Can I modify GNU GPL software for my proprietary software application?

last updated in Categories GNU/Open source

I have a client and they have developed a new proprietary software app using open source GPL software.


They were distributing app w/o giving out source code. This is not allowed under GPL. You can modify GPL’d software and include it within a proprietary software app but can not distribute it. Google/Yahoo and many other service providers do use modified GPL’d software. But they simply don’t distribute it to 3rd party.

More resources…

I am glad that they are now distributing source code. If you are in such problem I recommend following resources:

  • Official GPL License – A must read for you.
  • Wikipedia GPL page – You will get tons of information here.
  • Understanding Open Source and Free Software Licensing by Andrew M. St. Laurent – This is an excellent book explains your licensing options, how they compare and interoperate, and how license choices affect project possibilities. If you’re an open source/free software developer, this book is an absolute necessity.
  • Open Source Licensing: Software Freedom and Intellectual Property Law – A complete guide to the law of open source for developers, managers, and lawyers
  • Producing Open Source Software: How to Run a Successful Free Software Project

And simple answer to this question is NO 🙂

If you have more resources or suggestion please feel free to leave a comment.


Posted by: Vivek Gite

The author is the creator of nixCraft and a seasoned sysadmin, DevOps engineer, and a trainer for the Linux operating system/Unix shell scripting. Get the latest tutorials on SysAdmin, Linux/Unix and open source topics via RSS/XML feed or weekly email newsletter.

1 comment

  1. If anyone has such a requirement, using a software with BSD License will do the trick.

    By the way, the link to GPL in the line ‘Official GPL License – A must read for you.’ does not work.

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