I downloaded PyCharm as a tar.gz archive and extracted it into the /opt directory. When I launched it for the first time, it prompted me to auto-create a /usr/local/bin/charm file. While i was running the launch script as a non-privileged user, i didn't expect it would create the file successfully. However, it did. The owner and group of the /usr/local/bin directory are root, and the permissions are 755, just as normal. I have completely no clue how PyCharm managed to do that.
The OS is Ubuntu 12.04.2 LTS, if that is relevant.