Every state has their own laws. Interestingly some states advantage squatting with a colorable claim of title. For example if your uncle John leaves you real property in his will that he doesn’t have title to and you notoriously occupy and use that property for seven years you can apply for a clean title. Without that colorable claim you might need twenty years or more.
There are always gaps in emerging economies and this rule is one of the more useful ones to onboard assets into the legal system.
cfr. De Soto - Mystery of Capital