I have a U3011 that is still under warranty and I noticed today while cleaning my screen that I couldn't remove some marks. It appears that the marks are not actually on the surface. If I move my head around it looks like the marks are behind the pixels and they are equivalent in size to quite a lot of pixels.
I ran the LCD Conditioning function for about an hour and nothing changed. So then I ran the built-in diagnostics and took some pictures. The serial number is MX-0PH5NY-74446-19M-068L.
