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Preliminary results of BATSE occultation measurements of the nearby Seyfert galaxy NGC 4151 will be presented. This AGN is variable on time scales of a few days, but long-term daily monitoring has never been possible in X-rays or gamma-rays prior to BATSE. Of prime interest are spectral studies to determine the nature and duty-cycle of the recently discovered break or exponential cutoff above ~80 keV. Correlations between flux intensity and spectral shape can also be investigated. The standard occultation analysis allows detection of NGC 4151 on few-day time scales and spectral measurements on week time scales.