we have a keystone residence. i noticed a couple small spots on the roof that looklike mold. is it possible for mold to grow from the underside of the rubber roof?
Yea, if there is a leak, it could happen. Are all your seals and caulking good? I'd have a look around any fixtures in that area or look for small holes in the rubber around there that might be letting water in.
Are you sure it's under the rubber and not on top of it? Maybe a good cleaning will help identify what the problem is, if it's not already clean.