GNU has a helpful chart where they clearly show that there is a sliver of "nonfree open source" licenses that are available [0].
> The term “open source” software is used by some people to mean more or less the same category as free software. It is not exactly the same class of software: they accept some licenses that we consider too restrictive, and there are free software licenses they have not accepted. However, the differences in extension of the category are small: we know of only a few cases of source code that is open source but not free.
I was able to find one example, the NASA Open Source Agreement, which is accepted by the OSI [1] but rejected by the FSF [2]:
> The NASA Open Source Agreement, version 1.3, is not a free software license because it includes a provision requiring changes to be your “original creation”. Free software development depends on combining code from third parties, and the NASA license doesn't permit this.
Guarantee that all "nonfree open source" is different readings. Take the NASA case. If youu read it as strictly as Stallman does then it violates the OSD also. The people at OSI at the time it was submitted read it more like a lawyer and decided it was compliant. Possibly today's OSI would disagree. Possibly tomorrow's FSF would agree. It's not a difference between free software and open source but a difference between how two sets of humans interpreted the text of the license.
Eh, OSD 3 just says that derived works must be possible, it doesn't say that you must be able to incorporate third party source code into the derived work. Meanwhile the FSF's definition explicitly calls out this freedom as an essential component of Freedom 1:
> One important way to modify a program is by merging in available free subroutines and modules. If the program's license says that you cannot merge in a suitably licensed existing module—for instance, if it requires you to be the copyright holder of any code you add—then the license is too restrictive to qualify as free.
