I beat Mercer Frey at the snow elf statue and looted the eyes of the falmer from his body. On other playthroughs, the right eye has been sellable, and the left eye has been a quest item. This time though, I was able to drop the left eye, even sell the left eye, and delvin at the TG has no dialogue to buy it.
Can someone confirm this is not right?
Im on PC so I tried setstage TGLarceny 80, but it didnt kick off the quest.
Any other suggestions?

I'd like to know this too. I'm on PS3 but is there anyway to fix this glitch. If not, I have no problem since I have 2 new decorations and have 150,000 gold.

Maybe you immiedatly sell devin the eye befor eyou continue the thieves guild quest? 1 of 3 playthroughs I sold him the eye but I wonder if a patch broke it?

The first thing i did was to go to delvin to sell the eye, thats how i realised something was wrong.

Bumpity Bump

I sold Delvin the Eye, and was able to recover it off of a shelf behind Brynhoff's desk.

I'm on the Xbox 360 and I sold one eye to Grelka first by accident. I bought it back but then Delvin only took the one eye, should I sell the other one to some random vendor or just hold onto it to see if they fix this in a later patch?

As far as I'm aware, none of the larceny targets are quest items.

As for selling, Delvin has a glitch where he refuses to acknowledge or buy 1 out of them all. So if you did them all up to the eye, then it's the eye that he won't buy.

http://www.uesp.net/wiki/Skyrim:The_Litany_of_Larceny#Bugs

This. For me it was the East Empire shipping map that he wouldn't buy (it wouldn't even trigger a quest when I picked it up).

Delvin buys one but not the other.

This glitched out on me as well. Apparently, when you pick up the left eye of the Falmer, the larceny targets quest completely ends, which makes you unable to hand it to Delvin and hence no dialogue option for it. I really wish Bethesda would fix this soon, because I'm only one item away from completing the larceny collection, and not being able to hand this in irritates the completionist in me.

okay. that makes sense. it made no difference to the 'restoring the TG' part of the questline, it was one of the first larceny items i brought him, and i never got around to finding any more. On the next two characters it was the last thing i brought to him, so if he always refuses the last item, that would explain it. I was still able to become leader, i just put the left eye on the shelf in my house next to the right.

Its the left one he should buy. You can do what you want with the right - hes not interested in it.