Amazon Prime freeloaders, you're about to get the boot. Over the weekend, Amazon updated their Prime rules to reduce the number of people you can share accounts with from four to one.
A feature called Amazon Household is absorbing the original Prime shipping sharing feature, and so now Prime account sharing will also now make all credit cards and other account information available to both adults, which is presumably fine for families, and less so for friends and roommates.
Each account can have up to four "child" accounts to allow access to a "family library" of books and media.
As of now, the change affects new and up for renewal accounts only.