invalid - Argument type _____ is not assignable to parameter type ____ Follow

I have an inheritance structure of:

A : B : C

I am supplying a typeof(A) to a method that accepts a parameter of typeof(C).

R# apparently is not respecting the inheritance chain and is only looking at the first ancestor.

R# 6.1 Windows 7 x64 12GB ram VS2010 Ultimate SP1.