Lanham Act False Advertising Litigation
Publicidad falsa de un competidor: evaluamos la afirmación, las pruebas y el daño antes de demandar.
When a competitor's advertising misstates what its product does, or what yours does, the Lanham Act lets you sue for an injunction and money. The case turns on standing, on whether the claim is literally false or only misleading, and on the evidence that it changed what buyers did. We build that record before filing.
What Section 43(a)(1)(B) lets a business challenge
Section 43(a)(1)(B) of the Lanham Act, 15 U.S.C. § 1125(a)(1)(B), creates a federal claim against anyone who, in commercial advertising or promotion, misrepresents the nature, characteristics, qualities, or geographic origin of their own goods, services, or commercial activities, or those of another person. It is the federal statute a business uses when a competitor's advertising is taking its customers or damaging its reputation.
The claim covers two kinds of statements. The first is a false claim about the advertiser's own product: an unsupported "clinically proven" claim, a false performance number, a "Made in USA" label on imported goods. The second is a false statement about your product: a comparison chart that misstates your specifications, a sales deck that says your product is unsafe, a price comparison that is not true.
Unlike a trademark claim, a false advertising claim does not depend on owning a mark. It depends on proving that a specific statement is false or misleading, that it matters to buyers, and that it has injured, or is likely to injure, your sales or reputation. That makes the case a contest over evidence: the defendant's substantiation, your consumer research, and your sales data.
Susan J. Latham leads our false advertising litigation. She has litigated Lanham Act advertising claims for more than 20 years, both for companies challenging a competitor's claims and for companies whose claims are challenged.
Advertising we are often asked to review
- Efficacy or health claims with no competent support
- "Tests prove" or "clinically shown" claims that the cited study does not support
- Comparison charts and side-by-side demos that misstate a rival's product
- False country-of-origin statements, such as "Made in USA" or "imported from Italy"
- Sponsored posts, sales presentations, and trade-show materials making factual claims
- Spanish-language ads aimed at Miami and Latin American buyers that make claims the English ads do not
Who can sue: the two-part Lexmark test
In Lexmark International, Inc. v. Static Control Components, Inc. (2014), a unanimous Supreme Court replaced the circuits' competing standing tests with one inquiry built on two questions. Every plaintiff has to satisfy both.
An injury to a commercial interest in reputation or sales
The plaintiff must allege harm to its business, in the form of lost sales or damaged reputation. A consumer who was fooled by the ad and bought the wrong product falls outside the statute; the Court said such a consumer cannot invoke the Lanham Act. A business that lost customers because of the ad falls inside it.
Lexmark (2014)Injury flowing directly from the deception
The plaintiff must show economic or reputational injury that flows directly from the deception wrought by the defendant's advertising. That ordinarily happens when deceived buyers withhold trade from the plaintiff. Harm that reaches the plaintiff only through a long chain of other events is usually too remote.
Lexmark (2014)The Court rejected a rule limiting suits to direct competitors. Static Control made parts that others used to refurbish Lexmark cartridges, so it did not sell a competing cartridge. It could still sue, because Lexmark's statements disparaged its business directly and the resulting harm flowed from that deception.
In practice this means a component supplier, a distributor, or a company in an adjacent market can have standing when an ad targets it or its products. A direct competitor in a two-player market usually has the easiest causation story, because every sale the defendant wins with a false claim is plausibly a sale the plaintiff lost. In a crowded market, we build the causation record early: market share data, lost accounts, retailer feedback, and reviews that repeat the false claim.
What the defendant will argue
- Your losses come from price, quality, or other competitors, not the ad
- You are a consumer or a remote supplier, outside the zone of interests
- The ad never mentioned you, so any harm is indirect
We prepare for these arguments before filing, because a weak causation theory can end the case at the pleading stage. Defending a claim instead? See False Advertising Defense.
