I just checked the privacy policy and while I'm not a lawyer I would imagine that the following one of the following two clauses would protect them:
"We will share information with third parties who perform services on our behalf. For example, we share information with vendors who help us manage our online registration process or who fulfill your purchases. Some vendors may be located outside of the United States.
We will share information with our business partners. This includes a third party who provides or sponsors an event, or who operates a venue where we hold events. Our partners use the information we give them as described in their privacy policies, which may include sending you marketing communications. You should read those polices to learn how they treat your information."