  The Einstein equivalence principle is based on the equality of gravitational
mass and inertial mass, which has led to the universality of a free-fall
concept. The principle has been extremely well tested so far and has been
tested with a great precision. However, all these tests and the corresponding
arguments are based on a classical setup where the notion of position and
velocity of the mass is associated with a classical value as opposed to the
quantum entities. Here, we will provide a simple protocol based on creating
large spatial superposition states in a laboratory to test the fully quantum
regime of the equivalence principle where both matter and gravity are treated
at par as a quantum entity. We will argue that such a quantum protocol is
unique with regard to testing especially the generalization of the weak
equivalence principle via witnessing quantum entanglement.
