Although it is very difficult to find purebred Wagyū cattle outside of Japan, it is even more difficult to find genuine beef in the trade.

Dishonest sellers use many tricks to disguise the dubious origin of the meat they sell and make a fortune from unsuspecting consumers. Often, meat of other breeds is imported from Japan and then attempted to be sold as premium Wagyū. Remember, Wagyū A5 and A4 come exclusively from the Kuroge Washu breed.

Also note the Japanese name:

• Kokusangyu, 国産牛 - homemade beef, is any beef produced in Japan, if someone sells it as Wagyū then they are just a scammer,
• Wagyū, 和牛 - Japanese cow, only from four specific breeds, if it is to be highly marbled (A4, A5) it must be from the Kuroge Washu breed.