So Pong was added because of its undeniable place in the collective psyche of video game players, and its importance to the history of interactive media.

As a lawyer, I can tell you that the trademark example that they use is pretty stupid. Trademarks protect using a signifier (word, logo, etc) for a good or service. Trademarks solve the problem of being able determine the origin of the things you buy so that you can complain to (or praise) the right people when…