Who can create a user in multiple companies?

• Only Admins or Staffing Users with access to multiple companies in Recruiting can manage users in those companies.
• An organization might be using multiple instances in Recruiting for a parent company with subsidiaries or even different branches inside the same company. Employees can be given access to specific instances.

How do I add a user to a different company?
First, the employee must have a Recruiting account. 
Next, access the user's account settings via Admin > Users.
Click Add Companies and assign the user to the right instances.