[D] Who should get co-authorship? Need advice for ICML

Around April 2025, I started working on a paper for ICLR. The plan was to collaborate (equally) with one of my PhD supervisor’s students, but as time went on, I took on most of the responsibility and ended up writing the entire paper + coding all the main results and ablations. The other student ran some baselines, but the results had mistakes. So I had to re-implement and correct the baselines. In the final version, everything including writing, code, plots, figures, etc., was my own work.

While I was busy with this work, the other student was working on another paper using my code (without including me as a co-author). To be clear: they took my code as a starting point and implemented something on top. I think this was really unfair. Given that we were supposed to collaborate equally, they decided instead to do the minimum to be part of the work while working to get a second paper. My PhD supervisor wasn’t involved in most of this process–they usually schedule meetings ~2 weeks before conference deadlines to see what I have ready to submit. I also think this is unfair: I spend hundreds of hours working on a paper, and they get co-authorship by reviewing the abstract.

Who should get co-authorship here?

From September, I started working on a paper for ICML. I spent so much time on this paper, not taking Christmas holiday, etc. I was expecting the same request for a meeting two weeks before the deadline, but this time, one day before the Abstract deadline, my supervisor asks me “What are we submitting to ICML?” Keep in mind, we haven’t spoken since the ICLR deadline and they have no idea what I have been working on. I wasn’t sure what to do, but I ended up adding them as a co-author. I really regret this decision.

Should they get co-authorship just for being a supervisor? If there was an option to remove them, for example, by emailing PCs, should I do it?