  We studied the polarization properties of Cygnus X-1 in both hard and soft
spectral states with Imaging X-ray Polarimetry Explorer (IXPE) observations.
The polarization degree is $\sim4$%, and $\sim 2.6-2.8$% in the hard and soft
states, respectively. The polarization angle is observed along the jet axis and
remains the same in both states. Energy-dependent analysis revealed an
increasing polarization with the energy. The observed polarization rules out
the lamp-post corona and prefers a conical corona if the coronal geometry
remains the same in the hard and soft states. The disk is not detected in the
hard state but is found in the soft state in the IXPE spectra. The spectral
analysis revealed that the disk emission contributes $\sim 20$% of the total
emission in the soft state. The scattering of the seed photons inside the
corona is likely to reduce the polarization. This could explain the different
polarization in different spectral states. Additionally, if the disk
polarization is perpendicular to that of the corona, it could also reduce the
polarization in the soft state.
