Assertion list for term "difficult to enforce".

Results from Ascent++: 5
prohibition ReceivesActiondifficult to enforce 0.31
ban ReceivesActiondifficult to enforce 0.31
patent ReceivesActiondifficult to enforce 0.30
covenant ReceivesActiondifficult to enforce 0.22
copyright ReceivesActiondifficult to enforce 0.21