In this talk, we present a uniqueness result for solutions to the Gross-Pitaevskii hierarchy on the three-dimensional torus, under the assumption of an a priori spacetime bound. We show that this a priori bound is satisfied for factorized solutions coming from a solution of the nonlinear Schrodinger equation, thus obtaining a periodic analogue of the uniqueness result on R3 previously proved by Klainerman and Machedon. This is joint work with Gigliola Staffilani.