Rescripts in forma gratiosa are effective from the date they bear; others only from the moment of execution. Rescripts contrary to common law contain a derogatory clause: all things to the contrary notwithstanding.
Rescripts issued with the "forma gratiosa" procedure take effect immediately upon issuance; others are only effective upon execution. Rescripts that deviate from common law typically include a disclaimer, "notwithstanding anything else to the contrary."