diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 63862c2..e674233 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -18,4 +18,5 @@
 - Keep descriptions concise but enough for someone to replicate
 - If your use case doesn't fit an existing category, suggest a new one in your PR
 - Duplicates are fine if the approach is meaningfully different
-- Don't use AI to come up with new use cases. Only suggest use cases you have actually tested and verified.
\ No newline at end of file
+- Don't use AI to come up with new use cases. Only suggest use cases you have actually tested and verified.
+- **No crypto-related use cases** — these will not be accepted.
\ No newline at end of file
diff --git a/README.md b/README.md
index d7feb54..2d01557 100644
--- a/README.md
+++ b/README.md
@@ -60,3 +60,5 @@ We welcome contributions! See [CONTRIBUTING.md](CONTRIBUTING.md) for guidelines.
 - Improve existing ones
 
 > Please only submit usecases you have already worked with and verified that works (at least for a day). We value real ideas that make our lives actually better, not worse!
+>
+> **Note:** We do not accept use cases related to crypto.