>>10
Public domain by definition cannot be patented.

However some countries have difficulties of allowing their citizens to public domain their own works. Apparently they believe that they own the people thus they get to decide if your work can be public or not. :)

I'm just glad that patent offices where invented late in our history. Imagine if the wheel and how to make fire where patented. Not to mention all the construction methods.

On todays fast moving world there is no legitimate reason to allow patents of more than 7 years.