69% of Sharp Polymarket Price Moves Happened on Under $1,500

A sharp move on a prediction-market chart usually says little about what traders believe. Vultax traced every sharp move in Polymarket's 400 busiest open markets from 18 September to 2 October 2026 and read the public trade record for the minutes in which each one happened.

• 1,985 moves of 3 percentage points or more inside 30 minutes, in 224 of the 400 markets.
• In 1,375 of them, 69%, less than $1,500 changed hands while the price moved. In 766, less than $100 did.
• 400 moves, 20.2%, were one trader: a single wallet supplied half or more of the money.
• 70 moves, 3.5%, had many traders moving together with no dominant wallet.
• A day later, 47.6% of the moves that could be followed had given back half or more.

The markets are the 400 open Polymarket markets with the most volume over the previous week. For each one Vultax took the one-minute price series for 14 days and marked a move wherever the price changed by 3 percentage points or more within 30 minutes and by at least four times that market's usual half-hour swing.

For each move it then read the taker trades from ten minutes before the move began to two minutes after it ended: how much money traded, from how many wallets, and what share came from the largest one.

Most sharp moves were made with very little money. Where less than $1,500 traded, the median was $51 from a single wallet, and in 507 moves the price changed with no taker trade at all: quotes were moved or withdrawn, and the midpoint followed.

Where real money was involved, a single trader was far more common than a crowd. One-trader moves had a median of $4,588 behind them. The 70 broad moves had a median of $7,288 from 33 wallets.

The share of low-money moves falls as a market gets busier, but it stays high. Split the 1,985 moves into four equal groups by the market's weekly volume: in the quietest group, markets trading $54,000 to $78,000 a week, 81% of sharp moves happened on under $1,500. In the busiest group, $176,000 to $3 million a week, it was still 48%.

1,778 of the moves were old enough to follow for 24 hours. 47.6% of them had given back half or more by then, and the typical move kept 58% of its size. Broad moves held best: 35% of them gave back half or more, against 46% for one-trader moves and 48% for the low-money moves. Only 46 broad moves could be followed, so that gap is a lead and not yet a result.

A spike is a fact about the order book before it is a fact about the event. Before treating one as news, three things are worth knowing: how much money traded, whether one wallet supplied most of it, and whether other traders moved with it. All three are in the public trade record.

None of this says why anyone traded, and it does not show wrongdoing. A single large buyer may know something or may simply be large. What the record supports is narrower: in these two weeks, most sharp moves were not the market changing its mind.

The study was run twice on 2 October 2026 and gave the same result both times. Prices are Polymarket's one-minute series, which the venue keeps for 14 days; trades are its public taker-trade record. The trade query returns at most 1,000 trades per window, newest first, which can undercount money only in the very busiest minutes, where the move is not a low-money one in any case.

Limits: two weeks, open markets only, and a threshold of 3 points that treats a move from 2% to 5% like a move from 50% to 53%. The 400 markets are the busiest by weekly volume, so quieter markets, where thin books are the rule, are not in the count. Corrections: [email protected].