I'm curious if you've reached out to the big players in the textbook oligopoly before this?
As to their lawsuit, good luck. I never understood why my books were so expensive (early 2000s). Of course if you're using the chapter titles of their texts as someone mentioned, I'm not an expert on copyright law, but it just feels wrong.
The same way you can review a movie in the local paper or even a TV station can do a movie review and use short clips.
So while it would be possible to discuss and give examples of how a textbook presented information (as a critique of that textbook) you can't copy it (apparently as being claimed) in the way boundless is doing.
As the OP pointed out we will know more when they file their response.
The publishers claim doesn't hang on you rewriting their content. They say you've "[copied] the precise selection, structure, organization, and depth of coverage in [their] textbooks and mapped in substitute text, right down to duplicating [the publishers] pagination", and that you "[took] hundreds of topics, sub-topics, and sub-sub-topics that comprise [the publishers] textbooks and copied them into Boundless texts, even presenting them in the same order, and keying their placement to [publishers] actual pagination"; also, that you "[copied] or [paraphrased] with respect to the substance of hundreds of photographs, illustrations, captions, and other original aspects of [publishers] textbooks".
Look, most of us on HN have read many college textbooks. I think we all recognize that way more goes into a textbook than just the prose.
I'm not judging you, just message-board-nerding your comment here. This is pretty common in threads about legal actions. "We didn't do XXYM", where /\AXX..\Z/ is what's been alleged.
Allowing Smokey the Thermodynamics Bear was a super bad idea, by the way.
1. In order to profit from references to the source text's section+page numbers, they took care to edit, reorder, and adjust layout so that the identity mapping suffices. This makes me wonder: what compromises did they have to make to achieve this? Why didn't they just provide an easy to use lookup index?
2. They copied the texts, thinking that paraphrasing would protect them. (or laxly supervised contractors/employees who resorted to copying)
As to their lawsuit, good luck. I never understood why my books were so expensive (early 2000s). Of course if you're using the chapter titles of their texts as someone mentioned, I'm not an expert on copyright law, but it just feels wrong.