Keyword Types configured for an alphanumeric data type must be assigned a Character Case setting. There are two Character Case options that may be assigned to a Keyword Type: Uppercase Values and Mixed Case Values with an option for Case Sensitive Searching.
Keyword Types configured for Uppercase Values store the Keyword Value in uppercase letters, regardless of how the Keyword Value was entered upon indexing. Keyword Types configured for Mixed Case Values store the Keyword Value upon indexing exactly how it was entered, using both upper and lower case characters.
See your system administrator for details on Keyword Types that may be configured for Mixed Case Values.