When we discuss owning a SideDrawer it's important to understand if you're talking about the SideDrawer account (the license holder) or the actual, "physical" SideDrawer (with all the tiles, records, files and documents within). It's possible to own the license and not the "physical" SideDrawer.
When you sponsor someone, you’re purchasing a premium SideDrawer license and then creating a SideDrawer for your client to use. After you create it, your sponsored client will receive a Welcome email with a link to sign up and create a SideDrawer account and the premium SideDrawer license you purchased is attached to that link.
So, to put it simply, to sponsor a client you create a SideDrawer for your client and assign it a license. Your client creates a SideDrawer account using the email that's automatically generated and their SideDrawer account is paired with the SideDrawer you made for them. The client can keep the SideDrawer but the license can be removed by you.
Because you both have Premium licenses you'll have access to all the great features and like being able to share important documents and files by uploading it to records created in their tiles (that's provided they don't change viewing permissions of course.)
If, at any time, you wish to regain a license to a SideDrawer you’ve given someone to use, you can remove the license to their SideDrawer and add it back to your account. That user will be converted to a free account and they’ll have the option to upgrade to a premium license.
For more information on how to remove or revoke a SideDrawer license, click here.