Bob constructs a fence on his neighbor's land without their knowledge and claims it after 15 years. What happens to that land?

The concept of adverse possession is pivotal in this scenario. Adverse possession allows a person to claim ownership of land under certain conditions if they have occupied the land without permission for a significant period, typically defined by state law.

In this case, Bob has constructed a fence on his neighbor's land and has maintained possession for 15 years. This duration often satisfies the requirement for adverse possession, as many jurisdictions require continuous and uninterrupted use of the property for a statutory period, which can range from 5 to 20 years depending on local laws.

For Bob to successfully claim the land through adverse possession, he must demonstrate that his use of the land was open, notorious, exclusive, and hostile, meaning that he used the land without the owner's consent and in a way that sufficiently publicizes his claim. If these conditions are met, Bob can indeed become the legal owner of that land despite having originally trespassed.

Therefore, if Bob satisfies all necessary conditions of adverse possession, the land is legally considered his after the prescribed period, regardless of the neighbor's prior ownership.