While learning in Yeshiva, we focused also on clarifying our Mesorah. We are medakdek to know the Chachamim that are discussed in each sefer. One Sefer that helps us in clarifying who the Chachamim we are quoting are, is the Chida's Shem Hagedolim.
So is there a rule of thumb to follow, to automatically know that ibn isnot his father's name. It makes nafka minas for when someone quotes his father. I started checking, and in my little research, I don't think I've found yet one famous Mechaber Sefer that the ibn Ploni was in line with his father's actual name.
Several examples: Both Rabbenu Bachya's, R' Yosef ibn Migash, R' Yehuda ibn Tibbon, Ibn Ezra.
Thank you for your help