Mako says

Greg Pomerantz pointed me to this article on a recent 2nd Circuit copyright decision. The case basically disambiguated the term "owner" in 17 U.S.C. §117 (a). It may seem nit-picky and obscure but (AFAICT, IANAL, OMG) this decision has good implications for free software hackers.

and

The case in question is Krause v. Titleserv Inc., 03-9303. Here is the back story: William Krause was a programmer and consultant hired by Titleserv to write a series of programs over the course of a decade. When Krause left Titleserv, he left the company the right use the software but not modify it. Using technical means that are not entirely clear from what I've read, he left the software "locked" so that the company did not have access to source code or the ability to modify the program. Evidently, the technical means were not very good ones. Titleserv managed to sidestep these restrictions and bring the software back into modifiable source form. They modified the program to keep it working a number of times and in a number of sometimes rather intrusive ways.

Second Circuit Judges Pierre Leval and Robert Katzmann sided with Titleserv. Leval said that courts should, "inquire into whether the party exercises sufficient incidents of ownership over a copy of the program to be sensibly considered the owner of the copy for purposes of §117(a)." Rightful possession is ownership.</blockquote>

Seems like a landmark case. If you have rightful possession of a program - then you own it and can freely modify it. This is huge!

If you're really interested, here is another article and you can find the full case on Lexis and elsewhere.