What is a market-maker sportsbook?
Short answer: A market-maker sportsbook sets its own prices and is willing to take large bets from professional bettors, using that money to sharpen its lines; Pinnacle is the best-known example. Most US books, DraftKings included, are retail books that often limit winning bettors and follow market makers' prices rather than lead them.
Two kinds of sportsbook
Market makers set their own prices, keep limits high and accept bets from professional bettors, using that money to make their lines more accurate. Pinnacle is the best-known example, along with some exchanges. Retail books, including DraftKings, FanDuel and most US books, compete on promotions and product; they often limit accounts that win consistently and tend to follow the market makers' prices rather than lead them.
Why it matters
- Reference price. A market maker's price is the market's best estimate, so it is the natural yardstick for a retail book's price (see which is sharper).
- Where gaps come from. Retail books update more slowly and shade popular sides, which opens gaps (see why lines differ).
- Limits. A gap you cannot bet in size, or at all, is information, not an opportunity.
OpenSlate compares the two kinds directly: DraftKings next to Pinnacle for every line both post on tonight's props. Market data, not advice.
How a market maker sets a line
A market maker opens with its own estimate, takes bets, and moves the price when informed money arrives. Because it accepts large bets from bettors it believes are skilled, each move carries information. Over a day, the line tends to settle where the most informed money stops moving it, which is why the closing price at a market maker is treated as the market's best estimate.
How a retail book differs
A retail book manages risk differently. It can limit the bettors who move markets, adjust prices to balance the money it takes in, and offer promotions to attract customers. Its lines are still useful, but they carry less of the market's information, and they often move after the market makers do.
Why it matters for comparing props
On player props, the gap between a market maker and a retail book is the starting point for any comparison. It is a measurement of disagreement. Whether it means anything depends on timing, news and the market, which is why OpenSlate shows the gap and the time each price was read, rather than a verdict.
For bettors, the distinction is practical. If you want to know what the market thinks, look at the market maker. If you want to know what you can actually bet, look at the books where you have an account. The difference between the two is the comparison OpenSlate measures.
Related questions
- Is DraftKings or Pinnacle sharper?: why one book's prices are treated as the market's reference, and where that stops being true.
- How do I calculate a no-vig price?: the three-step formula for removing the margin from any two-way price.
- What is a +EV player prop?: what positive expected value means and why automated screens can mislead.
- What is a Trap Over?: why a cheap-looking Over is listed apart instead of treated as value.
Every answer on these pages is market data and education. OpenSlate does not publish free picks and does not tell you what to bet; it shows prices and measurements.
More: Removing the vig: how to turn two prices into a fair probability · Why Pinnacle is the reference price · Closing line value, explained · Why parlays cost more than the same bets straight · Why player prop lines move · Is DraftKings or Pinnacle sharper on NBA player props? · How do I calculate a no-vig price? · What is a +EV player prop? · Why do DraftKings and Pinnacle prop lines differ? · What is a Trap Over? · Are NBA rebound unders profitable? · How do I compare sportsbook prop odds for free? · What does closing line value tell me? · How often do prop lines move before tip-off? · What is the vig on DraftKings player props? · How do injury reports move NBA prop lines? · Is it better to bet the over or the under on player props? · Can you make money betting player props? · Can you bet at Pinnacle from the US? · What free tools help with player prop betting? · Does betting DraftKings when it disagrees with Pinnacle work? · What does over/under mean on a player prop? · How do sportsbooks set player prop lines? · What is a sharp bettor? · How do I convert American odds to implied probability? · What is a steam move in sports betting? · What are alternate lines on player props?
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