A handful of companies now stand between most Missourians and the digital economy. One firm fields the vast majority of online searches. Two firms control the app stores on nearly every smartphone in St. Louis. A single marketplace sets the terms for millions of sellers, including thousands of Missouri small businesses. When a company with that kind of power raises prices, locks out rivals, or tilts its own platform in its favor, antitrust law is the tool that pushes back.

Most Missouri readers experience these fights as Washington news. That misses half the picture. Missouri has its own antitrust statute, its own attorney general, and its own courts. Federal law also gives injured consumers and businesses a private right to sue, with damages tripled for a winning plaintiff. This guide explains what the law actually forbids, which cases are already reshaping the tech sector, and what practical steps you can take if a dominant platform has harmed you.

Missouri has its own antitrust law, and it runs alongside federal law

Three federal statutes do most of the work. Section 1 of the Sherman Act, 15 U.S.C. § 1, bans contracts and conspiracies that restrain trade — think competitors agreeing on prices. Section 2, 15 U.S.C. § 2, targets a single firm that monopolizes or attempts to monopolize a market. Section 7 of the Clayton Act, 15 U.S.C. § 18, lets the government block mergers that may substantially lessen competition. The U.S. House Office of the Law Revision Counsel publishes the current text of these provisions.

Missouri adds a parallel layer. The Missouri Antitrust Law, RSMo §§ 416.011 through 416.161, declares restraints of trade unlawful under RSMo § 416.031 and directs the Missouri Attorney General to prosecute violations under RSMo § 416.051, which carries penalties. The full chapter appears on the Missouri Revisor of Statutes. One feature matters more than any other for readers: RSMo § 416.141 tells Missouri courts to construe the state act in harmony with comparable federal law. Decades of federal antitrust precedent therefore guide Missouri cases directly.

A third statute often fits tech-sector consumer harm even better. The Missouri Merchandising Practices Act, RSMo § 407.020, forbids deception and unfair practices in trade or commerce, and RSMo § 407.025 gives injured consumers a private right to sue. When a platform's conduct looks more like consumer deception than classic monopolization, this act may be the practical vehicle.

Being a monopoly is legal; monopolizing is not

Antitrust law does not punish success. A company that dominates a market because it built a better product, outworked its rivals, or simply got there first has broken no law. Courts repeat this point constantly, and it comes straight from United States v. Grinnell Corp., 384 U.S. 563 (1966), the Supreme Court's framework monopolization case.

A monopolization claim under Section 2 needs two elements. First, the firm must hold monopoly power in a properly defined market — real power over price or output, not just a large size. Second, the firm must have acquired or kept that power through exclusionary conduct rather than through honest competition. The second element is where most tech fights happen.

What counts as exclusionary? Paying distributors billions for exclusive default placement so rivals never reach users. Designing a platform so the owner's own products always rank above competitors' better products, in a way that destroys rivals rather than serves customers. Pricing below cost to bleed a competitor dry, then raising prices once the competitor folds. Conditioning access to a must-have product on buying a second product. Each of these has featured in recent tech litigation, and each goes beyond hard-nosed competition into conduct that harms the competitive process itself.

Attempted monopolization has its own test. Under Spectrum Sport, Inc. v. McQuillan, 506 U.S. 447 (1993), the plaintiff must show exclusionary conduct, predatory intent, and a dangerous probability that the firm would actually achieve monopoly power. Rough tactics by a company with no realistic path to monopoly do not qualify.

Some conduct is illegal on its face

A short list of practices is so corrosive that courts condemn it without studying market effects. Competing firms that fix prices, rig bids, or divide up customers or territories commit per se violations of Section 1. No one may defend these deals by arguing the agreed price was fair. If two Missouri tech vendors sat down and split the state's market between them, the agreement itself would be the crime — no elaborate market analysis required.

Almost everything else gets judged under the rule of reason. A court weighs the practice's actual harm to competition against the defendant's procompetitive justifications. This is why antitrust cases turn on economics and evidence, not slogans. The same exclusivity contract that would be lawful for a small firm can violate Section 2 when a monopolist uses it to freeze out every rival at scale.

The government is already in court against big tech

These theories are not academic. In August 2024, a federal judge in Washington ruled in United States v. Google that Google illegally maintained its monopoly in general search, largely through contracts that made Google the default search engine on browsers and phones. The case moved into a remedies phase that continues to be contested. A separate federal court in Virginia found in 2025 that Google also unlawfully monopolized key advertising-technology markets. The DOJ Antitrust Division prosecuted both cases.

The Federal Trade Commission and a coalition of state attorneys general sued Amazon in 2023, alleging that the company uses anticompetitive tactics to protect its marketplace monopoly. A jury in California found that Google's Play Store rules violated antitrust law in a case brought by Epic Games. The FTC also enforces its own statute against unfair methods of competition.

Missouri is not a bystander. The Missouri Attorney General enforces RSMo chapter 416, can sue on behalf of Missouri residents in what lawyers call a parens patriae action, and has joined other states in federal antitrust suits against dominant tech platforms. A government win can also lower the hill for private plaintiffs, because a final government judgment may serve as evidence in follow-on private suits.

You can bring your own case, and the law triples your damages

Antitrust law gives private plaintiffs unusually strong remedies. Section 4 of the Clayton Act, 15 U.S.C. § 15, lets any person injured in business or property recover three times the damages sustained, plus a reasonable attorney's fee. Missouri matches that structure: RSMo § 416.121 allows an injured person — including the state — to sue in Missouri circuit court and recover threefold damages, attorney's fees, and costs. A Missouri reseller squeezed out of a marketplace, or an advertiser overcharged by an ad-tech monopoly, can bring these claims at home.

