Summary. When a competitor hires away a sales team, a supplier stops shipping after a rival calls, or a customer walks mid-contract, the claim businesses reach for is tortious interference — and it is the claim they most often lose, because competition is privileged. This article covers both interference torts element by element, the competition privilege and the independently wrongful conduct requirement, and the justification defenses. It then covers adjacent claims — unfair competition, fiduciary duty and aiding and abetting, conspiracy, unjust enrichment — and the preemption and economic loss doctrines that eliminate several of them, plus proof, damages, injunctions, and defenses.

A regional insurance brokerage loses four producers to a competitor in a single month. They take their books of business with them; roughly $2.1 million of annual commission revenue follows.

The brokerage sues the competitor for tortious interference. Its theory is intuitive and, as pleaded, insufficient: the competitor knew the producers had client relationships, solicited them, and took the business.

The competitor's answer is that this is what competition looks like. The producers were at will. Their client relationships were not contracts. Recruiting employees, including groups of them, is lawful. And absent an enforceable restrictive covenant, a trade secret, or some independently wrongful act, hiring someone's best people is a market outcome, not a tort.

The brokerage's case survives — but only because discovery reveals that one departing producer downloaded the client list to a personal drive two weeks before resigning, and that the competitor's regional manager knew and asked for it.

That is the shape of nearly every interference case. The conduct that everyone finds objectionable is usually privileged. The case turns on some independently wrongful act sitting inside it, and the entire litigation is a search for that act.

The short answer

Two distinct torts, and the difference matters:

  1. Tortious interference with contract — the defendant induced a third party to breach an existing contract with the plaintiff. Elements: a valid contract; the defendant's knowledge of it; intentional and improper interference inducing breach; actual breach or disruption; and damages.

  2. Tortious interference with prospective economic advantage (or prospective contractual relations, or business relations) — the defendant interfered with a relationship that had not yet become a contract. Elements are similar, but most states additionally require that the defendant's conduct be independently wrongful — unlawful by some measure other than the interference itself.

The competition privilege. A competitor may lawfully divert business from a rival. Restatement (Second) of Torts § 768 provides that one who intentionally causes a third person not to enter into a prospective contractual relation with a competitor does not interfere improperly if the relation concerns a matter of competition, the actor does not employ wrongful means, the action does not create or continue an unlawful restraint of trade, and the actor's purpose is at least in part to advance its own competitive interest.

The single most important structural point: the privilege is much stronger for prospective relations than for existing contracts. Inducing breach of a binding contract is rarely privileged; competing for business not yet under contract almost always is.

At-will contracts occupy a middle ground. Most states treat interference with an at-will contract or employment relationship as governed by the prospective relations standard, requiring independently wrongful conduct, on the theory that a party free to terminate at any moment has no protected expectation of continuation.

Interference with contract

A valid contract. Any enforceable agreement, including one terminable at will in most states (analyzed under the prospective standard), and including a contract voidable by the third party. An unenforceable agreement — void as against public policy, or barred by the statute of frauds in some states — generally cannot support the claim. This is why an unenforceable non-compete frequently defeats an interference claim built on it: if the covenant is void, the "breach" the defendant induced was not a breach at all.

Knowledge. The defendant must know of the contract, or of facts that would lead a reasonable person to believe it exists. Knowledge of the precise terms is not required, but knowledge that some contract exists is. This element is why plaintiffs send notice letters: a competitor that hires an employee and is then told in writing about the restrictive covenant cannot claim ignorance from that day forward.

Intentional and improper interference. Intent means the defendant either desired to cause the breach or knew it was substantially certain to result. Improper is the contested element, and most states use the seven-factor balancing of Restatement (Second) § 767:

  1. The nature of the actor's conduct;
  2. The actor's motive;
  3. The interests of the other with which the conduct interferes;
  4. The interests sought to be advanced by the actor;
  5. The social interests in protecting the actor's freedom of action and the other's contractual interests;
  6. The proximity or remoteness of the conduct to the interference; and
  7. The relations between the parties.

Some states dispense with the balancing and require the plaintiff to plead and prove independently wrongful conduct even for existing contracts; others treat "improper" as an affirmative defense the defendant must establish as justification. The allocation of the burden is state-specific and can decide a case on summary judgment.

