diff --git a/.github/scripts/comment-licence-results.py b/.github/scripts/comment-licence-results.py
new file mode 100644
index 0000000..9c1a334
--- /dev/null
+++ b/.github/scripts/comment-licence-results.py
@@ -0,0 +1,153 @@
+"""Post a licence finding from an unprivileged ORT run on its pull request."""
+
+import html
+import io
+import json
+import os
+import re
+from pathlib import Path
+from urllib.parse import urlparse
+from urllib.error import HTTPError
+from urllib.request import HTTPRedirectHandler, Request, build_opener, urlopen
+from zipfile import ZipFile
+
+
+MARKER = "<!-- ort-licence-compliance -->"
+API = "https://api.github.com"
+
+
+def api(path, method="GET", body=None):
+    data = json.dumps(body).encode() if body is not None else None
+    request = Request(
+        API + path,
+        data=data,
+        method=method,
+        headers={
+            "Authorization": f"Bearer {os.environ['GH_TOKEN']}",
+            "Accept": "application/vnd.github+json",
+            "X-GitHub-Api-Version": "2022-11-28",
+            "Content-Type": "application/json",
+        },
+    )
+    with urlopen(request) as response:
+        return json.load(response)
+
+
+def cell(value):
+    content = html.escape(str(value).replace("|", "\\|").replace("\n", " ")[:300])
+    return f"<code>{content}</code>"
+
+
+class NoRedirect(HTTPRedirectHandler):
+    def redirect_request(self, request, fp, code, message, headers, new_url):
+        return None
+
+
+def result_files(repo, run_id):
+    artifacts = api(f"/repos/{repo}/actions/runs/{run_id}/artifacts?per_page=100")["artifacts"]
+    matches = [item for item in artifacts if item["name"] == "ort-licence-results" and not item["expired"]]
+    if not matches:
+        raise ValueError("ORT run has no results artifact")
+
+    path = f"/repos/{repo}/actions/artifacts/{matches[0]['id']}/zip"
+    request = Request(API + path, headers={"Authorization": f"Bearer {os.environ['GH_TOKEN']}"})
+    try:
+        build_opener(NoRedirect()).open(request)
+    except HTTPError as error:
+        if error.code != 302:
+            raise
+        location = error.headers["Location"]
+    else:
+        raise ValueError("GitHub did not redirect to the artifact archive")
+    if urlparse(location).scheme != "https":
+        raise ValueError("Artifact archive did not use HTTPS")
+
+    with urlopen(location) as response:
+        payload = response.read(20_000_001)
+    if len(payload) > 20_000_000:
+        raise ValueError("ORT result artifact is unexpectedly large")
+    with ZipFile(io.BytesIO(payload)) as archive:
+        return {
+            name: archive.read(name)
+            for name in ("pr-number", "evaluation-result.json")
+            if name in archive.namelist() and archive.getinfo(name).file_size <= 10_000_000
+        }
+
+
+def failure_body(files, run_url):
+    lines = [MARKER, "## Licence compliance failed", ""]
+    if "evaluation-result.json" in files:
+        try:
+            violations = json.loads(files["evaluation-result.json"])["evaluator"]["violations"]
+        except (ValueError, KeyError, TypeError):
+            violations = None
+        if violations is None:
+            lines.append("ORT produced an unreadable evaluation result. Check the workflow log.")
+        elif violations:
+            lines.extend(["| Package | Licence | Finding |", "| --- | --- | --- |"])
+            for violation in violations[:20]:
+                lines.append(
+                    f"| {cell(violation['pkg'])} | {cell(violation.get('license') or 'Unknown')} "
+                    f"| {cell(violation['message'])} |"
+                )
+            if len(violations) > 20:
+                lines.append(f"\n{len(violations) - 20} more findings are in the workflow result.")
+        else:
+            lines.append("ORT failed without a policy violation. Check the workflow log.")
+    else:
+        lines.append("ORT did not produce an evaluation result. Check the workflow log.")
