e) Causal link 

In T 61/10 the board pointed out that the existence of a causal link between the limiting feature to be deleted and the new situation arising on appeal was a necessary precondition for justifying an exception to the principle of prohibition of reformatio in peius for reasons of equity. In G 1/99, T 1843/09 and T 1979/11 this condition was fulfilled. However, in the case before the board, the precondition was not fulfilled, so a departure from the principle of prohibition of reformatio in peius based on analogies with the cases cited was not justified.