Sift Science links users based on Device ID as well as other features such as Cookie Fingerprint, IP address, Billing/shipping address, and more! A graphical view of how a user is connected to other users can be found in the Network view of the User Details page in the Console. Here is an example from our demo environment:
You can also get device information through our Device Fingerprinting API. This gives you information like the first time you’ve seen the device and how the Sift Science network has labeled users on that device. From there, you can block fraudulent users from coming back to your site. You can view information on Device ID integration here.