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Variability of the spin period of the white dwarf in the V405 Aur (RXJ0558.0+5353) system using our observations and previously published maximatimings is analyzed. As the phase light curve contains two nearly equalphotometric waves, one maximum was set as a "primary" one. The ephemeris forthe maxima of the "spin variability" (due to rotation of the magnetized whitedwarf) for recent seasons 2010-2012 is Tmax = HJD2455882.470614(25)+0.00631314602(46)E. This corresponds to a significantnegative trend at the "O-C" diagram. Due to significant gaps in theobservational data and statistical error of timings, there may be somesuggestions on the spin period variability - a fast period "jump" in 2007y;secular period variations; a cubic ephemeris (which may be interpreted by aprecession of the magnetic white dwarf at a time-scale of decades) or aperiodic change with a period of 6.2 years and semi-amplitude of 17.2\pm1.8sec. For the present observations, more reliable are two latter models. Todistinguish between them, a continuation of monitoring is needed. The periodicvariations may be interpreted by a light time effect caused by a third body ofmass (M3 > 0.09M\odot), which corresponds to a low-mass star, but not to anextra-solar planet. In this case, the system belongs to a rare class ofcataclysmic variables with a third body.

Is There a Third Component in the Intermediate Polar V405 Aur?