Breach or disruption. Most formulations require an actual breach; some accept conduct rendering performance more burdensome or expensive. Where the third party's performance was excused, or where it terminated in accordance with the contract's own terms, there is no breach and no claim.

Causation and damages. The interference must have caused the breach — a third party who was going to breach anyway breaks the chain.

Who can be a defendant. A party to the contract cannot tortiously interfere with its own contract; its liability is for breach. This is why the tort is pleaded against outsiders, and why plaintiffs frequently attempt to reach a contracting party's officers, agents, or affiliates individually. Most states hold that an agent acting within the scope of authority and in the principal's interest is not a stranger to the contract and cannot be liable — unless the agent acted for personal benefit or outside the scope of the agency.

Interference with prospective economic advantage

The elements track the contract tort with two differences.

A reasonable probability of a business relationship. Not a mere hope. Most states require an identifiable prospective relationship with a specific third party and a reasonable probability that it would have been consummated. "We would have gotten more customers" fails; "we had a signed letter of intent and a scheduled closing" does not.

Independently wrongful conduct. The majority rule, articulated influentially in Della Penna v. Toyota Motor Sales, U.S.A., Inc., 902 P.2d 740 (Cal. 1995), and refined in Korea Supply Co. v. Lockheed Martin Corp., 63 P.3d 937 (Cal. 2003), requires the plaintiff to plead and prove that the defendant's conduct was wrongful by some legal measure other than the fact of interference itself — a statute, a regulation, the common law, or a recognized standard of trade or professional conduct.

Conduct that qualifies as independently wrongful:

  • Fraud or misrepresentation to the third party.
  • Defamation or trade libel.
  • Trade secret misappropriation.
  • Breach of fiduciary duty, or inducing one.
  • Threats, coercion, intimidation, or economic duress.
  • Violation of a statute — antitrust, unfair trade practices, or a licensing statute.
  • Bribery of the third party's agent.
  • Physical interference with the plaintiff's business.
  • Unlawful boycott or concerted refusal to deal.

Conduct that does not qualify:

  • Offering better prices or terms.
  • Recruiting the plaintiff's employees, absent a valid covenant or a trade secret issue.
  • Truthful statements about the plaintiff or its products.
  • Refusing to deal with the plaintiff unilaterally.
  • Aggressive, persistent, or even unpleasant sales conduct.
  • Advising a party of its legal right to terminate a contract.

The at-will overlay. Because most states apply the prospective standard to at-will relationships, and because most employment and many distribution relationships are at-will, the independently wrongful requirement governs the great majority of real-world business disputes.

Justification and privilege defenses

Even where the elements are met, several privileges defeat liability.

Competition, Restatement § 768, described above. The defense fails if the defendant used wrongful means or acted with a predominantly improper purpose — spite or destruction rather than competitive gain. A defendant that recruited a rival's employees to obtain their skills is privileged; one that recruited them to cripple a competitor, with no intention of using them, may not be.

Financial interest, § 769. One with a financial interest in the third party's business may protect that interest by lawful means.

Responsibility for another's welfare, § 770. A parent, guardian, or fiduciary advising a person for whose welfare they are responsible.

Truthful information and honest advice, § 772. Providing truthful information, or honest advice within the scope of a request, is not improper interference — a defense of substantial practical importance. A consultant who advises a client that a vendor is underperforming, and the client terminates, is privileged. An attorney or accountant advising a client to breach where breach is the client's better economic course is generally privileged as well.

Protecting one's own legally protected interest, § 773. Asserting in good faith a legally protected interest, believing the claim to be valid — for example, telling a customer that the plaintiff's product infringes the defendant's patent. The privilege turns on good faith: bad-faith infringement assertions can support both an interference claim and, in patent cases, a Lanham Act or state-law claim, though federal patent law preempts state claims based on infringement assertions absent a showing of bad faith, a standard applied in Globetrotter Software, Inc. v. Elan Computer Group, Inc., 362 F.3d 1367 (Fed. Cir. 2004).

