A few months back I released some MATLAB code I contributed to MATLAB central under GPL. But the Mathworks sent me the e-mail early May

Dear Aravind Seshadri,

Starting later this month, the MATLAB Central File Exchange will adopt the well-known and widely used open-source BSD License as the standard license for posted content. As a File Exchange contributor, you are receiving notice of this new policy in advance of its implementation. No action is required now. We'll contact you again when a FAQ list is available and you are able to update your existing files.

Adopting a standard license for the File Exchange will help eliminate confusion around things such as modification rights, redistribution rights, author liability, and support responsibility. The community's needs in these areas are well served by the BSD license. We need your help to make this happen.

Starting in mid-May, new File Exchange submissions will be licensed under the BSD license as a condition of upload. You may then assign a BSD license to your existing submissions. A simple form-based tool for you to convert your existing files will be available at the File Exchange.

As of July 17, I have re-licensed all my submission to the MATLAB central to BSD open-source license. The codes can be downloaded from this following page.

We want to thank you for contributing your work to the File Exchange. You and other contributors have made the File Exchange a great resource for the MATLAB and Simulink community worldwide.

Sincerely,
The MATLAB Central Team

I was disappointed that they did not let me keep my existing submission under GPL. At times I was kinda angry. Later on in mid June they sent an another e-mail which was much more forceful and made me even more mad.

Subject: Please remove non-BSD license terms from your File Exchange contributions before July 17

Dear Aravind Seshadri,

We noticed that some of your contributions to File Exchange may contain a
non-BSD license. We'd like to keep these on the site, but since we are
standardizing on the BSD license, you will need to remove any other
licenses from your submissions. If you can't re-license your submissions,
or if you choose not to, we're going to have to remove them.

We plan to remove all contributions containing non-BSD licenses on 17 July
2009. Please update your submissions, removing any existing licensing
statements. They will be covered by the new BSD license, applied when you
update. More information about our license policy is available in the File
Exchange Licensing FAQ:

http://www.mathworks.com/matlabcentral/FX_transition_faq.html

Here are the contributions we've flagged:

* http://www.mathworks.com/matlabcentral/fileexchange/10351
* http://www.mathworks.com/matlabcentral/fileexchange/10429
* http://www.mathworks.com/matlabcentral/fileexchange/22763

The easiest way for you to make these changes is to:

1. Click on each link above.
2. Log in if you need to (upper right corner of the page).
3. Click "Download Now" and save your file.
4. Remove your licensing statements.
5. Click "Update File" and attach your new version.

Thanks for giving this your attention.

Sincerely,
The MATLAB Central Team

This led me to express my frustration to my brother who makes his living writing proprietary software. After a lengthy argument, Yaadi Yaadi Yaaaa, he convinced me that BSD license is much more effective form of open-source license compare to the GPL for my particular case. Since I have no interest in maintaining my code anymore, it would be beneficial to release my code as a BSD license because there is a possibility that someone paid to write codes will maintain it (unlike me).

Effective July 17, I re-licensed all my submissions, to MATLAB central, to BSD open-source license. All my submission can be found here.