You can only activate EDIUS 11 once unlike previous versions. If you want to have a second copy on another machine, for example a laptop, you can buy a second licence using this option. There are second licences available for all the different EDIUS options. Make sure you buy the second licence that matches your original product – i.e. if you bought EDIUS 11 Pro, but the EDIUS 11 Pro second licence.
This licence is if you bought the EDIUS 11 Workgroup upgrade from EDIUS X originally.
If you want EDIUS 11 on a 3rd computer you need to buy another full version.