No idea roughy - but i bet the answer is a lot more complicated than the question suggests (i was a lawyer, but only for long enough to know that i dont know anything!)
As for the 3 years - they might have exclusivity for that long, but surely they'll knock the feasability study off asap - anyone know how long it would take?
And here's an announcement that i liked - Mr Burns is giving up other business interests to concentrate on CNM - hopefully because he thinks his workload is about to take off!