The person who holds the greatest ownership rights in a property allowed by law owns a:

The fee simple estate represents the highest form of property ownership recognized by law. When someone owns a property in fee simple, they have complete control over the property, including the right to sell, lease, or bequeath it to heirs. This type of ownership is characterized by the absence of any limitations or conditions; the owner can do essentially anything within the bounds of the law.

This ownership is distinct from other forms of property ownership. For instance, a leasehold grants the tenant certain rights but is limited in duration and subject to the terms of the lease agreement. A life estate provides rights limited to the lifetime of an individual, after which the property passes to another party, not allowing for full control by the owner. A defeasible estate can be revoked or "defeated" based on certain conditions not being met.

Thus, the fee simple estate signifies the greatest bundle of rights in real property, giving its holder the most freedom and control over the property in question.