diff --git a/CHANGES.md b/CHANGES.md
index 6112810..257a43b 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -2,7 +2,8 @@
 
 ## 4.0.4 (unreleased)
 
-- nothing yet
+- Fix #47: Do not add packages with capital names uncommented at the bottom ignore list when checked out.
+  [petschki]
 
 ## 4.0.3 (2024-05-17)
 
diff --git a/src/mxdev/processing.py b/src/mxdev/processing.py
index 280e8b4..8200e46 100644
--- a/src/mxdev/processing.py
+++ b/src/mxdev/processing.py
@@ -223,7 +223,7 @@ def write_dev_overrides(
     fio.write("#" * 79 + "\n")
     fio.write("# mxdev constraint overrides\n")
     for pkg, line in overrides.items():
-        if pkg in package_keys:
+        if pkg.lower() in [k.lower() for k in package_keys]:
             fio.write(
                 f"# {line} IGNORE mxdev constraint override. Source override wins!\n"
             )