Since 1996, the CAT experiment, operating at the THEMIS site (French Pyrenees), has been collecting Very High Energy (VHE) gamma-ray data from the Crab. The temporal analysis of photon arrival times folded with the pulsar parameters did not reveal any significant pulsation. The upper limit of a steady pulsed flux over the 102.7 hours of observation is 1.5 10^-12 cm^-2.s^-1, 3.0 10^-13 cm^-2.s^-1 and 5.4 10^-14 cm^-2.s^-1 above 250 GeV, 1 TeV and 5 TeV, respectively. These results put stringent constraints on the models of high energy pulsar electrodynamics.
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