Seeed Studio has issued a new Seeed Design for Manufacturing Manual. For their pick-and-place machines, they require some new, very specific fiducial marks. See section 11.2.1:
It’s a 1mm copper circle surrounded by a 2mm hole in the solder mask. That, in turn, is surrounded by a copper octagon. They say “covering copper”, but I think they mean “covered copper”, under the solder mask.
I’ve tried making this in the footprint editor. Each octagon face is a trapezoidal SMD pad, and the octagon is a circular array of such pads. The problem is that that they’re pads to KiCAD. Even if I blank out the pad number, they’re treated as real pads - the solder mask doesn’t cover them, and design rule check complains that the pads are touching each other, which they are… Is there some way to tell KiCAD that this is non-functional copper? Thanks.