A lease does not have to be in writing to create a tenancy - you can have an oral tenancy. If you describe someone as a commercial tenant there is an implication that there is some form of landlord/tenant relationship in existence. Where there is such a relationship, then squatters rights do not apply. Squatters rights ( or adverse possession) arises when a person chooses to acquire title adverse to the actual owners and generally arises after 12 years. It is not nearly as easy as the bar stool lawyers would have you believe.
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