Merger doctrine

U.S. copyright law
Under the merger doctrine, “even expression is not protected in those instances where there is only one or so few ways of expressing an idea that protection of the expression would effectively accord protection to the idea itself.” Courts must exercise “considerable care” in applying the doctrine, since “if the merger doctrine is applied too readily, arguably available alternative forms of expression will be precluded; if applied too sparingly, protection will be accorded to ideas.”