An offer is one seller's listing of a product at a price: the retailer, the price, the condition (new, used or refurbished), whether it is in stock, and when that was observed. One product usually has many offers at once, from different retailers and marketplace sellers. Price comparison is the work of collecting and ranking a product's offers.
Why it matters: Offer-level data, each with a timestamp, is what lets you say both "the cheapest place to buy this now" and "how this price has moved", and judge how fresh each price is.
Related: Marketplace seller, Price history, Condition grade · ShopSavvy Data API · API documentation
A marketplace seller is a third-party business that lists products on a retailer's site, such as a seller on Amazon, Walmart Marketplace or eBay, rather than the retailer selling its own stock (a first-party offer). The retailer hosts the listing and takes a fee; the seller sets the price and often ships the item. Several sellers can offer the same product on one marketplace.
Why it matters: Marketplace prices can be lower or higher than the retailer's own price and come with different return and shipping terms. The ShopSavvy Data API marks each offer with is_marketplace and the seller name so you can filter them.
Related: Offer, Buy Box, is_marketplace · ShopSavvy Data API
A first-party offer is a product sold by the retailer itself from its own stock, as opposed to a third-party marketplace seller listing on the retailer's site. "Sold and shipped by Walmart" or "Ships from and sold by Amazon" are first-party offers. They usually follow the retailer's standard return, warranty and price-match policies, which marketplace listings may not.
Why it matters: Shoppers and analysts often want the retailer's own price separately from marketplace prices, because the two move differently and carry different terms.
Related: Marketplace seller, is_marketplace, Offer
Product matching is deciding whether two listings, often at different stores, are the same product. It uses shared identifiers such as UPC or brand plus MPN where they exist, and otherwise compares titles, attributes, images and prices. The hard cases are variants (a different size or color), bundles, accessories sold under the main product's name, and refurbished or regional versions.
Why it matters: Every price comparison is only as good as its matching: a cheaper price for the wrong variant is not a saving, and a repricing rule fed a bad match moves your price the wrong way.
Related: UPC, MPN, Offer, Repricing
MSRP (manufacturer's suggested retail price) is the price a manufacturer recommends retailers charge, also called list price. Retailers are generally free to sell above or below it, and many "sale" prices are shown as a discount from MSRP. It differs from MAP, which is a floor on the advertised price rather than a suggestion.
Why it matters: MSRP is a reference point, not a market price. Comparing a current offer to its own price history is a better test of a deal than comparing it to MSRP.
Related: MAP pricing, Strikethrough price, Price history
A strikethrough price is the higher "was" or "list" price a retailer shows crossed out next to the current price, to present the current price as a discount. It may be the item's MSRP, its earlier price at that store, or a comparison price, and retailers define it differently. Rules on how long an item must have sold at the higher price before it can be shown as a "was" price vary by country and state.
Why it matters: The size of a strikethrough discount says little on its own. Price history shows whether the "was" price was ever the price people actually paid.
Related: MSRP, Price history
MAP (minimum advertised price) is the lowest price a brand allows its retailers and resellers to advertise for a product. It is set by the brand's MAP policy, usually as a condition of being an authorized seller, and it governs the advertised price rather than the final sale price. Brands monitor listings for MAP violations: retailers or marketplace sellers showing the product below the floor.
Why it matters: MAP protects a brand's pricing and its retailers' margins. Monitoring it by hand across many stores and sellers is impractical, which is why brands use MAP monitoring software.
Related: MSRP, Price monitoring, Marketplace seller · MAP monitoring with ShopSavvy for Business
The Buy Box is the main "Add to cart" offer on a product page at a marketplace such as Amazon or Walmart, where several sellers offer the same item. The marketplace picks which seller wins it based on price, fulfillment, seller performance and other factors, and the winner gets most of that product's sales.
Why it matters: For marketplace sellers, holding the Buy Box matters more than having the lowest listed price. Tracking who holds it over time shows when competitors undercut you.
Related: Marketplace seller, Repricing, Offer · Buy Box tracking in ShopSavvy for Business
Repricing is changing your own prices in response to competitors' prices, usually by rules such as "stay 1% below the lowest competitor but never below my floor". Repricing tools range from rule engines that recommend a price, which a person then applies, to systems that push new prices to a store or marketplace automatically, sometimes many times a day. Floors and ceilings keep a rule from pricing below cost or far above the market.
Why it matters: Good repricing depends on fresh, correctly matched competitor prices; a rule fed a stale or wrong match will move your price the wrong way.
Related: Price monitoring, Buy Box, Price elasticity · Repricing rules in ShopSavvy for Business
Price monitoring is tracking the prices of specific products over time, usually at competitors, and being alerted when they change. It can be done by giving a tool the URLs of competitor product pages, or by matching your products to retailers the tool already tracks. Refresh frequency (how often prices are re-checked) is the main cost and quality lever.
Why it matters: Knowing about a competitor's price change the same day, rather than when sales drop, is the point of monitoring. The refresh rate decides how fast you find out.
Related: Repricing, MAP pricing, Scheduled refresh · ShopSavvy for Business
Price history is the record of a product's price over time, ideally per retailer and with the date of each observation. It shows normal price ranges, how often and how deep sales go, and whether a current price is actually low. It cannot be collected retroactively: a price that was never recorded is gone.
Why it matters: History turns a single price into context. ShopSavvy's archive holds hundreds of millions of price observations, with price history back to 2011, dense from 2019.
Related: Offer, Price dispersion, Data licensing · ShopSavvy Data API · API documentation
Price dispersion is the spread of prices for the same product across sellers at the same time, often measured as the gap between the lowest and highest offer or as a percentage of the median. Economists use it as a sign of how much search effort pays off for shoppers. Online, dispersion persists even for identical items because of shipping, seller reputation and how prices are updated.
Why it matters: Where dispersion is high, comparing prices saves real money; it is also the signal analysts use to study competition between retailers.
Related: Offer, Price history, Price elasticity
Price elasticity of demand is how much the quantity sold changes when the price changes, expressed as the percentage change in demand divided by the percentage change in price. Products with elastic demand lose many sales when prices rise; inelastic ones barely react. Pricing optimization tools estimate elasticity from sales data to recommend prices.
Why it matters: Elasticity needs your own sales data. Competitor prices tell you the market, elasticity tells you how your customers respond to it; serious pricing uses both.
Related: Repricing, Price dispersion
A price match is a retailer's promise to sell an item at a competitor's lower advertised price, usually under conditions: the same model and condition, the competitor on an approved list, the item in stock, and proof such as a link. Policies vary by retailer and often exclude marketplace sellers and limited-time deals.
Why it matters: Shoppers use current competitor prices as proof for a price match, which is one reason a timestamp on every offer matters.
Related: Offer, Marketplace seller