On Wed, 12 Dec 2012 17:27:03 +0100 Vo Minh Thu <noteed@gmail.com> wrote:
I'm not sure what your point is.
Re-implementing an algorithm is not a copyright infringement (nor is a propagation of the original work). Algorithms are not covered by copyright.
While algorithms aren't covered by copyright, *code* is. A translation of a copyrighted work into another language is considered a derived work of the original. If not, then simply translating a source program into some computer's binary language would release it from copyright, and it could be freely distributed. That would pretty much kill the GPL. Once someone has read an algorithm in some programming language, it opens the question of whether they are copying the algorithm or the code if they produce a copy of the algorithm. The generally accepted solution is the one taken here - a clean-room re-implementation by people who haven't read the code (ok, sort of taken here). It might be small enough to get by on a "fair use" clause. The "prior art" and "obvious" exceptions stated on this thread are for patents, and don't apply to copyright. But that's all irrelevant. The reason company lawyers object to having GPL'ed code in the company code base is that it opens them up to the possibility of a lawsuit. That the original author said it was derived from GPL'ed code was sufficient to cause at least one lawyer to believe that a case existed. <mike -- Mike Meyer <mwm@mired.org> http://www.mired.org/ Independent Software developer/SCM consultant, email for more information. O< ascii ribbon campaign - stop html mail - www.asciiribbon.org