The way that big software companies used to make software was hiring all the smart people, locking them in a room, and sliding pizza under the door, until they had written whatever needed writing. And then selling tickets to get into the room.
Sun is one of many US companies that file software patents regularly, the reason we file software patents regularly is the same reason that Americans buy guns. Americans buy guns, because Americans buy guns. American corporations file software patents because American corporations file software patents."