Wisconsin Trade Secret Laws: UTSA, Remedies & Deadlines

Wisconsin's trade secret statute, Wis. Stat. § 134.90 (enacted 1985), follows the Uniform Trade Secrets Act framework and places its substantive civil provisions in numbered subsections within one section, with lettered paragraphs beneath them. The civil limitations period is three years from discovery.

This guide is part of our Trade Secret Laws by State series.

Information last verified on 2026-06-25. This article presents general legal information, not legal advice. This guide covers civil trade-secret protection in Wisconsin under Wis. Stat. § 134.90 and the federal DTSA; for other jurisdictions see the full Trade Secret Laws by State index.

Does Wisconsin have a trade secret law?

Yes. Wisconsin enacted Wis. Stat. § 134.90, commonly called the Wisconsin Uniform Trade Secrets Act, in 1985 (Wisconsin Legislature, docs.legis.wisconsin.gov). The statute adopts the Uniform Trade Secrets Act framework published by the Uniform Law Commission and establishes a civil cause of action for misappropriation of trade secrets. Wisconsin's codification is unusual: rather than spreading the law across separately numbered sections as most states do, the substantive civil provisions appear as numbered subsections with lettered paragraphs within a single statute, from § 134.90(1) through § 134.90(7). Practitioners must look to subsections rather than separate code sections when citing specific rules. Wisconsin's law displaces conflicting tort claims based on the same misappropriation (Wis. Stat. § 134.90(6)), but preserves contract remedies, criminal liability, and other civil claims not grounded in misappropriation. The federal Defend Trade Secrets Act (DTSA), 18 U.S.C. §§ 1836-1839 (2016), also applies when a Wisconsin trade secret relates to a product or service used in or intended for use in interstate or foreign commerce. Federal law does not preempt state trade secret law (18 U.S.C. § 1838), so Wisconsin and DTSA claims may proceed together in a single action.

What counts as a trade secret and misappropriation in Wisconsin?

Under Wis. Stat. § 134.90(1)(c), a trade secret is information, including a formula, pattern, compilation, program, device, method, technique, or process, that:

1. Derives independent economic value, actual or potential, from not being generally known to and not being readily ascertainable by proper means by other persons who can obtain economic value from its disclosure or use; and
2. Is the subject of efforts that are reasonable under the circumstances to maintain its secrecy.

Both elements must be present. Courts examine whether the owner took concrete protective steps: non-disclosure agreements, access restrictions, password controls, and written confidentiality policies all support the reasonable-measures prong. A business that circulates a proprietary formula within the organization with no restrictions will struggle to satisfy this element even if the underlying information is genuinely valuable.

Misappropriation under Wis. Stat. § 134.90(2) includes acquisition of another's trade secret by means the person knows or has reason to know are improper. It also includes disclosure or use without express or implied consent by a person who used improper means to acquire it; separate branches cover specified knowledge, confidentiality-duty and accident-or-mistake circumstances.

Wis. Stat. § 134.90(1)(a) gives a nonexclusive list of improper means, including theft, bribery, misrepresentation, espionage and breach or inducement of a confidentiality duty. It does not expressly identify reverse engineering or independent development as safe harbors. The distinction between proper and improper means supports examining how information was obtained, including whether confidentiality or use restrictions apply.

Remedies and the limitations period in Wisconsin

Limitations period: Wisconsin law gives three years, running from the date the misappropriation was discovered or, by the exercise of reasonable diligence, should have been discovered. The period comes from Wis. Stat. § 893.51(2) in the general limitations chapter; § 134.90 itself contains no limitations subsection. This is consistent with the UTSA model. Continuing misappropriation is treated as a single claim, with the period running from the first act the owner discovered or should have discovered.

Injunctive relief: Courts may enjoin actual or threatened misappropriation. Under Wis. Stat. § 134.90(3)(b), an injunction may condition future use on a reasonable royalty in exceptional circumstances, including a material and prejudicial change of position before knowledge or reason to know of misappropriation that makes a prohibitive injunction inequitable. The royalty period cannot exceed the period for which use could have been prohibited.

Damages: Wis. Stat. § 134.90(4)(a) permits actual-loss damages and unjust enrichment not already included in actual loss. Damages may be measured exclusively by a reasonable royalty if the claimant cannot prove, by another method, damages exceeding that royalty.

Exemplary damages: For willful and malicious misappropriation, the court may award additional punitive damages up to twice the award under Wis. Stat. § 134.90(4)(a).

