Trade secret misappropriation has three elements, and a claim fails if any one is missing: the information must qualify as a trade secret, the defendant must have acquired it by improper means or disclosed or used it without consent, and the defendant must have known or had reason to know the secret came from improper means or a duty of confidence.
That structure is materially the same under the federal Defend Trade Secrets Act, which defines “trade secret” at 18 U.S.C. § 1839(3) and “misappropriation” at § 1839(5), and the Uniform Trade Secrets Act, which every state except New York and North Carolina has adopted in some form. New York still runs on common law drawn from the Restatement (First) of Torts § 757, and North Carolina has its own Trade Secrets Protection Act rather than a UTSA enactment. The vocabulary shifts slightly across those sources, but the analytical spine does not.
This is the threshold defendants attack first, and it is where a surprising share of claims die before anyone reaches the theft. Two requirements do the work.
The information must derive independent economic value from not being generally known to people who could exploit it. Value comes from the secrecy itself, not from the information being useful. A customer list assembled from public directories fails here, because a competitor could rebuild it with effort but no wrongdoing.
The owner must also have taken reasonable measures to keep it secret. Reasonable is a relative standard, not a perfect one, but it is a real one. Courts look for access controls, confidentiality agreements, exit interviews, marked documents, and segregation of sensitive data. A company that emailed its formula to a distributor with no restriction, or let every employee browse the whole file server, has a problem no amount of bad conduct by the defendant will cure. Secrecy is a precondition, not a consequence of the lawsuit.
The statute defines misappropriation in two distinct branches, and they are not the same claim.
Acquisition is misappropriation on its own. Someone who obtains a trade secret through improper means is liable at the moment of acquisition, whether or not they ever use it or tell anyone. The hacker who exfiltrates a database and leaves it untouched has misappropriated it.
Disclosure or use without consent is the second branch, and it reaches people who acquired the secret perfectly lawfully. A licensee who received the information under an NDA and then exploits it beyond the license did nothing improper to get it. The wrong is what came after.
Most real disputes involve both. A departing engineer who copies a repository to a personal drive commits improper acquisition, then commits improper use when the new employer’s product ships with the code inside it.
18 U.S.C. § 1839(6) lists theft, bribery, misrepresentation, breach or inducement of a breach of a duty to maintain secrecy, and espionage through electronic or other means. The list is illustrative rather than exhaustive, which matters more than it sounds.
The canonical illustration is E.I. duPont deNemours & Co. v. Christopher, 431 F.2d 1012 (5th Cir. 1970). DuPont was building a plant in Beaumont, Texas to produce methanol by an unpatented secret process. Rolfe and Gary Christopher, commercial photographers, were hired by an unknown third party to fly over the site and photograph the exposed process from the air. The flight broke no law, the airspace was open, and no fence was climbed. The Fifth Circuit held it was improper means anyway, reasoning that improper means includes conduct falling below “generally accepted standards of commercial morality,” and that requiring DuPont to put a roof over the unfinished plant “would impose an enormous expense to prevent nothing more than a school boy’s trick.”
The lesson generalizes. Lawful is not the same as proper. Pretexting a call to an engineer, scraping a partner portal you were credentialed into for a different purpose, or hiring away a competitor’s team to harvest what is in their heads can all qualify, even where no statute is violated.
Two acquisition routes are complete defenses, not partial ones, and § 1839(6)(B) writes both into the statute: improper means “does not include reverse engineering, independent derivation, or any other lawful means of acquisition.”
Reverse engineering a product you lawfully obtained is protected. The Supreme Court said so in Kewanee Oil Co. v. Bicron Corp., 416 U.S. 470 (1974), holding that trade secret law “does not offer protection against discovery by fair and honest means, such as by independent invention, accidental disclosure, or by so-called reverse engineering.” That the process took the defendant years and millions of dollars is irrelevant to liability. Two caveats: the starting article must have been acquired legitimately, since teardown of a stolen unit does not launder the theft, and a contract or license may separately bar reverse engineering as a matter of contract law rather than trade secret law.
Independent derivation is likewise a full answer. If the defendant developed the same thing without touching your secret, you have no claim no matter how identical the result. This is the structural trade-off of choosing secrecy over a patent: a patent excludes the world including independent inventors, while a trade secret only reaches wrongful conduct. Proving genuine independence is an evidentiary fight, which is why disciplined engineering organizations keep dated development records and use clean-room procedures.
Liability tracks what the defendant knew or had reason to know. Constructive knowledge counts, so willful blindness is not a shelter.
