  The symmetry group of the de Sitter spacetime, accommodates fields of various
masses and spin among its unitary irreducible representations. These unitary
representations are labeled by the spin and the weight contribution to the
scaling dimension and depending on the mass and spin of the field the weight
may take either purely real or purely imaginary values. In this work, we
construct the late time boundary operators for a massive scalar field
propagating in de Sitter spacetime, in arbitrary dimensions. We show that
contrary to the case of Anti de Sitter, purely imaginary weights also
correspond to unitary operators, as well as the ones with real weight, and
identify the corresponding unitary representations. We demonstrate that these
operators correspond to the late time boundary operators and elucidate that all
of them have positive definite norm.
