A simple or a compound type value might appear multiple times in a SOAP message leading to data duplication. However, SOAP allows values to be referenced multiple times inside a document so that redundancy can be eliminated. Multi-referencing values are best used when large amounts of data need to be transacted through a SOAP message.

The code example demonstrates an instance where data is redundant. The student structure contains the student's registration number, name, and address. The address is also a structure. As a result, it appears that two students live at the same address.