Published: 2026-09-10 — Ari
Advertising Law Basics Every Founder Should Know
Most founders learn advertising law the hard way — from a cease-and-desist letter, a competitor complaint, or an FTC inquiry. The rules aren't complicated once you understand the framework, and knowing them before you need them is significantly cheaper than learning them in response to an enforcement action.
The legal framework for advertising in the U.S.
U.S. advertising is regulated at the federal level primarily by the FTC under Section 5 of the FTC Act, which prohibits unfair or deceptive acts or practices in commerce. Specific industries have additional overlay: the FDA regulates health and food advertising claims, the CFPB oversees financial product advertising, and the FCC governs broadcast advertising.
State consumer protection laws add a parallel layer. Most states have statutes modeled on the FTC Act, and state attorneys general actively enforce them. For businesses operating nationally, compliance with both federal and the most restrictive state standards is the practical approach.
Truth in advertising: the core standard
The foundational rule: advertising must be truthful, not misleading, substantiated, and fair. Truthful means the claims are accurate. Not misleading means the overall impression is accurate, not just the literal words. Substantiated means you have evidence before you make the claim.
The 'overall impression' standard matters because technically true statements can be legally deceptive if the clear implication for a typical consumer is false. A claim that '9 out of 10 customers saw results' may be literally accurate but deceptive if the 'results' were trivial or the sample was selected to produce the statistic.
Comparative advertising: the rules
Comparing your product to a competitor's is legal and widely used — but it comes with elevated substantiation requirements. Every comparative claim must be substantiated, and the comparison must be fair and accurate. If you claim superiority, your evidence must show superiority on the specific attribute claimed.
Disparagement — making false statements of fact about a competitor's products — creates liability for commercial defamation (trade libel) independent of FTC compliance. Puffery ('we're the best') is generally protected; specific false factual claims are not.
Digital advertising: specific regulations to know
- Email: CAN-SPAM requires accurate headers, no deceptive subject lines, a physical address, and a working unsubscribe mechanism
- Text/SMS: TCPA requires prior express written consent for marketing texts; violations carry per-message statutory damages
- Online behavioral advertising: FTC guidelines require disclosure of data collection practices and choice mechanisms
- Dark patterns: deceptive design in subscription flows and online checkouts is actively enforced by the FTC
- Native advertising: content that looks editorial must be clearly labeled as advertising
Sweepstakes, contests, and promotions
Any promotion with a prize has specific legal requirements: official rules, no-purchase-necessary alternative, accurate prize descriptions, and state-specific requirements in New York and Florida for prize pools above certain thresholds. Running a promotion without official rules creates exposure for every entrant who doesn't receive what the promotion implied.
Social media platform rules for promotions add another compliance layer — each major platform prohibits certain types of promotions and requires specific disclosure language. Platform rules don't replace legal requirements; they stack on top of them.
Building legally sound marketing campaigns
A pre-flight compliance checklist for every campaign: Are all claims substantiated? Are material connections disclosed? Are the appropriate opt-in or consent mechanisms in place for the channels being used? Does any campaign element require regulatory notice (sweepstakes, financial products, health claims)?
For campaigns with significant budget or reach, a legal review before launch is worth the investment. The cost of compliance review is predictable; the cost of enforcement is not.