Tortious interference is a civil claim against a third party who deliberately disrupts your contract or business relationship with someone else. It gives you a way to sue an outsider who wasn’t part of your deal but intentionally sabotaged it, and it comes in two forms: interference with an existing contract and interference with a prospective economic relationship. Each form requires different proof, and both demand that you show real money was lost.
The Two Types of Claims
The law treats a signed contract differently from a deal that was only on the horizon, and the distinction shapes everything about your case.
Interference With an Existing Contract
This is the stronger claim. When you have a binding contract and a third party knowingly induces the other side to breach it, courts protect those contractual obligations from outside meddling. You need to show the contract existed, the defendant knew about it, the defendant took deliberate steps to cause a breach, a breach actually occurred, and you lost money because of it.1Legal Information Institute. Intentional Interference With Contractual Relations
One limitation matters: an unsuccessful attempt generally won’t support a claim. If the defendant tried to convince your business partner to walk away and your partner honored the contract anyway, you likely have no case, because no breach occurred and no damages followed.1Legal Information Institute. Intentional Interference With Contractual Relations
Interference With Prospective Economic Advantage
This version applies when no formal contract exists yet. You might have been in late-stage negotiations with a buyer, had a long-standing customer relationship you expected to continue, or been the leading bidder on a project. The economic relationship must be one that probably would have resulted in a financial benefit, not just a hope.2Bloomberg Law. Tortious Interference With a Prospective Economic Advantage
Because no signed contract exists to protect, courts set a higher bar for the defendant’s conduct. In many jurisdictions you have to show the interference was “independently wrongful,” meaning the defendant committed some separate legal violation like fraud, defamation, breach of fiduciary duty, or a criminal act. Outcompeting you, even aggressively, isn’t enough. Some jurisdictions take a broader view: interference may be actionable if the defendant acted out of pure malice or used dishonest means that go beyond normal competitive behavior.2Bloomberg Law. Tortious Interference With a Prospective Economic Advantage
What You Have to Prove
Tortious interference is a common law tort, developed through court decisions rather than a single statute. The exact elements vary by jurisdiction, but the core proof is consistent.
You need a valid business relationship with a third party. It can be a signed contract, an ongoing supplier arrangement, or even advanced negotiations likely to result in a deal. The relationship doesn’t have to be ironclad, but it has to be real and identifiable.
The defendant has to have known about that specific relationship. General awareness that you do business isn’t enough. If a competitor poaches your client without realizing you had an exclusive supply agreement, that lack of knowledge undermines the claim.
The defendant must have intentionally and improperly interfered. “Intentional” means the defendant acted with the purpose of disrupting your relationship or knew that disruption was substantially certain to follow. “Improper” is where most of the courtroom fighting happens.
The interference must have actually caused the third party to break off or breach the relationship. A competitor who badmouths you but changes no one’s behavior hasn’t caused actionable harm. And finally, you must prove real financial damages. Courts don’t award anything for interference that hurt your feelings but didn’t cost you money.
What Makes Interference “Improper”
This is where cases are won and lost. The word “improper” does a lot of work, and courts use a multi-factor approach drawn from the Restatement (Second) of Torts to decide whether the defendant crossed the line.
Courts look at the nature of the conduct itself. Fraud, threats, and bribery are almost always improper; persuasion and legitimate competition usually aren’t. They look at motive, weighing whether the defendant was advancing their own interests or acting primarily to harm you. Pure spite weighs heavily toward improper. They balance the interests at stake, measuring your interest in the relationship against whatever interest the defendant claims to protect. They consider how direct the interference was, since a phone call to your client telling lies is more clearly wrongful than general market activity that affects you indirectly. And they consider broader social interests like free competition.
No single factor decides it. A defendant with a legitimate business motive might still be liable if the methods were egregious. A defendant whose motives were partly competitive might escape liability if the means were fair. Courts look at the whole picture.
Common Scenarios
Non-compete recruiting is one recurring pattern. If an employee has a non-compete clause and a rival company knows about it but recruits that employee anyway, the original employer can bring a claim against the rival. The contract existed, the rival knew, and the rival deliberately caused the breach.
Spreading false information is another. A startup is in final negotiations for a bank loan. A competitor calls the bank and fabricates stories about the startup’s finances. The bank pulls the offer. The startup’s claim is interference with prospective economic advantage, independently wrongful because it involved defamation.
