Eminent domain calls for "Just Compensation" so I'd have to say a blow to. I guess you could argue both.
This isn't an eminent domain case. The Government of South Carolina is basically saying these documents are ours and always have been. They do not belong to this guy, accordinng to the ruling. Therefore, he is not entitled to "just compensation"..........
So if I come across a catch of letters written by Abe Lincoln when he was in the Illinois House of representatives I would have to give them to the State of Illinois rather than be able to sell them or even receive a tax credit for the donation.
This verdict strikes me as being very wrong.