Can spammers get stamps by donating to themselves?
Users receive stamps in exchange for donations to charitable organizations of their choice. Here, care must be taken to guarantee that spammers are not simply funneling payments to a “charitable” organization which they ultimately control. To address this problem, we restrict donations to known reputable organizations which, for example, have been given a Charity Seal from the Better Business Bureau Wise Giving Alliance (bbb.org/charity) or granted non-profit tax status by the U.S. government. • Will legitimate users with extra stamps have incentive to sell them to spammers? For those who make charitable donations, CentMail stamps are effectively free up to the amount of their donations. This creates the possibility of a black market for stamps in which users resell their stamps for potentially far less than their face value. While not inconceivable, this scenario seems implausible since the seller would still be associated with any stamps he sold (i.e., the stamps are traceable to the
