In the UK, the Advertising Standards Authority has ruled against a number of companies for making unsubstantiated claims for some of their stupidly expensive cables. Basically they were convicted of making false claims for their products.
HERE'S the first ruling I found but there are a bunch of others. I particularly like the company trying to use the argument that, since any improvements were subjective, they didn't need to be provable. Sorry...you can prove subjective improvement in a proper blind test (and probably measure the differences).
Frankly I quite like the idea of audiophools being parted from their money but I guess it's good that the cable rip offs are being subjected to the same standards as other companies.