The difference is using a 2nd computing device as a controller it seems, ie using your phone to cast a video to chromecast.
I actually can’t believe touchstream won this initial case though because they are definitely a patent troll. The don’t make any products themselves they just got an overly broad patent of technology that seemingly already existed (and was pretty obvious) and they go around trying to get companies to pay them licensing fees. And what I read of their patent doesn’t even seem like it covers chromecast, they specify a client device -> separate server -> display device not a direct connection to a display device.