Governmental Regulation That Eliminated Price Discrimination

The federal law against price discrimination is the Robinson-Patman Act of 1936, codified at 15 U.S.C. § 13. It amended the Clayton Antitrust Act and makes it unlawful for a seller to charge competing buyers different prices for goods of the same grade and quality when the price gap isn’t justified by real cost differences and could substantially lessen competition.¹ The Act is still in force, and it can be enforced by federal agencies or by private plaintiffs suing for treble damages.

What Counts as Price Discrimination

The statutory concept is narrower than the everyday meaning. Charging different customers different amounts isn’t automatically illegal. The Act applies when a seller charges different prices to different purchasers for goods of the same grade and quality, and the difference isn’t explained by actual cost variations in producing, selling, or delivering those goods.² A manufacturer selling identical widgets to two competing retailers at a 20% price spread, with no cost-based reason for the gap, is the textbook scenario.

The Act also requires a reasonable possibility that the discrimination will harm competition. A one-time, small price variation between buyers who don’t even compete with each other is unlikely to trigger liability.

What the Act Covers and What It Doesn’t

The Robinson-Patman Act has real limits that catch people off guard. It applies to tangible goods only, not services, and to completed sales, not leases.² A consultant charging different clients different rates, or a software company licensing its product at varying prices, falls outside the statute. The law uses the word “commodities,” and courts have consistently read that to mean physical, tangible products.

The discriminatory sales must also occur in interstate commerce. Purely local transactions between a seller and buyers within the same state don’t qualify.³ There must be at least two actual completed sales at different prices; an offer or quote that never turns into a sale won’t do it.

Congress carved out purchases made by nonprofit institutions. Schools, colleges, universities, public libraries, churches, hospitals, and charitable organizations buying goods for their own use are exempt.

What the Act Prohibits

The central prohibition is a seller charging competing buyers different prices for the same goods when the effect may substantially lessen competition or help create a monopoly.³ A plaintiff doesn’t need to prove that competition was actually destroyed, only that there’s a reasonable possibility of competitive harm.

The Act reaches beyond sticker prices. It also prohibits discriminatory promotional payments and services. If a seller pays one retailer for advertising or provides display materials, in-store demonstrations, or special packaging, those benefits have to be offered to all competing customers on proportionally equal terms.² Those provisions exist because sellers and favored buyers had gotten creative, disguising price breaks as advertising allowances or exclusive promotional support.

Primary Line and Secondary Line Injury

Robinson-Patman claims recognize two distinct types of competitive injury, and the difference decides who can bring suit.

Primary line injury occurs at the seller’s level. This is where a seller uses discriminatory pricing to undercut and damage its own competitors. A manufacturer selling below cost in a specific region over a sustained period to drive a rival out of that market is the classic example.² The predatory pricing element makes these cases hard to prove, because the plaintiff has to show the seller had a realistic chance of recouping its losses once the competitor was gone.

Secondary line injury occurs at the buyer’s level. A supplier gives one customer a better price than a competing customer, and the favored buyer uses that advantage to undercut its rivals. These cases are more common. Courts can infer the necessary competitive harm from the existence of a significant price difference sustained over time, which makes the plaintiff’s burden lighter than in primary line cases.²

When Buyers Can Be Liable

Most of the Act targets sellers, but one provision reaches buyers. Section 2(f) makes it unlawful for a buyer to knowingly induce or receive a discriminatory price that the Act prohibits.⁴ A large retailer that pressures a supplier into a steep, unjustified discount can face liability alongside the supplier. The word “knowingly” is doing real work. A buyer who reasonably believes the lower price reflects legitimate cost savings, or is available to other customers on equal terms, has a solid defense.

Defenses Available to Sellers

The Act isn’t a blanket ban on all price differences. Three defenses come up regularly.

A cost justification defense allows different prices when the difference reflects genuine cost savings in manufacturing, selling, or delivering the product. Bulk orders that reduce per-unit shipping costs are the standard example. This defense is harder to prove than most sellers expect, because it requires solid accounting data showing the actual cost difference, and courts scrutinize the allocation methodology closely.²

A meeting-competition defense lets a seller lower its price in good faith to match a competitor’s equally low price. This is the most heavily used defense, because it protects a seller’s ability to respond in the market without turning every price cut into a potential violation.²

A changing-conditions defense covers price changes that respond to conditions affecting the marketability of the goods, including perishable items nearing spoilage, seasonal items becoming obsolete, court-ordered distress sales, and goods sold off as part of a business closure.³

Enforcement and Penalties

Both the Federal Trade Commission and the Department of Justice have authority to enforce the Act. The FTC can investigate potential violations and issue cease-and-desist orders requiring a company to stop discriminatory pricing.² The DOJ can bring criminal charges in the most serious cases.

Section 3 of the Act creates criminal liability for predatory pricing designed to destroy competition or eliminate a competitor. Violations can result in up to one year of imprisonment and a fine of up to $5,000.⁵ Criminal prosecutions under this section are rare; the DOJ has historically focused its criminal antitrust resources on horizontal price-fixing conspiracies instead.

Private Lawsuits and Treble Damages

For most businesses, the more meaningful enforcement route is a private lawsuit. Any person injured in business or property by a Robinson-Patman violation can sue in federal court and recover three times actual damages, plus the cost of the lawsuit and reasonable attorney’s fees.⁶ A retailer who lost $200,000 in sales because a competitor got an unjustified price break could recover $600,000 plus legal costs.

The statute of limitations for a private Robinson-Patman lawsuit is four years from the date the cause of action accrued, meaning the date the violation actually injured you.⁷ Courts have recognized exceptions that can extend that deadline. If the defendant actively concealed the discrimination, the clock may not start running until you discovered or reasonably should have discovered the violation. Ongoing discriminatory pricing can also reset the limitations period with each new discriminatory sale.

Courts can issue injunctions ordering the offending company to stop discriminatory practices going forward, and for a business trying to compete on level ground, that forward-looking relief can matter as much as the money.

1
Office of the Law Revision Counsel. 15 U.S. Code 13 – Discrimination in Price, Services, or Facilities
2
Federal Trade Commission. Price Discrimination: Robinson-Patman Violations
3
Office of the Law Revision Counsel. 15 USC 13 – Discrimination in Price, Services, or Facilities
4
LexisNexis. Robinson-Patman Act Section 2(f) Buyer Liability
5
United States Sentencing Commission. Review of Antitrust Sentencing Data
6
Office of the Law Revision Counsel. 15 U.S. Code 15 – Suits by Persons Injured
7
Office of the Law Revision Counsel. 15 USC 15b – Limitation of Actions