If you’ve followed the NFL offseason, you know dead cap. It’s the salary cap charge a team takes for a player who isn’t on the roster anymore\u2014bonus money paid out years earlier, amortized across the original contract, still eating the budget long after the player was cut or traded. The Falcons carried over $40 million in dead cap going into 2024 after the Matt Ryan and Julio Jones era. The Broncos took a similar hit after the Russell Wilson trade. Dead cap doesn’t win games. It doesn’t put anyone on the field. It just sits there, taking up budget that could have been renegotiated to a current starter.<\/p>\n\n\n\n
Prediction markets have it too. Specifically, negative risk markets on Polymarket do. It’s the minimum allocation the underlying mechanics require for all active markets, even those that are all but eliminated.<\/p>\n\n\n\n
Polymarket’s NegRisk adapter pegs the sum of every Yes price in a multi-outcome market to $1. Every team gets a slice. The slices add up to a whole. The peg isn’t enforced by Polymarket itself\u2014it’s enforced by arbitrageurs. Whenever the sum of prices you can buy all at drifts above $1, an arbitrageur can split $1 into a complete set of Yes contracts (one for every team in the field) and sell each one at market, collecting more than the $1 they put in. When the sum drifts below $1, the reverse: buy a complete set for less than $1 and merge it back into $1. Arbitrageurs run this loop constantly, and the peg stays tight in real time.<\/p>\n\n\n\n
For our purposes, think of it as a salary cap. Polymarket has a fixed $1 budget for the World Cup market, and every team’s price has to fit under that cap. If France ought to win 30% of the time, France’s Yes should trade around $0.30. Argentina around $0.20. And so on, down through the field.<\/p>\n\n\n\n
Now here’s where dead cap comes in.<\/p>\n\n\n\n
The lowest price you can trade the World Cup on Polymarket is $0.001. One tenth of one cent. It’s a mechanical limit imposed by the platform\u2014you cannot bid or offer a contract below it. So the cheapest a deep longshot can possibly trade is the tick floor.<\/p>\n\n\n\n
Most deep longshots in a 48-team World Cup field are nowhere near that price as a fair value. Panama’s true probability of winning the World Cup isn’t 0.1%. It’s something well below\u2014pick your number, maybe 0.01%, maybe lower. But you can’t trade Panama Yes at $0.0001. You’re stuck at the $0.001 floor minimum. So Panama Yes is structurally overpriced relative to its true probability by something like an order of magnitude.<\/p>\n\n\n\n
That overpricing\u2014the gap between where the contract trades and where it ought to trade\u2014is dead cap. Budget allocated to an outcome that effectively can’t happen, eating the $1 cap without contributing anything real to the market’s price discovery.<\/p>\n\n\n\n
The tick floor sets the lower bound, but it doesn’t fully explain why deep longshots routinely trade right at it. A mechanical floor at $0.001 could still allow sparse trading. What you see on Polymarket instead is a wall: tens of millions of contracts deep on the bid side for outcomes like Panama, with matching depth on the ask one tick up. Not a thin floor. A wall.<\/p>\n\n\n\n
Polymarket’s maker rebate program is a tempting first explanation. The platform pays liquidity providers to post depth, and posting at the tick floor on a longshot is a low-effort, high-volume way to harvest those rebates. But the rebate pool allocated to a market like Panama is on the order of single-digit dollars per day. That’s nowhere near enough to incentivize tens of millions of contracts of standing depth. Whatever’s holding the wall up, the rebate program is at most a small contributor.<\/p>\n\n\n\n
It’s also worth ruling out the clean-sounding story that the wall is MMs scrambling for longshot Yes inventory. The MM that mints a complete set is usually doing so to satisfy favorite-side demand\u2014someone wants France or Argentina, the MM mints $1 into a complete set and sells off the favorite Yes to fill that demand. The longshot Yes contracts left in inventory afterward are surplus the MM would happily sell, not scarcity the MM is hunting. So if anything, the natural MM posture on longshots is on the offer side, not the bid side.<\/p>\n\n\n\n
Which leaves the bid wall itself as a genuine puzzle. The bids on Panama are sized at roughly 6x the asks at $0.002. If everyone has a Panama surplus worth nothing, why not dump them all off for whatever you can get? Maybe it’s not worth crossing the spread. But then how did the bids get there to begin with? These are sincere questions I still haven’t found a good explanation for. Whoever is absorbing the longshot supply at the floor is doing it for reasons I can’t cleanly account for from the outside.<\/p>\n\n\n\n
What I can say is that the empirical pattern holds regardless. Longshot Yes prices on Polymarket NegRisk markets sit at or near the tick floor for the duration of the market, with deep depth on both sides of the spread. The exact composition of who’s bidding and why is harder to pin down. The consequence is what we can read straight off the order book.<\/p>\n\n\n\n
