V8i Compatibility

My company is going through a revamp of our guideline on how we recieve drawings and models from our vendors.  As of right now we are using V8i SS3.  I have been searching all over to find out how far back someone can create a dgn that will work seemlessly with SS3.  Right now our guide say 95 but I am certain that won't work.  Does anyone know?  Thanks in advance.