Patent cliff

Okay, so you know how sometimes you make a really cool drawing or build something awesome with Legos? Well, imagine that you were the only one who knew how to make that cool thing and no one else could copy it because it's your special creation. This is kind of like a patent - it means that someone has made something really special and they get to be the only ones who can make it for a certain amount of time.

Now, let's pretend that you made a really special Lego set and it's been really popular for a long time. But, after a while, people start figuring out how to make something very similar to your Lego set. They can't make the exact same thing because it's still your idea, but they can make something close enough that people might start buying theirs instead of yours.

This is kind of like what happens during a patent cliff. When a company invents something really amazing, they get a patent that protects their invention for a certain amount of time. But eventually, that patent runs out and other companies can start making something similar. This means that the company that originally made the invention might lose money because people are buying the new, similar thing instead of theirs.

So, a patent cliff is a time when a lot of patents for really important inventions all end around the same time. This can be a big problem for the companies that own the patents because they might all of a sudden start losing money because other companies can start making similar things. It can be kind of like a cliff because the company's profits might drop suddenly and they have to figure out how to keep making money with new inventions instead of just relying on their old one.