Displayports on my dock stopped working so I called up Surface tech support. They wanted to know my SurfaceBook serial nuber but never asked for the serial number of my dock, which I bought on Amazon. After 30 minutes of going through their annoying troubleshooting bull**** (which I already tried multiple times before calling) they shipped me a new dock and told me to keep the old one. So I guess if you don't mind lying to tech support you can get a free dock.