No response to after PhD interview, Germany I had a face-to-face interview in a research institute for a PhD in BW, Germany (Don't want to mention city and institute for confidentiality) on the 16th of September 2019. The interview itself went quiet well, but I told them I could start from December onwards. I wrote to the Professor in November that I am available and the Prof. just responded "thanks for your patience". I wrote them (the Prof. and their secretariat) again a couple of weeks ago for an update on the application status and whether if I am still a candidate for the position (P.S. In very smart and polite way). I haven't received any response yet. Should I consider this a rejection? It has been almost 3 months since the interview and almost one year since my MSc graduation.
I was a candidate in an application process at a university in Bavaria a few years ago. After the interview, more than a year went by without me hearing anything from them. I wrote them a letter formally withdrawing my candidacy, since in this time I had already found a good job elsewhere.

I later learned through the grapevine that someone else was ranked first in the process, but negotiations between them and the university took forever. Once negotiations were finished, the official job offer still had to wait until the faculty council approved the offer, and this council met only every second month. Thereafter, the offer had to be sent out, and the offer had to be accepted. All this bureaucracy made things take forever.

"Thanks for your patience" tells me that you are still on the reserve list as a suitable candidate; you're not (yet) rejected. However, it's quite likely that someone else is the preferred candidate. Negotiations with this candidate are ongoing, and unless they don't manage to work it out, the job will not be yours. I would start looking elsewhere.