BrandeX: Maybe, but Activsion publishers here, so it wouldn't be a problem. Take Two doesn't I think.
Activision can be a little strange though. We contacted them through a community manager to see if we can get the source code to Swat 3 and they wouldn't give it to us. Apparently it would have cost them too much money to pay someone to go through the source code to determine if there was 3rd party code in there that they weren't allowed to give out (possibly just an excuse though?)
Maybe something strange like that is going on. Swat 4 used Gamespy for multiplayer but they are completely defunct I think unless someone now still owns the rights.
Perhaps it is just that they are keeping the door open for a Swat 5 if they want and they don't want you to buy Swat 4. Corporations can be strange in their thinking.