diff --git a/OPEN_SOURCE_CREDITS.md b/OPEN_SOURCE_CREDITS.md
new file mode 100644
index 00000000..be65eebc
--- /dev/null
+++ b/OPEN_SOURCE_CREDITS.md
@@ -0,0 +1,25 @@
+# Open Source Credits
+
+QuotaKit is built in part from [CodexBar](https://github.com/steipete/CodexBar) by Peter Steinberger, licensed under the MIT License.
+
+QuotaKit is maintained by Columbus Labs as a product fork. The QuotaKit product layer adds its own iCloud sync experience, iPhone companion app, quota alerts, cost dashboards, Home Screen and Lock Screen widgets, share cards, setup flow, release pipeline, bundle identifiers, StoreKit products, and support surface.
+
+## User-Facing Attribution
+
+Use this as baseline copy anywhere QuotaKit presents open-source credits in the app, website, App Store support materials, or release notes:
+
+> QuotaKit is built in part from CodexBar by Peter Steinberger, licensed under the MIT License. QuotaKit adds Columbus Labs’ iCloud sync, iPhone companion app, dashboards, alerts, widgets, share cards, setup flow, releases, and support.
+
+## Product Boundary
+
+QuotaKit should stay transparent about its upstream roots while making a clear distinction between the open-source-derived foundation and the Columbus Labs product work layered on top.
+
+Reasonable paid features include QuotaKit-specific product value such as iPhone companion features, richer dashboards, widgets, alerts, share/export tools, advanced provider views, cloud/sync polish, support, and other convenience features developed for QuotaKit.
+
+Avoid presenting upstream CodexBar work as solely Columbus Labs work. Also avoid moving unchanged upstream functionality behind a paywall in a way that makes QuotaKit feel like a near-clone with attribution hidden.
+
+## License Notes
+
+The MIT license notice and Peter Steinberger copyright notice must remain included with substantial portions of the software. The root `LICENSE` file preserves that notice.
+
+This document is not legal advice. It is a product and attribution guideline for keeping QuotaKit’s open-source relationship clear and respectful.
diff --git a/README.md b/README.md
index 21fc0f4d..e54cd52d 100644
--- a/README.md
+++ b/README.md
@@ -76,6 +76,8 @@ Columbus Labs maintains QuotaKit as a product fork with its own releases, setup
 
 The Git history intentionally preserves upstream commits and contributors. That is why GitHub may show thousands of historical commits and many contributors even though Columbus Labs owns the QuotaKit product boundary.
 
+See [OPEN_SOURCE_CREDITS.md](OPEN_SOURCE_CREDITS.md) for recommended user-facing attribution copy and QuotaKit's product-boundary guidance.
+
 ## License
 
 MIT. See [LICENSE](LICENSE).