By european law it is no problem at all to lend the original to any friend. You bought it, so you can give it away. Important is only that no one makes an illegal copy which means only one person is allowed to play with your game at a time. Exception are some multiplayergames which allow spawned versions or make sharing possible but the game usually must stay with one owner. You are so far (the law is changing this month) allowed to make ONE backup copy of your software. But only for yourself.
