  IceCube has become the first neutrino telescope with a sensitivity below the
TeV neutrino flux predicted from gamma-ray bursts if GRBs are responsible for
the observed cosmic-ray flux above $10^{18}$ eV. Two separate analyses using
the half-complete IceCube detector, one a dedicated search for neutrinos from
$p \gamma$-interactions in the prompt phase of the GRB fireball, and the other
a generic search for any neutrino emission from these sources over a wide range
of energies and emission times, produced no evidence for neutrino emission,
excluding prevailing models at 90% confidence.
