Inca, eh? :P
Well, I am the ESA expert on this site (as I have a LOT of experience with them by now). As many people say, it doesn't matter what happens to the different companies, but rather what happens to the copyright for each individual game. However, what is most common is for a big company to buy up
all the rights from a company (a buy-out).
Thus it is more common to find 1 or 2 games from a bought out company, in where the copyright lies with the actual game-programmer(s). And in those rare cases, the programmer(s) more than often releases the games as freeware for all to enjoy.
As to directly answer the question about Coktel and Inca I & II:
Both Inca games were made by Sierra On-Line and Coktel Vision, and the copyrights for
both Sierra On-Line and Coktel Vision are today in the hands of Vivendi Universal - which pays ESA a lot of money each year to protect "their" copyrights.
So both Inca I and Inca II are protected by ESA, however... Inca II is still available for sale
here.
:Tom: