diff --git a/.gitignore b/.gitignore
index 1371200..38c5c3b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -83,3 +83,7 @@ project_index.json
 # Auto Claude generated files
 .security-key
 logs/security/
+
+# Source data files (large, one-time use)
+data/krs_pdfs/
+data/ceidg_json/