Olympus 45mm f/1.8 for Micro 4/3
Dang.
I pulled the brand-new cut little Olympus 45mm f/1.8 out of the box, and it had a huge white dust chunk (2-3mm long) behind the front element. Back it goes for a replacement.
I’ve seen dust in many a new lens, but this chunk was as large as I’ve ever come across in a new lens.