So we have a $1 cap, a sustained longshot premium that sits there regardless of mechanism, and conservation arithmetic to resolve. The math is straightforward but the precise number depends on which price you measure. If 18 deep longshots in a 48-team World Cup market each carry a midpoint near $0.0015\u2014a $0.001 bid against a $0.002 ask\u2014the cumulative dead cap is around $0.027, roughly 2.7% of the $1 budget consumed by outcomes that effectively can’t happen. At the bid the figure is closer to $0.018; at the ask, $0.036. Pick whichever reference price reflects what you’d actually transact at.<\/p>\n\n\n\n
Distributed across the handful of meaningful favorites, you end up with each favorite trading somewhere in the 50 to 70 basis point range below its true probability. That’s the dead cap tax. France, Brazil, Argentina, England and every realistic contender is quietly discounted\u2014likely in proportion to their odds\u2014because Panama, Ghana, and the rest of the deep field are quietly overpriced.<\/p>\n\n\n\n
This is real edge, but it’s small edge. We’re not talking about a hot tip. We’re talking about a structural feature of Polymarket’s market design that gives the favorite-side bettor a small, persistent, structurally-explained discount. On a $100 bet on France, the dead cap tax might be worth $0.50 to $0.70 of expected value. You’re not going to retire on it. But you’re collecting it whether you know about it or not.<\/p>\n\n\n\n
One way the analogy bends: unlike NFL dead cap, the prediction market version isn’t permanent. As deep longshots get eliminated from the field through group stages and knockout rounds, their contracts settle at zero and their contribution to the budget vanishes. The favorite discount compresses through the tournament. By the time the field narrows to two teams in the final, there’s no dead cap left to redistribute. The discount is at its largest when the field is widest. If you want to capture the full structural edge, you’re betting favorites early in the tournament, not late. However, any edge early in the tournament probably doesn’t make up for the lack of APY on your positions.<\/p>\n\n\n\n
Kalshi doesn’t have a NegRisk-style atomic split-and-merge across the outcomes of a multi-team market, so there’s no $1 conservation peg holding the basket together. Each contract pair is its own market with its own collateral logic. Kalshi does have collateral return mechanics\u2014settlement releases collateral, and some series markets recognize mutual exclusivity for collateral purposes\u2014but none of those create a hard peg that has to redistribute mispricing across the basket the way NegRisk does. So the specific dead cap tax described here doesn’t operate on Kalshi.<\/p>\n\n\n\n
That’s not to say Kalshi favorites are priced fairly. Kalshi has its own distortions, most notably the overround on multi-outcome series, which often pushes favorite asks well above their true probabilities. And that’s generally more than the dead cap pushes Polymarket favorites below them. Different architectures, different distortions, opposite directions. The point of this piece isn’t that Kalshi is fairer than Polymarket. It’s that Polymarket’s specific architecture produces a specific, mechanical, persistent favorite discount that’s identifiable in the order book and capturable in expected value.<\/p>\n\n\n\n
Dead cap is what Polymarket pays for the elegance of atomic split-and-merge\u2014the same mechanism that gives the platform its tight conservation peg, its cross-outcome arbitrage, and its capital efficiency. The favorite-side discount is the giveback. The longshot mispricing is the cost. Both are structural, both are visible in the order book, and neither is going anywhere as long as the architecture stays this way.<\/p>\n\n\n\n
If you bet favorites on Polymarket, you’re collecting the giveback whether you meant to or not\u2014paid for, in part, by the longshot overpricing the same architecture produces. Not big enough to retire on. Real enough to know about.<\/p>\n","protected":false},"excerpt":{"rendered":"
If you’ve followed the NFL offseason, you know dead cap. It’s the salary cap charge a team takes for a player who isn’t on the roster anymore\u2014bonus money paid out years earlier, amortized across the original contract, still eating the budget long after the player was cut or traded. The Falcons carried over $40 million … Continue reading “Dead Cap Space: Why Polymarket Favorites Are Subtly Cheaper Than They Should Be”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":622,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[8],"tags":[],"_links":{"self":[{"href":"https:\/\/quantcha.com\/news\/wp-json\/wp\/v2\/posts\/621"}],"collection":[{"href":"https:\/\/quantcha.com\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/quantcha.com\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/quantcha.com\/news\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/quantcha.com\/news\/wp-json\/wp\/v2\/comments?post=621"}],"version-history":[{"count":1,"href":"https:\/\/quantcha.com\/news\/wp-json\/wp\/v2\/posts\/621\/revisions"}],"predecessor-version":[{"id":623,"href":"https:\/\/quantcha.com\/news\/wp-json\/wp\/v2\/posts\/621\/revisions\/623"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/quantcha.com\/news\/wp-json\/wp\/v2\/media\/622"}],"wp:attachment":[{"href":"https:\/\/quantcha.com\/news\/wp-json\/wp\/v2\/media?parent=621"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/quantcha.com\/news\/wp-json\/wp\/v2\/categories?post=621"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/quantcha.com\/news\/wp-json\/wp\/v2\/tags?post=621"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}