This post, originally from @azuma_eth, provides a detailed explanation of the changes in Polymarket's fee structure: To briefly explain the Polymarket fee turmoil, Polymarket changed its fee formula three times overnight. Old: fee = C × p × feeRate × (p × (1 - p))^exponent Middle: fee = C × feeRate × (p × (1 - p))^exponent New: fee = C × feeRate × p × (1 - p) The old formula is straightforward. The middle formula omits "× p," meaning it multiplies by the price one less time, leading to an overall higher fee (because the price p is always less than 1). Furthermore, the lower the share price, the higher the fee, resulting in absurdly high fees when the price is close to 0. The new formula removes "^exponent" from the previous formula, meaning the default exponent is now 1. Based on the actual rates previously disclosed by the community, the previous exponent should have been less than 1. Since the theoretical maximum value of (p × (1-p)) is 0.25, increasing the exponent to 1 will generally lower the cost and make the rate curve smoother, avoiding the extreme case where the price approaches 0. For those interested, please refer to the original text: