We derive limits on the intrinsic charm (IC) content of the proton,
considering various theoretical models for IC and using as a basis
the experimental upper limit on the prompt neutrino flux reported
by the IceCube collaboration in their analysis of throughgoing muon tracks
from the Northern Hemisphere.
Our upper limit on the IC follows from the condition that the
total prompt neutrino flux comprising the contributions from both the
perturbative QCD heavy-flavour production and the process of freeing and hadronizing IC saturates the IceCube limit.