{"id":198725,"date":"2026-07-15T17:33:41","date_gmt":"2026-07-15T17:33:41","guid":{"rendered":"https:\/\/mycryptomania.com\/?p=198725"},"modified":"2026-07-15T17:33:41","modified_gmt":"2026-07-15T17:33:41","slug":"traders-took-8-2-million-from-polymarkets-five-minute-bitcoin-bets-study-found","status":"publish","type":"post","link":"https:\/\/mycryptomania.com\/?p=198725","title":{"rendered":"Traders Took $8.2 Million From Polymarket\u2019s Five-Minute Bitcoin Bets, Study Found"},"content":{"rendered":"

Bitcoin Magazine<\/a><\/p>\n

Traders Took $8.2 Million From Polymarket\u2019s Five-Minute Bitcoin Bets, Study Found<\/a><\/p>\n

<\/div>\n

A new study argued that Polymarket\u2019s five-minute Bitcoin contract became a machine for wealth transfer. It moved money from retail bettors to a small band of manipulators, and it made Bitcoin\u2019s spot price worse in the process.<\/p>\n

The paper<\/a>, \u201cSettlement Manipulation in Prediction Markets\u201d by David Dai, Ruizhe Jia, and Shihao Yu of Stanford and Singapore Management University, studied a product that did not exist before February 12, 2026.\u00a0<\/p>\n

On that date Polymarket launched a binary contract that paid $1 if Bitcoin closed a five-minute window above where it opened, and $0 otherwise. A fresh contract opened every five minutes around the clock.\u00a0<\/p>\n

Within months, Polymarket\u2019s five- and fifteen-minute crypto<\/a> up\/down markets traded more than $4 billion and tripled the platform\u2019s daily volume. The flaw in polymarket was when the contract settled against a Chainlink oracle that averaged Bitcoin\u2019s price across major spot exchanges.\u00a0<\/p>\n

A trader who held the contract could buy or sell real Bitcoin<\/a> in the closing seconds, drag that reference price across the strike, and win the bet.<\/p>\n

The oracle\u2019s blend of exchanges looked like a defense, because moving it seemed to require moving many venues at once. The authors showed it was not much of a defense. Binance, the largest crypto exchange, sat about two and a half basis points from the oracle and moved near one-for-one with it. It finished on the same side of the strike as the resolution about 85%of the time. A push that drove the Binance price a few basis points past the strike carried the outcome.<\/p>\n

The pattern was in the Binance data. After the five-minute contract went live, net order flow in the final ten seconds before each close jumped about 50% above the pre-launch level. The spike was sharpest where a push mattered: in the 6% of cycles the market judged near-even, the jump was about 3.9 times the rest.<\/p>\n

The reversal gave it away. Real information stays in a price; a manipulative push does not. Within ten seconds the price reverted, by about a quarter in the near-even cycles. The pushes clustered in thin hours, when a dollar of flow moved the price the most: 56% landed overnight and 44%on weekends.<\/p>\n

Who won, who paid with these Polymarket bets<\/h2>\n

In near-even cycles, a push against the favored side flipped the winner 65% of the time, against 41% in normal trading. Even when one side held a 90-to-100% chance before the close, a push against it reversed the outcome 34% of the time, against 1% in cycles with no push. A bet the market treated as near-certain lost one time in three.<\/p>\n

Because Polymarket<\/a> settled on a public blockchain, the authors traced each wallet. Just 821 traders fit the manipulator profile, about one in three hundred of the 243,000 who traded the contract. They took $8.2 million in the pushed cycles and broke even in the rest. Of the losses, 93% fell on retail.<\/p>\n

The authors ruled out hedging as the innocent explanation. A binary contract carried little exposure to hedge once one side was near-certain, yet those were the cycles a push flipped. And the trades arrived in one burst in the final fifty seconds, not as a position built over the window.<\/p>\n

The remedy<\/h2>\n

The fix was the contract\u2019s horizon. Manipulation was absent from the fifteen-minute contract, because a longer window took in more ordinary trading before the close and made a fixed push a weaker force. The stakes reached past crypto: Nasdaq and Cboe each filed with the SEC to list binary asset-price contracts on equity indices, which would carry the same risk onto larger markets.<\/p>\n

This post Traders Took $8.2 Million From Polymarket\u2019s Five-Minute Bitcoin Bets, Study Found<\/a> first appeared on Bitcoin Magazine<\/a> and is written by Micah Zimmerman<\/a>.<\/p>","protected":false},"excerpt":{"rendered":"

Bitcoin Magazine Traders Took $8.2 Million From Polymarket\u2019s Five-Minute Bitcoin Bets, Study Found A new study argued that Polymarket\u2019s five-minute Bitcoin contract became a machine for wealth transfer. It moved money from retail bettors to a small band of manipulators, and it made Bitcoin\u2019s spot price worse in the process. The paper, \u201cSettlement Manipulation in […]<\/p>\n","protected":false},"author":0,"featured_media":198726,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[],"class_list":["post-198725","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-discovery"],"_links":{"self":[{"href":"https:\/\/mycryptomania.com\/index.php?rest_route=\/wp\/v2\/posts\/198725"}],"collection":[{"href":"https:\/\/mycryptomania.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mycryptomania.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"replies":[{"embeddable":true,"href":"https:\/\/mycryptomania.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=198725"}],"version-history":[{"count":0,"href":"https:\/\/mycryptomania.com\/index.php?rest_route=\/wp\/v2\/posts\/198725\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/mycryptomania.com\/index.php?rest_route=\/wp\/v2\/media\/198726"}],"wp:attachment":[{"href":"https:\/\/mycryptomania.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=198725"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mycryptomania.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=198725"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mycryptomania.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=198725"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}