How to distinguish DB2 client without server

One of our customer is interested to distinguish standalone "DB2 client" not part of a server installation. Would any one has any suggestions how this can be achieved?

Problem is that DB2 server will always have DB2 client bundled. Moreover, DB2 client will either install a "default DB2 instance" for you, or require pointing DB2 client to another running instances. It is a mess to figure out which one of the client can be removed, and which one is which. What is best way to tell them apart?

Suggestions welcome.

Thanks.
-Allex