How to Filter New Leads in Clay Using Existing Data from Table A

Hey guys! I am curious if I can achieve this with Clay: -Lets say I have existing set of leads on employees from company ABC (Master-Database) I have stored it in Table A inside Workbook ABC -I have new sourced a new set of leads from Clay they're imported in another table(Table B) Is there a way that I can make sure that table B only contains new leads by checking the existing ones from table A? Thanks a lot!