Books in the 1700s and 1800s are no longer under copyright, they are now in the public domain. Anybody can sell them for whatever the market will bear. Since they are not longer under copyright, there is no longer a copyright holder whose rights they are infringing and thus nobody that can charge them for violating copyright law.
The question with Highsmith is whether she still holds the copyright or whether she put the pictures in the public domain. Answering this could be very interesting.
The other angle that I would expect to see come up is whether Getty can sue (or threaten to sue) over pictures that they clearly do not hold the copyright to. That seems to be a clear violation of racketeering laws. https://en.wikipedia.org/wiki/Racketeering
* https://en.wikipedia.org/wiki/Public_domain "Works in the public domain are those whose exclusive intellectual property rights have expired, have been forfeited, or are inapplicable."
The question with Highsmith is whether she still holds the copyright or whether she put the pictures in the public domain. Answering this could be very interesting.
The other angle that I would expect to see come up is whether Getty can sue (or threaten to sue) over pictures that they clearly do not hold the copyright to. That seems to be a clear violation of racketeering laws. https://en.wikipedia.org/wiki/Racketeering
Ref:
* http://www.copyright.gov/help/faq/faq-duration.html#duration
* https://en.wikipedia.org/wiki/Public_domain "Works in the public domain are those whose exclusive intellectual property rights have expired, have been forfeited, or are inapplicable."