  The $ND\Lambda_c$ and $ND^*\Lambda_c$ form factors are evaluated in a full
QCD sum rule calculation. We study the double Borel sum rule for the three
point function of one meson one nucleon and one $\Lambda_c$ current up to order
six in the operator product expansion. The double Borel transform is performed
with respect to the nucleon and $\Lambda_c$ momenta, and the form factor is
evaluated as a function of the momentum $Q^2$ of the heavy meson. These form
factors are relevant to evaluate the charmonium absorption cross section by
hadrons. Our results are compatible with constant form factors in these
vertices.