Noerr-Pennington. Petitioning the government — including filing lawsuits, lobbying, and administrative advocacy — is immune under Eastern Railroad Presidents Conference v. Noerr Motor Freight, Inc., 365 U.S. 127 (1961), and United Mine Workers v. Pennington, 381 U.S. 657 (1965). The sham exception, defined in Professional Real Estate Investors, Inc. v. Columbia Pictures Industries, Inc., 508 U.S. 49 (1993), requires that the petitioning be objectively baseless such that no reasonable litigant could realistically expect success, and that it conceal an attempt to interfere directly with a competitor's business relationships through the use of the governmental process as an anticompetitive weapon. Both prongs must be met, which makes the exception very difficult to establish.

The litigation privilege. Statements made in, or in serious contemplation of, judicial proceedings are absolutely privileged in most states, which defeats interference claims premised on pleadings, demand letters, and communications among counsel.

Consent and waiver, and the third party's independent decision — the strongest factual defense, established through the third party's own testimony that it made its decision for its own reasons.

Unfair competition and the adjacent claims

Common law unfair competition originally meant passing off — representing one's goods as another's. Modern state formulations vary widely: some states retain a narrow deception-based tort, others recognize a broad, flexible cause of action reaching any commercially unfair practice, and a few, notably California through its Unfair Competition Law, provide a statutory claim reaching any unlawful, unfair, or fraudulent business act with equitable remedies (restitution and injunction) but no damages.

Misappropriation. The International News Service v. Associated Press, 248 U.S. 215 (1918), "hot news" doctrine survives narrowly, sharply limited by copyright preemption. Courts recognizing it require the plaintiff to gather information at cost, the information to be time-sensitive, the defendant's use to constitute free-riding, direct competition, and a threat to the incentive to produce.

Breach of fiduciary duty by a departing employee. Employees owe a duty of loyalty during employment. What that permits and forbids is the recurring question:

  • Permitted while employed: forming an entity, obtaining financing, leasing space, and general preparations to compete.
  • Forbidden while employed: soliciting customers or coworkers for the new venture, diverting corporate opportunities, using the employer's resources for the competing venture, and disparaging the employer to customers.
  • Officers and directors owe heightened duties, including the corporate opportunity doctrine.

Aiding and abetting breach of fiduciary duty reaches the competitor that knowingly participates. Elements are typically a breach by the fiduciary, the defendant's knowledge of the breach, and substantial assistance. This is often the strongest claim against a hiring competitor, because it does not require an enforceable covenant — only knowledge that the employee was breaching a duty and participation in it.

Civil conspiracy requires an underlying tort; it is not independently actionable in most states. Its value is joint and several liability and the admissibility of co-conspirator statements.

Unjust enrichment and constructive trust provide restitutionary recovery where the defendant obtained a benefit it would be inequitable to retain, and are useful where damages are hard to prove but the defendant's gain is measurable.

Statutory overlays: the Defend Trade Secrets Act and state UTSA claims; the Lanham Act for false advertising and false designation of origin; state deceptive trade practices acts, several of which have fee-shifting; and the Computer Fraud and Abuse Act where information was taken from computer systems, narrowed substantially by Van Buren v. United States, 593 U.S. 374 (2021), which held that "exceeds authorized access" does not cover misuse of information the person was entitled to obtain.

The doctrines that eliminate claims

Three doctrines dispose of a large share of business tort claims before the merits.

Trade secret preemption. Most states' Uniform Trade Secrets Act enactments displace conflicting tort, restitutionary, and other law providing civil remedies for misappropriation of a trade secret. Courts split on scope: the majority approach preempts common law claims — unfair competition, unjust enrichment, conversion, and often interference — to the extent they are based on the same nucleus of facts as the misappropriation, whether or not the information qualifies as a trade secret. A minority preempts only claims involving information that actually is a trade secret.

The practical consequence is significant. A plaintiff that pleads misappropriation plus five common law claims arising from the same conduct will frequently lose the five. Claims that survive are those resting on independent facts — a breach of contract claim on a written agreement, a fiduciary duty claim based on conduct other than taking information, or interference based on customer solicitation rather than information use. Plead the factual bases separately and explicitly.

The economic loss rule bars tort claims for purely economic losses arising from a contractual relationship, confining the parties to their bargain. Its scope varies enormously by state, and most jurisdictions recognize exceptions for independent torts — fraud in the inducement in many states, breach of a duty independent of the contract, and claims by parties not in privity. Because interference claims by definition involve a non-party to the contract, the rule usually does not bar them; it matters more for fraud and negligent misrepresentation claims pleaded alongside.

