EYEONE said:
Something about this lens is odd... It just doesn't look right for some reason. I can't exactly put my finger on it but something seems off.
Agreed. Not quite ready to call it a fake, but I'm bothered by the lack of any IR focus markings (although the 100L Macro doesn't have one), and also by the lack of a lens identifier near the end of the barrel. Could it be on the other side? Yes, but that would not be consistent with other lenses. Could it be inside the filter ring? Maybe, opposite the 82mm marking, but I doubt it, because we'd see part of that writing (usually it's three sections at the points of an inscribed triangle - filter diameter, 'Canon EF Lens', and the lens ID). There's plenty of room to print the name distal to the red ring...
The size of the filter ring diameter relative to the lens mount does look appropriate, though. Agree that the other switch would seem to be a zoom lock.
Judging by the distance markings, the lens will have a very short focus throw, much less than the current 24-70mm, might make MF more challenging.