Hi John,
Contact fields are only automatically filled in (or pre-populated) when the invitee accesses the event through a data tag in a Cvent email or, if the option is enabled, a public weblink. Within your invitation email, if you have the RSVP Yes data tag in there, it will populate with the information of who the invitation was sent to when you click to register from it (when it is forwarded to someone else as well.) You can replace the data tag with the registration weblink instead and it will not prepopulate as long as you have the pre-populate setting turned off.
You may want to explore using the actual forward invitations feature as well for tracking who people are forwarding invitations to: Using Invitation Forwarding
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Julia Plymack
Senior Customer Success Manager
Cvent
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