Copyright and patent preemption. Section 301 of the Copyright Act preempts state law claims within the subject matter of copyright asserting rights equivalent to the exclusive rights — which reaches many misappropriation and unfair competition theories unless an extra element changes the nature of the claim. Federal patent law preempts state claims premised on infringement assertions absent bad faith.

Proof and damages

Proving causation is where these cases are usually won or lost, and the evidence is almost always in the third party's hands.

  • Third-party testimony is the central evidence. A customer or supplier who testifies that it left because of the defendant's misrepresentation makes the case; one who testifies that it left because the plaintiff's service declined ends it. Take these depositions early.
  • Contemporaneous documents — the third party's internal emails about why it switched, and the defendant's communications with it.
  • Timing — a departure or termination immediately following the defendant's contact is powerful circumstantial evidence.
  • Forensic evidence where information was taken: device images, USB connection logs, cloud sync records, and access logs. Preserve devices before anyone knows litigation is coming.

Damages theories:

  • Lost profits on the interfered-with contract or relationship, proven with reasonable certainty. New businesses face a higher bar in many states.
  • Lost business value where the interference destroyed a going concern.
  • Disgorgement of the defendant's profits, available under unjust enrichment and, in some states, as a measure for interference.
  • Reliance and consequential damages, subject to foreseeability.
  • Punitive damages, available in most states for intentional business torts on a showing of malice, oppression, or fraud — and the primary reason these torts are pleaded alongside a contract claim, since punitive damages are unavailable for breach of contract.
  • Attorney's fees only where a statute or contract provides them, which is why state deceptive trade practices act claims are often added.

Expert evidence is nearly always required for lost profits, and the analysis must isolate the interference from other causes — market conditions, the plaintiff's own performance, and ordinary attrition. A damages model that attributes the entire decline to the defendant invites exclusion.

Injunctive relief

Injunctions matter more than damages in most of these disputes, because the harm is ongoing.

The standard, Winter v. Natural Resources Defense Council, Inc., 555 U.S. 7 (2008): likelihood of success, irreparable harm, balance of equities, and the public interest. Irreparable harm is the contested element, because economic loss is ordinarily compensable. Plaintiffs establish it through loss of customer relationships and goodwill, loss of confidential information whose dissemination cannot be undone, and the threatened destruction of a business.

What can be enjoined: further use or disclosure of confidential information; solicitation of specifically identified customers; and, where a valid covenant exists, employment in a defined competitive capacity. Courts are far more willing to enjoin use of information and solicitation than to enjoin employment, and an order preventing someone from working is granted sparingly and narrowly.

Expedited discovery is frequently granted in these cases and is often the real objective of a preliminary injunction motion — device images, email, and third-party subpoenas obtained in weeks rather than months.

Bond. Rule 65(c) requires security. Where the injunction would shut down a competitor's line of business, the bond can be substantial, and courts have wide discretion in setting it.

Rule 65(d) requires the order to state its reasons, state its terms specifically, and describe in reasonable detail the acts restrained — without referring to the complaint. An order enjoining "unfair competition" is unenforceable; an order identifying the specific customers and the specific information is not.

Defending these claims

Attack the elements first.

  • Is the contract valid and enforceable? An unenforceable restrictive covenant defeats an interference claim built on it. Check the governing state's law, including the growing number of states that void non-competes outright or restrict them by wage threshold or occupation.
  • Was there a breach? Termination in accordance with the contract's terms is not a breach.
  • Is the relationship at-will? If so, argue the prospective standard and the independently wrongful requirement.
  • What is the independently wrongful act? Force the plaintiff to identify it specifically. "Unfair" and "improper" are conclusions, and Twombly and Iqbal require facts.
  • Knowledge — what did the defendant actually know, and when?
  • Causation — depose the third party and establish it made its own decision.

Then the privileges. Competition; truthful information; honest advice; protection of a legitimate financial interest; good-faith assertion of a legal right; Noerr-Pennington; the litigation privilege; and the agent-of-a-party rule where the defendant is an officer or affiliate.

Then the eliminating doctrines. Trade secret preemption of duplicative common law claims; the economic loss rule for tort claims arising from contract; copyright and patent preemption; and the statute of limitations, which for these torts is typically two to four years and may run from the interference rather than from discovery.

