Consider this: In a clean room, the couch never gets dirty.

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No Xbox 360 or trip to Disney World for this kid, who has to clean up his own room but gets no allowance from his parents.

FORBES: Magazine Article

He and his brother clean every inch of this hellish place, and the reader is forced to share the experience, room by room.

NEWYORKER: Total Recall

In this case, the European Union has made its position clear - on this side of the pond APIs are not copyrightable, and developers may produce a so-called "clean room" implementation of an API without running foul of copyright law.

BBC: Viewpoint: Google and Oracle's Java clash must be resolved