SHEET NUMBERING PROCESS AND SHEET-PROCESSING MACHINE FOR CARRYING OUT THE SAME

There is described a sheet numbering process involving feeding of individual sheets (S) in succession, which individual sheets (S) each carry a plurality of imprints (P) that are arranged in a matrix of rows and columns, and providing unique serial numbers to multiple ones of the plurality of imprints (P) carried by the individual sheets (S). The sheet numbering process comprises numbering of at least some of the individual sheets (S), wherein numbering of the individual sheets (S) is selectively commutable between a first numbering scheme (N1) and at least a second numbering scheme (N2; N2′; N*), different from the first numbering scheme (N1), without interruption of the numbering process. The first numbering scheme (N1) involves providing all imprints (P) of a first subset (S0) of individual sheets (S) with a unique serial number (SN1) of the first numbering scheme (N1). The second numbering scheme (N2; N2′; N*) involves providing all or part of the imprints (P) of a second subset (S′; S*) of individual sheets (S) with a unique serial number (SN2; SN2′; SN*) of the second numbering scheme (N2; N2′; N*). The first subset (S0) of individual sheets (S) and the second subset (S′; S*) of individual sheets are sorted after numbering in dependence of the numbering scheme (N1; N2; N2′; N*). Also described is a sheet-processing machine for carrying out the aforementioned sheet numbering process.