I just submitted an article using data from another study that was done together with a colleague. I am (technically) the first author of the first study, though we are equally credited first authors and we did refine the first study’s design together, though it was my idea and I wrote the software that eventually performed the data collection. I did say that the data came from our original study and cited it in the second.
He is upset as I did not ask him for permission to use the data from our joint project (I could probably still tell the journal to add him to the acknowledgements). But, he also wants to be credited as an author, even though he did not contribute to the current study. Does using data from a previous joint project warrant his authorship?