diff --git a/admin-compliance/app/sdk/agent/_components/CookieLibraryPanel.tsx b/admin-compliance/app/sdk/agent/_components/CookieLibraryPanel.tsx
index ad5141a8..c939588c 100644
--- a/admin-compliance/app/sdk/agent/_components/CookieLibraryPanel.tsx
+++ b/admin-compliance/app/sdk/agent/_components/CookieLibraryPanel.tsx
@@ -28,6 +28,12 @@ interface CheckData {
     real_cookies?: number
     other_storage?: number
   }
+  drift?: {
+    declared_count?: number
+    browser_count?: number
+    high_findings?: number
+    low_findings?: number
+  }
 }
 
 const SEV_COLOR: Record<string, string> = {
@@ -55,8 +61,24 @@ export function CookieFindingList({ data }: { data: CheckData }) {
   const findings = data.findings || []
   const s = data.summary || {}
   const inv = data.storage_inventory
+  const drift = data.drift
+  const driftShown =
+    !!drift && ((drift.declared_count ?? 0) + (drift.browser_count ?? 0)) > 0
   return (
     <div className="border rounded-lg overflow-hidden">
+      {driftShown && (
+        <div className="px-4 py-2.5 bg-amber-50 border-b text-xs text-amber-900">
+          <span className="font-semibold">Richtlinie ↔ Realität:</span>{' '}
+          <strong>{drift!.declared_count ?? 0}</strong> in der Cookie-Richtlinie
+          dokumentiert · <strong>{drift!.browser_count ?? 0}</strong> im Browser geladen
+          {(drift!.high_findings ?? 0) > 0 && (
+            <> · <strong className="text-red-700">{drift!.high_findings} undokumentiert geladen</strong></>
+          )}
+          {(drift!.low_findings ?? 0) > 0 && (
+            <> · {drift!.low_findings} dokumentiert, aber nicht geladen</>
+          )}
+        </div>
+      )}
       {inv && (inv.total ?? 0) > 0 && (
         <div className="px-4 py-2.5 bg-blue-50 border-b text-xs text-blue-900">
           <span className="font-semibold">Storage-Inventar:</span>{' '}
diff --git a/admin-compliance/app/sdk/agent/_components/__tests__/CookieLibraryPanel.test.tsx b/admin-compliance/app/sdk/agent/_components/__tests__/CookieLibraryPanel.test.tsx
index c0a46559..9e05ec19 100644
--- a/admin-compliance/app/sdk/agent/_components/__tests__/CookieLibraryPanel.test.tsx
+++ b/admin-compliance/app/sdk/agent/_components/__tests__/CookieLibraryPanel.test.tsx
@@ -27,6 +27,16 @@ describe('CookieFindingList', () => {
     expect(screen.getByText(/Keine Abweichungen/)).toBeInTheDocument()
   })
 
+  it('zeigt den Drift-Strip (Richtlinie vs. Browser-Realität)', () => {
+    render(<CookieFindingList data={{
+      summary: { checked: 31, in_library: 8, findings: 0 },
+      drift: { declared_count: 0, browser_count: 31, high_findings: 31, low_findings: 0 },
+      findings: [],
+    }} />)
+    expect(screen.getByText(/Richtlinie ↔ Realität/)).toBeInTheDocument()
+    expect(screen.getByText(/31 undokumentiert geladen/)).toBeInTheDocument()
+  })
+
   it('zeigt das Storage-Inventar (echte Cookies vs. andere)', () => {
     render(<CookieFindingList data={{
       summary: { checked: 100, in_library: 30, findings: 0 },
diff --git a/backend-compliance/compliance/api/agent_compliance_check_routes.py b/backend-compliance/compliance/api/agent_compliance_check_routes.py
index c8e51e90..bb7bdbeb 100644
--- a/backend-compliance/compliance/api/agent_compliance_check_routes.py
+++ b/backend-compliance/compliance/api/agent_compliance_check_routes.py
@@ -235,6 +235,9 @@ async def snapshot_cookie_check(snapshot_id: str):
     from compliance.services.cookie_storage_inventory import (
         build_storage_inventory, storage_transparency_finding,
     )
+    from compliance.services.cookie_compliance_audit import (
+        audit_cookie_compliance,
+    )
     db = SessionLocal()
     try:
         snap = load_snapshot(db, snapshot_id)
@@ -251,6 +254,15 @@ async def snapshot_cookie_check(snapshot_id: str):
             out["findings"].insert(0, tf)
             out["summary"]["findings"] = len(out["findings"])
         out["storage_inventory"] = inv
+        # ② Documentation Drift: Cookie-Richtlinie (Text) vs. Browser-Realität.