+    lines.extend(["", f"[View the ORT run]({run_url})"])
+    return "\n".join(lines)
+
+
+def main():
+    event = json.loads(Path(os.environ["GITHUB_EVENT_PATH"]).read_text())
+    run = event["workflow_run"]
+    if run["event"] != "pull_request" or run["conclusion"] not in {"success", "failure"}:
+        return
+
+    repo = os.environ["GITHUB_REPOSITORY"]
+    files = result_files(repo, run["id"])
+    raw_number = files["pr-number"].decode().strip()
+    if not re.fullmatch(r"[1-9][0-9]*", raw_number):
+        raise ValueError("Invalid pull request number in ORT artifact")
+
+    number = int(raw_number)
+    associated_prs = run.get("pull_requests", [])
+    if associated_prs and number not in {item["number"] for item in associated_prs}:
+        raise ValueError("ORT artifact names a different pull request from the workflow run")
+    pr = api(f"/repos/{repo}/pulls/{number}")
+    if pr["base"]["repo"]["full_name"] != repo or run["head_sha"] not in {
+        pr["head"]["sha"],
+        pr["merge_commit_sha"],
+    }:
+        raise ValueError("ORT run does not match the pull request's current head")
+
+    existing = None
+    page = 1
+    while True:
+        comments = api(f"/repos/{repo}/issues/{number}/comments?per_page=100&page={page}")
+        for comment in comments:
+            if comment["user"]["login"] == "github-actions[bot]" and MARKER in comment["body"]:
+                existing = comment
+                break
+        if existing or len(comments) < 100:
+            break
+        page += 1
+
+    if run["conclusion"] == "failure":
+        run_url = f"https://github.com/{repo}/actions/runs/{run['id']}"
+        body = failure_body(files, run_url)
+    elif existing:
+        body = f"{MARKER}\n## Licence compliance passed\n\nThe current ORT run passed."
+    else:
+        return
+
+    if existing:
+        api(f"/repos/{repo}/issues/comments/{existing['id']}", "PATCH", {"body": body})
+    else:
+        api(f"/repos/{repo}/issues/{number}/comments", "POST", {"body": body})
+
+
+if __name__ == "__main__":
+    main()
diff --git a/.github/workflows/licence-compliance-comment.yml b/.github/workflows/licence-compliance-comment.yml
new file mode 100644
index 0000000..fa5ea3c
--- /dev/null
+++ b/.github/workflows/licence-compliance-comment.yml
@@ -0,0 +1,21 @@
+name: Licence compliance PR comment
+on:
+  workflow_run:
+    workflows: [Licence compliance pilot]
+    types: [completed]
+permissions:
+  contents: read
+  actions: read
+  pull-requests: write
+jobs:
+  comment:
+    if: github.event.workflow_run.event == 'pull_request' && (github.event.workflow_run.conclusion == 'success' || github.event.workflow_run.conclusion == 'failure')
+    runs-on: blacksmith-2vcpu-ubuntu-2404
+    steps:
+      - uses: actions/checkout@v7.0.1
+        with:
+          persist-credentials: false
+      - name: Update PR comment
+        env:
+          GH_TOKEN: ${{ github.token }}
+        run: python3 .github/scripts/comment-licence-results.py
diff --git a/.github/workflows/licence-compliance.yml b/.github/workflows/licence-compliance.yml
new file mode 100644
index 0000000..5baa434
--- /dev/null
+++ b/.github/workflows/licence-compliance.yml
@@ -0,0 +1,77 @@
+name: Licence compliance pilot
+on:
+  pull_request:
+  workflow_dispatch:
+permissions:
+  contents: read
+jobs:
+  licence-compliance:
+    runs-on: blacksmith-2vcpu-ubuntu-2404
+    timeout-minutes: 20
+    steps:
+      - uses: actions/checkout@v7.0.1
+        with:
+          persist-credentials: false
+      - name: Record PR for the comment workflow
+        if: github.event_name == 'pull_request'
+        env:
+          PR_NUMBER: ${{ github.event.pull_request.number }}
+        run: |
+          mkdir -p "$RUNNER_TEMP/ort-results"
+          printf '%s\n' "$PR_NUMBER" > "$RUNNER_TEMP/ort-results/pr-number"
+      - name: Analyse NuGet dependencies with ORT
+        run: |
+          mkdir -p "$RUNNER_TEMP/ort-results" "$RUNNER_TEMP/ort-project" "$RUNNER_TEMP/ort-home"
+          cp -a "$GITHUB_WORKSPACE/." "$RUNNER_TEMP/ort-project/"
+          docker run --rm --user "$(id -u):$(id -g)" \
+            --mount "type=bind,source=$RUNNER_TEMP/ort-project,target=/project" \
+            --mount "type=bind,source=$RUNNER_TEMP/ort-results,target=/results" \
+            --mount "type=bind,source=$RUNNER_TEMP/ort-home,target=/home/ort" \
+            ghcr.io/oss-review-toolkit/ort:92.0.0@sha256:b756f9ae0b8d6b435012a1b7097d4e419d327029cd8daeb36c7f400af9b51d31 \
+            --warn analyze -i /project -o /results -f JSON
+      - name: Evaluate licence policy
+        run: |
+          set +e
+          docker run --rm --user "$(id -u):$(id -g)" \
+            --mount "type=bind,source=$RUNNER_TEMP/ort-project,target=/project,readonly" \
+            --mount "type=bind,source=$RUNNER_TEMP/ort-results,target=/results" \
+            --mount "type=bind,source=$RUNNER_TEMP/ort-home,target=/home/ort" \
+            ghcr.io/oss-review-toolkit/ort:92.0.0@sha256:b756f9ae0b8d6b435012a1b7097d4e419d327029cd8daeb36c7f400af9b51d31 \
+            --warn evaluate -i /results/analyzer-result.json -o /results -f JSON \
+            --rules-file /project/.ort/evaluator.rules.kts
+          result=$?
