A more thorough explanation:

A first-to-file system is a practice in patent law where the first person to file a patent application is granted priority over others who may have invented the same thing but filed later.

For example, if two inventors come up with the same idea, the one who files the patent application first will be granted the patent, even if the other inventor came up with the idea first.

Most countries in the world use a first-to-file patent system, except for the United States, which uses a first-to-invent system. In the first-to-invent system, the person who can prove that they came up with the idea first is granted the patent, even if they filed the application later than someone else.

One example of the first-to-file system in action is in China, where the number of patent applications has skyrocketed in recent years. This is because the first-to-file system incentivizes inventors to file their applications as soon as possible to secure their rights to the invention.