  The effects of two-photon exchange corrections, suggested to explain the
difference between measurements of the proton elastic electromagnetic form
factors using the polarization transfer and Rosenbluth techniques, have been
studied in elastic and inelastic scattering data. Such corrections could
introduce epsilon-dependent non-linearities in inelastic Rosenbluth
separations, where epsilon is the virtual photon polarization parameter. It is
concluded that such non-linear effects are consistent with zero for elastic,
resonance, and deep-inelastic scattering for all Q^2 and W^2 values measured.
