Arc’s first month: venue shares shift as two pairs dominate
Aero and StableFX gained turnover as Uniswap’s share fell below half. 99.5% of the month’s covered volume came from two pairs, and StableFX’s closing-week activity centred on one taker address.
Uniswap accounted for 81% of Florin-covered turnover in Arc’s opening week of public mainnet, but 46% in the closing week of its first month. Aero and StableFX both grew in absolute terms, even as total trading volume declined. The market became less concentrated by venue, while two pairs still accounted for almost all turnover.
Venue shares shift in a smaller market
Florin recorded 255.7m USDC of priced trading volume over the month. Uniswap remained the largest venue in that full-period total, at 160.5m USDC, followed by Aero at 66.3m and StableFX at 28.9m. But those totals conceal a substantial change in the closing weeks.
Between the first and final weeks, Uniswap’s turnover roughly halved, from 52.0m to 26.4m USDC. Aero’s rose from 10.4m to 19.1m, while StableFX’s increased from 1.88m to 11.81m. Their respective shares reached 33% and 21% in the final week, leaving Uniswap below half of covered volume.
Those gains took place in a slightly smaller market. Total weekly turnover fell 11%, from 64.3m to 57.4m USDC.
Euro-dollar trading gains weight
cirBTC/USDC, the market for Circle’s wrapped bitcoin token against USDC, supplied 196.6m USDC of monthly turnover, or 77% of the total. EURC/USDC contributed another 57.9m. Together, those two pairs accounted for 99.5% of covered volume.
The balance between them shifted. cirBTC/USDC turnover fell 24% between the opening and closing weeks, from 52.2m to 39.5m USDC. EURC/USDC rose 44%, from 12.2m to 17.5m. FX pairs consequently increased their share of covered trading from 19% to 31%.
StableFX was central to that change in venue mix. Its share of covered FX turnover rose from 15% to 66%. Yet the closing week’s activity was concentrated: all 342 completed StableFX settlements named the same taker address, alongside two maker addresses. The figures show substantial settlement activity, but do not establish a broad participant base.
Nor did the growing FX share mean many currencies traded at comparable scale. EURC/USDC accounted for 98% of the month’s 59.1m USDC in covered FX volume. GBPA/USDC contributed 1.19m; MXNB/USDC and AUDF/USDC together contributed less than 5,000 USDC. Venue diversity developed faster than currency diversity.
A quieter network, larger cross-chain inflows
Trading was only one part of Arc’s first-month activity. Florin’s network data records 48.2m transactions across the period. The opening week contributed 21.1m, against 6.86m in the final week, a decline of 68%. Launch day alone accounted for 7.76m transactions, but removing it does not eliminate the slowdown: the final week’s daily average was still 56% below the average for September 17–22.
Cross-chain USDC flows moved differently. Circle’s Cross-Chain Transfer Protocol, or CCTP, recorded 867.1m USDC arriving on Arc and 585.5m leaving over the month, a net inflow of 281.6m. The path was uneven: September 24 alone saw a net outflow of 108.0m USDC. Net inflows nevertheless increased from 32.2m in the opening week to 198.6m in the closing week. Here, too, concentration matters. One recipient address received 67% of the month’s inbound CCTP amount and 73% in the final week.
The first month leaves a specific question for the next: will the larger volumes at Aero and StableFX be joined by substantial, recurring activity across more currency pairs and counterparties? The clearest change so far is in where the covered trading happens. Evidence of a broader market will have to come from what trades and how widely participation is distributed.