Counterclaims worth evaluating: abuse of process or malicious prosecution where the suit is baseless; the plaintiff's own interference or defamation, where it sent notice letters to customers accusing the defendant of wrongdoing; declaratory judgment that a restrictive covenant is unenforceable; and, where the plaintiff's conduct fits, an antitrust or unfair competition claim of its own.

A worked example

Ardenne Logistics contracts with Mercer Foods to provide warehousing under a three-year agreement with a 90-day termination-for-convenience clause. Eighteen months in, Mercer terminates on notice and moves to Northline Distribution.

Ardenne sues Northline for tortious interference.

Analysis, claim by claim.

Interference with contract. The contract permitted termination on 90 days' notice, and Mercer gave it. There was no breach, and the claim fails at the fourth element. Ardenne's better framing is interference with the prospective continuation of the relationship — which triggers the independently wrongful requirement.

Independently wrongful conduct. Discovery reveals three facts:

  1. Northline's proposal quoted a rate 8 percent below Ardenne's. Not wrongful — this is competition.
  2. Northline's sales director told Mercer's operations manager that Ardenne "was about to lose its warehouse lease and would be scrambling for space by summer." This was false, and Northline's director had no basis for it. Wrongful — a false statement of fact about a competitor, actionable as trade libel and as a Lanham Act violation if made in commercial promotion.
  3. Northline hired Ardenne's account manager for the Mercer relationship two months before the termination, and she forwarded Ardenne's rate structure and service level data to her personal email the week before she resigned. Wrongful — breach of the duty of loyalty and probable trade secret misappropriation, with Northline's knowing participation.

Claim selection. Ardenne pleads: interference with prospective economic advantage (independently wrongful conduct established by items 2 and 3); trade secret misappropriation under the DTSA and state UTSA; aiding and abetting breach of fiduciary duty against Northline; breach of the duty of loyalty against the former employee; and a Lanham Act § 43(a)(1)(B) claim on the false statement.

Preemption. Northline moves to dismiss the unfair competition and unjust enrichment claims as preempted by the state UTSA, and succeeds as to those, because they rested on the same facts as the misappropriation. The interference claim survives because it rests on the false statement as an independent basis — which is why Ardenne pleaded the two wrongful acts separately rather than as one undifferentiated allegation.

Relief. A preliminary injunction requiring return and deletion of the rate data, barring its use, and prohibiting repetition of the false statement. Damages measured by lost profits over the remaining term plus the reasonably probable renewal, reduced for the portion of the loss attributable to Northline's lawful price competition — a reduction the defense expert quantified and the court accepted.

Practical guidance

If you are losing business to a competitor:

  1. Preserve immediately — devices, email, access logs, and the departing employee's equipment. Do not reimage.
  2. Determine whether any enforceable agreement exists: non-compete, non-solicit, confidentiality, or assignment. Check enforceability under the governing state's current law before building a case on it.
  3. Interview the customer or supplier. What did they hear, from whom, and what drove the decision?
  4. Identify the independently wrongful act with specificity. If there is not one, there is probably not a case.
  5. Send a preservation and notice letter to the competitor — which establishes knowledge for every day afterward.
  6. Evaluate whether a Lanham Act or trade secret claim is stronger than the interference claim.
  7. Decide quickly whether to seek a preliminary injunction; delay undermines irreparable harm.

If you are hiring from a competitor:

  1. Ask every candidate, in writing, whether they are subject to any restrictive covenant, and obtain a copy.
  2. Instruct them in writing not to bring, retain, or use any confidential information, and to return everything before their last day.
  3. Do not ask for customer lists, pricing, or any document from the prior employer.
  4. Do not have the candidate solicit customers or coworkers before their departure.
  5. Where a covenant exists, obtain an enforceability opinion before the start date, and consider limiting the role's scope during the restricted period.
  6. Train recruiters and hiring managers on these rules, because the case will be built out of their emails.
  7. Keep the offer and onboarding file clean; it will be produced.

Frequently asked questions

A competitor hired our top salesperson. Can we sue? Not for hiring alone. You need an enforceable covenant, a trade secret, a breach of the duty of loyalty during employment, or some other independently wrongful act.

