One function of the fourth element of the fair use inquiry is to determine whether the copyright holder will be harmed because the infringing book acts as a market substitute for either the original or a derivative work. While the book cannot serve as a market substitute for the richly entertaining television shows and movies, it can interfere with Paramount's market for derivative works. Paramount licenses a number of guide books that appear to be derivative works, such as The Star Trek Encyclopedia and Star Trek Chronology — The History of the Future. The Joy of Trek itself proclaims that, "[t]his book provides you with more than enough information ... [y]ou do not need to consult encyclopedias or compendiums." This statement speaks for itself.
Defendants claim that their book differs from any work presently licensed by Paramount. This makes no difference. A person interested in learning about the fictional history of Star Trek now must purchase a product licensed by Paramount. This book serves as a potential substitute. Citing the adage, "don't listen to what we say, watch what we do," Defendants also argue that Plaintiff's lack of legal action against other allegedly infringing indicates that The Joy of Trek will not damage a potential market. This argument is without merit. It is possible that Paramount believed that the other books did not infringe on the Star Trek Properties. It is also possible that Paramount simply has had a change in corporate policy, determining that the market is now ripe for this type of derivative product. Regardless, the lack of earlier litigation against other similar works is simply irrelevant. A self-avowed substitute for other Paramount licensed products adversely impacts the market for derivative works.
