in the "new" sheet:
Insert a new column to the right of B and name it "new legit"
Insert the following formula into cell C2: =if(exact(B2, VLOOKUP(B2,original!B:B,1,TRUE)),"","new")
Autofill the formula to the entire column, or copy and paste the formula
Filter the column, remove blanks
Click OK.
This will now show you exclusively the new Legits you added since the last time you created a report.