If you have a corporate/bulk license account, you have a unique URL that you can share that allows people to sign up without paying. The amount of accounts that can exist under yours is capped – so make sure it’s only shared with people you recognise. You have the ability to remove users you don’t recognise.
To find your unique link or review existing users under your account, visit My Account and click Subscriptions. Click the Sub Accounts button. From here you can search/view existing accounts and find the unique link at the bottom.