[Boost-users] derivative work

Hi there, just a short question about the meaning of "derivative work" in the Boost software license (and the associated requirement to list the Copyright and license terms in such work). My understanding of the term "derivative work" is that it applies to modifications of the original code only, not to software _using_ the code. I.e., if I were to modify the code in shared_ptr.hpp, then of course I would have to include the original Copyright notices and license terms. Whereas, if I use shared_ptr in my software, I do not need to list the original Copyright notices and license terms. Plus, the Copyright of my own cose is solely with me. Is this interpretation correct ? Best Regards and thanks for your help, Ruediger Berlich