The five elements a plaintiff must prove in Florida federal court
The Eleventh Circuit, which covers Florida, Georgia, and Alabama, states the claim in five elements. It set them out in Johnson & Johnson Vision Care, Inc. v. 1-800 Contacts, Inc., 299 F.3d 1242 (11th Cir. 2002), and repeated them in Hickson Corp. v. Northern Crossarm Co., 357 F.3d 1256 (11th Cir. 2004).
| Element | What it means | Typical evidence |
|---|---|---|
| 1. False or misleading | The advertisement is literally false, or literally true but misleading in context. | The ad itself, the defendant's test data and substantiation file, independent testing, expert analysis |
| 2. Deception | The ad deceived, or had the capacity to deceive, consumers. Need not be shown for literally false claims; must be proved for misleading ones. | Consumer surveys, market research, expert testimony, customer communications |
| 3. Materiality | The deception had a material effect on purchasing decisions, meaning it was likely to influence buyers. | Proof the claim concerns an inherent quality of the product, survey questions on purchase drivers, the defendant's own marketing research |
| 4. Interstate commerce | The misrepresented goods or services affect interstate commerce. | Sales across state lines, online sales, national distribution |
| 5. Injury | The plaintiff has been, or is likely to be, injured by the false advertising. | Lost sales and accounts, price erosion, market share data, reputational harm |
Some Eleventh Circuit opinions phrase the claim through a six-part list drawn from the McCarthy treatise, which separately names "commercial advertising or promotion" and the misrepresentation of nature, qualities, or geographic origin. Suntree Technologies, Inc. v. Ecosense International, Inc. (11th Cir. 2012) used that formulation. The substance is the same, and the "commercial advertising or promotion" requirement is discussed below.
One point where Florida's federal courts differ from some others: in 1-800 Contacts, the Eleventh Circuit held that the plaintiff must prove materiality even when the ad is literally false. It declined to follow the Fifth Circuit's approach in Pizza Hut, which presumes an effect on consumers for literally false statements, and it acknowledged the circuit split. A plaintiff in Florida should plan to prove that the claim mattered to buyers in every case.
Literally false or misleading: the choice that shapes the case
How a claim is framed decides what evidence you need and how fast you can move. A literally false claim can support a preliminary injunction without a consumer survey. A misleading claim almost always needs one.
| Literally false | Literally true but misleading | |
|---|---|---|
| Definition | The claim is false as a factual matter, read in full context. | The claim may be true or ambiguous but implicitly conveys a false impression or is likely to deceive in context. |
| Proof of deception | Not required. The plaintiff need not present evidence that consumers were deceived. | Required, even at the preliminary injunction stage. |
| Consumer survey | Not needed to prove falsity, though often useful on materiality | Usually central. "Full-blown" surveys are not required at the preliminary stage, but some evidence of consumer reaction is. |
| Materiality | Must still be proved in the Eleventh Circuit | Must be proved |
| Ambiguity | Fatal. A claim open to more than one reasonable reading is not literally false. | Expected. The question is what consumers actually take away. |
| Typical speed | Can support an early injunction motion | Slower; the survey has to be designed, fielded, and analyzed |
◆ marks rows where the two theories call for different evidence.
"Tests prove" and "clinically shown"
When an ad cites tests or studies, the plaintiff does not have to prove the underlying claim false. It must prove only that the tests did not establish the proposition for which they were cited, or that they were not reliable enough to support it. The Eleventh Circuit applied this rule in 1-800 Contacts (2002) and in Osmose, Inc. v. Viance, LLC (2010), where it affirmed an injunction against safety claims the cited tests did not support.
11th Cir. 2002, 2010False by unavoidable message
Some courts treat an ad as literally false when its words or images, read in full context, unambiguously and necessarily imply a false message, even though no single sentence is false. The Second Circuit adopted this approach in Time Warner Cable, Inc. v. DIRECTV, Inc. (2007). The Eleventh Circuit has cautioned that the more a message depends on the consumer putting separate pieces together, the less likely a finding of literal falsity.
