Top: RM anomaly induced by GJ 436 b in the RV residuals measured in Visits 1 (orange) and 2 (blue). Black dots represent a binning of the RV data with a bin size of 2.5 over the combined transits. The red line shows the classical fit to the anomaly, with associated uncertainty depicted by the gray area. Vertical dashed lines indicate the first and fourth transit contacts. Bottom: RV residuals, which display an overall dispersion of 65 cm s⁻¹.