Heavy top limit and double-logarithmic contributions to Higgs production at m_H² / s << 1

Next-to-next-to-leading order (NNLO) QCD corrections to Higgs boson hadroproduction have recently been calculated in the heavy top-quark limit m_t -> \infty. The m_t -> \infty limit introduces double-logarithmic corrections in ln x, with x = m_H^2 / s. We identify these corrections order by order in alpha_s. As an application, we derive an analytic expression for the dominant x << 1 part of the NNLO coefficient.