The FCC/ETSI certification isn't too much of a barrier, being a matter mainly of money. Any manufacturer can pay to have their product tested by a third party

The FCC/ETSI certification isn't too much of a barrier, being a matter mainly of money. Any manufacturer can pay to have their product tested by a third party lab and certified to conform to FCC/ETSI regulations. The real barrier is the spectrum licensing, which is a matter for the operator rather than the manufacturer. These at the rules that say that a particular carrier payed for the exclusive use of a band of frequencies and no one else is allowed to use that spectrum. As I understand it though, the law is reactive, in that the law is not broken by owning a capable device, but by using it. Even then, the enforcement depends on a complaint from the carrier (ie. they have to catch you), but if you get caught the penalties are severe.