  We present the polynomiality sum rules for all leading-twist quark and gluon
generalized parton distributions (GPDs) of spin-1 targets such as the deuteron
nucleus. The sum rules connect the Mellin moments of these GPDs to polynomials
in skewness parameter $\xi$, which contain generalized form factors (GFFs) as
their coefficients. The decompositions of local currents in terms of
generalized form factors for spin-1 targets are obtained as a byproduct of this
derivation.
