters accountability by analyzing how candidates compete for votes and whether election systems live up to expectations of fairness.