Always add 360 , PS3 , or PC to clarify which system the bug appears on.
PC 360 PS3 If the statue is the last larceny target needed to turn in, Delvin Mallory will not accept it, along with any others in possession.
After giving the statue to Delvin Mallory, it will be placed on a shelf in the Thieves Guild. The Dragonborn can, in turn, steal the statue back. However, it is impossible to drop or sell the statue because the game refers to it as a quest item, even though the quest has been complete.