Oveit allows you to create private ticket categories that can only be accessed by a private invitation code. Here are the steps you need to take in order to activate this option:
When setting up a new ticket category you will find two options: Public ticket and Private Invitation.
Select Private Invitation and enter the unique code (*use your own private code) that will help your future attendees unlock this new category.
Save the new ticket category.
The registration form will initially display only the Public tickets categories. However, the system will ask if you have an Invitation Code.
A text box for the code will open. The customer needs to enter the code and select the Apply code button.
If the code is correct the private ticket category will become available for registration.
p.s. you can create multiple private ticket categories, each with its own invitation code. The code will unlock just the category associated with it.