Left panel: possible (m₂, r) combinations for companions of β Pictoris, compared to the properties of the known exoplanet β Pic b from Snellen & Brown (2018) and Dupuy et al. (2019) (red symbols). Right panel: mass limits on additional planetary mass companions from its PMa after subtraction of planet b (green curve and shaded green area), and the analysis by Lagrange et al. (2018) (light blue curve). The combined mass limit is shown as a pink curve, and the permitted (m₃, r) range for a second planet is represented as the hatched area.