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We present spectropolarimetric observations of the Type IIb SN 2001ig in NGC7424; conducted with the ESO VLT FORS1 on 2001 Dec 16, 2002 Jan 3 and 2002 Aug16 or 13, 31 and 256 days post-explosion. These observations are at threedifferent stages of the SN evolution: (1) The hydrogen-rich photospheric phase,(2) the Type II to Type Ib transitional phase and (3) the nebular phase. Ateach of these stages, the observations show remarkably different polarizationproperties as a function of wavelength. We show that the degree of interstellarpolarization is 0.17%. The low intrinsic polarization (~0.2%) at the firstepoch is consistent with an almost spherical (<10% deviation from sphericalsymmetry) hydrogen dominated ejecta. Similar to SN 1987A and to Type IIP SNe, asharp increase in the degree of the polarization (~1%) is observed when theouter hydrogen layer becomes optically thin by day 31; only at this epoch isthe polarization well described by a ``dominant axis.'' The polarization angleof the data shows a rotation through ~40 degrees between the first and secondepochs, indicating that the asymmetries of the first epoch were not directlycoupled with those observed at the second epoch. For the most polarized lines,we observe wavelength-dependent loop structures in addition to the dominantaxis on the Q-U plane. We show that the polarization properties of Type IIb SNeare roughly similar to one another, but with significant differences arisingdue to line blending effects especially with the high velocities observed forSN 2001ig. This suggests that the geometry of SN 2001ig is related to SN 1993Jand that these events may have arisen from a similar binary progenitor system.

Spectropolarimetry of the Type IIb Supernova 2001ig