Truth be told, it is against the law (in the US) to advertise something that is false, commercially. That includes fake lineages, belts, etc.
But the burden is on someone paying another to make a claim that the person accepting the money accepted it under false pretenses, i.e. fraud.
www.ftc.gov
There are ways to report any business owner in America who is selling martial arts services. But, proving the advertiser is actually lying can be difficult given the chaotic webwork of martial arts lineages and pedigrees.
So yeah, you can't go around advertising that you trained with Bruce Lee, and offer classes for cash, or someone can easily sic the FTC on your butt.
But Jimmy Lee is not committing fraud when selling this book (one of the best on Wing Chun I've ever owned). Bruce Lee practically wrote the whole thing, but gave credit to Jimmy (gymnast, wrestler, boxer, before he became Bruce's student in WC and JKD).
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