Circle Opens Hourly USDC Auctions Paying Minters a Rebate

This is a structural change in how USDC redemption liquidity is priced, shifting the clearing fee from Circle to minters who bid in the auction. It affects large stablecoin holders and market makers capable of participating hourly, who gain a new source of rebate income, while smaller minters may find the cadence impractical. The open question is whether the auction mechanism concentrates redemption flow among a few sophisticated participants, and whether the capped Express rate becomes the effective ceiling for all redemption pricing.