The case that started this was Guttenberg, and that was very blatant plagiarism on a large scale in his PhD thesis. That one was certainly intentional. The most recent one was the Green chancellor candidate in the current election, Baerbock. In my opinion her case isn't actually plagiarism as it was mostly about collections of facts in her book. So some very short passages were taking from other sources, but these were things like the list of countries that joined the EU.
What I hate about these cases is that it is pretty much impossible to determine how serious the cases are from the news coverage. You have to actually look into the alleged plagiarised sections yourself. The first case was a real and very serious case that rightfully stopped Guttenberg's political career at that point. But since then this has also become a political tool, and some of the people doing this have clear political motives for it.