Like, if I decided to build my own engine, is there patents on the specific parts? Could Toyota sue and say "hey, that camshaft is rather similar to ours" etc.
What do you mean by build? Assemble from off the shelf parts? Because if you do that, no they cannot sue - you bought the parts. Legally. There are two ways to obtain legal access to something that is patented (and is still under patented protection, patents only last 20 years from filing). The first way, is to buy it from the company. In other words, order the part off of Amazon, or straight from a BMW parts vendor for example. In this case, the cost of the patent is baked into the sale price, because you paid the company for the part.
The second way, is to buy it from the company, but differently. In the second way, you pay for access
to the patent directly. This is "licensing". You come to an agreement with the corporate lawyers of, for example BMW. You hash out a contract, and you pay them for the ability to make and sell their idea. Some people don't actually make and sell anything, they just patent the invention, and then license other people to make it. In some cases, that's a patent "troll", but not always.
Patents are not enforced by the police (unlike copyright). They're enforced by the patent holder. So if you stole Toyota's idea, and then walked up to the police and said "Toyota has a patent on this, and I made it and am selling it anyway". They'd be like "uh.... why are you in my squad car, and how did you even get in... that door was locked!". You could even ship a detailed explanation to the FBI of your patent infringement, and they'd ignore it (presumably to chase after copyright offenders). It's
Toyota that has to enforce it. It's
Toyota that has to send you a cease and desist letter, and sue you in civil court.
The reason I bring this up is that if you're just making this for yourself, there is no way that anyone is going to know (probably including you) whether you violated any patents. Because they'd need to actually buy a copy and tear it down in order to figure out how it worked to see if you infringed their patent. And what's more, they'd have to actually
care to spend the money to do that. Which they won't, if you're just making it for you.
And what's even more, they won't recoup any damages in court if you were offending, because you didn't sell it and make millions off of their invention. Now, if you put your instructions on youtube and a bunch of people start doing it, you might raise some eyebrows.
Getting back to your question, Toyota wouldn't sue and say "that camshaft is rather similar to ours". They'd sue and say "that camshaft has an elongated protrusion which is rotatably attached to a crossmember wherein the crossmember has a circular cross section with a gap blah blah blah just like our patent claims say". Actually they'd start out with a cease and desist letter and potentially follow it by suing for damages (lost revenue from the patent).
Like, side airbags and ABS are newish things yeah? Like they were both options on my mom's 2003 Neon, is ABS patented by someone else and would I have to apply/ask for permission and pay to use ABS?
It's likely far more complicated than that. ABS is likely patented by
everyone (or was, and then expired 20 years after filing). I'd guess that BMW has a suite of ABS patents, and Ford has a suite of ABS patents, and Toyota has a suite of ABS patents, and maybe Volkswagen licenses the BMW ABS patents in the US, but not in Germany where they do something else.
If you invented a new ABS system, what you might want to do before selling it is to try to patent it. The USPTO would search your invention and return a bunch of relevant patents to you (with an explanation for why you're not entitled to a patent), and you could look through those to see whether you infringe someone else. If you think you don't, you narrow the scope of your claims and try again until you get a patent issued. You'd want an attorney to look through the relevant patent documents to see whether you infringed (or if they were expired, or not relevant in the US or whatever). Attorneys can also do this "clearance" search for you.
It was a stray thought when I realized how many features/options are shared amongst car companies and in terms of the tech industry... It's like any stray thought is patented and any similar technology is chased after hard.
What tends to happen is that someone gets a big valuable patent on a new technology, and then others pile on with tiny modifications to it and try to clear the bar of
obviousness. Which is not as easy as it sounds.
Actually what tends to happen is that you file a patent application, spend a few thousand dollars prosecuting it with the USPTO until you get one issued, and then you try to sell it, and it doesn't net you any money, and you abandon it. Most patents just end up abandoned, like mine.
