diff --git a/src/analytics/metrics/semantic-provider.ts b/src/analytics/metrics/semantic-provider.ts
index 435f1d0..1961e67 100644
--- a/src/analytics/metrics/semantic-provider.ts
+++ b/src/analytics/metrics/semantic-provider.ts
@@ -40,12 +40,33 @@ import type { SemanticModelVersion } from './semantic-registry';
 /**
  * The version this provider is written against.
  *
- * UNVERIFIED: no supply-chain or licence review has been run for it in this
- * repo, and it has not been executed. It is a declared intent, not a
- * certification, and `providerReadiness()` reports it as such so nothing
- * downstream can mistake the constant for a green light.
+ * LICENCE BOUNDARY — the reason this is 0.209.0 and not 0.208.1.
+ *
+ * MetricFlow was relicensed by dbt Labs at 0.209.0. Verified against the
+ * LICENSE file at each git tag, 2026-09-07, not inferred from PyPI metadata
+ * (PyPI reports no licence field for either version, so a metadata check
+ * would have found nothing):
+ *
+ *   v0.208.1  Business Source License 1.1  — source-available, NOT open source
+ *   v0.209.0  Apache License 2.0
+ *
+ * The previous pin sat exactly one patch below that boundary. For a
+ * self-hosted platform whose premise is no proprietary runtime dependency,
+ * a BUSL component in the semantic layer is a licence defect, not a
+ * preference — BUSL restricts production use until its change date.
+ *
+ * STILL UNVERIFIED, and deliberately still reported as such: no supply-chain
+ * review has been run and MetricFlow has never been executed here (no Python
+ * runtime is provisioned). `providerReadiness()` continues to return
+ * `verified: false`. Fixing the licence does not make the provider proven.
  */
-export const METRICFLOW_PINNED_VERSION = '0.208.1';
+export const METRICFLOW_PINNED_VERSION = '0.209.0';
+
+/**
+ * The first MetricFlow release under Apache-2.0. Anything below this is BUSL
+ * and must not be pinned here; the test asserts the pin stays at or above it.
+ */
+export const METRICFLOW_FIRST_OPEN_SOURCE_VERSION = '0.209.0';
 
 /** The provider-neutral port. BI-P029's `SiaxSemanticProvider`. */
 export interface SiaxSemanticProvider {
diff --git a/tests/unit/metricflow-licence.test.ts b/tests/unit/metricflow-licence.test.ts
new file mode 100644
index 0000000..bf1dfb4
--- /dev/null
+++ b/tests/unit/metricflow-licence.test.ts
@@ -0,0 +1,37 @@
+import { describe, expect, it } from 'vitest';
+import {
+  METRICFLOW_FIRST_OPEN_SOURCE_VERSION,
+  METRICFLOW_PINNED_VERSION,
+} from '../../src/analytics/metrics/semantic-provider';
+
+/**
+ * BI-P147. MetricFlow below 0.209.0 is Business Source License 1.1 —
+ * source-available, NOT open source, and restricted for production use until
+ * its change date. dbt Labs relicensed to Apache-2.0 at 0.209.0, verified
+ * against the LICENSE file at each git tag on 2026-09-07 (PyPI reports no
+ * licence field for either version, so a metadata check finds nothing).
+ *
+ * This guards a boundary an ordinary "pin the version we tested" change would
+ * cross without noticing: the previous pin, 0.208.1, was one patch below it.
+ */
+const cmp = (a: string, b: string): number => {
+  const pa = a.split('.').map(Number);
+  const pb = b.split('.').map(Number);
+  for (let i = 0; i < Math.max(pa.length, pb.length); i += 1) {
+    const d = (pa[i] ?? 0) - (pb[i] ?? 0);
+    if (d !== 0) return d;
+  }
+  return 0;
+};
+
+describe('BI-P147 MetricFlow licence boundary', () => {
+  it('pins a version at or above the Apache-2.0 boundary', () => {
+    expect(cmp(METRICFLOW_PINNED_VERSION, METRICFLOW_FIRST_OPEN_SOURCE_VERSION)).toBeGreaterThanOrEqual(0);
+  });
+
+  it('rejects every known BUSL version — the comparison genuinely discriminates', () => {
+    for (const busl of ['0.207.3', '0.208.0', '0.208.1']) {
+      expect(cmp(busl, METRICFLOW_FIRST_OPEN_SOURCE_VERSION)).toBeLessThan(0);
+    }
+  });
+});