I remeber a question on a practice exam about patents. Does anyone know how long they are good for? I think the choices were 14, 17, or 20 years. The second part of the question was asking how many years you can amortize a patent. I think it was 40 years?
http://www.investopedia.com/terms/p/patent.asp most patents in the US are valid for 17 years.
so by combination 17 years validity, 40 years amortization… Good to know.