To check, view a black background in the dark with 100% brightness.
or install "Backlight Bleed Test" from the Play Store.
Unfortunately, I don't have a good enough camera to accurately show my bleed. It's primarily in the top left corner with a little along the top edge.
I just upgraded to a Nexus 5 and I am noticing some light bleed while in the dark when my screen is black and the brightness is greater than 40%. I've only noticed it when looking for it, but it's bothering my OCD. I also understand some degree of bleed is normal for LCD panels, but I'm unable to spot it on my friends iPhone. So how severe does your Nexus 5 bleed when displaying black backgrounds in the dark? Please don't say it doesn't bleed unless you've checked.