The whole point of copyright law is to increase the production of books, music, and other media so that there is more available for people to enjoy. If copyright is too weak, then there is little incentive to make an expensive move or produce an expensive satellite image because there will be no way to recoup the expenses by selling copies. If copyright is too strong, that will stifle creativity and freedom of speech because all expression depends on prior art that we copy from other. I cannot write this sentence without language that someone else created and a computer interface that someone invented (keyboard & mouse). If people could claim copyright some of these particular phrases, it would stifle my ability to express myself and if someone patented the computer keyboard, then they could charge extra fees for every computer and that would make computing excessively expensive and reduce computer use rather than increasing it.
In the realm of book publishing, a new paper analyzes whether book copyright is too weak or too strong. They find that copyright seems to be too strong and should be shorter because copy-written books are rarely available at all after a short time and then disappear. Once copyright expires, they tend to reappear on the market again. Here is a selection that Freakonomics snipped:
Influential copyright lobbyists presently circle the globe advocating ever longer terms of copyright protection based on this under-exploitation hypothesis–that bad things happen when a copyright expires, the work loses its owner, and it falls into the public domain. By analyzing present distribution patterns of books and music, this article tests the assumption that works will be under-exploited unless they are owned and therefore questions the validity of arguments in favor of copyright term extension…
[Our research] collects data from a random selection of new editions for sale on http://www.amazon.com (“Amazon”) and music found on new movie DVD’s for sale on Amazon. By examining what is for sale “on the shelf,” the analysis of this data reveals a striking finding that directly contradicts the under-exploitation theory of copyright: Copyright correlates significantly with the disappearance of works rather than with their availability. Shortly after works are created and proprietized, they tend to disappear from public view only to reappear in significantly increased numbers when they fall into the public domain and lose their owners. For example, more than twice as many new books originally published in the 1890’s are for sale by Amazon than books from the 1950’s, despite the fact that many fewer books were published in the 1890’s.
It turns out that books from the 19th century are much easier to find than books from the 20th century because more recent books are copyrighted! Freakonomics comments that:
Heald’s findings speak to a disconnect between politics and economics in copyright law. There are clearly some 20th century works that are quite old (think Mickey Mouse), that have enduring commercial value, and for which their owners (think Disney) carefully study how best to exploit them in a 21st century market. But for the typical older work, no one is paying any attention because demand for the work in the market is low. Books from the 1940s, for instance, are very often out of print and while they may be available in some libraries and in the occasional well-stocked used book store; you or I would have a very hard time tracking one down for purchase.
An economically-rational copyright policy would balance these sorts of works against the very rare works that maintain high demand over long periods of time. Instead, our copyright policy in Congress is driven by the interests of copyright owners such as Disney, for whom longer terms are better and the best copyright term (for their own works, at least) is infinite. At their behest, copyright terms have grown longer and longer—now life of the author plus 70 years. Yet, as Heald suggests, availability to consumers has diminished.