/lib/udev/rules.d/40-libhackrf0.rules is in libhackrf0 2013.07.1.16.d5cebd-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 | ATTR{idVendor}=="1d50", ATTR{idProduct}=="604b", SYMLINK+="hackrf-%k", MODE="660", GROUP="plugdev"
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