This is AR coating delamination. Once it starts, any amount of moisture to the lens will cause the AR coating to continue to flake off. The lens looks like it's still useable - I would just remove the rest of the AR with some tape. This type of delamination only occurs with PBI and C6 OEM lenses (as they had backside AR coating).I had something similar happen to a set of OEM PB1 lenses overnight, but doesn't look like the same kind of delamination that the OP's lenses had. Recently got them with a PB1 Matte that I bought, they were wearable, not perfect, maybe 7/10, and totally clean when wearing. Last Thursday they were fine, and Friday morning, see pics below to what happened on the inside. What's weird is that when I put them on, I can't notice anything wrong.
Has anyone seen this happen? How or why does this happen?
View attachment 678365View attachment 678366View attachment 678368