Is it legitimate to present self-developed, but commercial, software within my dissertation? The situation goes like this: Within my dissertation (doctoral degree) I present a software library which I wrote by myself for a company I work for. Thus, the software is commercial and the rights are owned by the company. The company is fine that I present the software in the dissertation. The software is presented in the dissertation by an own chapter and used for experimental evaluations. However, is it legitimate to present such a software as part of the dissertation from an academia point of view?
It depends on your actual area. In general, I believe that it is acceptable (I'm in Electrical engineering). However, you need to justify your scientific contribution. How is the work you did in this software a contribution to your thesis? 

Also, as a thesis examiner, I would expect a detailed description of the algorithms / methods developed for this software to be able to assess your contributions. Are you willing to do so? Does the company you work for allow you to disclose this information?