Local Distinguishability of Any Three Quantum States
  We prove that any three linearly independent pure quantum states can always be locally distinguished with nonzero probability regardless of their dimension, entanglement, or multipartite structure. Almost always, all three states can be unambiguously identified. The only exceptional case, where one state is locally knowable but the other two are not, is found among multi-qubit states. 
Somshubhro Bandyopadhyay and Jonathan Walgate