What is a minimum advertised price, and how do you monitor it?

A minimum advertised price (MAP) is the lowest price a brand allows resellers to show in their advertising for a product. It limits the price a shopper sees in an ad or on a product page, not the price the reseller finally charges. MAP monitoring is the work of finding every place your products are advertised, recording the price shown, and flagging listings that show less than the MAP.

This guide explains how MAP differs from MSRP and resale price maintenance, what counts as an "advertised" price online, and how to run MAP price monitoring step by step.

This page is general information, not legal advice. Rules on minimum prices differ by country and by US state. Ask a lawyer before you write or enforce a MAP policy.

How is MAP different from MSRP and resale price maintenance?

The three terms describe different things. MSRP is a suggestion. MAP is a rule about advertising. Resale price maintenance is control over the actual selling price.

A law firm article on MAP policies puts the core difference simply: "MAP controls advertised prices only, not resale prices" (Grant Genovese & Baratta). A reseller under a MAP policy can still charge a lower price at checkout. It just cannot advertise that lower price.

What does US law say about MAP policies?

Here is the general picture, with the sources it comes from. It is a summary, not a full account.

• Colgate doctrine (1919). In United States v. Colgate & Co., the Supreme Court said a trader "may announce in advance the circumstances under which he will refuse to sell," as long as there is no purpose to create or maintain a monopoly (Cornell LII). Most MAP policies are written as a one-sided announcement for this reason. The FTC describes the same idea: a manufacturer that adopts a price policy on its own may deal only with retailers who follow it (FTC).
• Leegin (2007). In Leegin Creative Leather Products v. PSKS, the Supreme Court held that "Dr. Miles is overruled and vertical price restraints are to be judged by the rule of reason" (Cornell LII). Under that standard, courts weigh the competitive harms and benefits of a minimum price restraint instead of treating it as automatically illegal.
• State law differs. The FTC notes that "some state antitrust laws and international authorities view minimum price rules as illegal, per se" (FTC). One law firm writes that California treats resale price maintenance as per se unlawful under the Cartwright Act and that California courts have not clearly adopted Leegin (Grant Genovese & Baratta).
• Agreement versus announcement. The protection of Colgate depends on the brand acting alone. Guidance from the same law firm is to present the policy as a one-sided decision, avoid having resellers sign it, and avoid letting reseller complaints drive enforcement (Grant Genovese & Baratta).
• Outside the US. The UK Competition and Markets Authority says a supplier may be imposing resale price maintenance indirectly if it "prevents or limits your ability to advertise lower prices online," and names minimum advertised price policies as an example (GOV.UK). A MAP policy that is common in the US can be a problem in other markets.

Why do brands use a MAP policy?

Brands use MAP policies to keep advertised prices for their products from falling in a race to the bottom. The Supreme Court's Leegin opinion describes several reasons a manufacturer may want to limit price competition between its own resellers (Cornell LII):

• Free riding. A discounter can benefit from showrooms, demonstrations and trained staff that other retailers pay for. A price floor keeps those retailers willing to invest in service.
• Competition between brands. Less price competition among sellers of one brand can push them to compete on service and promotion, which helps that brand against rival brands.
• New products. A new brand can use the restraint to persuade capable retailers to invest in selling a product that shoppers do not yet know.

In practice, brands also use MAP to keep authorized retailers from leaving because a few sellers undercut everyone in ads.

What counts as an "advertised" price online?

The advertised price is the price a shopper sees before taking any buying action. Online, that line is not always clear. Your MAP policy should define each case below, because a monitoring system can only flag what the policy defines.

Our MAP pricing guide makes the same point: do not assume the advertised price equals the checkout price. Record what is shown, where it is shown, and leave the decision about whether it breaks the policy to the policy owner.

How does MAP monitoring work, step by step?

MAP monitoring turns your price list into a regular check of every public listing. Each step below feeds the next.

