Does anyone know if there is an official repository that lists games officially declared public domain by their respecitive rights holders and lists official shareware/freeware - ie titles that companies have released to the public for play/swap but still retain commercial rights to?

I'm trying to get a better handle on what's what in this area and though I've found susinct definitions of the copyright law in the abstract and isolated examples of games where right's holders have explicitly granted public domain status, I don't find a central authority or repository that lists the official status of most games.

To date, a fair number of rights holders in the out-of-print realm have officially gone on record in this regard and such a resource might be helpfull in tempering the extremes in the debate over 'abandonware', or at least give it some kind of objective backdrop. 

hmmm... lots of looks, no replies must = no..

I guess it's nearly impossible to keep track of all game rights

I wouldn't be surprised that some of the larger corporations don't know exactly which rights they hold exactly, especially with companies like EA that have aquired lots of other smaller ones