diff --git a/.github/workflows/third_party_notices.yml b/.github/workflows/third_party_notices.yml
new file mode 100644
index 0000000000..24f63715d7
--- /dev/null
+++ b/.github/workflows/third_party_notices.yml
@@ -0,0 +1,19 @@
+---
+# yamllint disable rule:line-length
+name: Check for updated Third Party Notices
+
+on:  # yamllint disable-line rule:truthy
+  pull_request:
+
+jobs:
+  third-party-notices:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5.1.0
+        with:
+          python-version: '3.12'
+      - name: Run the generator
+        run: |
+          python Support/Python/unitybuild/generate_notice.py
+          git diff --exit-code
diff --git a/Support/Python/unitybuild/generate_notice.py b/Support/Python/unitybuild/generate_notice.py
new file mode 100644
index 0000000000..28a5e19863
--- /dev/null
+++ b/Support/Python/unitybuild/generate_notice.py
@@ -0,0 +1,81 @@
+# Copyright 2020 The Tilt Brush Authors
+# Copyright 2024 The Open Brush Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import os
+import io
+import re
+import codecs
+
+
+class BuildFailed(Exception):
+    pass
+
+
+def create_notice_file(project_dir):
+    def iter_notice_files():
+        """Yields (library_name, notice_file_name) tuples."""
+        root = os.path.join(project_dir, "Assets/ThirdParty")
+        if not os.path.exists(root):
+            raise BuildFailed("Cannot generate NOTICE: missing %s" % root)
+        for r, _, fs in os.walk(root):
+            for f in fs:
+                if f.lower() in (
+                    "notice",
+                    "notice.txt",
+                    "notice.tiltbrush",
+                    "notice.md",
+                ):
+                    yield (os.path.basename(r), os.path.join(r, f))
+        root = os.path.join(project_dir, "Assets/ThirdParty/NuGet/Packages")
+        if not os.path.exists(root):
+            raise BuildFailed("Cannot generate NOTICE: missing %s" % root)
+        for r, _, fs in os.walk(root):
+            for f in fs:
+                if f.lower() in ("notice", "notice.md", "notice.txt"):
+                    m = re.match(r"\D+", os.path.basename(r))
+                    if m:
+                        name = m.group(0).rstrip(".")
+                        if name[-2:] == ".v" or name[-2:] == ".V":
+                            name = name[:-2]
+                        yield (name, os.path.join(r, f))
+
+    tmpf = io.StringIO()
+    tmpf.write(
+        """This file is automatically generated.
+This software makes use of third-party software with the following notices.
+"""
+    )
+    for library_name, notice_file in iter_notice_files():
+        tmpf.write("\n\n=== %s ===\n" % library_name)
+        with open(notice_file) as inf:
+            contents = inf.read()
+            if contents.startswith(str(codecs.BOM_UTF8)):
+                contents = contents[len(codecs.BOM_UTF8) :]
+        tmpf.write(contents)
+        tmpf.write("\n")
+
+    output_filename = os.path.join(
+        project_dir, "Support/ThirdParty/GeneratedThirdPartyNotices.txt"
+    )
+    with open(output_filename, "w") as outf:
+        outf.write(tmpf.getvalue())
+
+
+def main(project_dir):
+    create_notice_file(project_dir)
+
+
+if __name__ == "__main__":
+    create_notice_file(os.getcwd())