Abstract: A method is disclosed for automatically distinguishing significant from insignificant variants of upper and lower case in a number of input word types by means of a computer. According to the method an input word type is assigned to one of a number of disjoint local groups based on the case, and position, of the letters that make up the input word type. Furthermore, the input word type is assigned to one of a number of disjoint global groups based on which local groups case variants of the input word type are assigned to. Finally the cases of the input word type are normalized in accordance with predetermined rules associated with the global group the input word type is assigned to.