IIRC, and I mat be wrong, but I did do a bit of research into some ideas I had (ended up not be cost effective to patent or produce at the time, especially as I would have had to get FDA approval) That utility patents are for 9 years initially, but with the fees mentioned can be extended a few times to a total of 20 years.

I would think with the nature of 3d printing, of all types, that a company would be better off to license their IP, taking a cut of every one produced regardless of who made it, and going after companies that are infringing.

FYI, Design patents are cosmetic only. IE, the Iphone home button I believe has a design patent on it. While other companies can make a phone with a single button on the bottom, it's can't be round with a square in it. A lot of desktop icons (like the infamous circular rainbow) are also design patented. They don't regulate function, just form.

Of course, Patent laws differ from country to country, and while they are somewhat internationally regulated and reciprocated, One country's patent usually doesn't cover another. So if you have a product that is international, you have to file patents in many countries to get protection, and places like China often won't award patents to foreign companies, holding out for a domestic company to file something similar so they can produce it.