GPL Enforcement
The FSF holds the copyrights on many pieces of the GNU system, such as GNU Compiler Collection. As holder of these copyrights, it has the authority to enforce the copyleft requirements of the GNU General Public License (GPL) when copyright infringement occurs on that software. While other copyright holders of other software systems adopted the GPL as their license, FSF was the only organization to regularly assert its copyright interests on software so licensed until Harald Welte launched gpl-violations.org in 2004.
From 1991 until 2001, GPL enforcement was done informally, usually by Stallman himself, often with assistance from FSF's lawyer, Eben Moglen. Typically, GPL violations during this time were cleared up by short email exchanges between Stallman and the violator.
In late 2001, Bradley M. Kuhn (then Executive Director), with the assistance of Moglen, David Turner, and Peter T. Brown, formalized these efforts into FSF's GPL Compliance Labs. From 2002-2004, high profile GPL enforcement cases, such as those against Linksys and OpenTV, became frequent.
GPL enforcement and educational campaigns on GPL compliance was a major focus of the FSF's efforts during this period.
In December 2008 FSF filed a lawsuit against Cisco for using GPL-licensed components shipped with Linksys products. Cisco was notified of the licensing issue in 2003 but Cisco repeatedly disregarded its obligations under the GPL. In May 2009 FSF dropped the lawsuit when Cisco agreed to make a monetary donation to the FSF and appoint a Free Software Director to conduct continuous reviews of the company's license compliance practices.
From 2003 to 2005, FSF held legal seminars to explain the GPL and the law around it. Usually taught by Bradley M. Kuhn and Daniel Ravicher, these seminars offered CLE credit and were the first effort to give formal legal education on the GPL.
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