(25)Orders placed before a person possesses inside information should not be deemed to be insider dealing. However, where a person comes into possession of inside information, there should be a presumption that any subsequent change relating that information to orders placed before possession of such information, including the cancellation or amendment of an order, or an attempt to cancel or amend an order, constitutes insider dealing. That presumption could, however, be rebutted if the person establishes that he or she did not use the inside information when carrying out the transaction.