Question about Canon warranty service for 85L (2nd owner)

I recently sold a six month old pristine 85L. There were no issues when I sold it but the buyer received it with a speck inside the rear element. In the cobwebs in the back of my head I recall reading about this type of situation in the past, the general consensus has been a small piece of plastic or other material being left inside the lens during manufacturer that was dislodged during shipping.

My question is this - I recall reading in the past that Canon is only concerned with a copy of the purchase receipt. Do they match that up to the name/address on the repair order? Any advice on how to proceed?

Why not call Canon and ask them?

gasrocks wrote in post #11276529
Why not call Canon and ask them?

Because it's the weekend and Canon phone CSRs have been known to give bad info out over the phone. I've seen discussions on this subject here in the past and would like to hear from those who have submitted gear for warranty work under these circumstances.