AutoCAD Inventor :: Yellow Surface Edges

We just upgraded Inventor from 2013 to 2014.

I opened a model generated in previous releases and noticed that there were parts with a strange yellow highlight. 

Turns out the parts aren't explicitly highlighted, it's just that their edges are yellow. See the screenshot below.

I usually work in the 'Shaded with Edges' view style. I found that if the view style is changed to 'Shaded' or 'Realistic', the yellow disappears with the edges.

The only parts the yellow edges seem to affect are ones generated as surfaces. I would like to know how to turn the yellow off is possible. So far I've tried changing the part appearance in the toolbar and changing the surface body properties in the model tree; neither method worked.

Now I don't model in surfaces, but there have been purchased parts imported into Inventor that have in the past ended up as surfaces, and it's these parts that have the highlight. I haven't noticed anything like this in previous releases.