  We summarise predictions for top anti-top bottom anti-bottom (tTbB)
production at the LHC in next-to-leading order QCD. The precise description of
this background process is a prerequisite to observe associated top anti-top
Higgs production in the H -> bottom anti-bottom decay channel. The one-loop
amplitudes are computed using Feynman diagrams and numerical tensor reduction.
This approach provides very high numerical stability and CPU efficiency. We
find that the scale choice adopted in ATLAS simulations underestimates the tTbB
background by a factor two and introduce a new dynamical scale that stabilises
the perturbative predictions. In the regime of highly boosted Higgs bosons,
which offers better perspectives to observe the tTH(H-> bB) signal, the
corrections induce significant distortions in the kinematic distributions.
