The other person’s backward movement and your own contribution should be assessed together.
If the other person moved backwards into a crossing after stopping and the area was visible, that movement warrants close examination. FIS Rule 5 requires a skier entering or restarting after a stop to look uphill and downhill. Your own speed, line and response remain relevant as well.
Under Section 1304 ABGB, your own contribution may reduce compensation in proportion to the contribution to the damage. The evidence must therefore show the sequence and the reaction available to each person.