I hate to have just no opinion on it, but it would literally take hours of research for me even to have a sloppy opinion on it, and as long as a week or two to have an actually informed opinion.
Just as a total retard opinion, with no representation of any expertise whatsoever on this subject, it LOOKS like typical patent troll behavior. Both suppressors and 3D printing are established technologies, so-called "prior art." It APPEARS to me, on a very superficial reading, that they are somehow claiming that 3D printing to fabricate a suppressor is, itself, somehow patentable. I find this dubious at best.
I am not expert enough (or at all for that matter) to have much of an opinion on the actual patents themselves. So I'm not going to say your reading is right or wrong because I simply don't know.
The one thing I'm interested in is does this "Centre Firearms" thing even produce anything? Non-practicing entities, i.e. patent owners that don't actually product anything but constantly sue those who do, are your usual patent trolls. A Google search says they claim to produce "products and services" but lots of patent trolls claim that too.
Centre Firearms acquired PTR in April 2020. 90% sure this is their website
https://www.centresupport.com/. Looks like they focus on Mil/LE training and providing blank firing guns, simunition, and sample guns for training. Interestingly their website homepage features a promo video with convicted weapons smuggler Larry Vickers(well known gun industry celeb, ex Delta Force).
A quick search of patents brings up a bunch of odd blank firing and firearms stuff. Relating to PTR, they patented pic rail endcaps for MP5 style firearms a couple years before the acquisition:
Pistol sights that reflect light from the rear into the front, intended to compete with red dots:
And notably a bunch of patents for 3d printed suppressors, this is the earliest one I found, filed in 2013:
They specifically mention
preferably manufacturing it out of plastic through a layered printing process. Outside of the idea to 3d print it, the illustration is very similar to most other suppressors. The only parts that look hard to traditionally manufacture are the secondary holes/ports in the baffles.
PTR didn't sell suppressors before Centre bought them, so I assume these were Centre's idea. Here's a cutaway of a PTR I found on r/nfa
The basic ideas behind their original patent seems very broad. On the public facing side of things 3d printed suppressors have only been around for a few years, but PTR was not the first company to bring them to market. I can only wonder why Centre waited until now to start enforcing the patent.
One more note about 3d printed cans, a lot of companies do not manufacture their own suppressors. Only a few manufacturers have the capability to additive manufacture the metals used in suppressors. Notably Dillon suppressors are manufactured by PTR, Dead Air sources from Radical Defense, and CAT claims to source from an overseas supplier. Its all hidden behind NDAs.
