You have the option of treating all rehired employees as new hires by completing a new Form I-9 and creating a case in E-Verify. However, you also have the option of completing Section 3 for all rehires and only completing a new Form I-9 and creating an E-Verify case if you rehired employees who didn’t have a previous E-Verify case or if you created a case and did not receive a result of employment authorized.
For more information see Section 2.1.2 Rehires in the E-Verify User Manual.