This is what extends the claim past the person who did the taking. A competitor who hires an engineer and receives a folder of documents plainly stamped confidential has reason to know their provenance. That knowledge makes their subsequent use actionable even though they never touched the original server. Downstream recipients occupy a spectrum: someone who acquires a secret innocently, in good faith and for value, and only later learns of the taint is treated more leniently, and courts often limit relief to prospective use rather than damages for what came before.
The breach-of-duty branch presumes a duty exists. It need not be written. An express duty comes from an NDA, an employment agreement, or a license. An implied duty arises from the circumstances: employees owe one by virtue of the employment relationship, and a duty attaches where information is disclosed in confidence for a limited purpose, such as a vendor negotiation or investor diligence, and both sides understood as much.
An NDA is still worth having, for two reasons that have nothing to do with creating the duty. It documents that a duty existed, removing a fight from the case. And its existence is evidence of the reasonable secrecy measures element one demands.
A related doctrine, inevitable disclosure, argues that a departing employee cannot help but use what they know, so use should be presumed. The Seventh Circuit applied it in PepsiCo, Inc. v. Redmond, 54 F.3d 1262 (7th Cir. 1995). California rejects it outright: Whyte v. Schlage Lock Co., 101 Cal. App. 4th 1443 (2002), held the doctrine contrary to state policy because it manufactures an after-the-fact covenant not to compete. Whether the doctrine is available is a live question of forum.
What are the elements of trade secret misappropriation? Three things must be proven. First, the information qualifies as a trade secret, meaning it derives independent economic value from not being generally known and the owner took reasonable measures to keep it secret. Second, the defendant either acquired it by improper means or disclosed or used it without consent. Third, the defendant knew or had reason to know the secret was acquired improperly or under a duty of confidence. Under the federal Defend Trade Secrets Act, the secret must also relate to a product or service used in interstate or foreign commerce.
What counts as improper means? 18 U.S.C. § 1839(6) lists theft, bribery, misrepresentation, breach or inducement of a breach of a duty to maintain secrecy, and espionage through electronic or other means. The list is illustrative, not exhaustive. Conduct can be improper even when it breaks no other law: in E.I. duPont deNemours v. Christopher, photographers hired by a competitor flew over a plant under construction and shot the exposed process from public airspace, which was improper means despite being perfectly legal aviation.
Is reverse engineering trade secret misappropriation? No. Reverse engineering and independent derivation are expressly carved out of improper means by 18 U.S.C. § 1839(6)(B), and the Supreme Court confirmed in Kewanee Oil v. Bicron that trade secret law offers no protection against discovery by fair and honest means. Both are complete defenses, not mitigating factors. The caveat is that the starting product must have been obtained lawfully, and a contract or license may separately restrict teardown.
Do you need a signed NDA to sue for misappropriation? No. A duty of confidence can be implied from the circumstances even with no signed agreement, and employees owe one by virtue of the employment relationship itself. An NDA helps by documenting the duty and evidencing the reasonable secrecy measures the first element requires, but its absence is not fatal. Improper acquisition, such as hacking a server, is actionable with no relationship between the parties at all.
Going further: Trade Secret Stolen? What to Do First .
This page is general legal information, not legal advice, and it does not create an attorney-client relationship.
The Eighth Circuit held that trade secret misappropriation can be pled on information and belief when the proof sits in the defendant's sole control.
The Ninth Circuit reversed an injunction over published tubular lock key codes, holding reverse engineering by lawful owners is not improper means.
The Eleventh Circuit held that scraping a public database with a bot can be improper means of acquiring a trade secret, even when any single piece of the data is free to view.
How a Massachusetts jury found a competing insulin-patch maker liable for misappropriating Omnipod design secrets, and why the court then cut the award by nearly 90 percent.
A Northern District of New York court denied a trade-secret injunction where a former employee's new employer plausibly reverse-engineered publicly available parts, and the plaintiff could not prove its specifications were secret or improperly taken.
The California Supreme Court held that under the UTSA, continued misuse of a trade secret after the initial theft is one continuing claim accruing at the first misappropriation, not a series of fresh claims.
The Ninth Circuit vacated the wholesale transfer of the billion-dollar Bratz brand to Mattel, holding that an employee-invention clause's reach over mere "ideas" was ambiguous and the equitable remedy grossly overbroad.
The Seventh Circuit held that a would-be buyer who received a target's secret designs during acquisition negotiations and then built a competing product had breached a confidential relationship the law implied from the dealings themselves.
A 1970 Fifth Circuit decision held that aerial photography of a plant under construction was an improper means of acquiring a trade secret, even though the photographers committed no trespass, breached no confidence, and were never shown to have broken any other law.