A third pattern shows up in commercial real estate. A business holds a lease on a prime location, and a third party wants that space. Bribing the landlord to break the existing lease is a textbook interference case. The wrongful means makes it straightforward.
What Doesn’t Count
Legitimate competition is not tortious interference, even when it’s aggressive. If a competitor wins your client with a lower price, a better product, or faster service, that’s how the market is supposed to work. General advertising that highlights a competitor’s strengths is also protected, even if it costs you customers.
Honest advice falls outside the scope too. If a consultant genuinely believes your vendor’s products are inferior and tells a client to switch, that’s an opinion shared in the client’s interest. The advice has to be honest, though. Fabricated concerns designed to steer business away from you can support a claim.
Defenses the Other Side Can Raise
Even when every element lines up, the defendant may have defenses.
A competitor can invoke the competition privilege. To use it, the defendant generally must show they were actually a competitor, didn’t use wrongful means, didn’t create an unlawful restraint of trade, and were at least partly motivated by advancing their own competitive position.3Bloomberg Law. Justification and Privileges – Tortious Interference: Tort Defenses
A defendant who interferes to protect a preexisting economic interest, such as a lender enforcing a covenant or a shareholder protecting an investment, may be justified. The question is whether the defendant’s interest in the subject matter is equal to or greater than the plaintiff’s interest in being left alone.3Bloomberg Law. Justification and Privileges – Tortious Interference: Tort Defenses
Agents acting on behalf of a principal are often shielded as well. Corporate officers acting in the corporation’s interest, agents protecting their principals, and trustees acting for beneficiaries may all avoid personal liability for interference that falls within the scope of their duties.3Bloomberg Law. Justification and Privileges – Tortious Interference: Tort Defenses Truthful statements and genuine professional advice also generally cannot form the basis for a claim, even when the truth is unflattering and costs you a deal.
In most jurisdictions, justification and privilege are affirmative defenses, meaning the defendant carries the burden of proving them. In some courts, though, the absence of justification is treated as an element the plaintiff must prove, so the procedural burden shifts depending on where you file.3Bloomberg Law. Justification and Privileges – Tortious Interference: Tort Defenses
Damages You Can Recover
The primary recovery is compensatory damages covering what you actually lost, usually the profits you would have earned from the contract or relationship had the interference never happened.4Legal Information Institute. Tortious Interference
Lost profits are where these cases get difficult. Courts require proof with “reasonable certainty,” which means hard evidence: historical financial statements, revenue projections, customer records, and often expert testimony from an economist or accountant. Speculative profits won’t cut it. If you’re a new business without a track record, proving what you would have earned becomes significantly harder. Uncertainty about the exact dollar amount won’t kill your claim, but uncertainty about whether you would have earned anything will. You may also recover for damage to your business reputation if you can show it caused measurable financial losses.4Legal Information Institute. Tortious Interference
When conduct was particularly outrageous, involving fraud, malice, or deliberate cruelty, a court may add punitive damages. Those awards punish and deter rather than compensate, and most interference cases don’t produce them. The possibility gives the claim teeth in egregious situations.4Legal Information Institute. Tortious Interference
If the interference is ongoing, you may be able to seek an injunction requiring the defendant to stop before trial. Injunctive relief becomes more realistic when the harm is continuous or hard to measure in dollars, such as the slow erosion of customer relationships. Speed matters: courts look unfavorably on plaintiffs who wait weeks or months before seeking emergency relief, because delay undercuts any argument that the harm is urgent.
Deadline to File
Tortious interference is subject to a statute of limitations, and the time period varies by jurisdiction, with most states allowing somewhere between two and four years from when the interference occurred. Miss the deadline and the claim dies no matter how strong the evidence.
Many jurisdictions apply a discovery rule that extends the deadline when the interference was hidden. Under that rule, the clock doesn’t start until you knew or reasonably should have known about the interference. That matters in cases involving secret schemes or behind-the-scenes sabotage, where you may not realize what happened until long after the damage. The rule won’t save you if the interference was obvious and you simply waited too long.
If you suspect interference, consulting a business litigation attorney promptly protects both your evidence and your filing window. These claims demand substantial proof: communications between the defendant and the third party, financial records documenting your losses, and often expert analysis. Starting early is almost always the difference between a workable case and a dead one.