Can you patent that? Should you?

General John T. Thompson invented that eponymous .45 caliber submachine gun, first produced in 1921. Now, Transformational Defense Industries Inc. is making a splash in military procurement circles with a .45 caliber submachine gun.

It's pitch is that "the recoil is mitigated by diverting the spent gas from a fired round down and away from the gun's firing line. This 're-vectoring' also helps reduce the severe muzzle climb that comes with such high-caliber, high rate-of-fire weapons, helping shooters keep the rounds on target."

Presumably, they are, of course, seeking a patent on their product. There really isn't anything extraordinary about this, indeed, this is really about as ordinary as it comes in patent law, which is notable because it illustrates something about the nature of the beast.

Obviously, TDI can't get a patent on the .45 submachine gun idea. Indeed, it isn't as if recoil reduction is a new concept either. There are numerous U.S. patents, mostly spent and now in the public domain, that attempt to solve the problem.

This also doesn't involve any signficant recent advances in science or chemistry. The physics have largely been in place since Isaac Newton (indeed, one of the important weapons designers of historical submachine guns was named after Isaac Newton). Benoît Paul Émile Clapeyron came up with the ideal gas law in 1834, which is an imperfect, but quite servicable approximation of the behavior of the kinds of gases involved in this system. The ammunition itself isn't that different in basic chemistry from the one used in the Colt .45 pistol in 1911.

I'm sure experts in the history of guns could pin down the dates might tightly than I have, but suffice it to say that the TDI weapon does not rely on quantum mechanics, general relativity, superconductors, or anything so exotic. Probably the most advanced scientific advances it relies upon are apparently plastic parts and improved metallurgy methods that produce better quality materials.

This isn't to say that there isn't room for new invention in the world of relatively low technology items. Shaped skis have had immense impact on that field of endeavor, despite the fact that it would have been possible to make skis utilizing the concept a couple of centuries ago.

But, in every low technology invention, "non-obviousness" is a serious hurdle, because every great invention seems obvious once you have mastered it. Distinguishing this idea from prior art is also not easy. There is a lot of prior art to sift through, and it is entirely possible that some terribly bright person with no business sense invented the idea decades ago, but that poor promotion efforts kept anyone from noticing this fact until it was buried deep in the archives of the patent and trademark office. Now that the idea has been splashed all over the industry, there will be significant rewards for anyone who can defeat the patent by finding a dusty old, now public domain patent, or ancient magazine article that discusses the concept, even if it was the concept was never mass produced.

Also, reliance on any patent for your business profits is a term limited proposition. A patent lasts twenty years from the time that the application is filed (previously 17 years from issuance, although the details are complex). This is not a long time in the world of military and law enforcement procurement. It could easily take a decade from the filing of a patent application before the first large purchase of the weapon is made, if it is indeed any good, and a public patent filing, combined with a purchase of just one copy of the product would make imitation child's play. Also, it can take years to shut down an alleged infringer in litigation, and any litigation can be expensive, even if you win. If an alleged infringer can make a non-frivilous, but ultimately losing argument, you will be in litigation until the bitter end.

These aren't the only challenges involved. Government regulatory restrictions on automatic weapons leave the initial design with a very limited potential pool of purchasers. Efforts to civilianize the weapon will likely lead to efforts to change the law to prohibit that effort. Law enforcement does not have a dire need for a .45 caliber submarine gun with less recoil. A few SWAT teams might be interested, but law enforcement tends to be more interested in pistols and less lethal weapons. Most police and sheriff's deputies do fine with a small sidearm and a shotgun or conventional rifle in the squad car. The core markets for civilian guns sales are for handguns for self-defense and for hunting weapons -- this is neither.

To make military sales the company has to convince buyers that they need this rather than heavier weapons (such as rocket propelled grenade launchers), rather than better established military assault rifles with a different caliber ammunition, and rather than weapons like existing carbines. Even if this does fill a niche, someone marketing an idea like this has to consider how much of a mark up the well established market for small arms will tolerate.

The designers face strict liablity in tort if a defect in the product design or manufacturing kills or injures people using the weapon as intended (as opposed to intended targets), a risk that must be insured against.

In short, even if the idea is solid, making it a viable business proposition is not easy.