1. List products and approved prices. Build one table with each SKU, its identifiers (GTIN or UPC, model number, variant), its MAP, the policy version and the date that MAP took effect. Without dates, you cannot tell whether an old listing broke the current rule or an earlier one.
2. Find every listing. Search your authorized retailers, marketplaces, comparison sites and shopping ads for each product. New sellers appear all the time, so discovery has to run again on a schedule. Our guide on tracking competitor pricing across multiple retailers covers how to keep a source list current.
3. Match each listing to the right SKU. A listing for the 128 GB model is not a violation of the 256 GB model's MAP. Match on identifiers first, then on title, brand and variant attributes. Send unclear matches to a person instead of guessing.
4. Capture the advertised price on a schedule. Record the shown price, currency, any visible coupon or bundle, the seller and the time. How often you check depends on how fast prices move in your category. See the price monitoring guide for ecommerce for how to choose a check frequency.
5. Flag violations with evidence. Compare each captured price with the MAP in force at that time. When it is lower, save a screenshot, the URL, the timestamp and the seller name. Evidence matters because a reseller can change the price within minutes.
6. Act through the policy. Send each flag to the person who owns the policy. They decide whether it is a violation and what happens next, following the steps the policy already announced. Keep the legal decision separate from the data collection.

Before you scale this up, test one product against its source page by hand. Check that the variant is right and that missing fields stay empty instead of being filled with a guess.

What should you capture for each MAP violation?

Capture enough that someone who never saw the listing can confirm it later. This table is a practical minimum.

Why is MAP monitoring hard on marketplaces?

Marketplaces with many third-party sellers make monitoring hard for four reasons.

• Many sellers on one product page. One listing can carry offers from many sellers, and only one may be shown by default. You need every offer, not just the featured one.
• Fast price changes. Third-party sellers often use automated repricing that can move prices below MAP within hours (LegalClarity). A daily check can miss a violation that started and ended between checks.
• Unknown sellers. A seller name on a marketplace may not match any account in your reseller list. You may need to trace which distributor supplied them before the policy can be applied.
• Duplicate and mislabeled listings. The same product may appear under several titles or with wrong variant details, which makes matching harder.

Should you build or buy MAP monitoring?

You can buy a dedicated MAP monitoring tool, or you can get product data from a data API and write your own rules. Both work. The choice depends on how many products and channels you track and how much control you want.

With the build route, an AI agent can call a product data API for each listing URL, compare the returned price with your MAP table and write up any gaps with the URL and timestamp. A person should still review each flag before anyone contacts a reseller. If you plan to keep results over time, see how to build a product price history database.

How datawebot fits

datawebot turns supported store URLs into structured product and variant records that people and AI agents can use. Today, store extraction works for Shopify stores. Each variant comes back with its price and currency, any compare-at price the store shows, observed availability, the source URL and the retrieval time. It has an HTTP API with an OpenAPI spec and an llms.txt file, so an agent can learn how to call it; see connect your agent. datawebot returns what the store shows; it does not decide whether a listing breaks your policy and does not enforce it. New accounts get 100 trial credits and no card is needed; see pricing.

Frequently asked questions

Is a minimum advertised price policy legal in the US?

Under federal law, a unilateral MAP policy has generally been treated as lawful, based on the Colgate doctrine and the rule-of-reason standard from Leegin (Cornell LII). State law can be stricter, and the UK treats MAP policies as a possible form of resale price maintenance (GOV.UK). Ask a lawyer about your own policy.

Can a retailer sell below MAP?

Usually yes. A MAP policy covers the advertised price, not the final selling price, so a retailer can often charge less at checkout or in a private quote (Grant Genovese & Baratta). Check how your own policy defines "advertised."

What is the difference between MAP and MSRP?

MSRP is a suggested price that the reseller can ignore. MAP is the lowest price a reseller may advertise under the brand's policy.

How often should MAP monitoring run?

It depends on how fast prices change in your category. Marketplaces with automated repricing may need several checks a day. Stable retailer sites may need only one check a day or less.

What is a MAP violation?

A MAP violation is an advertised price below the MAP for that exact product, in a placement the policy covers, at a time the MAP was in force. The policy owner decides whether a flagged listing meets that test.