More explicitely a report from the U.S. Government Accountability Office which had to evaluate previous studies about the impact of pirated goods states right from the summary:
"Some consumers may knowingly purchase counterfeits that are less expensive than the genuine goods and experience positive effects (consumer surplus), although the longer-term impact is unclear due to reduced incentives for research and development, among other factors. Three widely cited U.S. government estimates of economic losses resulting from counterfeiting cannot be substantiated due to the absence of underlying studies. Generally, the illicit nature of counterfeiting and piracy makes estimating the economic impact of IP infringements extremely difficult, so assumptions must be used to offset the lack of data. Efforts to estimate losses involve assumptions such as the rate at which consumers would substitute counterfeit for legitimate products, which can have enormous impacts on the resulting estimates. Because of the significant differences in types of counterfeited and pirated goods and industries involved, no single method can be used to develop estimates."
Basically, it's refreshing to see black on white from an official agency some thought on the basic idea that always seemed more reasonable to me in the face of the "every pirated copy is a stolen copy" camp: not every copied piece of software replaces a bought copy of software.
The report is lengthy, but worth a quick browsing. A few other slightly unusual excerpts:
"consumers may use pirated goods to “sample” music, movies, software, or electronic games before purchasing legitimate copies, which may lead to increased sales of legitimate goods."
Which resounds with me, because I almost always download a copy of software if a proper demo is not available. We might also wonder if having access to a much wider gamut of the offer for testing won't lead to a better selection of the genuinely better products, with further beneficial effects for all the community (increased weight of product intrinsic values versus "external", marketing based ones in sales response)
"For example, some experts we spoke with and literature we reviewed discussed how consumers after being introduced to the pirated version might get locked into new legitimate software because of large switching costs, such as a steep learning curve, reluctance to switch to new products, and search costs incurred by consumers to identify a new product to use."
Which is spun into direct lock-in gains for the software producers, but I may add that can also end up in a bigger value creation for the communtiy at large.
That is: people, especially young people and students, gain a considerable amount of know-how through the use of copied specialistic software. In my field I think of pieces of software like Mathematica or AutoCAD. There are education versions of some of that software, but the pirated version is generally richer in features and more accessible.
All that added knowledge and training has a value, that is translated into a higher quality and value of their work and thus re-enters the economy through the employment of those better trained people.
Well, that's food for thought. I find interesting that the evaluation of the impact of IP piracy is at least being discussed in fair terms, and the doubts on many a priori assumptions are being voiced by an official insttution in the same nation of the ACTA.