Q: Do copyleft licenses permit the use of the general idea of a piece of software?
Say, I read the code of a GPL'd program and wanted to write my own version, not copying any of the code from the program, just utilizing the idea of how it works. Would still be forced to license it as GPL?
Another example is if I wanted to port a GPL'd driver to another kernel. I would not have reused any of the original code, just the general idea. Would I still have to license it as GPL, or does that not count as a derivative and I could use any license I want?
A:
Copyleft licenses like the GPL, which are designed to protect the freedom of code, are governed by specific rules that determine the permissible use of the code. Let me explain the technicalities of your questions.
If you read the code of a GPL'd program and want to write your own version, you can certainly utilize the general idea of how it works. However, you must be careful not to create a derivative work, as this would trigger the copyleft requirements of the GPL. The definition of a derivative work under the GPL is broad, and includes any work that is based on or derived from the original code, regardless of whether the original code is copied.
Therefore, if your new version is found to be a derivative work, you would be required to license it under the GPL. This means that anyone who receives or uses your code must also abide by the terms of the GPL, including the requirement to release the source code and make it freely available.
Similarly, if you wanted to port a GPL'd driver to another kernel, you must be careful not to create a derivative work. Even if you do not reuse any of the original code, the general idea may still count as a derivative work under the GPL. Therefore, you would need to analyze the similarities between your new work and the original driver to determine whether it is a derivative work or not.
If your new work is found to be a derivative work, you would be required to license it under the GPL. This means that anyone who receives or uses your work must also abide by the terms of the GPL.
In conclusion, copyleft licenses like the GPL permit the use of the general idea of a piece of software, but the creation of a derivative work triggers the copyleft requirements of the license. It is important to understand the rules of the specific license and analyze the similarities between your work and the original code to determine whether it is a derivative work or not.
Justia Ask a Lawyer is a forum for consumers to get answers to basic legal questions. Any information sent through Justia Ask a Lawyer is not secure and is done so on a non-confidential basis only.
The use of this website to ask questions or receive answers does not create an attorney–client relationship between you and Justia, or between you and any attorney who receives your information or responds to your questions, nor is it intended to create such a relationship. Additionally, no responses on this forum constitute legal advice, which must be tailored to the specific circumstances of each case. You should not act upon information provided in Justia Ask a Lawyer without seeking professional counsel from an attorney admitted or authorized to practice in your jurisdiction. Justia assumes no responsibility to any person who relies on information contained on or received through this site and disclaims all liability in respect to such information.
Justia cannot guarantee that the information on this website (including any legal information provided by an attorney through this service) is accurate, complete, or up-to-date. While we intend to make every attempt to keep the information on this site current, the owners of and contributors to this site make no claims, promises or guarantees about the accuracy, completeness or adequacy of the information contained in or linked to from this site.
