I got a phone back from an employee and he couldn't remember his Apple ID password, how do I get the phone open?

If they forgot the Apple ID (iCloud) password, enter the Apple (iCloud) ID, and click Forgot Password. See if they can get a Rescue or Notification email option if necessary. Link to contact Apple Support at the end of the 2nd article.

Apple ID - Manage  -     

Apple ID – Forgot Password  *      

Firecause wrote:

I had an employee return his iPhone, but he can't remember his Apple ID password. How do I clean the phone for use?

Said employee need to reset his apple id password.