Moats. Arcam's patent moat is extensive enough for their powder bed, electron beam technology that I doubt there's a threat on any front. In addition, they have or have pending FAA and FDA or FDA type approval for parts made from their machines. FAA approval requires very specific descriptions of process, so much so that what variability exists in Arcam's processes is a bit of a problem. It's not like casting a part, they're looking at what's going on during the entire build. We're there, the process has been accepted by GE and more. That's the other moat.
I don't know what their original patent was, I'm guessing it's the obvious thing, along the lines of electron beams that melt metal particles to build 3d structures. Say that idea can be freely used. Look at all of the research and work that's needed to even tweak the processes for a new patent that produces competitive metallurgy. We're looking at small changes that can bring a better process to the kind of control they have already. That is not easy and requires lots of expensive experiments and another extensive round of metallurgical research. I'm comfortable with the idea that nothing can challenge what they have to offer in aerospace or orthopedics for at least 5 years.
Don't see why one can't have more than one electron gun but for the added cost I doubt it's justified unless you're building much larger parts or there's an additional level of control that an extra gun provides. Cathode ray tubes for television had 1 or 3 guns depending on the technology and the precision was good enough for the image you got at the time whether using 1 or 3. I have confidence that their engineers are on top of this.
