{
  "version": "b2b-data-acceptance-audit-2.0",
  "input_window_utc": [
    "2026-09-27T00:00:00Z",
    "2026-09-28T00:00:00Z"
  ],
  "end_exclusive": true,
  "method": "At each fixed five-minute UTC grid point use latest locally observed row at or before grid, by exact base/venue/quote. Local age is not exchange last-trade age or network latency.",
  "venue_summary": [
    {
      "symbol": "BTC",
      "venue": "Binance Spot",
      "quote": "USDT",
      "grid_points": 288,
      "observed_rows": 231,
      "fresh_120s": 68,
      "no_prior_record": 0
    },
    {
      "symbol": "BTC",
      "venue": "Binance Spot",
      "quote": "USD",
      "grid_points": 288,
      "observed_rows": 0,
      "fresh_120s": 0,
      "no_prior_record": 288
    },
    {
      "symbol": "BTC",
      "venue": "Coinbase Spot",
      "quote": "USDT",
      "grid_points": 288,
      "observed_rows": 231,
      "fresh_120s": 59,
      "no_prior_record": 0
    },
    {
      "symbol": "BTC",
      "venue": "Coinbase Spot",
      "quote": "USD",
      "grid_points": 288,
      "observed_rows": 231,
      "fresh_120s": 59,
      "no_prior_record": 0
    },
    {
      "symbol": "BTC",
      "venue": "OKX Spot",
      "quote": "USDT",
      "grid_points": 288,
      "observed_rows": 231,
      "fresh_120s": 59,
      "no_prior_record": 0
    },
    {
      "symbol": "BTC",
      "venue": "OKX Spot",
      "quote": "USD",
      "grid_points": 288,
      "observed_rows": 231,
      "fresh_120s": 59,
      "no_prior_record": 0
    },
    {
      "symbol": "ETH",
      "venue": "Binance Spot",
      "quote": "USDT",
      "grid_points": 288,
      "observed_rows": 231,
      "fresh_120s": 68,
      "no_prior_record": 0
    },
    {
      "symbol": "ETH",
      "venue": "Binance Spot",
      "quote": "USD",
      "grid_points": 288,
      "observed_rows": 0,
      "fresh_120s": 0,
      "no_prior_record": 288
    },
    {
      "symbol": "ETH",
      "venue": "Coinbase Spot",
      "quote": "USDT",
      "grid_points": 288,
      "observed_rows": 231,
      "fresh_120s": 59,
      "no_prior_record": 0
    },
    {
      "symbol": "ETH",
      "venue": "Coinbase Spot",
      "quote": "USD",
      "grid_points": 288,
      "observed_rows": 231,
      "fresh_120s": 59,
      "no_prior_record": 0
    },
    {
      "symbol": "ETH",
      "venue": "OKX Spot",
      "quote": "USDT",
      "grid_points": 288,
      "observed_rows": 231,
      "fresh_120s": 59,
      "no_prior_record": 0
    },
    {
      "symbol": "ETH",
      "venue": "OKX Spot",
      "quote": "USD",
      "grid_points": 288,
      "observed_rows": 231,
      "fresh_120s": 59,
      "no_prior_record": 0
    }
  ],
  "sensitivity": [
    {
      "symbol": "BTC",
      "tolerance_seconds": 5,
      "grid_points": 288,
      "all_three_locally_fresh": 0
    },
    {
      "symbol": "ETH",
      "tolerance_seconds": 5,
      "grid_points": 288,
      "all_three_locally_fresh": 0
    },
    {
      "symbol": "BTC",
      "tolerance_seconds": 30,
      "grid_points": 288,
      "all_three_locally_fresh": 6
    },
    {
      "symbol": "ETH",
      "tolerance_seconds": 30,
      "grid_points": 288,
      "all_three_locally_fresh": 6
    },
    {
      "symbol": "BTC",
      "tolerance_seconds": 120,
      "grid_points": 288,
      "all_three_locally_fresh": 55
    },
    {
      "symbol": "ETH",
      "tolerance_seconds": 120,
      "grid_points": 288,
      "all_three_locally_fresh": 55
    },
    {
      "symbol": "BTC",
      "tolerance_seconds": 300,
      "grid_points": 288,
      "all_three_locally_fresh": 224
    },
    {
      "symbol": "ETH",
      "tolerance_seconds": 300,
      "grid_points": 288,
      "all_three_locally_fresh": 224
    }
  ],
  "correction": "The v1 four-row example called Coinbase's normalized updated time a source event. It is local collector time from Advanced Trade products; the v1 values remain frozen but that interpretation is superseded.",
  "limitations": [
    "One complete UTC day, two bases, selected local collectors; not venue-wide reliability, long-run coverage, executable quotes or a performance ranking.",
    "A fresh local Coinbase product row does not prove freshness of its underlying last trade; per-product source event time was not retained.",
    "Binance and OKX normalizers permit local-time fallback when raw timestamps are absent; the archived rows do not preserve a fallback flag.",
    "Absent USD quote markets in this selected feed are absence of that feed/pair, not necessarily an exchange outage."
  ]
}