Within Uptics you are free to use our ZeroBounce Email Validation service or not. If you are importing already validated lists into Uptics, a point to note here is that our system will not recognize if your contact lists are validated prior to the import or not, and if you have the Email Validation settings turned 'ON' within the system, the emails will be validated on importing the contacts.

Hence, you would want to make sure your Email Validation setting toggle is turned 'OFF' as shown below prior to importing a pre-validated contact list.