/usr/share/bls-standalone/rulesbinary.switch is in bls-standalone 0.20151231.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 | ## Match: regexp: \(\(/usr/bin/\)\?fakeroot \)\?debian/rules \/binary\(-arch\)\?$
## Action: set rulesmode 3
|