De minimis exemption for show cause notices narrows procedural obligations, preventing notices in trivial low value customs cases. The amendment inserts a de minimis exemption in section 28(1) of the Customs Act: the proper officer shall not serve a show cause notice where the amount involved is below a specified low-value threshold, thereby removing the obligation to initiate formal show cause proceedings for trivial monetary cases and creating a categorical procedural exception for low-value customs discrepancies.