2d Cir. 2007Vague superiority is not actionable
"Bald assertions of superiority or general statements of opinion cannot form the basis of Lanham Act liability," as the Eleventh Circuit put it in Osmose. "The best coffee in Miami" is puffery. "Twice the caffeine of Brand X" is a measurable claim. An opinion that implies testable facts, such as a safety hazard, may be treated as a factual claim.
Osmose (2010)Consumer surveys and the rest of the proof
In Hickson, the Eleventh Circuit observed that the success of an implied falsity claim "usually turns on the persuasiveness of a consumer survey," and vacated a summary judgment because the trial court had overlooked the plaintiff's survey. A misleading-claim case is often won or lost on research design.
A survey in a false advertising case asks what message consumers take from the ad, and whether that message is false. A good one shows the ad as consumers actually encounter it, surveys the right buyers, uses a control version of the ad with the challenged message removed, and asks open questions before closed ones so the survey does not suggest the answer. The net difference between the test and control groups is the measure of deception the ad causes.
Materiality can be shown in more than one way. The Eleventh Circuit accepts proof that the defendant misrepresented an inherent quality or characteristic of the product. Survey questions on purchase drivers, the defendant's own marketing research showing why it chose the claim, and sales changes after the campaign launched all help.
The defendant's substantiation file is often the most important document in the case. An advertiser should have support for an objective claim before it runs. In discovery we ask for the test protocols, raw data, and internal emails about the claim. When the support was assembled after the challenge, or the tests measured something other than what the ad says, the establishment-claim rule does much of the work.
Evidence to gather before filing
- Every version of the ad, with dates, channels, and languages, captured in a forensically sound way
- Any test or study the ad cites, and independent testing of the claim
- Customer, distributor, and retailer messages that repeat the claim or mention switching
- Sales, pricing, and market share data before and after the campaign
- Reviews and social posts that show what buyers took from the ad
- A preservation demand to the advertiser (see Preservation Notices)
Is the statement "commercial advertising or promotion"?
Section 43(a)(1)(B) reaches only statements made in commercial advertising or promotion. In Suntree (2012), the Eleventh Circuit adopted the four-part test from Gordon & Breach Science Publishers v. American Institute of Physics (S.D.N.Y. 1994), calling it the most widely accepted test.
Speech that proposes a commercial transaction or promotes the speaker's products. Product reviews, news articles, and scientific papers may fall outside, depending on their purpose and how they are used.
This is the second Gordon & Breach prong as Suntree quoted it. Its status is debated after Lexmark, which rejected a direct-competitor requirement for standing. The Tenth Circuit kept the full four-part test as binding precedent in Strauss v. Angie's List (2020); other courts have dropped this prong. We plead around the issue where the facts allow.
In Suntree, a maintenance presentation given to train existing customers did not qualify.
A classic ad campaign is not required; informal promotion counts, and in a small industry a handful of presentations to key buyers can be enough. But the plaintiff has to prove the reach. In Suntree, the plaintiff offered no evidence of how many potential customers received the brochure, and the claim failed.
Practical point: track who received a sales deck, a brochure, or a trade-show handout. Dissemination evidence is easy to collect early and hard to rebuild later.
The lifecycle of a false advertising lawsuit
Many disputes end at the first or second step. When they do not, a federal false advertising case in Florida usually follows this path.
- Pre-suitReview and demandTest the claim, gather sales evidence, and decide between a demand letter, an NAD challenge, or suit.
- FilingComplaintIdentify each challenged statement, the theory of falsity, the channels, and the injury. Add Florida counts where they fit.
- EarlyTRO or preliminary injunctionStrongest for literally false claims and ongoing campaigns. A rebuttable presumption of irreparable harm applies.
- DiscoveryRule 26 and discoverySubstantiation files, test data, marketing research, ad spend, and sales by channel.
- ExpertsSurveys and economistsConsumer perception and materiality surveys; damages and profits analysis; rebuttal of the other side's survey.
- MotionsSummary judgmentFalsity, puffery, commercial advertising, and causation are common targets.
- TrialTrial, remedies, appealTrial on liability and money; the court decides the injunction and any fee award. Appeals go to the Eleventh Circuit.
