Scienter

Scienter refers to a defendant's knowledge that their conduct was wrongful or that a particular fact existed at the time of the act. In securities law, scienter is a required element of fraud claims under Section 10(b) of the Securities Exchange Act, meaning the plaintiff must prove the defendant acted with intent to deceive, manipulate, or defraud, or with severe recklessness. In common law fraud, scienter encompasses knowledge that a representation is false or a reckless disregard for its truth or falsity. The concept distinguishes intentional wrongdoing from mere negligence or innocent misrepresentation.

Scienter is a critical element in securities fraud litigation, where courts require plaintiffs to plead facts giving rise to a strong inference of fraudulent intent. In animal law, the term historically referred to the owner's knowledge of an animal's dangerous propensity, which was required before strict liability could attach for injuries caused by the animal.