If you're of a certain age and specific interest--meaning over 35 (mostly) and into nerd stuff--you've likely seen at least one episode of Mystery Science Theater 3000. While primarily about riffing on exceptionally bad movies, there are interludes with the show's characters. Sometimes, they feature regularly occurring bits, like the invention exchange. This bit was most common in the earlier seasons with Joel Hodgson.
Of course, none of the inventions are remotely serious, but they do offer a fun way to investigate the aspects of patentability.
Patentability is, at its most basic, whether or not an invention is eligible for a patent. And, again at a basic level, patentability is determined by three qualities: new, useful, and non-obvious. There are other rules, like nothing that would be better categorized as another kind of IP, nothing illegal or "offensive to public morality", no natural phenomena, or laws of nature. But we can typically stick to the three qualifications here.
New: it can't be something previously disclosed. So if you invent a new machine, and then publish an article about its details, share them on social media, or make them available at a conference, it's not new. Keep you inventions secret! Also, if you spill the secrets or someone comes up with the same/similar concept and files for a patent first, it's not patentable, because patents are granted to the first to file.
Useful: is must have a purpose. The purpose does not need to further humankind of advance technology, it can include fun or novelty. So perpetual motion machines are out, but a scuba diving kit modified for a dog isn't.
Non-obvious: it can't be obvious. That means that a "person with ordinary skill in the art" (the technical term for a person familiar with the field of the invention, or who works in that field) could not have immediately or easily conceived of the idea. Basic improvements or simple changes to previous inventions are therefore not patentable, but an alteration that makes a significant difference in its function would be.
With those defined, let's look at an invention exchange and comment on their patentability!
Ok, we have an air freshener mobile and a baby teether/Alien face hugger. I'd say that both may once have been patentable. Why? The air freshener mobile has, to the best of my knowledge, not been created before this; unfortunately if neither character applied for a patent it's too old now. It's also very useful! Babies make lots of stinky smells and mobiles are a common baby product. And it definitely isn't obvious, because it's just a little too weird to be obvious. As for the teether/face hugger, that meets the same new (at the time) requirement. It is also very useful because it's good for baby and very entertaining for adults, meeting at least the novelty standard. Finally, it's obvious, in my opinion, but again probably because it's just so weird.
Let's do another!
The "Chinderwear" is maybe patentable, but wouldn't be a strong patent. Ignoring the fact that none of these count as new anymore (which I will from here on out), it may not be considered useful. Why? Because the chin butt isn't something people typically want to cover. As for non-obvious, if we really considered cleft chins as butts, it would be too obvious. So the usefulness of the invention negates its non-obviousness. The Rat Pack chess set falls prey to a rule that isn't covered by the three basics above. Using name, image, or likeness of a person requires direct authorization if they're living; for a deceased person, if it is already being used in other intellectual property (I will assume that's the case for such well-known people) then it's already owned and would also require some kind of permission. Furthermore, it's a little obvious. This isn't a strong case of being too obvious, but the change to the chess set is so simple that it may be marketable but not patentable.
One more?
This clip inspired this post, so I had to include it. The super schnozz isn't patentable because, as was pointed out by Joel and the robots, it's not useful. At all! I don't think it could even count for novelty. Perhaps it could claim a design patent, but not utility. It's also kind of obvious, because it's just a big nose, and that's an obvious thing to make. The same problems plague the big head: not useful, pretty obvious. I'm sure someone has before decided to make a big head, maybe for one of those giant foam hats, so it probably isn't new, either. Stick to the baby items, gentlemen.
Yes, I was feeling a bit silly when I came up with this topic. And as it's almost winter recess, it's a good time to be silly.