I am in an oddball situation where I have amassed a number credits beyond a masters at University in the US. I am currently working in a research setting, but I am aware that without the PhD by career ceiling is somewhat low. I do not want to leave and go back full time because I like my job and I want to stay in industry anyway.
Hypothetically, assuming no IP issues, is it possible to write a thesis on a private work related topic? I would be returning to the same school that gave me the masters degree and I would self fund, but I am curious to know if I would face a lot of friction if I asked. The research topic is not a core strength for the department but I just need to affiliation etc... I work with all PhDs from respected institution, who would be pseudo advisers. Getting a PhD on my day to day work would be advantageous since I already have a sound background and I know my degree would be marketable.