The Band's Visit and the attribution of authorship to a book

I have seen The Band’s Visit twice, and finally got around to watching the film. In comparing the two, one of the things that struck me the most was the number of instances in which the book of the musical seemed to directly appropriate dialogue from the film. I don’t have the texts to compare, but I am pretty confident that Itamar Moses’ book includes a number of passages that are verbatim from Eran Kolirin’s film script. Now, I understand that one can expect some of this with adaptations. But this is not an adaptation of a 300 page book. It’s an adaptation of a fairly sparse script. In all other spheres of publication that come to mind – whether literary, academic, or journalistic – the ethical standards would demand that someone who made Kolirin’s contribution receive co-authorship. I’m wondering why that is not the case here.

It's definitely a valid question that becomes more and more applicable as more things become adapted. But there is a long history of passages being taken verbatim from the source material - just look at My Fair Lady vs. Pygmalion. I think it comes down to the rights of adaptation. When they received the rights to adapt the movie, I'm assuming they were giving over their dialogue and story to be used however they saw fit (within limits, perhaps). And that includes taking passages verbatim. But ethically, I agree that in cases like this, it makes sense to credit them as co-authors.



Interestingly, when I was in England for a year, I noticed that a lot of times they would list the source author as the main author, and then list the adaptor separately. For example, the stage adaptation of Kiki's Delivery Service at Southwark Playhouse:

https://southwarkplayhouse.co.uk/archive2017/kikis-delivery-service-2/

Notice that they say "By Eiko Kadono" (the author of the original book) and then the adaptor is listed below. And this was a very common thing I noticed with adaptations in London. The same was true for the recent 1984; "By George Orwell, adapted by Robert Icke and Duncan MacMillan"