is it possible to protect .img files?

I was able to create the .img files from osm data and upload it to my Garmin (Nuvi 260) using mkgmap. Does anyone know if it’s possible to lock the .img file created to specified devices?

The following quote is from
http://www.opengeodata.org/2008/01/07/the-licence-where-we-are-where-were-going/

"At present, every OSM contributor agrees that their contributions can be used under the Creative Commons Attribution/ShareAlike licence, version 2 (CC-BY-SA 2.0, for short). This means:

* Anyone can copy OSM data.
* But if you incorporate it into something else, that “something else” also has to be copiable under the same terms and conditions (ShareAlike).
* When you copy it, you have to give credit to the copyright owner (Attribution)."

In light of the paragraphs above, you should not be doing anything other than giving away your maps. Therefore, locking them doesn’t make much sense. If you want to copyright your maps, make them from non “ShareAlike” data, and lock them, there are other much more expensive compilers available for you to use.