Those are the major signs, more specifically the tabs by the swoosh on the toebox and the direction of the mesh at the toe box (should be almost entirely vertical, fakes have the holes going at an angle) . There are two main companies making them. One of them gets the tab location right but the mesh is all off, and one gets the mesh right but the tab location is way off. I have seen a couple retail pairs that have weird tab placement, but the majority don't. The fakes have gotten pretty good with the dots on the sole though, so just keep an eye on the tabs and mesh.