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Recently, tentative evidence for an excess of gamma rays at energies around130 GeV has been reported from analyses of data from the Fermi Large AreaTelescope (LAT). The excess is potentially of great interest, as it could beassociated with the pair-annihilation of Galactic dark matter and thesubsequent production of monochromatic or internal bremsstrahlung gamma rays.The 130 GeV excess appears when an optimized selection of the target region ofinterest is employed, a procedure that depends upon the assumed dark matterdensity profile. For the profiles producing an appreciable signal, these targetregions vastly overlap with the region corresponding to the so-called "Fermibubbles". We argue that the tentative evidence for a line feature is likely dueto hard photons in the Fermi bubbles regions, where the gamma-ray spectrumcontains a spectral break in the energy range of interest (100-150 GeV).Although the origin of this broken power-law is unclear, it is probably relatedto standard astrophysical processes and not to dark matter annihilation. Abroken power-law provides as good a fit as a line "excess", even within smallenergy windows, and a significantly better fit for large energy windows.

Gamma-ray Lines in the Fermi Data: is it a Bubble?