Why is Brill selling chapters of my book for $30? I just found that PDFs of chapters of my book (Semitic Noun Patterns, Harvard Semitic Studies 52, 2003) are  being sold for $30 each by Brill, a giant academic publisher, who did not publish the book.

The whole thing can be bought on paper for $32 (e.g. at Amazon), or, blessedly, downloaded for free from Library Genesis.

What is going on? The Eisenbrauns family business that originally published the book was bought out by Penn State University Press -- not Brill -- while the President and Fellows of Harvard University own the copyright -- so how can Brill pull off this scam?  

If you know about the presumed deal allowing Brill to do this, I would appreciate learning about it.
Brill Announces Collaboration with the Harvard Semitic Museum on Three Book Series
(September 29, 2017).

This is most likely a press release from Brill, so I wouldn't give it 100% credibility just because it looks official. That said, I don't see why your priors are so much against it either. Recently, the Mathematical Association of America handed its journals (including its de-facto flagship, the American Mathematical Monthly) over to Taylor&amp;Francis. If nothing else, it likely has taken a load off their backs, since they now no longer have to keep track of subscriptions and access.

EDIT: See the "Buy now at Brill" link at the HSS website? That should confirm it.

EDIT2: None of this should be read as a defense of giants swallowing academic (university- or society-based) micropublishers. It's just something that works in the current environment, for reasons that themselves would probably make a good question. I wouldn't be surprised if money is moving around under the table here, but at the same time I expect at least some of it being due to the increasing difficulties of handling subscriptions, payments and access controls when writing for a worldwide audience (GDPR and US export controls are but two things that come to my mind). I think we're going to end up with a bipolar publishing scene, with commercial giants on one side and OA on the other.