I see now in the pictures that the front element is concave, so apparently it's a design that is different from the classic scheme found in the old 50s. Similarly to how the Zeiss 55/1.8 ZA only has 7 elements in 5 groups, but from the block diagram it looks like an original kind of design, probably explaining its comparatively high price.
EDIT: updated with new (to me, anyway ) info.
EDIT: updated with new (to me, anyway ) info.