The polarization of Pc 3 (22-100 mHz) magnetic pulsations measured by the ATS 6 fluxgate magnetometer at synchronous orbit has been examined by using dynamic autospectral analysis. In contrast to the result obtained by Arthur et al. [1977> using the same data set, we find very few cases of radially polarized Pc 3 pulsations. We argue that satellite noise in the radial component, which depends on frequency f as 0.015/f (nT2/Hz), is responsible for this disagreement. In the presence of this type of noise, diagonalization of the spectral matrix can produce an erroneous major axis of polarization. Most Pc 3 pulsations classified as radially polarized by Arthur et al. appear to be a consequence of small-amplitude azimuthal pulsations contaminated by satellite noise.