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One potential option is threaten or file a slander of title action. Slander of title is a claim involving real estate in which one entity falsely claims to own another entity’s property. It can also be casting aspersion on someone else’s property business or goods. It can be defined as “a false and malicious statement, oral or written, made in disparagement of a person's title to real or personal property, or of some right of his, causing him special damage."
The essential elements of a slander of title cause of action "are the uttering and publication of the slanderous words by the defendant, the falsity of the words, malice, and special damages." [Donald M. Paterson, Inc. v. Bonda, 425 So. 2d 206, 208 (Fla. 4th DCA 1983)]In order to establish the elements of slander of title, the plaintiff must prove that the defendant has communicated to a third party a false statement disparaging title which has caused the plaintiff actual damage. [Residential Communities of Am. v. Escondido Community Ass'n, 645 So. 2d 149, 150 (Fla. 5th DCA 1994)
Malice is presumed if the disparagement of title to real property is false, causes damage, and is not privileged. However the presumption of malice can be overcome by the showing of privilege. A showing of privilege rebuts the presumption of malice and the plaintiff must then prove actual malice in order to recover in a slander of title action. The affirmative defense of good faith raises a privilege and creates a factual issue as to the existence of malice. Allington Towers Condominium N. v. Allington Towers N., 415 So. 2d 118 (Fla. 4th DCA 1982).
Please consult a local real estate attorney in your area to protect your rights and interests.