diff --git a/scripts/teeth-artifact-governance.js b/scripts/teeth-artifact-governance.js
index 5a539a3..2aa6ae6 100644
--- a/scripts/teeth-artifact-governance.js
+++ b/scripts/teeth-artifact-governance.js
@@ -292,6 +292,14 @@ inject(34, 'an artifact for another stat is accepted',
   `       || false)) {`,
   GOV);
 
+inject(35, 'an UNSUPPORTED row is attributed to the hits artifact',
+  'src/services/model/probabilityContract.js',
+  `      estimator_type: null, estimator_version: null, certification_version: null,
+      contract_model_version: null, artifact: null, artifact_id: null,
+      procedure_version: null,`,
+  ``,
+  GOV);
+
 const landed = results.filter((r) => r.landed).length;
 console.log(JSON.stringify({ teeth_landed: `${landed}/${results.length}`, results }, null, 2));
 process.exit(landed === results.length ? 0 : 1);
diff --git a/src/services/model/probabilityContract.js b/src/services/model/probabilityContract.js
index 9f71790..d14c004 100644
--- a/src/services/model/probabilityContract.js
+++ b/src/services/model/probabilityContract.js
@@ -173,7 +173,23 @@ function resolve(read = {}, deps = {}) {
   };
 
   if (!contract) {
-    return { ...base, probability_state: STATE.UNSUPPORTED, reason: 'no certified contract for this sport/stat' };
+    // NO ARTIFACT ATTRIBUTION ON AN UNSUPPORTED ROW.
+    //
+    // The contract check happens BEFORE any artifact is relevant: there is no
+    // certified contract for this sport/stat, so no artifact applies and naming
+    // one asserts a relationship that does not exist. Measured on cohort
+    // df4ec562: every one of 1,910 non-hits rows recorded
+    // `artifact_id: mlb-hits-isotonic@...` beside state UNSUPPORTED, so a query
+    // for "rows this artifact produced" would have returned 2,186 instead of
+    // 133. The probability never leaked; the attribution did.
+    return {
+      ...base,
+      estimator_type: null, estimator_version: null, certification_version: null,
+      contract_model_version: null, artifact: null, artifact_id: null,
+      procedure_version: null,
+      probability_state: STATE.UNSUPPORTED,
+      reason: 'no certified contract for this sport/stat',
+    };
   }
   if (read.model_version !== contract.model_version) {
     // A calibration artifact is only meaningful against the forecast it was
diff --git a/tests/unit/artifactGovernance.test.js b/tests/unit/artifactGovernance.test.js
index 02b370b..6e775fc 100644
--- a/tests/unit/artifactGovernance.test.js
+++ b/tests/unit/artifactGovernance.test.js
@@ -274,3 +274,48 @@ describe('ONE ARTIFACT, ONE STAT — the cross-stat leak found by cohort 0353c55
     expect(r.served_probability).toBeNull();
   });
 });
+
+describe('an UNSUPPORTED row attributes no artifact', () => {
+  const retention = require('../../src/services/retentionService');
+
+  it('names no artifact for a stat that has no contract', () => {
+    const r = pc.resolve({ sport: 'mlb', stat: 'doubles', model_version: ERA, p_win: 0.65 },
+      { estimate: est, artifact: good });
+    expect(r.probability_state).toBe(pc.STATE.UNSUPPORTED);
+    expect(r.served_probability).toBeNull();
+    // the attribution, not just the number
+    expect(r.artifact).toBeNull();
+    expect(r.artifact_id).toBeNull();
+    expect(r.estimator_type).toBeNull();
+    expect(r.procedure_version).toBeNull();
+    expect(JSON.stringify(r)).not.toContain(good.artifact_id);
+  });
+
+  it('but a hits row in the same batch still carries the full identity', async () => {
+    const contract = await svc.build(null, { sport: 'mlb', stat: 'hits' });
+    const c = retention.createCollector({
+      snapshotId: 's2', sport: 'mlb', modelVersion: ERA, codeSha: 't',
+      gameDate: '2026-09-03', gameIdFor: () => 'g',
+    });
+    for (const stat of ['hits', 'doubles']) {
+      c.onGraded({ player: `P ${stat}`, stat_type: stat, line: 0.5, sport: 'mlb', over_odds: -110, under_odds: -110 },
+        [{ direction: 'over', grade: 'C+', p_win: 0.65, confidence: 65 }]);
+    }
+    const merged = retention.mergeProbabilityContract(c.rows, contract);
+    const hits = merged.find((r) => r.stat === 'hits').probability_contract;
+    const doubles = merged.find((r) => r.stat === 'doubles').probability_contract;
+    expect(hits.artifact.artifact_id).toBe(good.artifact_id);
+    expect(hits.served_probability).not.toBeNull();
+    expect(doubles.artifact).toBeNull();
+    expect(doubles.served_probability).toBeNull();
+    expect(doubles.probability_state).toBe(pc.STATE.UNSUPPORTED);
+  });
+
+  it('an artifact IS still named where it is the relevant one', () => {
+    // uncertified (out of support) and version-mismatch rows keep attribution:
+    // there the artifact was consulted and is the thing that declined.
+    expect(pc.resolve(read(0.91), { estimate: est, artifact: good }).artifact).not.toBeNull();
+    expect(pc.resolve(read(0.65, { model_version: 'other' }), { estimate: est, artifact: good }).artifact)
+      .not.toBeNull();
+  });
+});
diff --git a/tests/unit/probabilityContract.test.js b/tests/unit/probabilityContract.test.js
index b5cec9f..72b136f 100644
--- a/tests/unit/probabilityContract.test.js
+++ b/tests/unit/probabilityContract.test.js
@@ -217,8 +217,9 @@ describe('probabilityContractService — loads, never fits', () => {
     const b1 = await svc.build(null, { sport: 'mlb', stat: 'hits' });
     const b2 = await svc.build(null, { sport: 'mlb', stat: 'hits' });
     for (const p of [0.50, 0.55, 0.601, 0.72, 0.799]) {
-      const a = b1.resolve({ model_version: ERA, p_win: p });
-      const c = b2.resolve({ model_version: ERA, p_win: p });
+      // the read NAMES its stat — the resolver no longer substitutes one
+      const a = b1.resolve({ sport: 'mlb', stat: 'hits', model_version: ERA, p_win: p });
+      const c = b2.resolve({ sport: 'mlb', stat: 'hits', model_version: ERA, p_win: p });
       expect(a.served_probability).toBe(c.served_probability);
       expect(a.artifact.knot_digest).toBe(c.artifact.knot_digest);
     }