H → ggg(gqq) at two loops in the large-Mt limit

We present a calculation of the two-loop helicity amplitudes for the processes H → ggg and H → gqq in the large-Mt limit. In this limit the calculation can be performed in terms of one-loop diagrams containing an effective Hgg operator. These amplitudes are required for the next-to-leading order (NLO) corrections to the Higgs transverse momentum distribution and the next-to-next-to-leading order (NNLO) corrections to the Higgs production cross section via the gluon fusion mechanism.