Dr. Christian Czychowski
Boehmert & Boehmer, Partner, Berlin, Germany
In view of the increasing significance of open source licences in the law of software licences and first decisions concerning the most important licences by German courts, a short summary of the enforceability of open sources licences in Germany is given.
I. Introduction in the Copyleft Effect
As Open Source Software becomes more and more popular the risk rises that a company incorporates software in its products (e.g. software controlled machines) that again incorporates code that is not proprietary but derives from an open source project. If the company in such a case does not follow the rules of the respective open source license (e.g. the GPL license being the most popular open source license) severe legal effects might occur. In case the code incorporated into a third software is licensed under GPL, it might be confronted with the so called viral effect: Whereas software under GPL is available free of charge and with open code there are restrictions on the rights granted by the GPL. If one does not follow these restrictions the rights granted by the license will fall back and the company will commit a copyright infringement. This situation has not only been discussed in the Anglo-American world of law but also in Continental Europe, especially Germany where some of the first preliminary injunctions and main court actions have been fought out.
Point 4 GPLv3 regulates the distribution of unchanged copies of a program, point 5 GPLv3 those unchanged copies in source code and point 6 those copies in non-source code, that is object code. These rules include the so-called ‘strict copyleft effect.’ In accordance with this, the licensee is obliged to pass on new programs based on the original computer program only under certain conditions, these being specified in the original licence agreement. The legal categorisation of this effect is disputed, though this point need not be expounded here.