+        docs = snap.get("doc_entries") or []
+        cookie_text = next(
+            (e.get("text") or e.get("content") or "" for e in docs
+             if e.get("doc_type") in ("cookie", "cookie_richtlinie", "cookies")),
+            "",
+        )
+        out["drift"] = audit_cookie_compliance(
+            db, cookie_text, snap.get("banner_result"))
         return out
     finally:
         db.close()
diff --git a/backend-compliance/compliance/tests/test_cookie_drift.py b/backend-compliance/compliance/tests/test_cookie_drift.py
new file mode 100644
index 00000000..df930b0e
--- /dev/null
+++ b/backend-compliance/compliance/tests/test_cookie_drift.py
@@ -0,0 +1,49 @@
+"""② Documentation Drift — Cookie-Richtlinie (deklariert) vs. Browser-Realität.
+
+Pinnt den Vertrag, den der Endpoint (snapshot_cookie_check → out["drift"]) und
+das Frontend (CookieFindingList Drift-Strip) konsumieren: declared_count /
+browser_count / high_findings / low_findings + die undokumentiert-geladen-Liste.
+db=None → Library-Lookup übersprungen, Drift bleibt rein mengenbasiert.
+"""
+
+from __future__ import annotations
+
+from compliance.services.cookie_compliance_audit import audit_cookie_compliance
+
+
+def _banner(*cookie_names: str) -> dict:
+    return {"phases": {"after_accept": {
+        "cookies": [{"name": n} for n in cookie_names]}}}
+
+
+def test_undeclared_browser_cookies_are_high_drift():
+    # BMW-Fall: Richtlinie nennt nichts, Browser lädt Tracker → undokumentiert.
+    audit = audit_cookie_compliance(None, None, _banner("_ga", "_fbp"))
+    assert audit["declared_count"] == 0
+    assert audit["browser_count"] == 2
+    assert audit["high_findings"] == 2
+    assert set(audit["undeclared_in_browser"]) == {"_ga", "_fbp"}
+    assert audit["low_findings"] == 0
+
+
+def test_empty_inputs_yield_zero_drift():
+    audit = audit_cookie_compliance(None, None, None)
+    for k in ("declared_count", "browser_count", "high_findings", "low_findings"):
+        assert audit[k] == 0
+
+
+def test_drift_both_directions():
+    # Richtlinie deklariert 3 Cookies (Tab-Tabelle), Browser lädt 2 davon + 1 neuen.
+    doc = (
+        "Name\tKategorie\tZweck\tSpeicherdauer\n"
+        "_ga\tAnalytics\tBesucher unterscheiden\t2 Jahre\n"
+        "_gid\tAnalytics\tBesucher unterscheiden\t1 Tag\n"
+        "consent\tNotwendig\tEinwilligung speichern\t1 Jahr\n"
+    )
+    audit = audit_cookie_compliance(None, doc, _banner("_ga", "_gid", "_fbp"))
+    # _fbp ist geladen aber nicht deklariert → HIGH-Drift.
+    assert "_fbp" in audit["undeclared_in_browser"]
+    assert audit["high_findings"] >= 1
+    # consent ist deklariert aber nicht geladen → LOW-Drift.
+    assert "consent" in audit["declared_not_loaded"]
+    assert audit["low_findings"] >= 1