A novel algorithm capable of localizing Polarization-Dependent Loss (PDL) and directly estimating its value in a multi-span optical transmission link using only Rx-side Digital Signal Processing (DSP) is proposed. The algorithm employs a Linear Least Squares-based power profile estimation method and it succeeds in localizing multiple PDL sources along the link. Its performance is evaluated across diverse power levels, including SNR-maximizing ones, resulting in consistently comparable results.