We study necessary conditions for compactness of the weighted ∂-Neumann operator on the space L 2 (C n , e −ϕ ) for a plurisubharmonic function ϕ. Under the assumption that the corresponding weighted Bergman space of entire functions has infinite dimension, a weaker result is obtained by simpler methods. Moreover, we investigate (non-) compactness of the ∂-Neumann operator for decoupled weights, which are of the form ϕ(z) = ϕ1(z1) + · · · + ϕn(zn). More can be said if every ∆ϕj defines a nontrivial doubling measure.2010 Mathematics Subject Classification. Primary 32W05; Secondary 30H20, 35N15, 35P10.