# C850 — Freeze the full paired-anchor inverse field

## Question

Can one digit-register rule explain every existing pair of File52c endpoints?

## Inputs

```json
{}
```

## Sources

```json
[
  "latest File52c §2.1 and AppendixA.2–A.3; inverse preparation audit"
]
```

## Opened utc

2026-09-28T02:35:14.463028+00:00

## Results

```json
{
  "packet": {
    "path": "model/inverse_inputs.json",
    "sha256": "dbcb35bf6cfe88b318b4c8c327e97aa0be06583d5e945c43c9aac8b7f7b80911",
    "bytes": 19844
  },
  "scope": "existing32 sources and64 endpoints; target columns excluded; original input durations only",
  "hypothesis": "anchor dependence is generated by decimal borrow, core length and retained zero-placeholders"
}
```

## Finding

The entire original paired field is the next fixed reconstruction target. No extra dates, target counts, or second-pass reversal are admitted.

## Reassessment

Close the first20-step checkpoint, then test the paired field.

## Checks

```json
{
  "packet_present": true,
  "known_primary": true
}
```

## Closed utc

2026-09-28T02:35:14.464217+00:00

## Record provenance

Exact record hash: `ea0de96319b30884989dd06a7e3b87c647f519f5e14c49394d0857ebd59eb8dc`

Source journal: `Research_Cycles/C0832_C0931/journal.json`