No. In the case of a standard or academic retail package, only one person can be listed as the owner of the software. Writing partners cannot co-own a copy of Final Draft any more than they can co-own an airline ticket.
The standard Final Draft retail package comes with two activations, but these are for the registered user's desktop and laptop, home and office, or city home and country home. The second activation is not to be used by another person.
These terms are per the End User License Agreement, which you agreed to when you installed the program.
If you own a copy of Final Draft and your writing partner needs one, have them contact our sales department here: