A ‘trap street’ is an insignificant but telling error purposely introduced by map-makers into hardcopy maps to obtain copyright protection. Also called “fingerprinting” technique, it is designed to detect unwary plagiarists without inconveniencing map readers.
In 2001, Ordnance Survey won £20 million from the Automobile Association for unauthorized copying, thanks to its ‘fingerprints’.
From Live Journal < Del.icio.us/ChrisDodo.