I just looked up American law and found this.
"Reverse Engineering: University faculty, students, and IT professionals engage in reverse engineering for currently permissible purposes such as research and teaching, debugging, ensuring interoperability between systems, and security testing."
So I think the PDF could actually be legal (in most countrys) if done for debugging & security testing Purposes by IT Professionals or Students etc.
To me the PDF didn't steal anything.
I am so glad that people reverse engineer software to find security risks.
I do not want my Computer System compromised in any way.
I purchase software legally and I am so glad when People with good intentions find the holes before the bad ones do.
I'm from Australia by the way.
Intersting article here
http://lwn.net/Articles/134642/Quote from Article (You got to feel sorry for America with all their teams of Laywers for the rich stuffing up their country just for finacial gain for a few)
"The recent flurry of rulings that reverse engineering of mass-market products is not fair use have tied one arm behind American programmers' backs while leaving everyone else free to compete with us. . . . These days I teach university courses (undergrad through doctoral) as a Professor of Software Engineering at Florida Tech. We have a lot of grad students from other countries. They are often surprised by our restrictions on reverse engineering -- they certainly don't have their hands tied by these restrictions in their companies.
The United States used to have a commanding lead in software development. We have been steadily losing that lead. Part of the reason for this is that for the last 15 years, lawyers for software publishers have been pushing for short-term advantages for their clients over the long term health of the industry. The ban on reverse engineering is just another example -- we are shooting the American industry in the head, with little actual benefit for anyone (publisher or engineer) in the United States, but plenty of benefit for engineers in all the rest of the world. "