  Massless superparticle model is considered on the OSp(4|6)/(SO(1,3) x U(3))
supercoset manifold and in the AdS_4 x CP^3 superspace. In the former case
integrability of the equations of motion is rather obvious, while for the AdS_4
x CP^3 superparticle we prove integrability in the partial kappa-symmetry gauge
for which 4 anticommuting coordinates related to the broken conformal
supersymmetry are set to zero. This allows us to propose expression for the Lax
pair that may encode complete equations of motion for the AdS_4 x CP^3
superparticle.