Our customer left mid-contract after a competitor called them. Is that interference? Only if the contract was breached and the competitor's conduct was improper. Offering a better price is privileged. Lying about you is not.

What if the non-compete is unenforceable? Then there was no breach to induce, and the interference claim built on it generally fails.

Can we sue the officer who caused the company to breach? Usually not, if the officer acted within the scope of authority in the company's interest. If the officer acted for personal benefit, some states permit the claim.

They told our customer we were about to go out of business. What claim is that? Trade libel and interference, and — if made in commercial promotion by a competitor — a Lanham Act claim, which is often the strongest of the three.

We pleaded six claims and lost four to preemption. Why? Most states' trade secret statutes displace common law claims resting on the same facts. Plead independent factual bases explicitly and separately.

Can we get an injunction stopping them from working there? Rarely, and only with a valid covenant. Courts far more readily enjoin use of information and solicitation of identified customers.

How long do we have? Typically two to four years depending on the state and the claim, and the clock may run from the interference rather than from discovery. Move quickly regardless — delay defeats injunctive relief.

Conclusion

Business tort litigation is a search for an independently wrongful act inside conduct that is otherwise privileged. Competition is lawful. Recruiting is lawful. Offering better terms is lawful. Telling a customer the truth about a competitor is lawful.

What is not lawful is lying, taking information, inducing a breach of a valid contract, or knowingly participating in someone else's breach of duty. Every strong interference case contains at least one of those, documented in an email that somebody sent without thinking.

Which cuts both ways. The company evaluating a claim should identify that act before filing, because without it the case is a privileged-competition defense waiting to happen. And the company hiring from a competitor should recognize that its own exposure is created almost entirely in the recruiting and onboarding process, by people who have never been told the rules.

Related claims by industry, and where they actually arise

The doctrine is uniform; the fact patterns are not. A few recurring settings are worth naming because the analysis shifts.

Professional services. Departing accountants, brokers, financial advisers, physicians, and lawyers take client relationships with them, and the governing rules are as much professional as legal. Bar rules in most states restrict non-compete agreements among lawyers outright and require that clients be notified of a departure and given a free choice of counsel. Broker-dealers operate under the industry's recruiting protocol conventions and FINRA arbitration. Physician practices face state statutes limiting or voiding medical non-competes and requiring patient notification and continuity of care. In each, an interference claim built on a covenant that professional rules will not enforce fails before it starts.

Staffing and recruiting. Placement fee disputes generate interference claims when a client hires a candidate directly to avoid the fee. The claim usually sounds in breach of the client agreement rather than in tort, and the tort claim against the candidate rarely survives — the candidate is not a party to the fee agreement and owes no duty.

Franchising. A franchisor's system-wide standards, territorial restrictions, and approved-supplier requirements produce interference claims from excluded suppliers and from franchisees. The competition privilege and the franchisor's legitimate interest in its system are strong defenses, and many disputes are governed by the franchise agreement's own dispute provisions and by state franchise relationship statutes.

Insurance and benefits brokerage. Book-of-business disputes, described in the opening example, are among the most common interference cases in the country. The outcome usually turns on whether the producer's agreement contained an enforceable non-solicit, whether the client list qualifies as a trade secret in that state, and whether the producer solicited before resigning.

Construction and supply chains. A general contractor that induces a subcontractor to abandon a competitor's project, or a supplier that cuts off a distributor at a competitor's request, produces claims where the privilege analysis is fact-intensive and where the underlying contracts frequently contain their own remedies.

Healthcare. Referral relationships, medical staff privileges, and payor contracting disputes generate interference claims that collide with peer review immunity under the Health Care Quality Improvement Act and with state peer review privileges, which can block both the claim and the discovery needed to prove it.

Technology channel disputes. Reseller terminations, competitive displacement of an incumbent integrator, and platform access decisions produce claims where the Trinko line on refusals to deal, the terms of the channel agreement, and the platform's own policies do most of the work.

In each setting the recurring lesson is the same: the enforceability of the underlying agreement, checked against the current law of the governing state, determines whether there is a case — and it is the question most often assumed rather than researched.

Related articles

This article is provided for general informational purposes and does not constitute legal advice. Business tort elements, privileges, preemption scope, and the availability of punitive damages vary substantially by state. Consult qualified counsel before filing or responding to an interference claim.