Preliminary injunctions. A plaintiff must show a substantial likelihood of success on the merits, irreparable harm without an injunction, that its harm outweighs the harm to the defendant, and that the injunction would not disserve the public interest. Since the Trademark Modernization Act of 2020, 15 U.S.C. § 1116(a) gives a plaintiff that shows a likelihood of success on a § 1125(a) claim a rebuttable presumption of irreparable harm. Delay in seeking relief can rebut it, so speed matters once a campaign launches.
Courts also take care with the scope of the order. In Osmose, the Eleventh Circuit affirmed the core of the injunction but sent several provisions back to be limited to commercial advertising or promotion, because of First Amendment concerns. We draft proposed orders that target the false claims, not the defendant's speech in general.
Timing
The Lanham Act has no statute of limitations. Courts apply laches, and in Florida the Eleventh Circuit looks to the analogous four-year state period (AmBrit, Inc. v. Kraft, Inc., 1986). For injunctions, the more practical clock is the campaign itself: an ad that has run unchallenged for months weakens the irreparable harm presumption.
The National Advertising Division is a different tool, not a lawsuit
BBB National Programs' National Advertising Division (NAD) reviews challenges to national advertising claims under procedures last revised effective March 16, 2026. It is industry self-regulation: faster and cheaper than court, but it awards no money and cannot order anyone to do anything.
| Federal court (Lanham Act) | NAD challenge | |
|---|---|---|
| Who decides | Federal judge and jury | NAD attorneys; appeal to a National Advertising Review Board (NARB) panel |
| Standing | Lexmark test; commercial injury required | Competitors and others can file; no injury showing |
| Burden | On the plaintiff to prove falsity | Focus is on whether the advertiser's substantiation supports the claim |
| Speed | Months to years; TRO in days | Advertiser responds within 15 business days on the standard track; Fast-Track SWIFT decisions within 20 business days |
| Outcome | Injunction, profits, damages, costs, fees in exceptional cases | Recommendation to modify or discontinue the claim; no damages |
| If ignored | Contempt of court | NAD may refer the matter to a government agency, such as the FTC |
| Pending litigation | Court proceeds | NAD may decline or administratively close a case on claims in pending litigation |
◆ marks rows where the forums differ in kind, not only degree.
Choosing NAD first does not waive a later Lanham Act suit, but NAD generally will not hear claims already in litigation, and decisions are published. We help clients decide which forum fits the claim and the business goal.
What a court can order in a false advertising case
Remedies come from 15 U.S.C. §§ 1116 and 1117(a), which apply to § 1125(a) violations. Money relief is "subject to the principles of equity" and must compensate, not punish. The full math is on our Damages Evaluations page.
Injunction
An order stopping the false claim, sometimes with a recall of materials or required changes to labels and listings. This is often the main goal.
15 U.S.C. § 1116(a)Corrective advertising
Courts can award the cost of advertising needed to correct the false impression, but only with evidence of what it would cost and why it is needed. The Fifth Circuit vacated an unsupported corrective-advertising award in Illinois Tool Works, Inc. v. Rust-Oleum Corp. (2020), calling it a windfall.
§ 1117(a), damagesDefendant's profits
Profits must be tied to the false advertising, not just to the defendant's overall sales. Willfulness is not a precondition (Romag Fasteners, Inc. v. Fossil, Inc., 2020), though intent matters in the court's equitable judgment.
15 U.S.C. § 1117(a)Plaintiff's damages
Lost sales, price erosion, and reputational harm, proved with evidence rather than speculation. The court may enter judgment for up to three times actual damages.
15 U.S.C. § 1117(a)Costs and attorney's fees
Fees are available in exceptional cases. The Eleventh Circuit applies the Octane Fitness totality-of-the-circumstances standard to Lanham Act fee requests (Tobinick v. Novella, 884 F.3d 1110 (11th Cir. 2018)). The rule runs both ways: a defendant that defeats a weak claim can seek its fees too.