Two standing doctrines filter who may recover. First, Brunswick Corp. v. Pueblo Bowl-O-Mat, Inc., 429 U.S. 477 (1977), requires antitrust injury: your loss must flow from the anticompetitive aspect of the conduct, not from competition itself. A rival undersold by a more efficient competitor has a grievance, but not an antitrust claim. Second, Illinois Brick Co. v. Illinois, 431 U.S. 720 (1977), generally limits federal damages suits to direct purchasers — those who bought straight from the violator. Consumers who paid an overcharge passed down a distribution chain often cannot recover under federal law, though state statutes can differ, and the Merchandising Practices Act sometimes fills the gap for Missouri consumers. Whether a particular Missouri state-law path is open for indirect purchasers is a question worth putting to counsel, because the answer is not settled.

Class actions make small individual harms worth pursuing. When a platform overcharges millions of users by a few dollars each, no single user can justify a lawsuit, but a certified class can. One caution: many platform terms of service force disputes into individual arbitration and waive class treatment, which can block that route entirely.

Deadlines apply. Federal antitrust claims carry a four-year statute of limitations, and state claims have their own limitations periods. Evidence also decays: platforms change fee schedules, contracts get renewed, and messages disappear. If you suspect real harm, start documenting now rather than next year.

Know the defenses and limits before you file

Honest assessment saves you time and money. Several doctrines shield conduct that feels unfair but is lawful:

Competition itself. Antitrust law protects competition, not individual competitors. Low prices, rapid innovation, and aggressive expansion that benefit consumers are lawful even when they hurt rivals.
Petitioning the government. Under the Noerr-Pennington doctrine, named for Eastern Railroad Presidents Conference v. Noerr Motor Freight, Inc., 365 U.S. 127 (1961), lobbying and good-faith litigation are protected even when the petitioner hopes for anticompetitive results.
State action. Parker v. Brown, 317 U.S. 341 (1943), immunizes anticompetitive rules that a state adopts as clearly articulated policy, with active supervision for private actors.
Arbitration clauses. Platform terms often require individual arbitration, which can move your claim out of court and eliminate class treatment.
No duty to deal. A monopolist generally has no obligation to do business with rivals, absent special circumstances, so a platform cutting off access is not automatically liable.

A claim that ignores these limits will not survive a motion to dismiss. A claim built around them can succeed.

What to Do If You Suspect Antitrust Harm

You do not need to decide today whether you have a case. You do need to preserve your options:

Write down what happened. Record dates, prices, fee changes, and the names of the people you dealt with. Contemporaneous notes carry weight later.
Save the documents. Keep invoices, contracts, terms-of-service updates, screenshots, and email. Do not edit or annotate the originals.
Report the conduct. File a complaint with the Missouri Attorney General's office, the FTC, or the DOJ Antitrust Division. Government investigators act on patterns, and your report adds to the pattern.
Check your contracts. Look for arbitration clauses and class-action waivers before assuming you can join or start a class case.
Mind the clock. The federal limitations period is four years, and state deadlines vary. Waiting costs you leverage and can cost you the claim.
Talk to a lawyer who handles competition and consumer cases. Bring your timeline and documents to the consultation so the attorney can evaluate standing, forum, and remedies.

If a dominant platform's conduct has hurt your Missouri business, call Ott Law Firm at (314) 710-2740 or reach us through our contact page. You can also browse our blog for related guides on Missouri consumer and business law.

Common questions about tech antitrust in Missouri

Is it illegal for a tech company to dominate its market?

No. Dominance earned through a better product or sharper execution is lawful. Liability attaches only when a firm with monopoly power uses exclusionary conduct to acquire or keep that power, or when rivals conspire to restrain trade. The distinction between winning and cheating sits at the center of every monopolization case.

Can a Missouri consumer sue over app-store fees or inflated prices?

Sometimes. A direct purchaser can sue for treble damages under federal law, and Missouri's RSMo § 416.121 provides the same threefold recovery in state court. Consumers who paid an overcharge passed through an intermediary face the federal direct-purchaser bar, but Missouri's Merchandising Practices Act may still offer a remedy. The facts of how you were charged matter, so have a lawyer review them.

How long do I have to bring an antitrust claim in Missouri?

Federal law sets a four-year statute of limitations for private antitrust suits, generally running from when the injury occurred. Missouri state-law claims carry their own limitations periods, which differ by statute. Because the analysis depends on when you were harmed and which law you invoke, treat four years as the outer marker and act well before it.

Will an arbitration clause in the platform's terms block my claim?

It can. Many tech platforms require users and sellers to arbitrate individually and waive class actions. Courts enforce most of these clauses. A lawyer can check whether an exception applies — for example, whether the clause fails to cover your particular claim — but assume arbitration applies until someone reads the actual terms.

What this means for you

The gap between "this feels rigged" and "this violates antitrust law" is real, and it closes only with facts: a defined market, monopoly power, exclusionary conduct, and harm to competition that injured you. Missouri gives you more paths than most people realize — a state antitrust act that tracks federal doctrine, treble damages in state court, a consumer-protection statute, and an attorney general who enforces them all.

This article is for informational purposes only and does not constitute legal advice. Every matter is different, and reading it does not create an attorney-client relationship. If a dominant tech company's conduct has harmed you or your business, contact Ott Law Firm at (314) 710-2740 or through our contact page to discuss your situation.

Antitrust in the Tech Sector: Missouri's Legal Landscape