The ESRI Maplex Label Engine was designed to place labels on printed map sheets and is optimized to produce the best quality of placement on a map extent that does not exceed the size of an A0 sheet (841 mm X 1,189 mm). To place labels for a larger extent, it is necessary to divide the total extent into tiles and place the labels for each tile separately. As a guideline, verify that the tile size does not exceed the size of an A0 (or ANSI E
size) sheet in page units. For map extents larger than A0, the placement quality may degrade and, in some cases, labels may not be produced by the placement engine.