15 U.S.C. § 1117(a)Florida claims that travel with a Lanham Act advertising case
Florida adds two statutes that are often pleaded alongside a federal false advertising count. Each has different elements and a different fee rule.
Deceptive or unfair acts in trade or commerce. Declaratory and injunctive relief for anyone aggrieved; actual damages for a person who suffered a loss. The Eleventh Circuit applies the Lanham Act analysis to FDUTPA claims built on the same conduct (Suntree, 2012). See FDUTPA Litigation.
The prevailing party may recover attorney's fees, and that can be the defendant. A FDUTPA count added by reflex can create fee exposure for the plaintiff.
Prohibits misleading advertisements made before the general public of Florida. A person prevailing in a civil action recovers costs, including reasonable attorney's fees, and may be awarded punitive damages in addition to actual damages. Courts generally require the plaintiff to show its own reliance, which many competitors cannot.
An overview of all Florida competition claims is on Florida Unfair Competition. If the advertising also misuses your mark or suggests a false affiliation, see False Designation of Origin Claims and Federal Unfair Competition Claims.
Five mistakes that weaken a false advertising case
Calling a misleading claim "literally false"
Plaintiffs often plead literal falsity to avoid the cost of a survey. If the court finds the ad ambiguous, the literal falsity theory fails and there may be no consumer evidence to fall back on.
1-800 Contacts (2002)Plead both theories where the facts support them, and start survey work early.
Assuming materiality
In the Eleventh Circuit, materiality must be proved even for a literally false claim. A trivial falsehood that does not affect buying decisions does not support liability.
MaterialityTie the claim to an inherent quality or a known purchase driver.
No proof of reach
A brochure or presentation is not "advertising or promotion" unless the plaintiff can show it reached enough of the relevant buyers.
Suntree (2012)Collect distribution lists, ad spend, impressions, and trade-show attendance.
Waiting to seek an injunction
The statutory presumption of irreparable harm is rebuttable. Months of delay while a campaign runs invite the argument that the harm is not urgent.
15 U.S.C. § 1116(a)Decide on the injunction strategy in the first weeks.
Running claims of your own you cannot support
A defendant's first move is often a counterclaim against the plaintiff's advertising. Unsupported claims in your own marketing become the other side's leverage.
CounterclaimsAudit your own comparable claims before filing.
How this claim fits a lawsuit
Claims usually pleaded together
- Federal Unfair Competition ClaimsWhen the ad also passes off goods or claims a false connection with your brand
- False Designation of Origin ClaimsWhen the campaign uses your mark or suggests sponsorship or approval
- FDUTPA LitigationFlorida deceptive-practices count on the same conduct; two-way fee risk
- Florida Unfair CompetitionOverview of § 817.41 misleading advertising and other Florida claims
- Federal Trademark Infringement LitigationWhen the ad uses your registered mark in a way likely to confuse buyers
Remedies at a glance
| Injunction | Stop the claim; rebuttable presumption of irreparable harm (§ 1116(a)) |
|---|---|
| Corrective advertising | Cost to correct the false impression, with proof of need and cost |
| Defendant's profits | Profits attributable to the false advertising (§ 1117(a)) |
| Damages | Lost sales and reputational harm, up to three times actual damages |
| Costs and fees | Costs; attorney's fees in exceptional cases |
What a claim may be worth: see Damages Evaluations.
We bring these claims in the U.S. District Courts for the Southern, Middle, and Northern Districts of Florida, and in Florida circuit courts. Misleading-advertising and FDUTPA claims can be heard with the federal count under supplemental jurisdiction. Out-of-state firms with a Florida case: see Local Counsel Representation and MiamiTrademarkLocalCounsel.com.
This page is written for the party bringing the claim. If you have been sued or threatened, see False Advertising Defense, or upload the complaint and note your response deadline.
Frequently asked questions
Do I have to be a direct competitor to sue for false advertising?
No. Under Lexmark (2014), the plaintiff must show an injury to a commercial interest in reputation or sales that flows directly from the deception. Competitors usually meet that test most easily, but non-competitors whose business the ad targets can qualify. Consumers cannot sue under the Lanham Act.
