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Adam Daniels
Adam Daniels

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Polymarket Sweeper Bots: Exploiting Post-Resolution Inefficiencies (Full Breakdown)

Polymarket Sweeper Bots: Exploiting Post-Resolution Inefficiencies

Most people try to profit on Polymarket by correctly predicting outcomes.

Sweeper bots do something completely different — they don’t predict anything.

They wait for the moment when the real-world outcome is already known, but the on-chain market hasn’t fully settled yet. During this window, shares that are guaranteed to resolve at $1 are sometimes sold below $1 due to panic, liquidity needs, misclicks, or poorly programmed bots.

This creates a deterministic (not probabilistic) arbitrage opportunity.

What Happens After Resolution

When an event resolves in reality (e.g., BTC clearly closes above a strike), there’s often a delay between:

  • The outcome becoming obvious
  • The final on-chain settlement

During this gap, trading remains open. The “correct” side is effectively worth exactly $1, but sellers still hit the market at lower prices.

The Core Strategy: Bidding Near $1

Instead of trying to buy cheap, sweeper bots bid very close to $1 (e.g., 0.995 – 0.999).

If filled:

  • You pay ~$0.999
  • You receive $1.00 at settlement

Your profit is the small spread. The edge comes from being first in line when someone sells, not from finding a huge discount.

FIFO Queue Competition

Polymarket uses FIFO (First In, First Out) matching.

If multiple bots bid at the same price, the one that placed the order earliest gets filled first. This shifts the competition from price to timestamp.

This is why the strategy evolved:

  • Old bots: Bid after market close
  • Better bots: Bid seconds before close
  • Current sweeper bots: Enter when probability reaches ~97-99% (while still taking some risk)

Key Technical Requirements

To run this effectively, you need:

  • Real-time price feeds (Binance, Coinbase, etc.) to detect when an outcome is effectively decided
  • Low-latency infrastructure (fast Polygon RPC, persistent WebSocket connection to Polymarket)
  • Fast order placement (pre-signed transactions or optimized signing)
  • Smart capital allocation — spreading bids across slightly different prices and multiple markets instead of parking everything at 0.999

Why the Edge Still Exists (But Is Harder)

Early on, this was extremely profitable because few bots existed and users made more mistakes.

Today the edge is smaller due to:

  • More sophisticated bots competing for queue position
  • Better overall infrastructure
  • Additional fees

The winners are no longer the ones who “know the idea” — they’re the ones with faster execution, better timing logic, and smarter risk management.

Public Example

One public wallet running this style of strategy reportedly made $8,383 in 3 weeks.

You can track it here: polymarket.com profile

This approach turns Polymarket from a prediction game into a system design and infrastructure game.


Based on public insights shared by @pmtraderadam. Always do your own research and trade responsibly.

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