  It is known that, in an asymptotically flat spacetime, null infinity cannot
act as an initial-value surface for massive real scalar fields. Exploiting
tools proper of harmonic analysis on hyperboloids and global norm estimates for
the wave operator, we show that it is possible to circumvent such obstruction
at least in Minkowski spacetime. Hence we project norm-finite solutions of the
Klein-Gordon equation of motion in data on null infinity and, eventually, we
interpret them in terms of boundary free field theory.
