Incorrect rewrite of not disjunctive criteria

The rewrite of a condition such as "not((a or b) AND c)" with a,b,c predicates where c a is predicate that is negatable, such as col1 = 1. The result should have the negated form of col1 <> 1, but instead has col1 = 1. This is because the col1 = 1 predicate is repeated in the result, but not cloned and the rewriter modifies the same instance.