While most political campaigns solicit personal information from supporters to build mailing lists, privacy advocates said it is not necessary for campaigns to reserve the right to share the data with third parties, as Paul’s website does.

“If a campaign is telling you in a privacy policy that they are reserving the right to hand over the information to third parties, that would be of some concern to me,” said Pat Dixon, founder of the World Privacy Forum. “Because you just don’t know where that’s going. And here in the U.S., you do not have the right to find out where that’s going.”