Many fraudulent checks are visibly phony. By paying close attention to a check's appearance, you can often detect a possible bad check before accepting it as payment. When you see one or more of the following telltale signs, you may be looking at a phony check. Protect yourself against possible losses by requiring management approval of the check or asking for an alternative form of payment.
No perforation on check edges.
Apparently altered writing or erasures.
Water spots or alterations of check's color or graphic background.