Steven Penny had the opportunity to explain his doings:
https://github.com/svnpenn/sage/issues/2
https://github.com/svnpenn/sage/issues/3
https://github.com/svnpenn/sage/issues/4
but choose not to say more than claiming to be the sole developer of apt-cyg.
This apt-cyg project has a history back to 2005, released under GPL by Stephen Jungels (according to the original code) and Stephen is also the owner of the now DCMA:ed GitHub repo.
https://github.com/transcode-open?tab=repositories
When apt-cyg moved from Google Code to GitHub it seems that the license changed from GPL to MIT, most likely a move by Stephen Jungels.
So how can Steven Penny claim rights over apt-cyg? Maybe he did a complete rewrite of the code? One can only guess at this stage.
If he did, feel free to do so, the code was MIT, improve, rewrite, re-label and try to market your version. Thats all in the interest of open source movement. No harm done.
But, it does not seem right, to claim something that has been open source code for more than 10 years. Not even a complete rewrite gives you the power to file a DCMA on open source project.
That does not feel right and such an action can never be a positiv movement for the open source community.
Something is fishy, maybe there is more than meets the eye?
Still, no matter the claim, filing a DCMA on open source code where the project has thousands of active users, well, thats not good for open source.