Attorney fees: The court may award reasonable attorney fees to the prevailing party if a misappropriation claim is made in bad faith, a motion to terminate an injunction is made or resisted in bad faith, or misappropriation is willful and deliberate (Wis. Stat. § 134.90(4)(c)).

Wisconsin also criminalizes specified unauthorized acts involving property representing a trade secret when accompanied by intent to deprive the owner of control or appropriate its use. Wis. Stat. § 943.205(1), (3) makes a violation a Class I felony; § 134.90(6)(b)3 preserves criminal remedies.

How the federal DTSA applies in Wisconsin

The DTSA (18 U.S.C. §§ 1836-1839) took effect May 11, 2016, and provides a federal civil remedy when a Wisconsin trade secret relates to a product or service used in or intended for use in interstate or foreign commerce. Because most commercial activity in Wisconsin involves interstate commerce, DTSA claims are available in the vast majority of Wisconsin trade secret disputes.

Key DTSA features that operate alongside Wisconsin state law:

• Limitations period: Both the DTSA and Wisconsin's trade secret statute provide three-year limitations periods from discovery. The windows run concurrently, so there is no gap between the state and federal periods.
• Ex parte seizure: The DTSA authorizes courts to order the seizure of property to prevent propagation of a trade secret without advance notice to the defendant in extraordinary circumstances (18 U.S.C. § 1836(b)(2)). Wisconsin's statute does not include an equivalent provision.
• Comparable remedies: DTSA remedies, including injunctions, damages, up to 2x exemplary for willful and malicious misappropriation, and attorney fees, parallel Wisconsin's state remedies and apply under federal standards and procedures.
• Whistleblower immunity and notice: Under 18 U.S.C. § 1833(b), an individual may disclose a trade secret in confidence to a government official or attorney to report a suspected legal violation without civil or criminal liability. Employers must include written notice of this immunity in any confidentiality or employment agreement signed or updated after May 11, 2016. An employer who omits this notice cannot recover exemplary damages or attorney fees in a DTSA action against the person covered by that agreement.

Wisconsin employers should audit all post-2016 confidentiality agreements, NDAs, and employment contracts to confirm DTSA-compliant whistleblower language is present in each document.

This is general legal information, not legal advice. It describes Wisconsin trade-secret law under Wis. Stat. § 134.90 and the federal DTSA as of 2026-06-25 and does not address your specific facts. Trade-secret disputes are highly fact-specific and deadlines are strict. Consult an attorney licensed in Wisconsin before acting.

Related articles

• Trade Secret Laws by State
• West Virginia Trade Secret Laws
• Wyoming Trade Secret Laws
• Is AI-generated code copyright infringement?

Last updated: 2026-06-25.

Frequently Asked Questions

What is Wisconsin's limitations period for a trade secret claim?

Three years from the date the misappropriation was discovered or, by the exercise of reasonable diligence, should have been discovered. The federal DTSA provides the same three-year period from discovery (18 U.S.C. § 1836(d)), so both windows align and run concurrently.

What types of information qualify as trade secrets in Wisconsin?

Under Wis. Stat. § 134.90(1)(c), any formula, pattern, compilation, program, device, method, technique, or process can qualify if it derives independent economic value from not being generally known or readily ascertainable and the owner takes reasonable steps to protect it. Customer lists, pricing strategies, manufacturing processes, source code, and proprietary algorithms are common candidates, each subject to the two-part test.

Can a Wisconsin employer sue a former employee for misappropriating trade secrets?

Yes. If a former employee discloses or uses protectable Wisconsin trade secrets in breach of a confidentiality agreement or other duty of confidentiality, the employer may bring a civil claim under Wis. Stat. § 134.90. General skills, experience, and industry knowledge an employee develops during employment are not trade secrets and cannot be restricted. The distinction between protected information and general know-how is often disputed and depends on specific facts.

Is reverse engineering a trade secret legal in Wisconsin?

Wis. Stat. § 134.90(1)(a) gives a nonexclusive list of improper means, including theft, bribery, misrepresentation, espionage and breach or inducement of a confidentiality duty. It does not expressly identify reverse engineering or independent development as safe harbors. The distinction between proper and improper means supports examining how information was obtained, including whether confidentiality or use restrictions apply.

What does the DTSA whistleblower-immunity notice require for Wisconsin employers?

Under 18 U.S.C. § 1833(b)(3), any Wisconsin employer who enters into or updates a confidentiality agreement, NDA, or employment agreement after May 11, 2016 must notify the individual that they may disclose a trade secret in confidence to a government official or attorney to report a suspected legal violation without civil or criminal liability. Omitting this notice forfeits the employer's right to seek exemplary damages and attorney fees in a DTSA action against that individual.