basically in areas that are supposed to be in complete shadow (such as the curve where the back of the chair and base connect in the third image) there will be a strange sliver or area of light that does not make sense. Same with a similar object in picture 4 where the arm rest connects to the base there is a triangle of light that is supposed to be in shadow.

both objects are fairly simple meshes that only consist of a single mesh and should not have any problems. near clipping isn't the problem.