Longer copyright terms harm knowledge production and scientific discovery.

3.2 The prevailing trend in most simulations was that increasing the copyright term resulted decreased knowledge production. The declining trend is intuitive, because under shorter copyright protection regimes access to published articles goes up and scholars can more easily read and cite discovered knowledge. Consequently, scholars can publish new papers more rapidly. The impact of increase in copyright cycles is more dramatic when the required citations are higher. For example, when eleven citations are needed, the number of published papers declines about seventy percent when we extend copyright protection from zero to two hundred cycles, while the drop in publications is only about twenty percent where required citations are five (see graph 1). Although the general trend is intuitive, there are several more specific features of the results that are particularly interesting.

3.3 First, the decline in knowledge creation was steep with respect to increases in shorter copyright terms and relatively flat with respect to increases in longer copyright terms. For example, in the scenario where we require eleven citations, 63 of the 70 percent total decline in knowledge production happens when copyright is increased from 1 to 25 cycles. The curve begins to flatten with respect to increases after 25-cycle point. However, when the required citation is lower, we see a more gradual decrease in knowledge creation. The increase from 150 to 200 cycles has very little negative impact regardless of citation requirements.[16] The same trends also occur with respect to the impact of copyright term on citation rates, where the results are qualitatively similar to those regarding publications.

3.4 Second, increasing the copyright term tends to hurt all scholars. However, the negative impact is significantly larger for scholars with restricted access, leading to large inequalities between the groups. The decline in the publication of AL0 scholars is intuitive because increasing the copyright term means these scholars will have access to fewer articles to read and as the result fewer opportunity to publish. It is, however, interesting to note that most of this inequality typically emerges in the initial increase of copyright term from 0 to 25. And, increasing the copyright term beyond this point tends to, very moderately, reduce both inequality and overall productivity (see graph 2). The same trends hold for citations received. Additionally, the resulting inequalities are most striking in scenarios where more citations are required. For example, with required citations set at eleven and copyright term sets at 50, AL1 scholars are responsible for contributing 92% of total publications.