  The so called Inomata-McKinley spinors are a particular solution of the
non-linear Heisenberg equation. In fact, free linear massive (or mass-less)
Dirac fields are well known to be represented as a combination of
Inomata-McKinley spinors. More recently, a subclass of Inomata-McKinley spinors
were used to describe neutrino physics. In this paper we show that Dirac
spinors undergoing this restricted Inomata-McKinley decomposition are
necessarily of the first type, according to the Lounesto classification.
Moreover, we also show that this type one subclass spinors has not an exotic
counterpart. Finally, implications of these results are discussed, regarding
the understanding of the spacetime background topology.
