Wittmann (1991) suspects that LSC may be part of the French Sign Language family, but transmission to Catalonia would have happened early, and is not easy to demonstrate.
Likewise, a Linguistic Professor from the University of La Coruña who specializes in LSC, found that the difference between a language like this and oral languages is the use of "neutral space" in front of the signer when speaking on real life situations as well as the use of visual character.