Common proper motion plot for the planet HD 95086 b. The position of the planet at the first epoch is represented by the black cross, the expected position at the second epoch, if background, by the red hollow cross, and the measured position at the second epoch by the plain red cross (errorbars are included but due to the high S/N and the scale, they are not visible). The two red crosses are widely separated, displaying a motion non-compatible with a background source. Additionally, the motion of the planet is compatible with an orbital motion around the star.