Epoch and resampled BP and RP spectra of the first and third components of the quadruple lens system GraL J065904.1+162909 (Delchambre et al. 2019; Stern et al. 2021), corresponding to the GravLens multiplet DR3Gaia065903.826+162907.83. Points are the epoch BP/RP spectra of each of the components (blue for BP, red for RP) while solid lines are the resampled BP/RP spectra, as described in Sect. 5.3. We also provide the additional parameters derived during the resampling phase: mean resampling chi-square $\left({\chi }_{\text{XP}}^2\right)$, integrated flux (F_XP) and signal-to-noise ratio (S/N_XP) where XP stands for BP or RP. Both component spectra show strong Lyα and CIV emission lines that allow us to unambiguously identify this multiplet as a lensed QSO.