  The search for evidence of beyond Standard Model Higgs bosons is an integral
part of the Higgs boson studies at the LHC. This article reviews recent beyond
Standard Model Higgs boson searches using Run I LHC proton-proton collision
data recorded by the ATLAS detector. In particular, searches for Higgs boson
cascades, double Higgs boson production, scalar particles decaying to
$\gamma\gamma$ pairs, flavor changing neutral currents involving Higgs bosons,
and Higgs bosons decaying to invisible particles are discussed. No significant
deviations from the background expectations are found and corresponding
constraints on physics beyond the Standard Model are obtained.