+          set -e
+          python3 - <<'PY'
+          import json
+          import os
+          from pathlib import Path
+
+          results = Path(os.environ["RUNNER_TEMP"]) / "ort-results"
+          analysis = json.loads((results / "analyzer-result.json").read_text())
+          evaluation = results / "evaluation-result.json"
+          packages = analysis["analyzer"]["result"]["packages"]
+          with open(os.environ["GITHUB_STEP_SUMMARY"], "a") as summary:
+              summary.write(f"## ORT licence review\n\n{len(packages)} packages analysed.\n\n")
+              if evaluation.exists():
+                  violations = json.loads(evaluation.read_text())["evaluator"]["violations"]
+                  if violations:
+                      summary.write("| Package | Licence | Finding |\n| --- | --- | --- |\n")
+                      for violation in violations:
+                          package = violation["pkg"]
+                          licence = violation.get("license") or "Unknown"
+                          message = violation["message"]
+                          summary.write(f"| {package} | {licence} | {message} |\n")
+                  else:
+                      summary.write("All package licences matched the pilot allowlist.\n")
+              else:
+                  summary.write("ORT did not produce an evaluation result. Check the job log.\n")
+          PY
+          exit "$result"
+      - uses: actions/upload-artifact@v7.0.2
+        if: always()
+        with:
+          name: ort-licence-results
+          path: |
+            ${{ runner.temp }}/ort-results/*.json
+            ${{ runner.temp }}/ort-results/pr-number
+          if-no-files-found: warn
diff --git a/.ort/evaluator.rules.kts b/.ort/evaluator.rules.kts
new file mode 100644
index 0000000..0acc8f4
--- /dev/null
+++ b/.ort/evaluator.rules.kts
@@ -0,0 +1,48 @@
+val allowedLicences = setOf(
+    "MIT",
+    "Apache-2.0",
+    "0BSD",
+    "BSD-1-Clause",
+    "BSD-2-Clause",
+    "BSD-3-Clause",
+    "BSL-1.0",
+    "ISC",
+    "Zlib"
+).map { it.toSpdx() as SpdxSingleLicenseExpression }.toSet()
+
+fun PackageRule.LicenseRule.isOutsideAllowlist() = object : RuleMatcher {
+    override val description = "isOutsideAllowlist($license)"
+    override fun matches() = license !in allowedLicences
+}
+
+val licenceRules = ruleSet(ortResult, licenseInfoResolver, resolutionProvider) {
+    packageRule("UNAPPROVED_PACKAGE_LICENCE") {
+        require {
+            -isExcluded()
+        }
+
+        // ORT also visits the repository's project entries, which are not consumed packages.
+        if (pkg.metadata.id.type == "NuGet" && pkg.metadata.id.version.isNotEmpty()) {
+            if (pkg.metadata.declaredLicensesProcessed.spdxExpression == null) {
+                error(
+                    "No recognised licence was declared for ${pkg.metadata.id.toCoordinates()}.",
+                    "Review the package licence and record a justified curation before approving it."
+                )
+            }
+
+            licenseRule("UNAPPROVED_PACKAGE_LICENCE", LicenseView.CONCLUDED_OR_DECLARED_OR_DETECTED) {
+                require {
+                    -isExcluded()
+                    +isOutsideAllowlist()
+                }
+
+                error(
+                    "The licence $license for ${pkg.metadata.id.toCoordinates()} is outside the pilot allowlist.",
+                    "Review the licence before adding it to the allowlist or record a justified exception."
+                )
+            }
+        }
+    }
+}
+
+ruleViolations += licenceRules.violations