/lib/udev/rules.d/40-eegdev-plugins-free.rules is in eegdev-plugins-free 0.2-3.1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 | # Biosemi ActiveTwo Mk2
ACTION=="add", SUBSYSTEM=="usb", ATTRS{idVendor}=="0547", ATTRS{idProduct}=="1005", GROUP="plugdev", MODE="0664"
|