A German court has granted a preliminary injunction against security firm Fortinet for allegedly violating the general public licence (GPL) and hiding Linux in its code. The ruling could prevent the security appliance vendor from further distributing its products until it complies with the open source licence.

Fortinet was accused of using cryptographic techniques to conceal the presence of Linux code in its FortiGate and FortiWifi products, as well as not releasing its source code under the terms of the GPL.

The company's use of Linux was deemed by the court to be in violation of the GPL under which Linux is distributed.

The licence allows for the reuse of the code, but requires that developers grant public access to all the source code and provide a copy of the full licence text.