Do I need a consumer survey?
If the claim is literally false, you do not need a survey to prove deception, although survey evidence can still help prove materiality. If the claim is literally true but misleading, you need evidence of what consumers took away, and in the Eleventh Circuit that is usually a survey. At the preliminary injunction stage, a full-blown survey is not required, but some evidence of consumer reaction is.
What is an establishment claim?
An ad that cites tests or studies, such as "clinically proven" or "tests show." The plaintiff can win by proving the tests did not establish the claim, or were not reliable enough to support it, without proving the underlying proposition false.
Is "the best" or "number one" actionable?
Usually not on its own. Vague superiority claims are puffery. A claim becomes actionable when it is specific and measurable, such as "number one in sales in Florida in 2025" or "lasts twice as long as Brand X," because it can be proved true or false.
How long do I have to file?
The Lanham Act has no statute of limitations. Federal courts in Florida apply laches and look to Florida's four-year period as a guide. If you want an injunction, waiting is risky well before that, because delay can rebut the presumption of irreparable harm. FDUTPA claims have a four-year limit under Fla. Stat. § 95.11(3)(e).
Should I go to the NAD instead of court?
It depends on the goal. The NAD is faster and cheaper and focuses on whether the advertiser can substantiate its claim, but it cannot award damages or issue an injunction, and it generally will not hear claims already in litigation. Court is the forum when you need an enforceable order or money.
Can I recover my attorney's fees?
Only in an exceptional case under 15 U.S.C. § 1117(a), judged on the totality of the circumstances. Florida's FDUTPA and § 817.41 have their own fee provisions; under FDUTPA, fees can go to a prevailing defendant as well.
The ad runs in Spanish on Miami radio and social media. Does the Lanham Act still apply?
Yes. The statute does not depend on the language of the ad. We review Spanish-language advertising directly, since our attorneys work in English and Spanish, and we use certified translations for the court record.
A competitor says our ads are false. Where do we look?
This page is for companies bringing claims. If you received a demand or a complaint, see False Advertising Defense or Responding to a Demand Letter.
Discuss your case
Send copies or links of the challenged ads (with dates and channels), any study the ad cites, and a short note on the sales or accounts affected. If you have been sued over your own advertising, upload the complaint and note the response deadline.
- Review of the challenged claims and the advertiser's likely substantiation
- Standing and causation analysis under Lexmark
- Survey and expert planning with outside researchers
- Injunction motions, NAD challenges, and Florida companion claims
Prefer to talk first? Call or email, or message us on WhatsApp. Atendemos en español.
- 15 U.S.C. § 1125 (Cornell LII)
- 15 U.S.C. § 1116 (Cornell LII)
- 15 U.S.C. § 1117 (Cornell LII)
- Lexmark International, Inc. v. Static Control Components, Inc. (U.S. 2014)
- Johnson & Johnson Vision Care, Inc. v. 1-800 Contacts, Inc., 299 F.3d 1242 (11th Cir. 2002)
- Hickson Corp. v. Northern Crossarm Co., 357 F.3d 1256 (11th Cir. 2004)
- Osmose, Inc. v. Viance, LLC (11th Cir. 2010)
- Suntree Technologies, Inc. v. Ecosense International, Inc. (11th Cir. 2012)
- Commercial advertising or promotion after Lexmark: Strauss v. Angie's List (10th Cir. 2020) (Tushnet)
- Time Warner Cable v. DIRECTV (2d Cir. 2007), summary (CCBJ)
- Illinois Tool Works, Inc. v. Rust-Oleum Corp. (5th Cir. 2020)
- NAD/NARB Procedures, revised effective March 16, 2026 (BBB National Programs)
- Martin v. E.C. Publications, Inc. (11th Cir. 2021) (laches; AmBrit; Florida four-year period)
- Fla. Stat. § 817.41 (2026)
General information, not legal advice for your situation. Statutes, rules, and fees as of October 2026. Last reviewed October 28, 2026.