a procedure developed in 1962 as a way of cleaning up a case in order to run Routine 3D Criss Cross. Thus Prepchecking for Preparatory checking. The target of a prepcheck question was a chain of withholds. The purpose of Prepchecking was to set up a pc's rudiments so they would stay in during further clearing of the bank. Since September 1963 the term Prepchecking has been used to apply to a different procedure developed at that time. —ProTRs Transcript Glossary. Final approval 29/10/89