Mass vs. C/O ratio for directly imaged companions, building on the work of Hoch et al. (2023). The magenta points represent the original sample of directly imaged planets, while the purple points indicate the three new measurements provided by this work. Recently published values have been added in black, including updated measurements for HR 8799 bcde (Nasedkin et al. 2024), AF Lep b (Balmer et al. 2025), β Pic b (Ravet et al., in prep.), YSES 1 bc (Zhang et al. 2024), and the Keck/KPIC sample published by Xuan et al. (2024). The dashed line and gray shaded area represent the solar C/O ratio with uncertainties (0.59 ± 0.1) as provided by Asplund et al. (2021).