A side effect of Linus Torvalds departure from Linux to reflect on how he treats people and the upcoming Linux Code of Conduct (CoC) is the following question:
What happens if one of the developers is forced to leave Linux? Will he be able to take his code with him, effectively removing it from the operating system? 
The controversy began when someone under the pseudonym “unconditionalwitness” – who had never posted on LKML (from the Linux Kernel Mailing List Archive) – wrote that people forced to leave the Linux Kernel community because of the CoC could “request a grant of their ownership by means of a written notice to those using the code as their property.”
If you’re wondering, no one has been forced to leave the community to date, and there’s no sign that anything like that is going to happen because of the CoC. But there are some people who are worried about what will happen if developers are removed from the Linux community.
Once the code is released, the Linux community logically assumes that the developer will not harm Linux by asking for the right to use the code back.
unconditionalwitness alawyer, does not appear to be a Linux kernel subscriber. The email account he uses comes from some anonymous mail server. So essentially we are talking about an anonymous person who just dropped a bomb. Many Linux developers threatened him but his argument stirred up the stagnant waters (from a code ownership perspective) of the community.
Eric S. Raymond, one of the creators of open source, wrote his own message to LKML:
“This threat makes sense. I looked up the relevant law when I founded the Open Source Initiative, which confirms that reputational damages associated with converting a contributor’s rights to a GPL project are legal.”
Richard M. Stallman, who is the author of the GPLv2 license—the open source license that governs Linux—replied:
“Developers of Linux or any free program may remove any code at any time, without having to give a reason. However, this does not obligate others to remove its code from their own versions of a program.”
While both have made significant contributions to the creation of free software, open source, and the Linux license, they are not lawyers.
In the GPL guidelines from the Free Software Foundation (FSF), open source legal advisor and Columbia Law Professor Eben Moglen states:
In order to ensure that all of our copyrights can satisfy registration and other registration requirements, and to be able to enforce the GPL license in the most effective manner, the FSF requires that every code contributor participating in FSF projects provide a copyright release and, where appropriate, a waiver of any ownership claim for work done for hire by the developer's employer.
Linux, however, does not require its contributors to sign any copyright release.
Karen Sandler, attorney and executive director of the Software Freedom Conservancy, stated: “There is no effective way to revoke code that has been licensed, distributed, and redistributed under the GPLv2. Copyleft is powerful.”
Heather Meeker, partner at O'Melveny & Myers, says:
The legal analysis is a bit complicated, but ultimately an open source license grants rights to any recipient, from the moment the author makes the code available under the license. These rights can be enjoyed by any recipient until the recipient violates the license and loses their rights.
The notion that open source licenses are arbitrarily revocable—because the license is free and therefore not that serious, or because the license is not a contract and therefore does not enjoy the benefits of the dependency theory, or because the author has committed a crime and is in conflict with the code of ethics, or any other theory that could be constructed—emphasizes detail over substance. These arguments will not win, mainly because courts do not like to see intellectual property owners bite the bullet twice.
The idea of revocability was advanced in the 1990s as a FUD technique to scare people away from using open source software.
