What a suspicious trade is
A suspicious trade is a stored Polymarket fill that scored as unusual enough to review. The flag says the trade deserves a closer look, and nothing more. It does not identify an insider, prove advance knowledge, or establish intent, and 0xinsider never presents a flagged wallet as evidence of insider trading.
The scoring runs over the trades we ingest and store, not the full on-chain ledger. Missing rows, delayed messages, and identity gaps all limit what a flag can mean. The ingestion rules are published at 0xinsider.com/transparency.
Four signals and three tracks
The main track tests four signals on each fill. New wallet: 2 weeks old or less, with 10 trades or fewer. Size: $30,000 or more on the one fill. Price: a buy between 10¢ and 35¢, or a sell between 65¢ and 90¢; a near-certain price carries no edge, so anything past those bounds scores zero. Cluster: 3 or more wallets moving together on a quiet market. The size test is required: a fill needs $30,000 or more plus at least 2 of the other 3 signals, and its weighted score has to reach 60 of 100.
Two narrower tracks catch what the main one misses. The first flags a nearly brand-new wallet that buys between 10¢ and 15¢, or sells between 85¢ and 90¢, from $2,000 up, without the size and cluster tests. The second flags a position split into slices: 10 or more fills adding up to $150,000 or more in one market within 6 hours, from a wallet that has traded no more than 2 markets. Crypto up-or-down markets score zero, because nobody can know those outcomes early.
Every flag stores the signals that fired, so a reviewer can see why it scored. None of the signals reads the news.
Why a flag is not an accusation
Every signal has innocent explanations. A new wallet can be a researcher who did the work. A long-shot buy that wins can be a good read or luck, and luck is common across enough trades. Size can be a hedge against exposure held elsewhere. A cluster can be several wallets reading the same public news at the same time. None of these patterns proves advance knowledge, coordination, identity, intent, or illegality.
Academic work on prediction markets frames it the same way. The ForesightFlow research program on arXiv treats possible information leakage as a statistical detection problem: score the anomaly, then investigate. A flag opens an investigation; it never closes one.
How to review a flagged trade
Start with the track and the signals that fired, not the score alone. Check the market: its resolution rules, its liquidity at the time, and whether public news landed near the trade. Check the wallet: how much history it has, its past markets, and whether the trade fits its pattern or breaks it. Write down what is unknown instead of guessing.
Flagged trades appear at 0xinsider.com/trades/suspicious. For wash trading, manipulation, and other patterns, read the guide at 0xinsider.com/learn/how-to-spot-insider-trading-polymarket.
What a suspicion score cannot tell you
The score is not a probability that a trade was informed, and it is not a prediction that the position will win. A high score on incomplete inputs can mean less than a moderate score on complete ones. Several flagged wallets do not prove several independent people, and one wallet can be several people.
The score answers one narrow question: where to look next. The judgment after that look belongs to you.
Common questions
Does a suspicious-trade flag prove insider trading?
No. A flag marks a statistically unusual trade and puts it up for review. Wallet age, size, price, and clustering patterns all have innocent explanations, and the score does not establish advance knowledge, coordination, identity, intent, or illegality.
What signals flag a suspicious trade?
On the main track: a new wallet (2 weeks old or less, 10 trades or fewer), a fill of $30,000 or more, a buy between 10¢ and 35¢ or a sell between 65¢ and 90¢, and 3 or more wallets moving together. A trade needs the $30,000 fill plus 2 of the other 3, and a weighted score of 60 or more. Two narrower tracks catch long-shot trades from brand-new wallets and large positions split into many fills. Every flag stores the signals that fired.
Where can I see flagged trades?
At 0xinsider.com/trades/suspicious, built from the same stored trade records as the rest of 0xinsider. Suspicious trades are a Pro feature.
