  The projector onto the Minkowski sum of closed convex sets is generally not
equal to the sum of individual projectors. In this work, we provide a complete
answer to the question of characterizing the instances where such an equality
holds. Our results unify and extend the case of linear subspaces and
Zarantonello's results for projectors onto cones. A detailed analysis in the
case of convex combinations is also carried out. We establish the partial sum
property for projectors onto convex cones, and we also present various examples
as well as a detailed analysis in the univariate case.
