Relative astrometric position of the proposed companion in the first and the last observing epoch. The solid black line represents the expected course of the companion if it were a stationary background object. The black square at the end of the line represents the expected position at the epoch of the last observation in this case. The minor difference between the observed and expected positions is consistent at ~1.5cr with measurement errors or could be due to a non-zero intrinsic motion of the background source.